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Susitna-Watana Hydroelectric Project Document
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2012 upper Susitna River fish distribution and habitat study : habitat report
SuWa 189
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2012 Environmental Studies
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Susitna-Watana Hydroelectric Project document number 189
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[Anchorage, Alaska : Alaska Energy Authority, 2013]
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February 2013
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Susitna-Watana Hydroelectric Project
(FERC No. 14241)
2012 Upper Susitna River Fish Distribution
and Habitat Study
Habitat Report
Prepared for
Alaska Energy Authority
Prepared by
HDR Alaska, Inc
2525 C Street
Suite 305
Anchorage, AK 99503
February 2013
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page i February 2013
TABLE OF CONTENTS
Summary ...................................................................................................................................... vii
1. Introduction ..............................................................................................................................1
2. Fish Passage Barriers Assessment ..........................................................................................1
2.1. Study Objectives ........................................................................................................2
2.2. Study Area .................................................................................................................2
2.3. Methods .....................................................................................................................2
2.4. Quality Control ..........................................................................................................4
2.5. Deviations from Study Plan ......................................................................................4
2.6. Results .......................................................................................................................4
2.7. Discussion and Conclusion .......................................................................................6
3. Aquatic Habitat Mapping Study ............................................................................................7
3.1. Study Objectives ........................................................................................................7
3.2. Study Area .................................................................................................................7
3.3. Methods .....................................................................................................................7
3.3.1. Aquatic Habitat Characterization and Mapping ......................................... 7
3.3.2. Data Analysis ............................................................................................ 11
3.3.3. Data Review and Quality Control ............................................................. 11
3.4. Deviations from Study Plan ....................................................................................12
3.4.1. Video-Based Deviations ........................................................................... 12
3.4.2. Ground-Based Deviations ......................................................................... 12
3.5. Results .....................................................................................................................13
3.5.1. Aerial Habitat Mapping ............................................................................ 13
3.5.2. Ground-Based Habitat Mapping ............................................................... 14
3.6. Discussion and Conclusion .....................................................................................21
3.6.1. Aerial Habitat Mapping ............................................................................ 21
3.6.2. Ground-Based Habitat Mapping ............................................................... 22
4. References ...............................................................................................................................23
5. Tables ......................................................................................................................................25
6. Figures .....................................................................................................................................91
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page ii February 2013
LIST OF TABLES
Table 1. Fish passage barrier descriptions. The Barrier ID reflects the Susitna historic river
mile where the tributary enters the river and the letters denote multiple barriers within
the same tributary. ................................................................................................................. 25
Table 2. Susitna River Mainstem and Mesohabitat Type Descriptions1 ...................................... 28
Table 3. Substrate Classification ................................................................................................... 30
Table 4. Riparian Vegetation Classification ................................................................................. 31
Table 5. Stream Cover Types ........................................................................................................ 31
Table 6. Jay Creek Reach 1 – Mainstem Summary Statistics (Mapped Habitat Units) ............... 32
Table 7. Jay Creek Reach 1 – Mainstem Riparian Vegetation ..................................................... 33
Table 8. Jay Creek Reach 1 - Mainstem Substrate ....................................................................... 33
Table 9. Jay Creek Reach 1 – Side Channel Summary Statistics (Mapped Habitat Units) .......... 34
Table 10. Jay Creek Reach 1 – Side Channel Riparian Vegetation .............................................. 35
Table 11. Jay Creek Reach 1 – Side Channel Substrate ............................................................... 36
Table 12. Jay Creek - Reach 2 - Mainstem Summary Statistics (Mapped Habitat Units) ............ 37
Table 13. Jay Creek Reach 2 - Mainstem Riparian Vegetation .................................................... 38
Table 14. Jay Creek Reach 2 – Mainstem Substrate ..................................................................... 38
Table 15. Jay Creek Reach 6 – Mainstem Summary Statistics (Mapped Habitat Units) ............. 39
Table 16. Jay Creek Reach 6 – Mainstem Riparian Vegetation ................................................... 40
Table 17. Jay Creek Reach 6 – Mainstem Substrate ..................................................................... 40
Table 18. Jay Creek Reach 6 - Side Channel Summary Statistics (Mapped Habitat Units) ......... 41
Table 19. Jay Creek Reach 6 – Side Channel Riparian Vegetation .............................................. 42
Table 20. Jay Creek Reach 6 – Side Channel Substrate ............................................................... 42
Table 21. Kosina Creek Reach 1 – Mainstem Summary Statistics (Mapped Habitat Units) ....... 43
Table 22. Kosina Reach 1 – Mainstem Riparian Vegetation ........................................................ 44
Table 23. Kosina Reach 1– Mainstem Substrate .......................................................................... 44
Table 24. Kosina Creek Reach 1 – Side Channel Summary Statistics (Mapped Habitat Units) .. 45
Table 25. Kosina Reach 1 – Side Channel Riparian Vegetation .................................................. 46
Table 26. Kosina Creek Reach 1 – Side Channel Substrate ......................................................... 46
Table 27. Kosina Creek Reach 2 – Mainstem Summary Statistics (Mapped Habitat Units) ....... 47
Table 28. Kosina Creek Reach 2 – Mainstem Riparian Vegetation ............................................. 48
Table 29. Kosina Creek Reach 2 – Mainstem Substrate ............................................................... 48
Table 30. Kosina Reach 2 – Side Channel Summary Statistics (Mapped Habitat Units) ............ 49
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page iii February 2013
Table 31. Kosina Reach 2 – Side Channel Riparian Vegetation .................................................. 50
Table 32. Kosina Reach 2 – Side Channel Substrate .................................................................... 50
Table 33. Kosina Creek Reach 3 – Mainstem Summary Statistics (Mapped Habitat Units) ....... 51
Table 34. Kosina Creek Reach 3 – Mainstem Riparian Vegetation ............................................. 52
Table 35. Kosina Creek Reach 3 – Mainstem Substrate ............................................................... 52
Table 36. Kosina Creek Reach 3 – Side Channel Summary Statistics (Mapped Habitat Units) .. 53
Table 37. Kosina Creek Reach 3 – Side Channel Riparian Vegetation ........................................ 54
Table 38. Kosina Reach 3 – Side Channel Substrate .................................................................... 54
Table 39. Kosina Creek Reach 4 – Mainstem Summary Statistics (Mapped Habitat Units) ....... 55
Table 40. Kosina Creek Reach 4 – Mainstem Riparian Vegetation ............................................. 56
Table 41. Kosina Creek Reach 4 – Mainstem Substrate ............................................................... 56
Table 42. Kosina Reach 4 – Side Channel Summary Statistics (Mapped Habitat Units) ............ 57
Table 43. Kosina Creek Reach 4 – Side Channel Riparian Vegetation ........................................ 58
Table 44. Kosina Creek Reach 4 – Side Channel Substrate ......................................................... 58
Table 45. Kosina Creek Reach 5 – Mainstem Summary Statistics (Mapped Habitat Units) ....... 59
Table 46. Kosina Creek Reach 5 – Mainstem Riparian Vegetation ............................................. 60
Table 47. Kosina Creek Reach 5 – Mainstem Substrate ............................................................... 60
Table 48. Kosina Creek Reach 5 – Side Channel Summary Statistics (Mapped Habitat Units) .. 61
Table 49. Kosina Creek Reach 5 – Side Channel Riparian Vegetation ........................................ 62
Table 50. Kosina Creek Reach 5 – Side Channel Substrate ......................................................... 62
Table 51. Kosina Creek Reach 6 – Mainstem Summary Statistics (Mapped Habitat Units) ....... 63
Table 52. Kosina Creek Reach 6 – Mainstem Riparian Vegetation ............................................. 64
Table 53. Kosina Creek Reach 6 – Mainstem Substrate ............................................................... 64
Table 54. Kosina Creek Reach 7 – Mainstem Summary Statistics (Mapped Habitat Units) ....... 65
Table 55. Kosina Creek Reach 7 – Mainstem Riparian Vegetation ............................................. 66
Table 56. Kosina Creek Reach 7 – Mainstem Substrate ............................................................... 66
Table 57. Kosina Reach 7 – Side Channel Summary Statistics (Mapped Habitat Units) ............ 67
Table 58. Kosina Reach 7 – Side Channel Riparian Vegetation .................................................. 68
Table 59. Kosina Reach 7 – Side Channel Substrate .................................................................... 68
Table 60. Kosina Creek Reach 8 – Mainstem Summary Statistics (Mapped Habitat Units) ....... 69
Table 61. Kosina Creek Reach 8 – Mainstem Riparian Vegetation ............................................. 70
Table 62. Kosina Creek Reach 8 – Mainstem Substrate ............................................................... 70
Table 63. Kosina Creek Reach 8 – Side Channel Summary Statistics (Mapped Habitat Units) .. 71
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page iv February 2013
Table 64. Kosina Creek Reach 8 – Side Channel Riparian Vegetation ........................................ 72
Table 65. Kosina Creek Reach 8 – Side Channel Substrate ......................................................... 72
Table 66. Watana Creek Reach 1 – Mainstem Summary Statistics (Mapped Habitat Units) ...... 73
Table 67. Watana Creek Reach 1 – Mainstem Riparian Vegetation ............................................ 74
Table 68. Watana Creek Reach 1 – Mainstem Substrate .............................................................. 74
Table 69. Watana Creek Reach 3 – Mainstem Summary Statistics (Mapped Habitat Units) ...... 75
Table 70. Watana Creek Reach 3 – Mainstem Riparian Vegetation ............................................ 76
Table 71. Watana Creek Reach 3 – Mainstem Substrate .............................................................. 76
Table 72. Watana Creek Reach 3 – Side Channel Summary Statistics (Mapped Habitat Units) . 77
Table 73. Watana Creek Reach 3 – Side Channel Riparian Vegetation ....................................... 78
Table 74. Watana Creek Reach 3 – Side Channel Substrate ........................................................ 78
Table 75. Watana Creek Reach 4- Mainstem Summary Statistics (Mapped Habitat Units) ........ 79
Table 76. Watana Creek Reach 4 – Mainstem Riparian Vegetation ............................................ 80
Table 77. Watana Creek Reach 4 – Mainstem Substrate .............................................................. 80
Table 78. Watana Creek Reach 4 – Side Channel Summary Statistics (Mapped Habitat Units) . 81
Table 79. Watana Creek Reach 4 – Side Channel Riparian Vegetation ....................................... 82
Table 80. Watana Creek Reach 4 – Side Channel Substrate ........................................................ 82
Table 81. Watana Creek Reach 6 – Mainstem Summary Statistics (Mapped Habitat Units) ...... 83
Table 82. Watana Creek Reach 6 – Mainstem Riparian Vegetation ............................................ 84
Table 83. Watana Creek Reach 6 – Mainstem Substrate .............................................................. 84
Table 84. Watana Creek Reach 6 – Side Channel Summary Statistics (Mapped Habitat Units) . 85
Table 85. Watana Creek Reach 6 – Side Channel Riparian Vegetation ....................................... 86
Table 86. Watana Creek Reach 6 – Side Channel Substrate ........................................................ 86
Table 87. Mesohabitat Unit Descriptions for 2013 ...................................................................... 87
Table 88. Upper River tributaries and mainstem Susitna River sections aerial videotaped in
2012 ....................................................................................................................................... 89
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page v February 2013
LIST OF FIGURES
Figure 1 – Fish passage barriers survey extent and locations within the eastern half of the
study area. ............................................................................................................................. 93
Figure 2 – Fish passage barriers survey extent and locations within the western half of the
study area. ............................................................................................................................. 95
Figure 3 – Study Area map with streams where data were collectered highlighted. .................... 97
Figure 4 – Jay Creek reach Map. .................................................................................................. 99
Figure 5 – Jay Creek Reach 1 Mesohabitat Survey. ................................................................... 101
Figure 6 – Jay Creek Reach 2 Mesohabitat Survey. ................................................................... 103
Figure 7 – Jay Creek Reach 6 Mesohabitat Survey. ................................................................... 105
Figure 8 – Kosina Creek Reach Map. ......................................................................................... 107
Figure 9 – Kosina Creek Reach 1 Mesohabitat Survey. ............................................................. 109
Figure 10 – Kosina Creek Reaches 2 and 3 Mesohabitat Surveys. ............................................ 111
Figure 11 – Kosina Creek Reach 4 Mesohabitat Units Surveyed. .............................................. 113
Figure 12 – Kosina Creek Reaches 5, 6, and 7 Mesohabitat Units Surveyed. ............................ 115
Figure 13 – Kosina Creek Reach 8 Mesohabitat Units Surveyed. .............................................. 117
Figure 14 – Watana Creek Reaches ............................................................................................ 119
Figure 15 – Watana Creek Reach 1 Mesohabitat Units Surveyed. ............................................. 121
Figure 16 – Watana Creek Reaches 3 and 4 Mesohabitat Units Surveyed. ................................ 123
Figure 17 – Watana Creek Reach 4 Mesohabitat Units Surveyed. ............................................. 125
Figure 18 – Watana Creek Reach 6 Mesohabitat Units Surveyed. ............................................. 127
Figure 19 – Example video capture of a tributary mid-channel scour pool in a confined
channel with boulder and cobble substrate and no stream wood visible. ........................... 129
Figure 20 – Example video capture of the Middle River in the vicinity of RM 100.5. .............. 129
Figure 21 – Example video capture of the Lower River in the vicinity of RM 65. .................... 130
APPENDICES
Appendix A. Streams surveyed for fish passage barriers
Appendix B. Fish Passage Barriers – Photos
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page vi February 2013
LIST OF ACRONYMS AND SCIENTIFIC LABELS
Abbreviation Definition
AEA Alaska Energy Authority
ADF&G Alaska Department of Fish and Game
ADNR Alaska Department of Natural Resources
AG above ground
ATWG Aquatic Technical Workgroup
cfs cubic feet per second
FERC Federal Energy Regulatory Commission
GIS Geographic Information System
GPS global positioning system
HD high definition
ILP Integrated Licensing Process
km kilometer
LWD large woody debris
m meter
mph miles per hour
NEPA National Environmental Policy Act
Project Susitna-Watana Hydroelectric Project
QC quality control
RM Susitna River historic river mile
RSP Revised Study Plan
TWG Technical Workgroup
UCB undercut bank
USFS U.S. Department of Agriculture, Forest Service
USGS U.S. Geological Survey
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page vii February 2013
SUMMARY
The 2012 Upper River Habitat study has two major components: a fish barrier assessment and
habitat mapping study. The Fish Passage Barriers Assessment identified the locations of
potential fish passage barriers in tributary streams upstream of Devils Canyon. Information
regarding fish passage barriers, and specifically barriers to adult salmon migration, is important
to define the extent of potential Project effects to fish and aquatic habitat. These data will also
inform the planning and design of other Upper Susitna River studies related to fish distribution,
particularly juvenile and adult salmon surveys. The study area included all tributary streams
beginning at river mile (RM) 150 upstream to and including the Oshetna River at RM 233.5.
Named tributaries in the study area include Cheechako Creek, Chinook Creek, Devil Creek, Fog
Creek, Tsusena Creek, Deadman Creek, Watana Creek, Kosina Creek, Goose Creek and the
Oshetna River.
Aerial surveys were completed in the Upper Susitna River basin from June 18 through June 22,
2012. The typical flight path started at the tributary confluence with the mainstem Susitna River
and proceeded upstream to the 3,000-ft elevation contour, the highest elevation at which salmon
have been observed in prior investigations. The survey was terminated at the first determined
barrier or when the 3,000-ft elevation contour was reached. Physical features were defined as
barriers to adult Chinook salmon passage if the vertical height was greater than 10 ft.
Surveys were flown on a total of 79 tributary drainages to the Upper Susitna River, with 41
drainages above and 38 drainages below the proposed dam site (RM 184). Approximately 815
tributary stream miles were evaluated. A total of 43 potential fish passage barriers were
identified within 29 of the 79 drainages surveyed. Of these 43 barriers, 35 definitive fish passage
barriers were identified within 24 tributaries.
The mainstem Susitna River between RM 150 and RM 227 is moderately confined, lying within
an incised valley or canyon for most of its length. Where a limited floodplain exists, smaller
tributaries generally have a short reach of relatively low-gradient streambed. This abruptly
changes to a steep gradient when the tributary stream reaches the valley or canyon walls. All
barriers were located in these high-gradient sections. Some streams had multiple barriers, but the
first barrier was usually within 0.5 mile of the Susitna River confluence. In general, results
indicated that the larger the tributary, the further upstream the first barrier was located. Above
the proposed dam site, three tributaries contained definitive fish passage barriers within the
inundation zone (i.e., below an elevation of 2,050 ft) of the proposed Project. Barriers on two of
these tributaries (RM 194.9 Creek and RM 200.7 Creek) were located slightly below the
maximum elevation of the inundation zone. Therefore, under certain Project conditions, access to
previously inaccessible aquatic habitat would be available. The barrier on Deadman Creek is
within the inundation zone but below the operational zone of the proposed Project and therefore,
would be inundated permanently; providing year round access to approximately 44 miles of
previously inaccessible aquatic habitat.
The Habitat Mapping Study was initiated in 2012 to contribute to existing aquatic meso-habitat
information within the mainstem Susitna River and selected tributaries in the Upper Susitna
River watershed above Devils Canyon (approximately RM 150-152) upstream to and including
the Oshetna River (RM 233.5). Information regarding aquatic habitat, and specifically, habitat
within the inundation zone, will provide data relevant to establishing an environmental baseline
to evaluate potential Project-related effects to fish and fish habitat.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page viii February 2013
In order to characterize aquatic habitat at an informative level of resolution and over a broad
geographic area, a multi-faceted mapping approach was developed that included a combination
of aerial and ground-based aquatic mesohabitat mapping methodologies. Aerial habitat mapping
was meant to complement ground-based meso-habitat surveys. However, challenges with
accessing high gradient streams by foot resulted in aerial mapping being the primary method
used in 2012. Excellent conditions (i.e. weather, low flow levels, clear water, and open canopy of
stream corridors) resulted in quality aerial video footage of all primary tributaries in the Upper
Susitna River, the Upper Susitna River mainstem, and the Middle Susitna River mainstem (RM
98.0-184) between September 7 and September 12. Ground-based habitat characterization
occurred on three tributaries (Jay Creek, Watana Creek, and Kosina Creek) and was employed to
verify the aerial videography methods and to further characterize potential anadromous salmon
and resident fish habitat. The primary data collected was meso-habitat type and length. In
addition and where feasible, stream gradient, channel type, substrate, large woody debris,
riparian vegetation and presence of undercut banks were also recorded during ground-based
surveys.
Jay Creek, Kosina Creek, and Watana Creek were partitioned into seven, eight, and eight
geomorphic reaches, respectively, to facilitate study objectives. Based on GIS analysis, stream
lengths below 3,000 ft elevation (i.e., the highest elevation at which salmon have been observed)
are 21.7 km for Jay Creek, 29.3 km for Kosina Creek, and 33.9 km for Watana Creek.
Approximately 2.05 km (9.4%) of Jay Creek, 6.4 km (21.8%) of Kosina Creek, and 2.3 km
(6.8%) of Watana Creek were ground surveyed. Post-field collection review of the video footage
determined that imagery collected via this methodology can be reliably used for characterizing
meso-habitat frequency and distribution in the Upper and Middle Susitna River mainstem and its
tributaries in combination with foot surveys for ground truthing.
Differences in meso-habitat type composition between main channel and side channels in all
three creeks surveyed appeared to be driven by the different hydrologic regimes that would be
expected. Riffle and run were the dominant meso-habitat types in main channels. Habitat
characteristics in mainstem channel meso-habitats generally included greater bankfull and wetted
widths, greater average maximum depths, larger substrates, and less large woody debris (LWD)
than side channels. Although main channel riffle and run meso-habitat types appeared to
compose most of the total length of stream reaches surveyed, side channels, when present,
appeared to have a greater diversity of meso-habitat types. Side channels generally included
more LWD, cover, and overhanging vegetation, and a greater range of substrate, including
smaller materials, than main channels. Non-forest shrub alder and willow were the dominant
riparian vegetation types in most main channel habitats.
In evaluating the study results as it relates to fisheries resources, information suggests that main
channel and side channel habitats in the surveyed tributaries function to support different life
history stages of fish species present within the Susitna River Basin. Main channel habitats,
which are primarily composed of riffle and run meso-habitat types are better suited to support
sub-adult and adult fish. The presence of higher velocities in this channel type may create less
suitable conditions for smaller fish, particularly at high flows. Higher overall complexity within
side channel habitats, as observed in this study, likely supports a greater variety of life history
stages for fish species including juvenile fish. The greater availability of LWD and cover
increases productivity and the available food base and creates refugia that may reduce
bioenergetic expenditure (due to lower velocities) and reduce predation of juvenile fish.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page ix February 2013
Although main channel and side channel habitats may tend to support specific life history stages,
the availability of both habitats in tributary systems is critical to supporting the overall health of
fishery resources in the Susitna River Basin.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 1 February 2013
1. INTRODUCTION
The Alaska Energy Authority (AEA) is preparing a License Application that will be submitted to
the Federal Energy Regulatory Commission (FERC) for the proposed Susitna-Watana
Hydroelectric Project, FERC No. 14241 (Project) using the Integrated Licensing Process (ILP).
The Project would be located on the Susitna River, an approximately 300-mile-long river in
Southcentral Alaska. The Project’s dam site would be located at historic river mile1 (RM) 184.
The 2012 Upper Susitna River Fish Distribution and Habitat Study was implemented to collect
information on fish distribution and abundance and to characterize aquatic habitat in the Upper
Susitna River watershed. The Upper Susitna River is defined as the river reach above the
proposed dam site (RM 184).
The 2012 Upper Susitna River Fish Distribution and Habitat Study Plan (AEA 2012) identified
three goals:
1) Characterize aquatic habitat in the Susitna River and its tributaries/lakes above Devils
Canyon upstream to and including the Oshetna River.
2) Determine the distribution and relative abundance of adult Chinook salmon in the Susitna
River and its tributaries above Devils Canyon upstream to and including the Oshetna River.
3) Determine the distribution and relative abundance of juvenile Chinook salmon and other
fish species present in the Susitna River and its tributaries and lakes above Devils Canyon
upstream to and including the Oshetna River up to 3,000-foot elevation.
To address the objectives of the study, AEA initiated four component studies in 2012 including
the Fish Passage Barriers Assessment, the Aquatic Habitat Mapping Study, the Adult Salmon
Spawning Ground Surveys, and the Distribution of Juvenile Chinook and Other Species in the
Upper Sustina River Study (Fish Distribution Study). This report includes the result of the Fish
Passage Barriers Assessment and the Aquatic Habitat Mapping Study.
This information will inform the 2013–2014 licensing study program, Exhibit E of the License
Application, and FERC’s National Environmental Policy Act (NEPA) analysis for the Project
license.
2. FISH PASSAGE BARRIERS ASSESSMENT
The Fish Passage Barriers Assessment (Barriers Assessment) was initiated in 2012 to contribute
to the description of existing fish habitat within the Susitna River by identifying the locations of
potential fish passage barriers in tributaries upstream of Devils Canyon. Information regarding
fish passage barriers, and specifically barriers to adult salmon migration, is important to define
the extent of potential Project effects to fish and aquatic habitat and will inform the planning and
1 River mile (RM) designations used in this document pertaining to the main Susitna River are based on the historic river mile
system established in the 1980s. A new, Project river mile system based on modern channel mapping will be adopted in future
reporting. River miles were interpolated to the nearest tenth to facilitate spatial referencing of tributary confluences with the
Susitna River and other features.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 2 February 2013
design of other Upper Susitna River studies related to fish distribution, particularly juvenile and
adult salmon surveys.
2.1. Study Objectives
The primary objective of the Barriers Assessment was to identify the locations of potential
barriers to upstream fish migrations, specifically Chinook salmon, given that a barrier to this
species would also present a barrier to all other species present in Susitna River tributaries above
Devils Canyon. Information collected from the Barriers Assessment will contribute to Goal 1 and
is identified in the 2012 Upper Susitna River Fish Distribution and Habitat Study Plan (AEA
2012) as Objective 1.4.
2.2. Study Area
The study area for the Barriers Assessment included all tributary streams beginning at RM 150
(just downstream of Devils Canyon) upstream to and including the Oshetna River at RM 233.5
(Figures 1 and 2). Named tributaries in the study area include Cheechako Creek, Chinook Creek,
Devil Creek, Fog Creek, Tsusena Creek, Deadman Creek, Watana creek, Kosina Creek, Goose
Creek and the Oshetna River. The upper extent of tributaries in the study area was the 3,000-ft
elevation contour.
2.3. Methods
Prior to conducting field surveys, a literature review of available information related to stream
channel geomorphology in the Upper Susitna River was completed. The information consisted of
data collected during the 1980s (ADF&G 1981a) and recent fish distribution studies completed
by the Alaska Department of Fish and Game (ADF&G) (Buckwalter 2011a). The literature
review identified the locations of large waterfalls on Devil Creek, Deadman Creek, and Tsusena
Creek. In addition, a desktop analysis was conducted using U.S. Geological Survey (USGS) 100-
foot contour topographic data and mapped streams to identify the initial pool of tributary streams
greater than 1 mile in length for assessment by aerial survey.
Aerial surveys of all tributaries identified from the literature review and desktop analysis were
conducted by helicopter. The typical flight path started at the tributary confluence with the
mainstem Susitna River and proceeded upstream to the 3,000-foot elevation contour2, the highest
elevation at which salmon have been observed in prior investigations (Buckwalter 2011b). The
survey was terminated at the first determined barrier or when the 3,000-foot elevation contour
was reached. Occasionally surveys were terminated below the 3,000-foot elevation if observers,
using best professional judgment, determined that the habitat appeared unsuitable to support
Chinook salmon spawning. Factors used for this determination included low stream flow that
lacked sufficient water depth for adult salmon or steep and sustained gradients (greater than 20
percent). If a barrier was observed within the proposed reservoir inundation zone, the survey was
continued upstream to the 3,000-foot elevation contour. During field surveys, physical features
of potential fish passage barriers were evaluated based on the Alaska Forest Resources and
Practices Regulations (ADNR 2007) and the methods outlined by Powers and Orsborn (1985),
2 Buckwalter (2011b) captured juvenile Chinook salmon in a tributary of Fog Creek at an elevation slightly below 3,000 feet.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 3 February 2013
and were considered a definitive barrier to adult Chinook salmon passage if a feature’s vertical
height was greater than 10 feet. Global positioning system (GPS) coordinates and photographs of
all potential barriers were obtained and physical features were described.
Observers used the vertical height of adjacent spruce trees or other forest vegetation to provide a
relative scale for water fall heights when making visual estimations from the helicopter. Water
falls were termed “potential fish passage barriers” if helicopter observations could not
unequivocally determine a vertical height greater than 10 feet. Ground surveys were conducted
to measure physical features of potential barriers. These were performed at the time of the
surveys when the estimated falls height was close to 10 feet and a helicopter landing zone was
available within a reasonable approach distance. A Laser Tech Tru Pulse 200 laser rangefinder
was used to calculate the height (vertical distance from the falls crest to the plunge pool standing
wave), the horizontal distance (falls crest to plunge pool standing wave), and slope of these
barriers. From a fixed position, sightings were made at two positions on the falls: one at the crest
of the falls and the second at the plunge pool at the base of the falls. From these sightings the
vertical and horizontal distances were calculated. Because moving water does not provide a
good reflective surface for the laser, sightings were made on adjacent hard features, such as
boulders or cliff faces.
During the surveys, potential fish passage barriers were classified based on physical
characteristics described by Powers and Orsborn (1985) and Buckwalter et al. (2010), explained
below.
The following three physical categories were used to describe the overall permanence of the
barrier.
1) Fixed Permanent – feature is permanent (e.g., waterfall) and passage does not vary
seasonally; therefore, it is not dependent on natural variations in flow.
2) Fixed Seasonal – feature is permanent (e.g., waterfall), but passage for species may vary
seasonally, depending on flow conditions.
3) Temporary – feature is not permanent (e.g., beaver dam), but passage varies depending
primarily on flow conditions.
The following nine classes were used to identify the specific type of barrier.
1) Single Falls – stream flows through a single falls, offering only one path for fish passage.
2) Multiple Falls – stream divides through two or more channels, creating multiple falls in
parallel and offering the fish several passage routes of varying difficulty.
3) Simple Chute – stream flows through a chute of unvarying cross-section and constant
slope steepness with supercritical flow at all stages.
4) Complex Chute – stream flows through chutes of varying cross-sections with several
changes in bed slope with whitewater at all stages.
5) Boulder Cascades – stream flows through boulders that constrict flow, creating large
head losses from upstream to downstream with intermediate resting areas in very
turbulent pools.
6) Turbulent Cascades – stream flows through turbulent cascades where large instream
roughness elements or jutting rocks churn flow into surges, boils, eddies, and vortices
offering fish no resting areas.
7) Compound – stream flows through compound combinations of single falls and/or chutes.
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8) Beaver Dam – passage of some fish species may be hindered or blocked by the presence
of beaver dams or lodges.
9) Debris Jam –passage of some fish species may be hindered or blocked by the presence of
debris jams.
2.4. Quality Control
Quality control (QC) measures during survey events included employing two experienced
observers on each survey. Level 1 QC was performed on the field data forms at the end of each
day. Level 2 QC consisted on a line-by-line verification of electronic data with data on field
forms. In the Anchorage office, a QC III review was performed on the Geographic Information
System (GIS) database by a senior professional before submitting the database to AEA. QC IV
(database verification) and V (database verification by senior-level professionals) is ongoing.
2.5. Deviations from Study Plan
Changes to field methods from the 2012 Upper Susitna River Fish Distribution and Habitat
Study Plan (AEA 2012) included the following:
The study plan stated that observers would use an 11-foot vertical height as a
conservative height for constituting a passage barrier to Chinook salmon. In practice, 10
feet was a more familiar height for observers to visually estimate from the helicopter and
was adopted in the field. This is still considered a conservative figure given the
migratory distance from tidewater a salmon would have traveled prior to reaching any of
the barriers assessed within the study area.
The study plan stated that GPS locations, photos, drawings, and dimensions would be
recorded for all potential barriers that could not unequivocally be identified as a barrier.
Three potential barriers could not unequivocally be determined to have a height greater
than 10 feet from the helicopter and were measured from the ground. Additional
potential barriers were identified as having vertical heights less than 10 feet, but have
other features such as multiple chutes or cascades that in aggregate could constitute a
passage barrier. These features were not surveyed from the ground due to the lack of
suitable helicopter landing zones or inaccessibility of the terrain in which they were
located.
2.6. Results
Fish passage barrier surveys were completed in the Upper Susitna River basin from June 18
through June 22, 2012. Low-level aerial surveys were flown on a total of 79 tributary drainages
to the Upper Susitna River between RM 150.1 and 233.5 (Appendix A). Within the study area,
41 and 38 tributary drainages were surveyed above and below the proposed dam site (RM 184),
respectively. Approximately 815 tributary stream miles were evaluated (Figures 1 and 2).
Because the majority of tributaries surveyed do not have names, a naming convention was
adopted using the Susitna River RM to the nearest one-tenth mile at the point that the tributary
enters the Susitna River. For example, Devil Creek is designated “RM 161.5” because its
confluence with the Susitna River is at RM 161.5. Where second-order tributaries were surveyed,
they were designated as “L” for river left or “R” for river right (downstream view) and numbered
sequentially from downstream to upstream.
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A total of 43 potential fish passage barriers were identified from the helicopter within 29 of the
79 drainages surveyed (more than one barrier was identified on some tributaries) (Table 1). Of
these 43 barriers, a total of 35 definitive fish passage barriers were identified within 24
tributaries, the majority of which have falls with a vertical height greater than 10 feet and that
could be visually estimated from the helicopter. Three falls could not unequivocally be
determined to have vertical distances greater than 10 feet from the helicopter. These were
surveyed from the ground with a rangefinder to determine vertical and horizontal distances from
the falls crest to the plunge pool. All three were confirmed as barriers to fish passage (PB170.0-
B, PB179.1-A, and PB194.9-A) with measured distances of 15 feet, 15.7 feet, and 12.5 feet,
respectively. PB170.0-B is a multiple falls with the lower fall height of 10.8 feet and an upper
fall height of 4.2 feet. The plunge pool at the base of the lower falls is sloping and lacks
sufficient depth for a launch zone, leading observers to conclude that the lower falls alone
constitute the barrier. An additional eight features, within seven tributaries, were identified as
potential fish passage barriers having falls heights visually estimated to be less than 10 feet but
with other apparent elements of passage barriers such as multiple chutes and/or cascades that
warrant further investigation; however, their locations in canyons precluded landing the
helicopter for ground surveys. Appendix A summarizes the attributes of the 43 barriers and
Appendix B contains photographs and detailed descriptions of each barrier.
A majority (31 of 43, or 72 percent) of the fish passage barriers are located in tributaries
upstream of Devils Canyon to the proposed dam site (RM 184.0). As expected, barriers are more
common in the vicinity of Devils Canyon due to its steep walls. All of the 11 tributaries surveyed
in Devils Canyon have adult salmon passage barriers. Chinook Creek (RM 157.0) is the only
tributary lacking a barrier along its mainstem course, but does contain a barrier on a second order
tributary.
Above the proposed dam site, 4 of the 41 tributary streams surveyed were found to have
definitive barriers to the passage of adult salmon (Appendix A): Deadman Creek, RM 194.9
Creek, RM 200.7 Creek, and RM 226.8 Creek.
The falls crest of barrier PB186.6-A on Deadman Creek lies below the likely operational range
of the proposed reservoir, potentially resulting in fish passage between the reservoir and
Deadman Creek throughout the year. Deadman Creek has approximately 44 miles of mainstem
habitat between the existing fish passage barrier and the headwater lakes that would become
accessible to migratory fish. This upper reach was surveyed as well as the secondary tributary
draining the lakes near Tsusena Butte. No additional barriers were observed.
Barrier PB194.9-A on an unnamed stream (RM 194.9 Creek) is located slightly below the
proposed maximum pool elevation of 2,050 feet, based on the mapped location of the barrier
waypoint. Because the barrier is located close to the proposed maximum pool elevation, it would
likely be exposed during seasonal drawdowns of the reservoir. When the reservoir was at
maximum pool, fish would be able to pass over the barrier and access approximately 4 miles of
stream habitat and several small lakes close to the Fog Lakes system.
The unnamed tributary at RM 200.7 (RM 200.7 Creek) has a series of five falls, each of which is
a passage barrier to adult salmon. The uppermost barrier (PB 200.7 E) lies slightly below the
maximum pool elevation based on the location of the barrier waypoint. When the proposed
reservoir was at a maximum pool elevation of 2,050 feet, fish would be able to pass over the
barrier to access approximately 8 miles of habitat upstream. At the time of the survey, the
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proposed maximum pool elevation was 2,000 feet and PB200.7E was believed to be above the
maximum pool. Nonetheless, approximately 4 miles of the reach above PB200.7E was surveyed
and no additional barriers were identified.
The passage barrier on the unnamed creek at RM 226.8 (PB226.8A) was determined to be above
the proposed maximum pool elevation.
Three potential barriers were identified above the proposed dam site in the inundation zone on
unnamed creeks located at RM 186.9, RM 201.8, and RM 213.0. One potential barrier is on
RM186.9 Creek, a relatively small tributary (approximately 2 miles in length) that offers very
limited, if any, habitat for adult salmon spawning. Two potential barriers were identified on RM
201.8 Creek, both lying below the proposed maximum pool elevation. This tributary was
surveyed to above the 3,000-foot elevation contour and no additional barriers were identified.
The unnamed creek at RM 213.0 is relatively short (approximately 3 miles), and although no
definitive barriers to adult salmon passage were identified above PB213.0A, little if any adult
salmon spawning habitat exists due to steep gradients and the limited water depths.
2.7. Discussion and Conclusion
The mainstem Susitna River between RM 150 and RM 227 is moderately confined, lying within
an incised valley or canyon for most of its length. Where a limited floodplain exists, smaller
tributaries generally have a short reach of relatively low-gradient streambed. This abruptly
changes to a steep gradient when the tributary stream reaches the valley or canyon walls. These
high-gradient sections are where 100 percent of the barriers were identified during the study.
While some streams had multiple barriers, the first fish passage barrier was within 0.5 mile of the
Susitna River confluence for a majority of the tributaries.
Larger named tributaries such as Kosina Creek, Watana Creek, and Fog Creek were observed to
have their own incised valleys or canyons intersecting the main Susitna valley, resulting in less
steep gradients than smaller streams. Four of the 11 named major tributaries (Cheechako, Devil,
Tsusena, and Deadman creeks) have mainstem passage barriers, all of which were previously
known and confirmed during the assessment. In general, the results of the study indicated that
the larger the tributary, the farther upstream the barrier was located if one existed. Tsusena Creek
falls, located 3.8 miles upstream from the mainstem Susitna River confluence, is the upstream-
most barrier that was identified within the study area.
Above the proposed dam site, three Susitna River tributaries contain definitive fish passage
barriers within the inundation zone (i.e., below an elevation of 2,050 feet) of the proposed
Project. The barriers on two of these tributaries (RM 194.9 Creek and RM 200.7 Creek) are
located below the maximum elevation of the inundation zone. Therefore, under certain Project
conditions, access to previously inaccessible aquatic habitat (a total of 12 miles) would be
available. The definitive barrier on Deadman Creek is below the operational zone of the
proposed Project, and therefore would be inundated permanently, providing year-round access to
approximately 44 miles of previously inaccessible aquatic habitat. Cascade and boulder riffle
habitat types predominate above the falls for approximately 3 miles before gradients permit
run/glide habitat of any significance.
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3. AQUATIC HABITAT M APPING STUDY
The Aquatic Habitat Mapping Study was initiated in 2012 to begin characterizing aquatic habitat
within the mainstem Susitna River and selected tributaries above Devils Canyon (approximately
RM 154) upstream to and including the Oshetna River (RM 233.5). Information regarding
aquatic habitat, and specifically, habitat within the inundation zone, will provide data relevant to
establishing an environmental baseline to evaluate potential Project-related effects to fish and
their habitat.
3.1. Study Objectives
Specific Aquatic Habitat Mapping Study objectives included the following:
Develop and implement a habitat mapping approach to characterize Susitna River
tributaries above Devils Canyon upstream to and including the Oshetna River.
Characterize the type and amount of aquatic habitat within the reservoir inundation zone
below an elevation of 2,200 feet.
Collect aerial video imagery of the mainstem and Upper River tributaries to determine
the feasibility of using aerial video to complement ground-based habitat surveys.
3.2. Study Area
The study area for the Aquatic Habitat Mapping Study primarily included the mainstem Upper
Susitna River (Upper River) and its tributary streams above Devils Canyon upstream to and
including the Oshetna River (approximately RM 154 through RM 233.5) (Figure 3). In study
tributaries, the study area extended from the confluence with the mainstem Susitna River
upstream to an elevation of 3,000 feet. Within the reach of the mainstem Susitna River that
represents the proposed reservoir inundation zone (RM 184.3 to RM 230.9), the study area
extended to an elevation of 2,200 feet.
The study area for the aerial video component of the Aquatic Habitat Mapping Study extended
beyond the Upper River to include the mainstem Middle Susitna River (Middle River; RM 98.0
to RM 184) and a short section in the mainstem Lower Susitna River (Lower River) from
approximately (RM 65 to RM 81).
3.3. Methods
3.3.1. Aquatic Habitat Characterization and Mapping
Previous aquatic habitat work performed by ADF&G in the 1980s (ADF&G 1981b, 1983) and
more recently by ADF&G (Buckwalter 2011a) in the Upper River basin have yielded limited
habitat information. As such, uncertainties with a respect to the quality and quantity of habitat
information to support fishery resources remain a central issue. Factors contributing to the lack
of available information include a general lack of need (prior to licensing), access challenges,
and the relatively large geographic area.
In order to characterize aquatic habitat at an informative level of resolution and over a broad
geographic area in support of the Aquatic Habitat Mapping Study, the Aquatic Technical
Workgroup (ATWG), in coordination with AEA and licensing participants, developed a multi-
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faceted mapping approach that included a combination of aerial and ground-based aquatic
mesohabitat mapping methodologies.
Aerial Habitat Mapping (Video)
Use of aerial video is a valuable tool for conducting aquatic habitat mapping studies in the Upper
River watershed due to the watershed’s large geographic area, rugged terrain, and remoteness.
The video footage will be used to type stream habitat to the mesohabitat level in study area
tributaries that have open canopies and are clearly visible from the air (i.e., have elevational
accessibility required to collect imagery of sufficient resolution). The aerial habitat mapping
approach is meant to complement the ground-based mesohabitat approach. Collecting a
comprehensive mesohabitat dataset for the study area would be extremely difficult, if not
impossible, via the implementation of only one of the above methods.
When shot with a professional high definition (HD) camera from a helicopter at slow speeds (15
to 40 miles per hour [mph], depending on stream size), low altitude (75–300 feet), under good
lighting conditions, good water clarity, and a fairly open canopy, the video provides an up-close
and panoramic view of all of a stream’s features. Under these conditions, an experienced
observer can effectively discern mesohabitat types (e.g., riffles, runs, pools, etc.) and classify
channel character, dominant substrate, woody debris, and riparian vegetation. Use of aerial
video for habitat mapping can be enhanced with on-screen integration using a GPS. Figures 19
and 20 provide example screen captures from aerial video footage taken in an Upper River
tributary and the mainstem Middle River.
For the Aquatic Habitat Mapping Study, aerial video was shot from the right rear location of a
Robinson 44 helicopter with its right rear door removed. An HD Cannon XF 100 video camera
was fitted with a shoulder and pistol mount brace for maximum camera stability and a polarizing
lens to improve visibility below the water surface. The videographer was an experienced
fisheries biologist with 25 years of experience mapping aquatic habitat using the aerial video
methodology. A narrator/navigator sat in the left front seat of the helicopter next to the pilot.
From these positions, the pilot and the videographer had the same view of the stream and from
the front seat the narrator/navigator had a full view of the stream as well as an overall view of the
landscape. Optimum helicopter attitude, speed, and height above ground for best video results
were continually communicated to the pilot by the videographer over the ship’s intercom system.
All conversations on the helicopter intercom system between the survey crew were recorded onto
the video.
Tributaries were generally flown at a speed of 12 to 18 mph and at a height of 75–150 feet above
ground (AG). Speed and height of the helicopter varied, depending on factors such as the width
of the stream corridor, the height and narrowness of the canyon, and the height of trees in the
riparian zone. At split channels where the overall stream width was wider than the field of view
at the preferred survey elevation, one split channel was flown first and the pilot circled back to
fly the remaining channel.
Mainstem Susitna River sections were flown at a speed of 30 to 40 mph and at a height of 250 to
300 feet AG. Higher AG surveys in the mainstem Susitna River were conducted in order to
capture single channel sections with one pass.
All surveys were conducted in an upstream direction (with the exception of Kosina Creek, due to
excessive water surface glare). Upper River tributaries were videotaped from their confluence
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with the mainstem to a stream elevation of approximately 3,000 feet. Only Devil Creek was
videotaped a shorter distance. Devil Creek was flown only to the impassable barrier at
approximately RM 2.2, which would not be inundated by the Watana Dam pool.
Videotaping of the mainstem Susitna River and tributaries was scheduled in early September to
coincide with late summer base-flow conditions, high water clarity, leaf drop, and the possibility
of a sustained high pressure, clear weather window.
Ground-Based Habitat Survey
Ground-based habitat surveys were employed in order to (1) identify and characterize the length
of potential anadromous salmon and resident fluvial/adfluvial fish habitat in target streams below
an elevation of 3,000 feet; and (2) to characterize stream habitat in the proposed reservoir
inundation zone (RM 184.3 to RM 230.9) below an elevation of 2,200 feet.
Geomorphic Reach Determination
Each stream where ground-based habitat surveys were conducted was first divided into
geomorphic reaches based on changes in channel confinement, stream gradient, dominant
substrate size, or the distribution of flow (presence of tributaries or distributaries). Once the
stream was divided into geomorphic reaches, a subsection of each reach could be ground-truthed
using the habitat characterization methods described below to determine the frequency of
distribution of habitat units within each reach, thus precluding the need to ground-truth the entire
reach.
Habitat Surveys
Habitat surveys for subsections of each geomorphic reach were conducted by a two-person field
team starting at the downstream end of a reach and walking in an upstream direction. A GPS
point was collected at the downstream location or starting point for a reach. Habitat units were
mapped to the mesohabitat level (i.e., run, pool, riffle; Table 2), in accordance with the channel
typing and aquatic habitat classification system developed by the Fish and Aquatics TWG. Each
time a new mesohabitat unit was characterized during reach surveys, a GPS data point was
recorded in order to designate the upstream end of the existing mesohabitat unit and starting
point of the new mesohabitat unit (i.e., there may be multiple mesohabitat units within a reach).
Ground-based surveys also collected macrohabitat data in each mesohabitat unit including
channel and stream bank characteristics, large woody debris, cover/riparian vegetation, and the
presence of seeps.
Channel Characteristics
Mesohabitat unit length (m) was measured in the field with a laser rangefinder or visually
estimated when necessary. For mesohabitat units with lengths requiring more than one
measurement, various landmarks were identified and distances to and from these landmarks were
measured and summed at the top of the unit. In order for a mesohabitat unit to be classified as a
distinct unit, it needed to be at least one channel width long, otherwise it was combined with an
adjacent mesohabitat unit, regardless of its mesohabitat characterization.
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Channel type was recorded as either mainstem or side channel, which also included off-channel
habitats such as percolation channels and beaver complexes. Channel location in the stream was
recorded for each mesohabitat unit. In the simplest scenario, if the unit was located in the
mainstem then the location was center of the stream or if the unit was located in a side channel
then the direction of the side channel facing downstream was recorded, either left or right. Side
channels were surveyed to the same mesohabitat level as the adjacent mainstem, with the same
habitat parameters collected.
Maximum depth (measured in scour pools and backwater pools) and pool crest depth (measured
in scour pools only) were measured in meters (m). Average maximum depth (m) was recorded in
each non-pool mesohabitat unit by taking the average of at least five measurements. All depth
measurements were measured using a calibrated trekking pole.
Wetted width represents the lateral distance from the watered edge from one bank to the opposite
stream bank. Wetted width (m) was measured at a representative point along the mesohabitat
unit that was neither the narrowest nor the widest point across the stream. Bankfull width (m)
represents the lateral extent of the water surface elevation perpendicular to the channel at
bankfull depth (average vertical distance between channel bed and estimated water surface
elevation required to completely fill the channel to a point above which water would enter the
floodplain or intersect a terrace or hill slope). Both wetted and bankfull widths were measured
with a laser rangefinder or with a calibrated trekking pole. In some instances, wetted and
bankfull widths were visually estimated, if the laser rangefinder was not working and if the
stream could be safel y waded.
Stream gradient (in degrees) was measured with a laser rangefinder or with a clinometer (in
percent) in each mesohabitat unit. All gradient measurements were converted to percent, if
needed, at the end of the field day.
Substrate types were estimated by visual identification based on the U.S. Department of
Agriculture, Forest Service (USFS; 2001) classification (See Table 3). For each mesohabitat unit,
each substrate category was estimated to the nearest 10 percent.
Stream Bank Characteristics
The amount of undercut bank (UCB) on each side of the stream was estimated to the nearest
percent (total amount of qualifying UCB/total length of mesohabitat unit) for each mesohabitat
unit. A bank was considered undercut if the undercut was greater than or equal to 0.3 meters (12
inches) incised into the bank and greater than 1.0 meters (39 inches) long. All undercut banks
contained within the channel up to bankfull height were measured even if they were above the
surface of the water at the time of the survey (USFS 2001).
The percentage of bank side erosion on each bank was estimated based on bank sloughing. In
order for a portion of a stream bank to be evaluated for erosion, it had to be greater than 1.0
meter in length. Percentage was determined the same way as UCB.
Large Wood, Cover, and Riparian Vegetation
The amount of large woody debris (LWD) observed was counted for each mesohabitat unit. To
be classified as LWD, a piece of wood must have been at least 0.1 meter (4 inches) in diameter
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and at least 1.0 meter (39 inches) in length with at least 1.0 m of the wood below the water’s
surface at bankfull flow (USFS 2001).
The dominant riparian vegetation class was recorded for each mesohabitat unit based on the
USFS (2001) classification (Table 4).
All stream cover types (see Table 5) were lumped together and collected as a whole because this
study was not aimed at identifying cover for any one species or any specific life stage of an
individual species. The percentage total cover was estimated by determining how much cover for
all species and all life stages of fish was present in each mesohabitat unit. Percent cover in the
unit was estimated (rounded to the nearest 5 percent) once the survey crew reached the top of the
mesohabitat unit.
3.3.2. Data Analysis
The goal for the aerial video analysis in 2012 was to determine the feasibility of using this
method for detailed habitat mapping purposes in future studies. All video footage was reviewed
for clarity and definition of mesohabitat types and whether the different mesohabitat types could
be reliably discerned from each other. Mesohabitats will be typed using aerial video in 2013
according to methods described in the Revised Study Plan (RSP) Section 9.9, Characterization
and Mapping of Aquatic Habitats in the Susitna River with Potential to be Affected by the
Susitna-Watana Project.
For all ground-based surveys, all mesohabitat characterization data, including GPS information,
were uploaded to a GIS database and plotted. In addition to each reach being measured on the
ground, total reach lengths were measured in kilometers (km) using GIS. Lines connecting each
mesohabitat unit were then digitized as a GIS shapefile representing the distribution of
mesohabitat units in surveyed creeks. All data were visually QC checked to identify and address
any anomalous spatial data. Anomalous data points were visually moved to the stream
centerline.
The relative frequency of each mesohabitat unit type based on length was calculated. The
frequency of each mesohabitat type was also calculated. Total weighted average wetted width
and bankfull width were calculated by taking the total average wetted width and the total average
bankfull width for each mesohabitat unit and weighting them by the total length for each
mesohabitat unit.
3.3.3. Data Review and Quality Control
At the end of each day of collecting aerial video, files were reviewed for completeness, named
according to Project guidelines, and cataloged. Duplicate video files were also made and backed
up to two portable hard drives. The two hard drives were kept in different locations until all data
were transferred to HDR’s Anchorage server. Video files were post-processed to MPEG 4 video
format with an on-screen information panel inserted that displays continuous river mile, GPS
coordinate, and video time stamp. The video files will be further integrated with the Project GIS
database. Upon completion of video post-processing, the video files will be made available to
the public through AEA.
During ground-based surveys, data collected for each mesohabitat unit were reviewed upon
completion of the habitat characterization. This review ensured that all habitat parameters were
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collected and that recorded values were reasonable. Notes were made to document instances
when data could not be collected. All data were recorded and stored in a Juniper Archer hand-
held computer with an internal GPS. The GPS provided a latitude and longitude position for each
point collected. Field forms were taken into the field each day in the event of an Archer
malfunction in addition to a backup Archer. The data were downloaded nightly to the field office
laptop in a specific folder for each day. All data were backed up on each Archer hand-held
computer and the field laptop after completion of a QC I review to verify the accuracy of the data
(before leaving the field and nightly). If the data were entered directly into the Archer hand -held
computer, no QC II was conducted on the data because QC II involved checking the original
datasheets against the database. In the Anchorage office, a QC III review was performed on the
GIS database by a senior professional before submitting the database to AEA. QC IV (database
verification) and V (database verification by senior-level professional before analysis for reports)
reviews will occur outside of HDR.
3.4. Deviations from Study Plan
Throughout the field season, there were several deviations from the 2012 Upper Susitna River
Fish Distribution and Habitat Study Plan. These deviations were attributable to a variety of
factors including weather, logistics, and field conditions that often precluded proposed methods.
Furthermore, several habitat parameters were added prior to the field effort (i.e., bank side
erosion, total percent cover, channel type, and channel location). Deviations are described in
detail below.
3.4.1. Video-Based Deviations
There were no deviations in field videography methods from the 2012 Upper Susitna River Fish
Distribution and Habitat Study Plan (AEA 2012).
3.4.2. Ground-Based Deviations
Changes to the 2012 ground-based habitat activities included the following:
Parallel mesohabitats were not recorded during ground-based habitat surveys on Jay,
Watana, and Kosina creeks due to the presence of deep water and high velocities, which
created unsafe wading conditions.
In order to provide more detail, a relative percentage of each substrate category (Table 3)
rounded to the nearest 10 percent was recorded instead of just dominant and subdominant
substrate composition in each mesohabitat as identified in the Study Plan.
UCB was recorded as a relative percentage across the whole mesohabitat unit for each
bank instead of being measured to the nearest meter.
Additional habitat parameters were collected for each mesohabitat unit that included
stream gradient, wetted width, bankside erosion, stream cover, and dominant riparian
vegetation classifications.
Mainstream, side-channel, off-chanel designations were recorded for each mesohabitat
unit to differentiate between mainstem and side channel mesohabitat units. Each
mesohabitat unit was also assigned a location within the channel.
Ground based mapping was intended to cover approximately 20 percent of the area
covered by video for the three targeted streams: Watana Creek, Jay Creek, and Kosina
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Creek. Ground sampling this amount of the video coverage was not accomplished due to
inaccessibility in steep canyon reaches, the lack of suitable helicopter landing zones, and
inclement weather. Groundmapping amounted to 8% of Watana Creek, 15% for Kosina
creek and 14% for Jay Creek.
Video coverage of three target tributaries— Watana Creek, Jay Creek, and Kosina
Creek—was expanded to include a total of 12 major tributaries in the study area.
Addition aerial videos were also taken of the Middle River and Upper River main
channel reaches. This additional coverage was added to aid in the development of
sampling approaches for the RSP. The time-based method for mesohabitat frequencies
was applied to the expanded set of tributaries and line mapping was performed for main
channel areas as described in the RSP. These analyses were conducted in December
2012 and January 2013 and are reported in Appendix E of the Fish Distribution
Implemention Plan filed with FERC on January 31, 2013.
The time-based frequency method was not applied to mapping woody debris or riparian
vegetation from aerial videos.
3.5. Results
3.5.1. Aerial Habitat Mapping
Aerial video was collected over a period of 6 days from September 7 to September 12, 2012
during optimal conditions and preceded a major flooding of the Susitna River in mid-September.
Although the study area for the 2012 Aquatic Habitat Mapping Study as identified in the Study
Plan was the Susitna River above Devils Canyon, the aerial video surveys were expanded to the
Middle River (RM 98.0–184) and Lower River (RM 65–81) segments.
Conditions for aerial videotaping of Upper River tributaries and the mainstem of the Upper and
Middle River were excellent. Both tributary and mainstem flows were at late summer seasonal
lows. Tributary flows were clear with visibility of bottom substrate to depths of 2–4 feet.
Mainstem flows were in the range of 10,000 to 12,000 cubic feet per second (cfs) with visibility
of approximately 1 foot. Lighting was generally excellent. However, the low angle and southern
position of the sun created some difficulties with glare when flying in a southerly direction. This
problem was overcome by flying two tributaries—Kosina Creek and a tributary of Fog Creek—
in a downstream direction. Swirling winds were also a problem on a few tributaries. Two and
three passes of river sections were frequently necessary in the Middle River where split main
channels, side channels, and side sloughs are common. Table 88 is a list of tributaries and
mainstem sections videotaped in 2012.
Review of video of Upper River tributaries and the mainstem Upper and Middle River segments
demostrated that the video footage has sufficient quality for mesohabitat typing of the aerial
video coverage area. Mesohabitat types are most discernible using video in the Upper River
tributaries where individual mesohabitat types are more clearly defined. In the mainstem Upper
River and Middle River, low gradients make mesohabitat types less distinct from one another,
and therefore are less definable, whether observed from the ground or from the air. For example,
from the air and because of poor water clarity in the mainstem, it is sometimes difficult to
distinguish between a run and a riffle or a pool and a glide. The purpose of ground-truthing the
aerial video mapping, as described in the RSP, is to confirm or modify the aerial video mapping
based on evidence on the ground.
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In addition to conducting aerial video surveys of Upper River tributaries and the mainstem of the
Upper and Middle River, test video was collected of the Lower River between RM 65 and RM
81 to determine the practical and technical application of aerial video for habitat characterization
in this 1-mile-wide and highly braided reach of the river (Figure 21). A 16-mile section of the
river was selected extending from RM 65 to RM 81 for the feasibility assessment. The test
section was flown at three different heights AG. The number of parallel flight paths necessary to
cover the river width at the three different elevations was as follows: one path at 2,650 feet AG;
two paths at 1,700 feet AG; and four paths at 400 feet AG.
The test showed that a height of 400 feet or lower with three to five flight paths would be
necessary to visually differentiate mesohabitat types in the Lower Susitna River segment.
Further, several parallel paths would be extremely difficult to track even with the use of GPS and
would be very difficult to follow during review of the video. In summary, review of the test
section concluded that aerial videotaping would not be a practical method for habitat mapping
the Lower River reach.
In summary, review of the test section concluded that aerial videotaping is not a practical method
for habitat mapping the Lower River reach. Development of mapping methods for this section of
river should wait until results of the 2012 interim studies are reviewed and analyzed by the
Technical Workgroups (TWGs); in particular the hydrologic study. At that time, the habitat
characterization objectives for the Lower River will be more clearly defined and a
complementary methodology can be developed.
3.5.2. Ground-Based Habitat Mapping
Jay Creek
Jay Creek was broken into seven unique geomorphic reaches (Figure 4). Based on GIS
analysis, the length of Jay Creek below the 3,000-foot elevation is 21.7 km. Approximately 2.05
km (9.4 percent) was ground-surveyed by two field crews on September 17, 2012. Results of the
ground-based habitat surveys for each geomorphic reach are provided below.
Geomorphic Reach 1
Jay Creek Geomorphic Reach 1 is approximately 1.4 km long (Figure 5). The lower 543 m (39
percent) of the reach was ground-truthed. The majority of the segment mapped was in the
mainstem (443 m) with the rest being side channel mesohabitat (100 m). In this reach, the main
channels were comprised of six riffle and nine run mesohabitat units with a similar relative
frequency of riffles (54.9 percent) and runs (45.1 percent; Table 6). Overall, side channels had a
greater diversity of mesohabitat types, with one cascade, three riffles, three runs, one scour pool,
one backwater pool, and one slough (Table 9).
Bank erosion on the left bank was greater the right bank in the side channels than in the
mainstem and similar on the right bank (Table 6 and Table 9). As expected, the mainstem had
greater total average bankfull and wetted widths than the side channels. There was minimal
difference between stream gradient and average maximum depth between mainstem and side
channel mesohabitats (Table 6 and Table 9).
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The frequency of LWD was greater in side channels than in mainstem mesohabitats (Table 6 and
Table 9). There was no clear pattern in the amount of UCB observed in Jay Creek Geomorphic
Reach 1. The mainstem had a much greater amount of UCB on the right bank, while the side
channels had a much greater amount of UCB on the left bank (Table 6 and Table 9).
Side channel mesohabitats in this reach had approximately twice the average cover as mainstem
mesohabitats (Table 6 and Table 9). Both channel types were primarily composed of nonforest
shrub willow dominant riparian vegetation (Table 7 and Table 10). Substrate was not estimated
for this reach (Table 8 and Table 11).
Geomorphic Reach 2
Jay Creek Geomorphic Reach 2 is approximately 1.3 km long (Figure 6). Due to helicopter
inaccessibility, activities to ground-truth the reach began in the middle of the reach and worked
toward the upstream end. The ground-truthed portion of Reach 2 was approximately 0.78 km
long (~60 percent) and was divided into nine mesohabitat units (comprised of four riffles and
five runs) in the mainstem. No side channels were present in the sampled reach. The riffles
comprised 16.2 percent (126 m) by length of the mapped mesohabitats, while the runs comprised
83.8 percent (650 m) by length of the mapped mesohabitat units (Table 12).
The total average weighted wetted width was the same between riffles and runs, while the total
average weighted bankfull width was greater in runs than in riffles (Table 12). Average stream
gradient and the total weighted average maximum depth were similar between riffles and runs.
Very little UCB was observed in this reach. On average, the riffles had much less erosion on the
left bank than on the right bank; however, for runs, the bankside erosion was relatively the same.
Also, right bank erosion in the riffles was relatively similar to the amount of erosion within runs
(Table 12).
On average, runs had much more LWD than riffles. Percent cover was not recorded in this reach
(Table 12). Riparian vegetation type in this reach included nonforest shrub willow dominant,
nonforest shrub alder dominant, and broadleaf forest-closed canopy (Table 13). As expected,
riffle and run mesohabitats in this reach were dominated by larger-size substrate with
approximately 60–70 percent being comprised of boulder and cobble. Gravel was also present
(26–30 percent) and small amounts of sand/silt (Table 14).
Geomorphic Reaches 3 - 5
Jay Creek Geomorphic Reach 3 is approximately 1.5 km long; Reach 4 is approximately 1.4 km
long; and Reach 5 is approximately 1.0 km long. Due to helicopter inaccessibility and inclement
weather, Geomorphic Reaches 3–5 were not sampled.
Geomorphic Reach 6
Jay Creek Geomorphic Reach 6 is approximately 6.3 km long (Figure 7). The middle 0.67 km
(~11 percent) of the reach was ground-truthed. There were five mesohabitat units in the
mainstem, one riffle, three runs, and one scour pool and five mesohabitat units in the side
channel, one riffle, two runs, one scour pool, and one backwater pool (Table 15 and Table 18).
More length of stream was mapped in the mainstem than in the side channels (589 m in the
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mainstem and 98 m in the side channels). There was a greater diversity of mesohabitat types
present in the side channels than in the mainstem. Runs accounted for the greatest habitat length
in both the mainstem (93.2 percent) and side channels (65.3 percent; Table 15 and Table 18).
Total weighted average wetted width and bankfull width were much greater in the mainstem
channel than in side channels. In general, the mainstem mesohabitats were much deeper than side
channel mesohabitats. Average weighted stream gradient was similar in both side channels and
mainstem mesohabitats in this reach (Table 15 and Table 18).
There were greater amounts of bankside erosion and LWD in the mainstem mesohabitat types;
however, there were almost equal amounts of UCB.
Percent cover was not recorded in this reach (Table 15 and Table 18). For both channel types,
riparian vegetation was primarily composed of willow although mainstem channel habitats
included closed and open conifer forest canopy types (Table 16 and 19). Regardless of channel
type, riffle and run mesohabitats in this reach were primarily composed of boulder, cobble, and
gravel. In pool mesohabitats, a more diverse and even distribution of substrate types was
available. Cobble and gravel were the dominant substrates in these mesohabitats and higher
concentrations of sand/silt and organic material were also available (Table 17 and 20).
Geomorphic Reach 7
Jay Creek Geomorphic Reach 7 is approximately 8.8 km long, from the end point of Geomorphic
Reach 6 to the 3,000-foot elevation mark. This reach was not sampled due to helicopter
inaccessibility and inclement weather.
Kosina Creek
Kosina Creek was divided into eight unique geomorphic reaches (Figure 8), based on the
methods described above. Once better imagery for the Upper River basin is available, some of
these reaches may be combined. Based on GIS measurements, Kosina Creek is approximately
29.3 km in length below the 3,000-foot elevation. Of the total river length below 3,000 feet,
approximately 6.4 km (22 percent) were ground-truthed. Kosina Creek was ground-surveyed by
two field crews on September 11, 12, and 14, 2012, from late morning through early evening.
Detailed information for each reach that was ground-truthed is provided below.
Geomorphic Reach 1
Kosina Creek Geomorphic Reach 1 is approximately 2.7 km long (Figure 9). The lower 1.7 km
(~63%) of the reach was ground-truthed. There were 11 mainstem mesohabitat units, comprised
of six riffles and five runs (Table 21). There were a total of 22 side channel mesohabitat units
and one off-channel mesohabitat unit. While there was almost two times as much length of riffle
versus run mesohabitat, the frequency of each mesohabitat was similar. Almost the same amount
of side channel mesohabitat was mapped as mainstem mesohabitat, although a greater diversity
of mesohabitat types (six types) was present in the side channels (Table 21 and Table 24).
The average stream gradient for all mesohabitat units was 2.0 percent (Table 21 and Table 24).
The average maximum depths in the mainstem were much deeper than in the side channels
(Table 21 and Table 24).
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No bankside erosion was observed in either the mainstem or side channel mesohabitats.
Minimal LWD was observed in the side channels, and none was observed in the mainstem. No
UCBs were observed in the mainstem with minimal amounts observed in side channels.
Total cover was not recorded for any of the mesohabitat units in this reach (Table 21 and Table
24). The majority of the riparian vegetation in the mainstem and the side channel mesohabitat
units was nonforest shrub (alder and willow; Table 22 and Table 25). Regardless of channel
type, riffle and run mesohabitats in this reach were primarily composed of boulders and cobbles
with smaller amounts of very large or small substrate types (Table 23 and 26).
Geomorphic Reach 2
Kosina Creek Geomorphic Reach 2 is approximately 1.0 km long (Figure 10), and approximately
0.6 km (~60 percent) of the reach was ground-truthed. There were six mainstem mesohabitat
units (one scour pool, two riffles, and three runs) totaling approximately 545 m. There was one
side channel mesohabitat unit (riffle/pocketwater), which was 55 m long (Table 27 and Table
30).
Average stream gradient was 2.0 percent for all mesohabitat units. Mainstem mesohabitat depths
were much greater than side channel values (Table 27 and Table 30).
There was no bankside erosion or UCB in the reach. On average, each mainstem mesohabitat
unit contained one piece of LWD.
Total cover was not recorded for any of the mesohabitat units in this reach (Table 27 and Table
30). All the riparian vegetation in the mainstem and side channel mesohabitat units was
nonforest shrub. Willow was the dominant riparian vegetation in the mainstem and alders were
dominant in the side channels (Table 28 and Table 31). Boulder was the dominant substrate type
for mesohabitats in this reach (Table 29 and 32).
Geomorphic Reach 3
Kosina Creek Geomorphic Reach 3 is approximately 7.2 km long (Figure 10). Approximately
0.5 km (approximately 7 percent) of the reach was ground-truthed. Three mesohabitat units were
mapped in the mainstem of Reach 3 (two riffles and one run; Table 33). In side channels, eight
mesohabitat units were ground-truthed (two riffles, one riffle/pocketwater, three runs, and two
runs/pocketwater; Table 36).
There was no bankside erosion in any of the mesohabitat units. There was an average of two
pieces of LWD per mesohabitat unit in both the mainstem and the side channels. There was no
UCB in the mainstem and a small amount on both banks of the side channels.
Total cover was not recorded in this reach (Table 33 and Table 36). In the mainstem, almost
equal amounts of riparian vegetation was broadleaf forest open and nonforest shrub willow,
while in the side channel, most of the riparian vegetation was nonforest shrub willow (Table 34
and Table 37). Boulder was the dominant substrate type for mesohabitats in this reach (Table 35
and Table 38).
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Geomorphic Reach 4
Kosina Creek Geomorphic Reach 4 is approximately 1.4 km long (Figure 11), and approximately
0.9 km (~64 percent) of the reach was ground-truthed. Eight mainstem mesohabitat units were
mapped in the mainstem channel consisting of one cascade, two riffles, three riffles/pocketwater,
one run, and one run/pocketwater. There were no side channels in this reach, but there was one
off-channel mesohabitat (percolation channel; Table 42). Most of the mainstem was composed
of riffle habitat (Table 39).
Excluding the cascade, the average stream gradient in the mainstem and the side channel was 2.0
percent. Once the cascade was factored in, the average mainstem stream gradient increased to 3.0
percent (Table 39).
More bankside erosion and UCB were present in the mainstem than in the percolation channel.
No LWD was observed in the reach.
Total cover was greater in the mainstem than in the percolation channel (Table 42). All the
riparian vegetation was nonforest shrub willow in the mainstem and in the off-channel
mesohabitats (Table 40 and Table 43). In general, mainstem mesohabitat types contained an
even distribution of boulder, cobble, and gravel substrate types (Table 41), while the percolation
channel was dominated by gravel and sand/silt substrates (Table 44).
Geomorphic Reach 5
Kosina Creek Geomorphic Reach 5 is approximately 0.5 km long (Figure 10). Approximately
0.5 km (100 percent) of the reach was ground-truthed. Mainstem mesohabitat units consisted of
one riffle, one riffle/pocketwater, and two runs. There was also one side channel run.
Average stream gradient was the same between all mesohabitat units in the reach (Table 45 and
Table 48).
More bankside erosion was observed in mainstem versus side channel mesohabitats. No LWD
or UCB was recorded in either the mainstem or the side channel.
The side channel had a greater percentage of total cover (Table 45 and Table 48). The mainstem
mesohabitat units had riparian vegetation that consisted of nonforest shrub willow and the side
channel had riparian vegetation that consisted of nonforest shrub alder (Table 46 and Table 49).
In mesohabitat types of this reach, all substrate types, with the exception of organic material,
were present (Table 47 and Table 50).
Geomorphic Reach 6
Kosina Creek Geomorphic Reach 6 is approximately 0.4 km long (Figure 12). In this reach, the
entire reach channel was ground-truthed. Mainstem channel mesohabitat units consisted of one
riffle and two runs. There were no side channel or off-channel mesohabitat units in this reach
(Table 51).
Stream gradient was the same for all mesohabitat units in the reach (Table 51). Average
maximum depth was not recorded due to safety concerns.
Runs had a greater amount of streambank erosion than riffles. No LWD or UCB was present in
any of the mesohabitat units. Total cover for the riffle was 20 percent.
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Total cover for the two runs was 30 and 50 percent (Table 51). Riparian vegetation in the reach
was primarily composed of nonforest shrub willow (Table 52). Mesohabitat types in this reach
(riffle and run) were primarily composed of boulder, cobble, and gravel, although sand/silt was
also present in small amounts (Table 53).
Geomorphic Reach 7
Kosina Creek Geomorphic Reach 7 is approximately 2.0 km long (Figure 12). Approximately
0.8 km (~40%) of the reach was ground-truthed. Mainstem mesohabitat units consisted of one
riffle and two runs. Side channel and off-channel mesohabitat types consisted of one percolation
channel, one scour pool, seven runs, and one slough (Table 54 and Table 57).
The average stream gradient for the mainstem and the side channels was the same. The laser
rangefinder malfunctioned and lengths, widths, and stream gradients could not be recorded for
many of the mesohabitat units in this reach (Table 54 and Table 57).
The side channels had a greater amount of bankside erosion. No LWD was observed in either the
mainstem or the side channels. The amount of UCB was slightly more in mainstem mesohabitats
(Table 54 and Table 57).
Total coverage was greater in side channel versus mainstem mesohabitat types (Table 54 and
Table 57). Due to a faulty laser rangefinder the actual lengths of the mesohabitat units were not
recorded, but in both the mainstem and the side channel mesohabitats, nonforest shrub willow
was the dominant riparian vegetation type (Table 55 and Table 58). As expected, riffle and run
mesohabitats in the mainstem channel were dominated by larger, more hydraulically stable
substrate types (i.e., boulder and cobble) while side channel substrates were primarily composed
of gravel, sand/silt, and organic material (Table 56 and Table 59).
Geomorphic Reach 8
Kosina Creek Geomorphic Reach 8 is approximately 14.1 km long below the 3,000-foot
elevation mark (Figure 13). Approximately 1.0 km (~7 percent) of the reach was ground-truthed.
Mainstem mesohabitat units consisted of one riffle and two runs (Table 60. The side channel
mesohabitat units consisted of one riffle and two runs.
Average depth was about twice as deep in the mainstem as in the side channels. In this reach,
there was no bankside erosion (Table 60 and Table 63).
LWD was not observed in any of the mesohabitat units. There was more UCB in the mainstem
than in side channel habitat. Total cover was not recorded in this reach (Table 60 and Table 63).
The riparian vegetation in both the mainstem and side channel mesohabitats was dominated by
nonforest shrub willows (Table 61 and Table 64). Riffle and run mesohabitats of both channel
types were bedrock- and/or boulder-dominated (Table 62 and Table 65).
Watana Creek
Watana Creek was divided into eight distinct geomorphic reaches (Figure 14) based on the
methods described above. Once better imagery for the Upper River basin is available, some of
these reaches may be collapsed into each other. Watana Creek is approximately 33.9 km long
below the elevation of 3,000 feet, and 2.262 km (~7 percent) were ground-truthed. It was
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ground-surveyed by two field crews on September 13, 2012, from late morning through early
evening. Detailed information for each reach that was ground-truthed is provided below.
Geomorphic Reach 1
Watana Creek Geomorphic Reach 1 is approximately 1.0 km long (Figure 15). Approximately
0.9 km (~90 percent) of the reach was ground-truthed. Mainstem mesohabitat units were
composed of five riffles and five runs (Table 66). No side channels were surveyed in this reach.
Even though the total number of mapped habitats was equal between riffles and runs, the riffles
had a greater length of habitat.
The average wetted and bankfull widths were much greater in the riffles. The average maximum
depth was greater in the runs than riffles (Table 66).
Overall, there was a greater amount of UCB, LWD, and bankside erosion in the riffles than in the
runs.
Total cover was not recorded for this reach (Table 66). Riparian vegetation in the majority of the
mesohabitat units consisted of nonforest willow (Table 67). Mesohabitats in this reach were
primarily cobble substrate (Table 68).
Geomorphic Reach 2
Watana Creek Geomorphic Reach 2 is approximately 0.8 km long. Reach 2 was not ground-
truthed due to inclement weather (i.e., rain, fog, low visibility), which resulted in navigation and
access challenges.
Geomorphic Reach 3
Watana Creek Geomorphic Reach 3 is approximately 8.2 km long (Figure 16). Approximately
0.062 km (~1 percent) of the reach was ground-truthed. It consisted of one mainstem
mesohabitat unit (run) and one off-channel mesohabitat unit (percolation channel). The
mainstem run was approximately two times as long as the percolation channel (Table 69 and
Table 72).
Both mesohabitat units had nonforest shrub willow as their dominant riparian vegetation type
(Table 70 and Table 73). The run mesohabitat was comprised of equal concentrations of cobble
and gravel (40 percent) and sand/silt (20 percent) while the percolation channel had smaller
substrate types, primarily gravel and sand/silt (Table 71 and Table 74).
Geomorphic Reach 4
Watana Creek Geomorphic Reach 4 is approximately 3.4 km long (Figure 17). Approximately
0.6 km (~18 percent) of the reach was ground-truthed. Mainstem mesohabitat types consisted of
three riffles and two runs. There were also side channel and off-channel mesohabitat units
consisting of one beaver complex, one backwater pool, three scour pools, three riffles, one
riffle/pocketwater, one run, one run/pocketwater, and one slough (Table 78. Over twice as much
habitat was mapped in the mainstem; however, the diversity of mesohabitat units was much
greater in the side channels (Table 75 and Table 78).
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While the average stream gradient was the same between the mainstem and the side channels, the
average wetted and bankfull widths were much greater in the mainstem (Table 75 and Table 78).
Percent cover was greater in the mainstem, but bankside erosion, UCB, and LWD were very
similar between the mainstem and the side channels (Table 75 and Table 78). Side channels also
had a greater variety of riparian vegetation types (Table 76 and Table 79). Mainstem channel
habitat was primarily comprised of cobble and gravel substrate (Table 77). Substrate types in
side channel habitats were more diverse and included smaller material (sand/silt and organic
material; Table 80).
Geomorphic Reach 5
Watana Creek Geomorphic Reach 5 is approximately 0.3 km long. This reach was not ground-
truthed due to poor weather conditions, resulting in helicopter inaccessibility.
Geomorphic Reach 6
Watana Creek Geomorphic Reach 6 is approximately 9.9 km long (Figure 18). Approximately
0.7 km (~7 percent) of the reach was ground-truthed, which consisted of three riffles and two
runs in the mainstem channel (Table 81). Side and off-channel mesohabitat units were also
surveyed. They consisted of two percolation channels and two riffles (Table 84).
While the average stream gradient was the same between the mainstem and the side channels, the
average wetted and bankfull widths were much greater in the mainstem (Table 81 and 84).
Percent cover was greater in the side channel. Very little bankside erosion and UCB were
observed in either channel types. LWD was highest in run mesohabitats (Table 81 and 84).
Willow was the exclusive riparian vegetation type throughout the sampled reach (Table 82 and
Table 85). Mainstem channel habitat was primarily comprised of cobble and gravel with some
boulder substrate (Table 83) while side channel habitats were more diverse and trended toward
smaller material (sand/silt and organic material; Table 86).
Geomorphic Reach 7 and 8
Watana Creek Geomorphic Reach 7 is approximately 6.4 km long and Reach 8 is approximately
3.9 km long below the 3,000-foot elevation mark. These reaches were not ground-truthed due to
poor weather conditions, resulting in helicopter inaccessibility.
3.6. Discussion and Conclusion
3.6.1. Aerial Habitat Mapping
Excellent conditions (i.e., weather, low flow levels, clear water, and open canopy of stream
corridors) resulted in excellent video footage of all the primary tributaries in the Upper River, the
Upper River mainstem, and the Middle River mainstem. Post-field collection review of the video
footage determined that imagery collected via this methodology can be reliably used for
characterizing mesohabitat frequency and distribution in the Upper and Middle River mainstem
and its tributaries in combination with ground-based surveys. Use of the aerial video
methodology for this purpose will be undertaken in 2013 according to methods described in RSP
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Section 9.9, Characterization and Mapping of Aquatic Habitats in the Susitna River with
Potential to be Affected by the Susitna-Watana Project.
Test results in the Lower River mainstem demonstrated that the use of aerial video for
mesohabitat mapping in this reach was not feasible because of the multi-channel complexity and
mile-wide width of the river corridor.
3.6.2. Ground-Based Habitat Mapping
In 2012, the emphasis on ground-based mesohabitat mapping was to begin to characterize habitat
that has the potential to be altered by the Project. Given that there has never been a habitat
survey in the region, nothing was known about the types of mesohabitat units present and their
relative proportion in each stream. This information will support the establishment of an
environmental baseline to evaluate potential Project-related effects to fish and their habitat.
Jay, Kosina, and Watana Creeks
Overall, the mesohabitat type composition between main channel and side channels in all three
creeks surveyed appeared to be driven by the different hydrologic regimes that would be
expected within the two channel types. The dominance of riffle and run mesohabitat types in the
main channels of all surveyed tributaries is likely attributable to the prevalence of higher flows
and velocities, which create a greater potential for hydraulic disturbance. Habitat characteristics
in the mainstem channel mesohabitats were generally comprised of greater bankfull and wetted
widths, greater average maximum depths, larger substrates, and less LWD. Although main
channel riffle and run mesohabitat types appeared to make up a significant portion of the total
length of stream reach surveyed, side channels, when present, appeared to boast a greater
diversity of mesohabitat types. This greater diversity of mesohabitat types in side channels likely
results in an increase in overall habitat complexity. In side channels, the frequency of LWD,
cover, greater range of substrate including smaller materials, and overhanging vegetation was
more prevalent. The increased retention of elements that support habitat complexity is likely due
to a more stable hydrologic regime relative to main channel habitat.
In evaluating the results of the Aquatic Habitat Mapping Study as it relates to fisheries resources,
the study results indicate that in general, main channel and side channel habitats in the surveyed
tributaries function to support different life history stages of fish species present within the
Susitna River basin. Mains channel habitats, which are primarily composed of riffle and run
mesohabitats types, are better suited to support subadult and adult fish. The presence of higher
velocities in this channel type may create less suitable conditions for smaller fish, particularly at
high flows (McMahon and Hartman 1989). As such, main channel habitats may function as
migratory corridors and provide greater amounts of spawning habitat for certain species of fish.
Higher overall complexity within side channel habitats likely supports a greater variety of life
history stages for fish species in the basin. The greater availability of LWD and cover increases
productivity and the available food base for rearing. LWD creates refugia that may reduce
bioenergetic expenditure (due to lower velocities) and reduce predation of juvenile fish. Similar
to main channels, riffle habitat in side channels may support spawning adult fish. Although main
channel and side channel habitats may tend to support specific life history stages, the availability
of both types of channel-type habitats in tributary systems is critical to supporting the overall
health of fishery resources in the Susitna River basin.
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Lessons Learned
Due to the large geographic scope, remoteness of the study area, and prevalence of non-wadeable
streams, challenges in gathering data were experienced by the field crews. While most of these
difficulties arose out of safety concerns (e.g., stream wadeability, etc.), some were based on
logistical issues such as equipment malfunction and helicopter inaccessibility to specific areas
that required sampling. In order to support more efficient implementation of the 2013 study
program, all documented challenges were identified and communicated to the authors of the
RSP. Appropriate changes were made in the RSP to address these challenges prior to the
implementation of future studies.
4. REFERENCES
ADF&G (Alaska Department of Fish and Game) 1981a. Resident fish investigations on the
Upper Susitna River. Susitna Hydroelectric Project. Alaska Power Authority Document
No. 1425. Anchorage, AK.
ADF&G. 1981b. Subtask 7.10 Phase 1 Final Draft Report resident Fish Investigation on the
Upper Susitna River. Anchorage, Alaska. Prepared for: Acres American Incorporated,
Buffalo, New York.
ADF&G. 1983. Volume 5: Upper Susitna River Impoundment Studies 1982. Susitna Hydro
Aquatic Studies Phase II Basic Data Report. Anchorage, Alaska. Alaska Department of
Fish and Game.
ADNR (Alaska Department of Natural Resources), Division of Forestry. 2007. Alaska Forest
Resources and Practices Regulations.
AEA (Alaska Energy Authority). 2012. 2012 Upper Susitna River Fish Distribution and Habitat
Study Plan. Accessed online at http://www.susitna-watanahydro.org.
Buckwalter, J.D. 2011a. Synopsis of ADF&G’s Upper Susitna Drainage Fish Inventory, August
2011. November 22, 2011. ADF&G Division of Sport Fish, Anchorage, AK.
Buckwalter, J.D. 2011b. Anadromous Waters Catalogue. Nomination number 11-582. Accessed
January, 16, 2013.
http://www.adfg.alaska.gov/FDDDOCS/DOCUMENTS/NOM_PDFs/SCN/11-582.PDF
Buckwalter, J.D., J. M. Kirsch, and D. J. Reed. 2010. Fish Inventory and Anadromous
Cataloging in the Lower Yukon River Drainage, Alaska department of Fish and Game,
Fisheries Data Series No. 10-76. November 2010.
McMahon, T.E. and G.F. Hartman. 1989. Influence of cover complexity and current velocity on
winter habitat use by coho salmon (Oncorhynchus kisutch). Canadian Journal of
Fisheries and Aquatic Sciences 46:1551-1557.
Moore, K. M. S., K. K. Jones, and J. M. Dambacher. 2006. Aquatic Inventories Project: Methods
for Stream Habitat Surveys. Oregon Department of Fish and Wildlife, Corvallis, Oregon.
Peterson, N.P. and L.M. Reid. 1984. “Wall-base channels: their evolution, distribution and use
by juvenile coho salmon in the Clearwater River, Washington.” Pages 215–226 in J.M.
Walton and D.B. Houston, editors. Proceedings of the Olympic Wild Fish Conference:
Port Angeles.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 24 February 2013
Powers, P. D., and J. F. Orsborn. 1985. Analysis of barriers to upstream fish migration, an
investigation of the physical and biological conditions affecting fish passage success at
culverts and waterfalls. Washington State University, Department of Civil Engineering,
Albrook Hydraulics Lab, Pullman, WA.
Trihey, E. W. 1982. Preliminary assessment of access by spawning salmon to side slough habitat
above Talkeetna. Susitna Hydroelectric Project Doc. No. 134. 24 pp.
USFS (U.S. Department of Agriculture, Forest Service). 2001. FSH 2090.21 – Aquatic Habitat
Management Handbook Chapter 20 Fish and Aquatic Stream Habitat Survey. November
16, 2001. Juneau, Alaska.
Washington Department of Ecology. 2012. Channel Migration Assessment. Accessed online
December 2012.
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5. TABLES
Table 1. Fish passage barrier descriptions. The Barrier ID reflects the Susitna historic river mile
where the tributary enters the river and the letters denote multiple barriers within the same
tributary.
Barrier ID
Location
(tributary
RM)
Category
Barrier/Potenti
al Barrier
Present
Class Description
PB150.1-A 0.1 Permanent Barrier Compound
Permanent anadromous barrier
with falls > 10 ft. Cascades and
chutes upstream and
downstream
PB150.2-A 0.2 Permanent Barrier Complex Chute
Permanent anadromous barrier
due to low flow, high gradient
and complex chutes
PB151.0-A 0.1 Permanent Barrier Complex Chute
Permanent anadromous barrier
due to low flow, high gradient
and complex chutes
PB152.0-A 0.5 Permanent Barrier Compound
Permanent anadromous barrier
with falls > 10 ft, low flow, high
gradient, cascades, and complex
chutes
PB152.4-A 2.1 Permanent Potential Compound
Potential seasonal barrier due to
high gradient boulder cascades
falls 3-4 ft, chutes, and high
velocity turbulence
PB152.4-B 2.1 Permanent Barrier Multiple Falls
Permanent anadromous barriers
(2) with falls > 10 ft and shallow
plunge pool
PB152.4-C 2.1 Permanent Barrier Single Falls Permanent anadromous barrier
with waterfall much >10 ft
PB153.4-A 0.3 Permanent Barrier Single Falls Permanent anadromous barrier
with falls > 30 ft
PB154.5-A 0.1 Permanent Barrier Multiple Falls Permanent anadromous barrier
with high velocity falls > 10 ft
PB154.6-A 0.1 Permanent Barrier Complex Chute
Permanent anadromous barrier
with high velocity bedrock
chutes
PB155.3-A 0.1 Permanent Barrier Compound Permanent anadromous barrier
with falls > 10 ft
PB155.3-B 0.1 Permanent Barrier Single Falls Permanent anadromous barrier
with falls 12-15 ft
PB155.3-C 0.1 Permanent Potential Boulder
Cascade
Continuous boulder/cascade
complex with limited resting
areas
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Barrier ID
Location
(tributary
RM)
Category
Barrier/Potenti
al Barrier
Present
Class Description
PB157.0-A 1.3 Permanent Barrier Single Falls Permanent anadromous barrier
with falls > 10 ft
PB158.8-A 0.1 Permanent Barrier Compound Permanent anadromous barrier
with falls > 30 ft
PB161.5-A 1.4 Permanent Barrier Single Falls Permanent anadromous barrier
with falls estimated at 80- 100 ft
PB161.5-B 1.4 Permanent Barrier Single Falls Permanent anadromous barrier
with falls estimated at 40 ft
PB161.5-C 1.4 Permanent Potential Compound Chutes and falls with continuous
whitewater
PB165.0-A 0.1 Permanent Barrier Single Falls Permanent anadromous barrier
with falls > 10 ft
PB165.2-A 0.2 Permanent Barrier Single Falls Permanent anadromous barrier
with falls > 10- 12 ft
PB165.6-A 1.3 Permanent Potential Compound
Potential barrier due to steep
gradient boulder cascades and
falls to 6 ft with limited resting
places and plunge pools
PB168.7-A 0.4 Permanent Barrier
Boulder
Cascade
Complex Chute
Permanent anadromous barrier
with multiple boulder cascades
and complex chutes
PB171.0-A 1.4 Permanent Barrier Complex Chute
Permanent anadromous barriers
due to low flow, high gradient
and complex chutes
PB171.0-B 1.4 Permanent Barrier Complex Chute
Permanent anadromous barriers
due to low flow, high gradient
and complex chutes
PB171.0-C 1.4 Permanent Barrier Complex Chute
Permanent anadromous barriers
due to low flow, high gradient
and complex chutes
PB171.0-D 1.4 Permanent Barrier Complex Chute
Permanent anadromous barriers
due to low flow, high gradient
and complex chutes
PB171.3-A 0.1 Permanent Barrier Complex Chute Potential barrier due to complex
bedrock chutes
PB173.0-A 0.2 Permanent Barrier Multiple Falls
Permanent anadromous barrier
with multiple falls > 6 ft and
limited resting places or plunge
pools
PB179.1-A 2.8 Permanent Barrier Single Falls Permanent anadromous barrier
with falls > 15 ft
PB181.2-A 1.8 Permanent Barrier Single Falls Permanent anadromous barrier
with falls > 30 ft
PB181.8-A 3.8 Permanent Barrier Single Falls Permanent anadromous barrier
with falls > 60 ft
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Barrier ID
Location
(tributary
RM)
Category
Barrier/Potenti
al Barrier
Present
Class Description
PB186.6-A 0.6 Permanent Barrier Single Falls Permanent anadromous barrier
with falls > 50 ft
PB186.9-A 0.4 Permanent Potential Complex Chute
Potential barrier due to low
flow, high gradient cascades,
and bedrock chutes
PB194.9-A 1.3 Permanent Barrier
Multiple Falls
Boulder
Cascade
Steep gradient boulder cascades
and falls with limited resting
places and plunge pools.
Measured vertical distance 15 ft.
PB200.7-A 0.2 Permanent Barrier Single Falls
Permanent anadromous barriers
with single falls estimated at 10
-12 ft
PB200.7-B 0.2 Permanent Barrier Single Falls
Permanent anadromous barriers
with single falls estimated at 40-
50 ft
PB200.7-C 0.2 Permanent Barrier Single Falls
Permanent anadromous barriers
with single falls estimated at 15-
20 ft
PB200.7-D 0.2 Permanent Barrier Single Falls
Permanent anadromous barriers
with single falls estimated at 11-
12 ft
PB200.7-E 0.2 Permanent Barrier Single Falls
Permanent anadromous barriers
with single falls estimated at
20ft
PB201.8-A 0.4 Permanent Potential Compound
Potential barriers due to steep
gradient boulder cascades and
falls to 6 ft with limited resting
places and plunge pools.
PB201.8-B 0.6 Permanent Potential Compound
Potential barriers due to steep
gradient boulder cascades and
falls to 6 ft with limited resting
places and plunge pools
PB213.0-A 0.6 Permanent Potential Compound
Potential barrier due to steep
gradient boulder cascades and
falls to 6 ft with limited resting
places and plunge pools
PB226.8-A 0.7 Permanent Barrier Single Falls Permanent anadromous barrier
with falls > 15ft
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Table 2. Susitna River Mainstem and Mesohabitat Type Descriptions1
Classification
Level Type Description
Mainstem
Habitat Type
Main Channel
Channels of the river that convey streamflow throughout the year. Can include
single or multiple channels. In the Susitna River, they are visually recognizable
during summer months by turbid, glacial water and high velocities. In general,
they convey more than 10 percent (approximate) of the total flow passing a
given location. 2,3
Side Channel
Channels that contain streamflows during open water periods but may be
dewatered in a portion of the channel or entirely at low flows.1 These channels
carry mainstem water so also may be characterized by turbid, glacial water.
Velocities often appear lower than in mainstem sites. In general, they convey
less than 10 percent (approximate) of the total flow passing a given location. 1
Side channel habitat may exist in well-defined channels or in areas possessing
numerous islands and submerged gravel bars.
Tributary
Mouth
Clear water areas that exist where tributaries flow into Susitna River mainstem
or side channel habitats.1 The flow of this habitat type often manifests as a
clear water plume extending out into the turbid receiving water of the
mainstem Susitna River. Tributary mouth habitat also extends upstream into
the tributary to the upper extent of any backwater influence that might exist.
The surface area of tributary mouth habitat is affected both by tributary
discharge and mainstem stage. 3
Tributary
Those reaches of tributary streams upstream of the tributary mouth habitats.
Tributary habitat may contain distinct mainstem channel types, off-channel
waterbodies, and mesohabitat types.
Off-Channel
Aquatic habitats located beyond a river’s active channel, yet still within the
river’s active valley. Off-channel habitats lack an upstream surface water
connection to the main channel at intermediate or low flows, although
downstream surface water connections may exist. Off-channel habitats convey
water or contain water from small tributaries, upwelling groundwater, and/or
local surface runoff.
Off-Channel
Type
Side Slough
(Low flow
slough)
Overflow channels contained within the Susitna River floodplain that are
separated from the mainstem at the upstream end by exposed alluvial berm.1
These channels generally contain clear water from small tributaries, upwelling
groundwater, and local surface runoff. Side sloughs have non-vegetated bars at
their upstream ends that are overtopped during periods of moderate to high
mainstem discharge. The water surface elevation of the mainstem Susitna
River at the downstream end of a side slough generally causes a backwater
effect in the lower portion of the slough. Overtopping from mainstem flows
occurs multiple times for short durations June through August. 2 Except during
periods of overtopping, the temperature of side sloughs is independent of the
mainstem water temperature.
Upland Slough
(Slough)
Similar to side sloughs except they are separated from the mainstem channel or
a side channel by a well vegetated berm. Upland sloughs contain clear water
from small streams, upwelling, and/or local surface runoff. Upland sloughs are
rarely overtopped by mainstem discharge. 2,3
Backwater
Found along channel margins and created by mainstem flow eddies around
obstructions such as boulders, root wads, or in-channel wood. Part of active
channel at most flows; scoured at high flow. Substrate typically sand, gravel,
and cobble. Generally not as long as the full channel width. 4
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Classification
Level Type Description
Isolated Pond
A self-contained off-channel waterbody that lacks a surface water connection
to the river when the main channel flow is less than bankfull. Substrate is
highly variable.
Relic Channel An abandoned channel lacking active flow. 6
Mesohabitat
Type
Cascade
A fast water habitat with turbulent flow; many hydraulic jumps, strong chutes,
and eddies and between 30-80% white water. High gradient; usually greater
than 4% slope. Much of the exposed substrate composed of boulders organized
into clusters, partial bars, or step-pool sequences. 4
Pocketwater
A stream section intermediate in slope to the slopes observed for cascades and
riffles in the subject stream, but absent clear cross-channel steps characteristic
of a cascade, and the flow patterns are more complex and not cha racteristic of
riffles (where turbulence is visibly distributed more or less evenly across the
channel). There are multiple, prominent pockets of velocity refuges distributed
across and along the channel that are downstream of flow obstructions. The
obstructions are mostly small boulders that are of a size scaling with mid - to
high-flow depth. The unit should be at least 1 channel width long to be
classified separately, otherwise lump in with most similar adjacent mesohabitat
type.
Riffle
A fast water habitat with turbulent, shallow flow over submerged or partially
submerged gravel and cobble substrates. 4 Gradients are approximately 2 to less
than 4%.
Run
A fast water habitat with little surface turbulence. A run has generally uniform
depth that is greater than the maximum substrate size. 4 Gradients are
approximately 0 to less than 2%.
Pool A slow water habitat with a flat surface slope and low water velocity that is
deeper than the average channel depth. Substrate is highly variable. 4
Beaver
Complex
A complex waterbody created by beaver dams that includes one or more
ponded areas, connecting channels, and outlet channel to the mainstem, side or
a tributary channel. Substrate is generally fine grained sand, silt and organic
debris.
Pool Subtypes
Scour Pool
Formed by mid-channel scour or flow impinging against one stream bank or
partial obstruction (logs, root wad, or bedrock). Generally with a broad scour
hole. Includes corner pools in meandering lowland or valley bottom streams. 4
Backwater
Pool
Found along channel margins; created by eddies around obstructions such as
boulders, root wads, or woody debris. Part of active channel at most flows;
scoured at high flow. Substrate typically sand, gravel, and cobble. Generally
not as long as the full channel width. 4
Beaver Pond Water impounded by the creation of a beaver dam. Maybe within main, side,
or off-channel habitats. 4
Other Alcove
An off-channel habitat that is laterally displaced from the general bounds of
the active channel and formed during extreme flow events or by beaver
activity; not scoured during typical high flows. Substrate is typically sand and
organic matter. Generally not as long as the full channel width. 4
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Classification
Level Type Description
Percolation
Channel
A slough habitat type that is characterized by groundwater percolation from
the floodplain through gravel bars. Its upstream surface water connection to the
active river channel has been cut off due to an accumulation of sediment and
debris at the head of the formerly open channel, yet main river flows continue
to provide a groundwater source of flow to the percolation channel. At high or
overbank flows, an upstream surface water connection to the active river
channel may be present. 5
Isolated Pond
A self-contained off-channel waterbody that lacks a surface water connection
to the main channel when flow is less than bankfull. Substrate is highly
variable. An isolated pond may occur within the off-channel slough habitats or
elsewhere in the off-channel portion of the river valley. 3
Notes:
1 Table agreed upon by the ATWG for mesohabitat classifications
2 Source: Trihey 1982.
3 Source: Schmidt et al. 1984.
4 Source: Adapted from Moore et al. 2006.
5 Source: Adapted from Peterson and Reid 1984.
6 Source: Adapted from Washington Department of Ecology, Channel Migration Assessment.
Table 3. Substrate Classification
Substrate Type Size Range (mm)
Organic Organic
Sand/Silt < 2.0
Gravel 2.0-63.9
Small Cobble 64.0-127.9
Large Cobble 128.0-255.9
Small Boulder 256-512
Large/Med Boulder > 512
Bedrock Bedrock
Notes:
1 Appended from the USFS (2001) classification.
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Table 4. Riparian Vegetation Classification
Riparian Type Code
Conifer Forest - Closed Canopy CFC
Conifer Forest - Open Canopy CFO
Broad leaf Forest - Closed Canopy BFC
Broad leaf Forest - Open Canopy BFO
Nonforest Shrub - Willow Dominant NSW
Nonforest Shrub - Alder Dominant NSA
Nonforest Shrub – Other NSO
Nonforest Herbaceous – Estuarine NHE
Nonforest Herbaceous – Bog NHB
Nonforest Herbaceous – Fen NHF
Nonforest Herbaceous – Other NHO
Notes:
1 From the USFS (2001) classifications.
Table 5. Stream Cover Types
Cover Type Codes
Tree Bole TB
Rootwad RW
Slash SL
Debris Jam DJ
Bedrock BR
Large/Medium Boulder LMB
Small Boulder SB
Large Cobble LC
Undercut Bank UCB
Depth De
Bridge/culvert BC
Weir W
Log Structures HL
Boulder Structures HB
Overhanging Vegetation OV
Aquatic Vegetation AV
Other Human HU
Notes:
1 From the USFS (2001) classification
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Table 6. Jay Creek Reach 1 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle (pocketwater)
Riffle 243 54.9% 6 40.0% 10.0 12.0 2.0 0.4 18 2 1 3 13 18
Run (pocketwater)
Run 200 45.1% 9 60.0% 8.0 11.0 3.0 0.7 0 2 10 8 6 17
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 443 100.0% 15 100.0% 9 12 2.5 0.5 0.0 0.0 9 2 5 6 10 18
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Table 7. Jay Creek Reach 1 – Mainstem Riparian Vegetation
Riparian Vegetation Number Length (m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy 1 NRD
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 13 422 95.3
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None 1 21 4.7
TOTAL 15 443 100.0
Table 8. Jay Creek Reach 1 - Mainstem Substrate
Unit Type Bedrock
%
Boulder
%
Cobble
%
Gravel
%
Sand/Silt
%
Organic
%
Cascade Riffle 32 50 18 Riffle
(pocketwater)
Run 28 46 23 3 Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation
Channel
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Table 9. Jay Creek Reach 1 – Side Channel Summary Statistics (Mapped Habitat Units) Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade 9 2.0% 1 10.0% 5.0 11.0 5.0 0.3 0 0 1 0 0 0
Riffle (pocketwater)
Riffle 29 6.5% 3 30.0% 4.0 6.0 3.0 0.2 0 0 3 0 0 28
Run (pocketwater)
Run 30 6.8% 3 30.0% 3.0 7.0 2.0 0.4 0 0 5 2 0 32
Scour Pool 17 3.8% 1 10.0% 5.0 8.0 0.0 0.3 0.6 0 0 24 0 80 30
Backwater Pool 5 1.1% 1 10.0% 3.0 9.0 0.0 0.7 0 0 2 0 70 50
Slough 10 2.3% 1 10.0% 1.0 5.0 0.0 0.4 100 0 25 0 0 100
Beaver Complex
Percolation Channel
TOTAL 100 100.0% 10 100.0% 4 7 1.7 0.2 0.1 0.1 17 0 9 1 17 35
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Table 10. Jay Creek Reach 1 – Side Channel Riparian Vegetation
Riparian Vegetation Number Length (m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy 2 19 19%
Nonforest Shrub - Willow Dominant 7 76 76%
Nonforest Shrub - Alder Dominant 1 5 5%
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 10 100 100%
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Table 11. Jay Creek Reach 1 – Side Channel Substrate
Unit Type Bedrock
%
Boulder
%
Cobble
%
Gravel
%
Sand/Silt
%
Organic
%
Cascade 40 60
Riffle 10 30 47 13 Riffle (pocketwater)
Run 20 53 20 7 Run (pocketwater) 30 47 13
Scour Pool 20 10 70
Backwater Pool 40 10 50
Slough 40 60
Beaver Complex
Percolation Channel
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Table 12. Jay Creek - Reach 2 - Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 126 16.2% 4 44.4% 11.0 13.0 2.0 0.5 3 13 1 0 2 NRD
Riffle (pocketwater)
Run 650 83.8% 5 55.6% 11.0 15.0 2.0 0.6 15 14 13 2 2 NRD
Run (pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 776 100.0% 9 100.0% 11 15 2 1 0 0 9 14 7 1 2 NRD
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Table 13. Jay Creek Reach 2 - Mainstem Riparian Vegetation
Mainstem Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy 1 52 6.7
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 5 391 50.4
Nonforest Shrub - Alder Dominant 3 333 42.9
Nonforest Shrub – Other
Nonforest Herbaceous – Estuarine
Nonforest Herbaceous – Bog
Nonforest Herbaceous – Fen
Nonforest Herbaceous – Other
TOTAL 9 776 100
Table 14. Jay Creek Reach 2 – Mainstem Substrate
Unit Type Bedrock
%
Boulder
%
Cobble
%
Gravel
%
Sand/Silt
%
Organic
%
Cascade Riffle 0 35 33 30 3 0
Riffle (pocketwater) Run 0 46 26 26 2 Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
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Table 15. Jay Creek Reach 6 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 19 3.2% 1 20.0% 10.0 11.0 3.5 0.4 0 0 2 0 0 NRD
Riffle (pocketwater)
Run 549 93.2% 3 60.0% 8.0 12.0 3.0 0.7 10 17 20 20 3 NRD
Run (pocketwater)
Scour Pool 21 3.6% 1 20.0% 7.0 13.0 0.0 0.5 1.3 0 20 3 10 0 NRD
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 589 100.0% 5 100.0% 8 12 2 1 0 0 3 12 8 10 1 -
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Table 16. Jay Creek Reach 6 – Mainstem Riparian Vegetation
Mainstem Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy 1 21 3.6
Conifer Forest - Open Canopy 1 40 6.8
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 3 528 89.6
Nonforest Shrub - Alder Dominant
Nonforest Shrub – Other
Nonforest Herbaceous – Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous – Other
None
TOTAL 5 589 100.0
Table 17. Jay Creek Reach 6 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade
Riffle 0 20 40 40 0 0
Riffle (pocketwater)
Run 0 20 43 33 3 0
Run (pocketwater)
Scour Pool 0 0 40 40 20 0
Backwater Pool
Slough
Beaver Complex
Percolation Channel
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Table 18. Jay Creek Reach 6 - Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle (pocketwater)
Riffle 16 16.3% 1 20% 1.8 2.0 2.0 .2 0 0 0 0 0 NRD
Run (pocketwater)
Run 64 65.3% 2 40% 1.0 1.1 2.0 0.1 0 0 5 0 0 NRD
Scour Pool 6.0 6.1% 1 20% 2.0 2.2 2.0 0.1 0.5 0 0 0 0 30 NRD
Backwater Pool 12 12.2% 1 20% 2.5 2.7 0 0.6 0 0 0 0 0 NRD
Slough
Beaver Complex
Percolation Channel
TOTAL 98 100.0% 5 100.0% 1 2 2 0 0 0 0 0 1 0 8 NRD
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Table 19. Jay Creek Reach 6 – Side Channel Riparian Vegetation
Side Channel Riparian Vegetation Number Length (m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 5 98 100.0
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 5 98 100.0
Table 20. Jay Creek Reach 6 – Side Channel Substrate
Unit Type
Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 0 70 30 0 0
Riffle (pocketwater) Run 0 10 25 20 25 20
Run (pocketwater) Scour Pool 0 0 20 20 30 30
Backwater Pool 0 10 40 40 10 0
Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 43 February 2013
Table 21. Kosina Creek Reach 1 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle (pocketwater) 779 69.8% 6 54.5% 32.0 36.0 2.0 1.0 0 0 0 0 0 NRD
Riffle
Run (pocketwater) 337 30.2% 5 45.5% 24.0 30.4 2.0 1.7 0 0 0 0 0 NRD
Run
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 1116 100.0% 11 100.0% 30 34 2 1 0 0 0 0 0 0 0 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 44 February 2013
Table 22. Kosina Reach 1 – Mainstem Riparian Vegetation
Mainstem Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy Conifer Forest - Open Canopy Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy 1 60 5.4
Nonforest Shrub - Willow Dominant 5 462 41.4
Nonforest Shrub - Alder Dominant 5 594 53.2
Nonforest Shrub - Other Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other None TOTAL 11 1116 100.0
Table 23. Kosina Reach 1– Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade
Riffle 0 52 33 15 0 0
Riffle (pocketwater)
Run 4 60 30 6 0 0
Run (pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 45 February 2013
Table 24. Kosina Creek Reach 1 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 215 21.6% 5 21.7% 11.4 13.8 2.0 0.4 0 0 1 0 4 NRD
Riffle(pocketwater) 295 29.6% 5 21.7% 19.6 22.0 2.0 0.5 0 0 1 0 0 NRD
Run 285 28.6% 8 34.8% 13.6 16.3 2.0 0.6 3 0 1 1 1 NRD
Run(pocketwater) 68 6.8% 2 8.7% 15.5 17.5 2.0 0.7 0 0 2 0 0 NRD
Scour Pool 37 3.7% 2 8.7% 11.5 16.0 2.0 0.3 0.7 0 0 1 0 0 NRD
Backwater Pool
Slough
Beaver Complex
Percolation Channel 96 9.6% 1 4.3% 2.0 2.5 2.0 0.2 0 0 5 0 0 NRD
TOTAL 996 100.0% 23 100.0% 14 16 2 0 0 0 0 0 2 0 1 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 46 February 2013
Table 25. Kosina Reach 1 – Side Channel Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy 4 106 10.6
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy 7 378 37
Nonforest Shrub - Willow Dominant 6 267 26.8
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other 3 247 24.7
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 20 998 100.0
Table 26. Kosina Creek Reach 1 – Side Channel Substrate
Unit Type
Bedrock
%
Boulder
%
Cobble
%
Gravel
%
Sand/Silt
%
Organic
%
Cascade Riffle 0 36 40 24 0 0
Riffle (pocketwater) 0 44 44 12 0 0
Run 0 43 38 19 0 0
Run (pocketwater) 0 45 40 15 0 0
Scour Pool 0 45 30 20 5 0
Backwater Pool Slough Beaver Complex Percolation Channel 0 40 20 20 10 10
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 47 February 2013
Table 27. Kosina Creek Reach 2 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 383 66.3% 2 33.3% 31.0 32.0 2.0 1.1 0 0 1 0 0 NRD
Riffle(pocketwater)
Run 169 29.2% 3 50.0% 26.0 29.0 2.0 1.9 0 0 1 0 0 NRD
Run(pocketwater)
Scour Pool 26 4.5% 1 16.7% 11.0 16.0 2.0 NRD 2.0 0 0 1 0 0 NRD
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 578 100.0% 6 100.0% 29 30 2 1 0 0 0 0 1 0 0 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 48 February 2013
Table 28. Kosina Creek Reach 2 – Mainstem Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 5 548 94.8
Nonforest Shrub - Alder Dominant 1 30 5.2
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 6 578 100.0
Table 29. Kosina Creek Reach 2 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 60 30 10 0 0
Riffle (pocketwater) Run 3 57 33 7 0 0
Run (pocketwater) Scour Pool 0 70 30 0 0 0
Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 49 February 2013
Table 30. Kosina Reach 2 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle
Riffle(pocketwater) 55 100.0% 1 100.0% 11.0 12.0 2.0 0.7 0 0 0 0 0 NRD
Run
Run(pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 55 100.0% 1 100.0% 11 12 2 1 0 0 0 0 0 0 0 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 50 February 2013
Table 31. Kosina Reach 2 – Side Channel Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy Conifer Forest - Open Canopy Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy Nonforest Shrub - Willow Dominant Nonforest Shrub - Alder Dominant 1 55 100.0
Nonforest Shrub - Other Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other None TOTAL 1 55 100.0
Table 32. Kosina Reach 2 – Side Channel Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle Riffle (pocketwater) 0 40 30 30 0 0
Run Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 51 February 2013
Table 33. Kosina Creek Reach 3 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 464 85.0% 2 66.7% 35.5 37.5 2.0 1.5 0 0 3 0 0 NRD
Riffle(pocketwater)
Run 82 15.0% 1 33.3% 19.0 26.0 2.0 1.5 0 0 1 0 0 NRD
Run(pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 546 100.0% 3 100.0% 33 36 2 2 0 0 0 0 2 0 0 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 52 February 2013
Table 34. Kosina Creek Reach 3 – Mainstem Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy 1 262 48.0
Nonforest Shrub - Willow Dominant 2 284 52.0
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 3 546 100.0
Table 35. Kosina Creek Reach 3 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 60 30 10 0 0
Riffle (pocketwater) Run 0 60 30 10 0 0
Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 53 February 2013
Table 36. Kosina Creek Reach 3 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 137 38.0% 2 25.0% 12.5 13.5 2.0 0.7 0 0 1 10 0 NRD
Riffle(pocketwater) 99 27.4% 1 12.5% 13.0 13.0 2.0 0.6 0 0 3 20 0 NRD
Run 68 18.8% 3 37.5% 10.0 12.3 2.0 0.8 0 0 1 3 23 NRD
Run(pocketwater) 57 15.8% 2 25.0% 9 12 2 0.9 0 0 3 0 30 NRD
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 361 100.0% 8 100.0% 12 13 2 1 0 0 0 0 2 8 13 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 54 February 2013
Table 37. Kosina Creek Reach 3 – Side Channel Riparian Vegetation
Riparian Vegetation Number Length (m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy 2 47 13.0
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 3 217 60.1
Nonforest Shrub - Alder Dominant 3 97 26.9
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 6 361 100.0
Table 38. Kosina Reach 3 – Side Channel Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 60 30 10 Riffle (pocketwater) 60 30 10 Run 50 23 17 10 Run (pocketwater) 50 35 15 Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 55 February 2013
Table 39. Kosina Creek Reach 4 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade 81 8.9% 1 12.5
%
34.
0
56.
0 9.0 0.4 NR
D
NR
D
0 0.0 0.0 10
Riffle 32
1
35.2
% 2 25.0
%
27.
0
34.
5 2.0 0.5 8 5 0 0 3 23
Riffle(pocketw
ater)
30
7
33.7
% 3 37.5
%
44.
7
60.
7 2.0 0.5 1.7 1.7 0 0.0 0.0 28.
3
Run 12
1
13.3
% 1 12.5
%
37.
0
39.
0 2.0 NR
D 10 NR
D
0 NR
D
0 40
Run(pocketwat
er) 81 8.9% 1 12.5
%
34.
0
51.
0 2.0 NR
D 5 5 0 10 10 40
Scour Pool
Backwater
Pool
Slough
Beaver
Complex
Percolation
Channel
TOTAL 91
1
100.0
% 8
100.0
% 36 47 3 0 0 0
6 4 0 3 3 28
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 56 February 2013
Table 40. Kosina Creek Reach 4 – Mainstem Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 8 911 100.0
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 8 911 100
Table 41. Kosina Creek Reach 4 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade 0 50 30 20 0 0
Riffle 0 35 30 30 5 0
Riffle (pocketwater) 0 37 37 23 3 0
Run 0 40 30 30 0 0
Run (pocketwater) 0 50 30 20 0 0
Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 57 February 2013
Table 42. Kosina Reach 4 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle
Riffle(pocketwa
ter)
Run
Run(pocketwate
r)
Scour Pool
Backwater Pool
Slough
Beaver
Complex
Percolation
Channel 38 100.0
% 1 100.0
% 1.4 4.0 2.0 0.1 0 0 0 0 0 5
TOTAL 38 100.0
% 1 100.0
% 1 4 2 0 0 0 0 0 0 0 0 5
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 58 February 2013
Table 43. Kosina Creek Reach 4 – Side Channel Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 1 38 100
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 1 38 100
Table 44. Kosina Creek Reach 4 – Side Channel Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle Riffle (pocketwater) Run Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel 0 10 20 40 30 0
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 59 February 2013
Table 45. Kosina Creek Reach 5 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 16
9
33.9
% 1 25.0
%
33.
0
44.
0 2.0 NR
D 10 NR
D
0 NR
D
0 40
Riffle
(pocketwater) 89 17.9
% 1 25.0
%
29.
0
37.
0 2.0 NR
D 0.0 NR
D
0 NR
D
0.0 30
Run 24
0
48.2
% 2 50.0
%
38.
5
44.
0 2.0 NR
D 5 NR
D
0 NR
D
0 35
Run
(pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver
Complex
Percolation
Channel
TOTAL 49
8
100.0
% 4
100.0
% 35 43 2 - - -
5 - 0 - 0 35
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 60 February 2013
Table 46. Kosina Creek Reach 5 – Mainstem Riparian Vegetation
Riparian Vegetation Number
Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 4 498 100.0%
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 4 498 100
Table 47. Kosina Creek Reach 5 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 10 30 30 20 10 0
Riffle (pocketwater) 0 30 20 20 30 0
Run 10 40 20 15 15 0
Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 61 February 2013
Table 48. Kosina Creek Reach 5 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle
Riffle(pocketwa
ter)
Run 28 100.0
% 1 100.0
% 2.0 4.0 2.0 NR
D 0 0 0 0 0 70
Run
(pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver
Complex
Percolation
Channel
TOTAL 28 100.0
% 1 100.0
% 2 4 2 0 0 0 0 0 70
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 62 February 2013
Table 49. Kosina Creek Reach 5 – Side Channel Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant
Nonforest Shrub - Alder Dominant 1 28 100
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL
Table 50. Kosina Creek Reach 5 – Side Channel Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade
Riffle
Riffle (pocketwater)
Run 30 30 10 10 20 0
Run (pocketwater)
Scour Pool Backwater Pool
Slough
Beaver Complex
Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 63 February 2013
Table 51. Kosina Creek Reach 6 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 19
2
28.5
% 1 33.3
%
55.
0
66.
0 2.0 NR
D 0 NR
D
0 NR
D
0 20
Riffle(pocketw
ater)
Run 48
1
71.5
% 2 66.7
%
55.
0
69.
0 2.0 NR
D 28 NR
D
0 NR
D
0 40
Run(pocketwat
er)
Scour Pool
Backwater Pool
Slough
Beaver
Complex
Percolation
Channel
TOTAL 67
3
100.0
% 3
100.0
% 55 68 2 - -! -
14 - 0 - 0 30
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 64 February 2013
Table 52. Kosina Creek Reach 6 – Mainstem Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 3 673 100.0%
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 3 673 100
Table 53. Kosina Creek Reach 6 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 30 20 30 20 0
Riffle (pocketwater) Run 0 40 30 20 10 0
Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 65 February 2013
Table 54. Kosina Creek Reach 7 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle
(pocketwater)
NR
D 1 12.5% NR
D
NR
D 2.0 0.5 0 NR
D
0 NR
D
5 0
Riffle
Run
(pocketwater)
NR
D 7 87.5% 59.
5
82.
5 1.0 0.7 0 2 0 0 20 10
Run
Scour Pool
Backwater Pool
Slough
Beaver
Complex
Percolation
Channel
TOTAL 8
100.0
% - - 2 - - -
0 2 0 0 13 5
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 66 February 2013
Table 55. Kosina Creek Reach 7 – Mainstem Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy Conifer Forest - Open Canopy Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy Nonforest Shrub - Willow Dominant 5 NRD Nonforest Shrub - Alder Dominant Nonforest Shrub - Other 1 NRD Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other 2 NRD None TOTAL 8 - -
Table 56. Kosina Creek Reach 7 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 40 30 20 10 0
Riffle (pocketwater) Run 0 33 29 24 14 0
Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 67 February 2013
Table 57. Kosina Reach 7 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle
Riffle(pocketwa
ter)
Run NR
D 8 66.7% 12.
5 52.0 2.0 0.3 5 9 0 1 1 6
Run(pocketwate
r)
Scour Pool NR
D 2 16.7% 3.0 NR
D
NR
D 0.4 0.8 0 30 0 15 0 10
Backwater Pool
Slough NR
D 1 8.3% 1.3 NR
D
NR
D 0.3 0 0 0 0 0 20
Beaver
Complex
Percolation
Channel
NR
D 1 8.3% 1.5 NR
D
NR
D 0.3 15 15 0 10 10 20
TOTAL 12 100.0
%
18.
3 52.0 2 0.9 0.4 0.8 5 14 0 7 3 14
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 68 February 2013
Table 58. Kosina Reach 7 – Side Channel Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy Conifer Forest - Open Canopy Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy Nonforest Shrub - Willow Dominant 7 NRD Nonforest Shrub - Alder Dominant 1 NRD Nonforest Shrub - Other 1 NRD Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other 3 NRD None Conifer Forest - Closed Canopy 12 NRD
Table 59. Kosina Reach 7 – Side Channel Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle Riffle (pocketwater) Run 0 18 30 30 23 0
Run (pocketwater) Scour Pool 0 0 0 50 50 0
Backwater Pool Slough 0 0 10 10 70 10
Beaver Complex Percolation Channel 0 0 0 40 20 40
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 69 February 2013
Table 60. Kosina Creek Reach 8 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 159 16.2% 1 14.3% 112.0 113.0 3.5 0.7 0 0 0 20 10 NRD
Riffle(pocketwater)
Run 825 83.8% 6 85.7% 94.7 96.2 2.0 1.3 0 0 0 20 13 NRD
Run(pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 984 100.0% 7 100.0% 97 99 3 1 - - 0 0 0 20 12 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 70 February 2013
Table 61. Kosina Creek Reach 8 – Mainstem Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 7 984 100.0
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 7 984 100
Table 62. Kosina Creek Reach 8 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 60 20 10 10 0
Riffle (pocketwater) Run 50 30 10 10 0 0
Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 71 February 2013
Table 63. Kosina Creek Reach 8 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 44 31.7% 1 25.0% 6.0 7.0 2.0 0.4 0 0 0 10 0 NRD
Riffle(pocketwater)
Run 95 68.3% 3 75.0% 10.7 11.3 2.0 0.5 0 0 0 3 10 NRD
Run(pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 139 100.0% 4 100.0% 9 10 2 0 - - 0 0 0 7 5 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 72 February 2013
Table 64. Kosina Creek Reach 8 – Side Channel Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy Conifer Forest - Open Canopy Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy Nonforest Shrub - Willow Dominant 4 139 100
Nonforest Shrub - Alder Dominant Nonforest Shrub - Other Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other None TOTAL 4 139 100
Table 65. Kosina Creek Reach 8 – Side Channel Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade
Riffle 0 50 30 10 10 0
Riffle (pocketwater)
Run 0 43 20 13 23 0
Run (pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 73 February 2013
Table 66. Watana Creek Reach 1 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle (pocketwater) 551 60.6% 5 50.0% 22.0 24.0 2.0 0.5 38 6 12 0 16 NRD
Riffle
Run (pocketwater) 358 39.4% 5 50.0% 13.0 18.0 NRD 1.0 4 17 7 0 6 NRD
Run
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 909 100.0% 10 100.0% 18 22 2 1 0 0 21 12 10 0 11 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 74 February 2013
Table 67. Watana Creek Reach 1 – Mainstem Riparian Vegetation
Mainstem Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy 1 214 23.5
Conifer Forest - Open Canopy Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy Nonforest Shrub - Willow Dominant 7 466 51.3
Nonforest Shrub - Alder Dominant 2 229 25.2
Nonforest Shrub - Other Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other None TOTAL 10 909 100.0
Table 68. Watana Creek Reach 1 – Mainstem Substrate
Unit Type
Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 0 72 28 0 0
Riffle (pocketwater) Run 2 12 68 18 0 0
Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 75 February 2013
Table 69. Watana Creek Reach 3 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle
Riffle(pocketwater)
Run 62 100 1 100 21 23 2.0 0.6 - -
Run(pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 62 100 1 100 21 23 2.0 1 - - 0 0 0 0 0 -
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 76 February 2013
Table 70. Watana Creek Reach 3 – Mainstem Riparian Vegetation
Mainstem Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 1 62 100.0%
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 1 62 100
Table 71. Watana Creek Reach 3 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade
Riffle
Riffle (pocketwater)
Run 0 0 40 40 20 0
Run (pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 77 February 2013
Table 72. Watana Creek Reach 3 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle
Riffle (pocketwater)
Run
Run (pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel 36 100.0% 1 100.0% 1.2 1.4 2.0 0.1 0 0 0 0 0 40
TOTAL 36 100.0% 1 100.0% 1 1 2 0 - - 0 0 0 0 0 40
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 78 February 2013
Table 73. Watana Creek Reach 3 – Side Channel Riparian Vegetation
Side Channel Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy
Broad leaf Forest - Closed Canopy
Broad leaf Forest - Open Canopy
Nonforest Shrub - Willow Dominant 1 36 100
Nonforest Shrub - Alder Dominant
Nonforest Shrub - Other
Nonforest Herbaceous - Estuarine
Nonforest Herbaceous - Bog
Nonforest Herbaceous - Fen
Nonforest Herbaceous - Other
None
TOTAL 1 36 100
Table 74. Watana Creek Reach 3 – Side Channel Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade
Riffle
Riffle (pocketwater)
Run
Run (pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel 0 0 0 40 60 0
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 79 February 2013
Table 75. Watana Creek Reach 4- Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 608 79.1% 4 66.7% 17.0 19.0 2.0 0.5 1 1 4 0 0 20
Riffle (pocketwater)
Run 161 20.9% 2 33.3% 17.0 19.0 2.0 0.8 3 5 1 3 0 10
Run (pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 769 100.0% 6 100.0% 17 19 2 1 - - 2 3 3 2 0 15
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 80 February 2013
Table 76. Watana Creek Reach 4 – Mainstem Riparian Vegetation
Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy Conifer Forest - Open Canopy Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy Nonforest Shrub - Willow Dominant 5 703 91.4
Nonforest Shrub - Alder Dominant 1 66 8.6
Nonforest Shrub - Other Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other None TOTAL 6 769 100
Table 77. Watana Creek Reach 4 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 13 45 33 10 0
Riffle (pocketwater) Run 0 15 35 35 15 0
Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 81 February 2013
Table 78. Watana Creek Reach 4 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle (pocketwater) 94 27.8% 3 25.0% 5.0 6.0 2.0 1.0 0 0 2 0 2 5
Riffle 49 14.5% 1 8.3% 4.0 5.0 2.0 0.2 0.0 0.0 0 0.0 0.0 NRD
Run (pocketwater) 20 5.9% 1 8.3% 3.0 5.0 2.0 0.3 20 0 1 0 20 NRD
Run 30 8.9% 1 8.3% 5.0 5.0 2.0 0.3 0 0 3 0 0 NRD
Scour Pool 52 15.4% 3 25.0% 5.0 6.0 2.0 0.2 0.6 16 0 5 0 0 NRD
Backwater Pool 36 10.7% 1 8.3% 6.0 9.0 2.0 0.7 0 20 2 0 0 NRD
Slough 10 3.0% 1 8.3% 2.0 2.0 2.0 0.2 0.0 0 7 0 10 NRD
Beaver Complex 47 13.9% 1 8.3% 14.0 16.0 2.0
0.7 0 5 10 0 0 NRD
Percolation Channel
TOTAL 338 100.0% 12 100.0% 6 7 2 0 0 0 5 3 4 0 4 5
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 82 February 2013
Table 79. Watana Creek Reach 4 – Side Channel Riparian Vegetation
Side Channel Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy 1 20 5.9
Conifer Forest - Open Canopy 1 47 13.9
Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy 1 11 3.3
Nonforest Shrub - Willow Dominant 4 131 38.8
Nonforest Shrub - Alder Dominant 5 129 38.2
Nonforest Shrub - Other Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other None TOTAL 12 338 100.0
Table 80. Watana Creek Reach 4 – Side Channel Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 3 37 47 13 0
Riffle (pocketwater) 0 20 70 10 0 0
Run 0 0 10 80 10 0
Run (pocketwater) 0 40 50 10 0 0
Scour Pool 0 13 40 30 17 0
Backwater Pool 0 0 40 30 30 0
Slough 0 0 0 0 50 50
Beaver Complex 0 0 0 0 50 50
Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 83 February 2013
Table 81. Watana Creek Reach 6 – Mainstem Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade
Riffle 460 62.8% 3 60.0% 8.7 12.0 2.0 0.3 0 0 2 0 0 5
Riffle (pocketwater)
Run 273 37.2% 2 40.0% 11.0 16.0 2.0 0.5 3 0 7 0 0 0
Run (pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel
TOTAL 733 100.0% 5 100.0% 10 13 2 0 - - 1 0 4 0 0 3
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 84 February 2013
Table 82. Watana Creek Reach 6 – Mainstem Riparian Vegetation
Mainstem Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy
Conifer Forest - Open Canopy Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy Nonforest Shrub - Willow Dominant 5 733 100.0
Nonforest Shrub - Alder Dominant Nonforest Shrub - Other Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other None TOTAL 5 733 100
Table 83. Watana Creek Reach 6 – Mainstem Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 13 37 47 3 0
Riffle (pocketwater) Run 0 15 40 45 0 0
Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 85 February 2013
Table 84. Watana Creek Reach 6 – Side Channel Summary Statistics (Mapped Habitat Units)
Unit Type Total Length (m) Length Rel Frequency Number of Units Number of Units (frequency) Average Wetted Width (m) Average Bankfull Width (m) Average Stream Gradient (%) Average Maximum Depth (m) Average Pool Crest Depth (m) Average maximum pool depth (m) Average Left Bank Erosion (%) Average Right Bank Erosion (%) Average LWD (pieces/unit) Average Right Undercut Bank (%) Average Left Undercut Bank (%) Average Cover (%) Cascade 82 40.7 2 50 1.4 6.0 2.0 0.1 0.0 0.0 0 0.0 0.0 20
Riffle
Riffle (pocketwater)
Run
Run (pocketwater)
Scour Pool
Backwater Pool
Slough
Beaver Complex
Percolation Channel 128 59.3% 2 50.0% 1.3 2.8 2.0 0.3 0 0 3 0 0 75
TOTAL 216 100.0% 4 100.0% 1 4 2 0 - - 0 0 1 0 0 48
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 86 February 2013
Table 85. Watana Creek Reach 6 – Side Channel Riparian Vegetation
Side Channel Riparian Vegetation Number Length
(m)
Relative
Frequency
(%)
Conifer Forest - Closed Canopy Conifer Forest - Open Canopy Broad leaf Forest - Closed Canopy Broad leaf Forest - Open Canopy Nonforest Shrub - Willow Dominant 4 88 100
Nonforest Shrub - Alder Dominant Nonforest Shrub - Other Nonforest Herbaceous - Estuarine Nonforest Herbaceous - Bog Nonforest Herbaceous - Fen Nonforest Herbaceous - Other None Total 4 88 100
Table 86. Watana Creek Reach 6 – Side Channel Substrate
Unit Type Bedrock
(%)
Boulder
(%)
Cobble
(%)
Gravel
(%)
Sand/Silt
(%)
Organic
(%)
Cascade Riffle 0 0 30 45 25 0
Riffle (pocketwater) Run Run (pocketwater) Scour Pool Backwater Pool Slough Beaver Complex Percolation Channel 0 5 20 30 30 15
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 87 February 2013
Table 87. Mesohabitat Unit Descriptions for 2013
Channel Type
(# of channels)
Hydraulic
Type
Mesohabitat
Type Definition
Single (1)
Split (2)
Channel
Complex (3 or
> channels)
Fast Water
Falls
Steep near vertical drop in water surface elevation greater
than approximately 5 ft over a permanent feature,
generally bedrock.
Cascade
A fast water habitat with turbulent flow; many hydraulic
jumps, strong chutes, and eddies and between 30-80%
white water. High gradient; usually greater than 4% slope.
Much of the exposed substrate composed of boulders
organized into clusters, partial bars, or step-pool
sequences. 1
Chute
An area where most of the flow is constricted to a channel
much narrower than the average channel width. Laterally
concentrated flow is generally created by a channel
impingement or a laterally asymmetric bathymetric
profile. Flow is fast and turbulent.
Rapid
Swift, turbulent flow including small chutes and some
hydraulic jumps swirling around boulders. Exposed
substrate composed of individual boulders, boulder
clusters, and partial bars. Lower gradient and less dense
concentration of boulders and white water than Cascade.
Moderate gradient; usually 2.0-4.0% slope, occasionally
7.0-8.0%. 1
Boulder Riffle
Same flow and gradient as Riffle but with numerous
boulders that can create sub-unit sized pools or pocket
water created by scour.
Riffle
A fast water habitat with turbulent, shallow flow over
submerged or partially submerged gravel and cobble
substrates. Generally broad, uniform cross section.1 Low
gradient; usually 0.5-2.0% slope, rarely up to 6%.
Run/Glide
A habitat area with minimal surface turbulence with
generally uniform depth that is greater than the maximum
substrate size.1 Velocities are on border of fast and slow
water. Gradients are approximately 0 to less than 2%.
Generally deeper than riffles with few major flow
obstructions and low habitat complexity.1
Slow
Water
Pool
A slow water habitat with a flat surface slope and low
water velocity that is deeper than the average channel
depth. Substrate is highly variable. 1
Pool subtypes
Straight Scour Pool: Formed by mid-channel scour.
Generally with a broad scour hole and symmetrical cross
section.1
Plunge Pool: Formed by scour below a complete or nearly
complete channel obstruction (logs, boulders, or bedrock).
Pool must be Substrate is highly variable. Frequently, but
not always, shorter than the active channel width.1
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 88 February 2013
Channel Type
(# of channels)
Hydraulic
Type
Mesohabitat
Type Definition
Lateral Scour Pool: Formed by flow impinging against
one stream bank or partial obstruction (logs, root wad, or
bedrock). Asymmetrical cross section. Includes corner
pools in meandering lowland or valley bottom streams.1
Backwater Pool: Found along channel margins; created
by eddies around obstructions such as boulders, root wads,
or woody debris. Part of active channel at most flows;
scoured at high flow. Substrate typically sand, gravel, and
cobble. Generally not as long as the full channel width. 1
Beaver Pond Water impounded by the creation of a beaver dam. Maybe
within main, side, or off-channel habitats. 1
Alcove
An off-channel habitat that is laterally displaced from the
general bounds of the active channel and formed during
extreme flow events or by beaver activity; not scoured
during typical high flows. Substrate is typically sand and
organic matter. Generally not as long as the full channel
width. An alcove is differentiated from a backwater being
more protected and not scoured at high flows wherea s a
backwater is part of the active channel and is scoured at
high flows 1
Off-
channel
Percolation
channel
A slough characterized by groundwater percolation
through the floodplain that comes from mainstem stream
channel. Upstream surface connection to active channel
cut off due to accumulation of sediment/debris at the
upstream end. Upstream surface water connection to the
active channel present only during high flows.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 89 February 2013
Table 88. Upper River tributaries and mainstem Susitna River sections aerial videotaped in 2012
Name Stream Section Confluence Date
Videotaped
Time
Start
Time
End
Rivermile
Start
Rivermile
End
Oshetna River
RM 0.0 to RM
15.6
Upper River Left Bank at RM
233.5 9/8/2012
1:40
PM
2:24
PM 0.0 15.6
Black River RM 0.0 to RM 3.4
Oshetna River Left Bank at
RM 12.7 9/8/2012
3:08
PM
3:19
PM 0.0 3.4
Goose Creek RM 0.0 to RM 7.8
Upper River Left Bank at RM
231.0 9/8/2012
3:26
PM
3:52
PM 0.0 7.8
Jay Creek
RM 0.0 to RM
10.4
Upper River Right Bank at
RM 208.6 9/9/2012
12:00
PM
12:40
PM 0.0 10.4
Jay Creek
Tributary RM 0.0 to RM 1.9
Jay Creek Right Bank at RM
8.1 9/9/2012
12:42
PM
12:51
PM 0.0 1.9
Kosina Creek
RM 22.1 to RM
0.0
Upper River Left Bank at RM
206.8 9/9/2012
4:39
PM
5:45
PM 22.1 0.0
Watana Creek
RM 0.0 to RM
18.4
Upper River Right Bank at
RM 194.1 9/9/2012
1:50
PM
2:50
PM 0.0 18.4
Watana Creek
Tributary RM 0.0 to RM 3.0
Watana Creek Right Bank at
RM 8.7 9/9/2012
2:55
PM
3:05
PM 0.0 3.8
Deadman Creek
RM 0.0 to RM
21.0
Upper River Right Bank at
RM 186.6 9/10/2012
3:09
PM
3:53
PM 0.0 21.0
Tsusena Creek RM 0.0 to RM 4.2
Middle River Right Bank at
RM 181.8 9/10/2012
4:23
PM
4:39
PM 0.0 4.2
Tributary 181.2 RM 0.0 to RM 1.8
Middle River Right Bank at
RM 181.2 9/10/2012
4:42
PM
4:51
PM 0.0 1.8
Fog Creek
RM 0.0 to RM
17.9
Middle River Left Bank at RM
176.6 9/10/2012
11:53
AM
1:33
PM 0.0 17.9
Fog Creek
Tributary L1 RM 7.3 to RM 0.0 Fog Creek at RM 5.2 9/10/2012
2:08
PM
2:31
PM 7.3 0.0
Devil Creek RM 0.0 to RM 2.5
Middle River Right Bank at
RM 161.5 9/7/2012
12:02
PM
12:12
PM 0.0 2.5
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 90 February 2013
Name Stream Section Confluence Date
Videotaped
Time
Start
Time
End
Rivermile
Start
Rivermile
End
Chinook Creek RM 0.0 to RM 3.1
Middle River Left Bank RM
157.0 9/12/2012
3:31
PM
4:49
PM 0.0 7.1
Cheechako Creek RM 0.0 to RM 1.8
Middle River Left Bank at RM
152.4 9/12/2012
5:14
PM
5:21
PM 0.0 1.8
Upper River
Mainstem
RM 184 to RM
233.5 -- 9/07-
08/2012
12:18
PM
3:15
PM -- --
Middle River
Mainstem
RM 98.5 to RM
184 -- 9/07 and
9/11/2012
12:00
PM
3:30
PM -- --
Lower River
Mainstem
RM 65.0 to RM
81.0 -- 9/12/2012
11:45
AM
2:00
PM -- --
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FERC Project No. 14241 Page 91 February 2013
6. FIGURES
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Figure 1 – Fish passage barriers survey extent and locations within the eastern half of the study area.
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Figure 2 – Fish passage barriers survey extent and locations within the western half of the study area.
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FERC Project No. 14241 Page 96 February 2013
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Figure 3 – Study Area map with streams where data were collected highlighted.
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FERC Project No. 14241 Page 98 February 2013
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Figure 4 – Jay Creek Reach Map.
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Figure 5 – Jay Creek Reach 1 Mesohabitat Survey.
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Figure 6 – Jay Creek Reach 2 Mesohabitat Survey.
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Figure 7 – Jay Creek Reach 6 Mesohabitat Survey.
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FERC Project No. 14241 Page 106 February 2013
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Figure 8 – Kosina Creek Reach Map.
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FERC Project No. 14241 Page 108 February 2013
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Figure 9 – Kosina Creek Reach 1 Mesohabitat Survey.
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FERC Project No. 14241 Page 110 February 2013
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Figure 10 – Kosina Creek Reaches 2 and 3 Mesohabitat Surveys.
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FERC Project No. 14241 Page 112 February 2013
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FERC Project No. 14241 Page 113 February 2013
Figure 11 – Kosina Creek Reach 4 Mesohabitat Units Surveyed.
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FERC Project No. 14241 Page 114 February 2013
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Figure 12 – Kosina Creek Reaches 5, 6, and 7 Mesohabitat Units Surveyed.
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FERC Project No. 14241 Page 116 February 2013
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Figure 13 – Kosina Creek Reach 8 Mesohabitat Units Surveyed.
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FERC Project No. 14241 Page 118 February 2013
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Figure 14 – Watana Creek Reaches.
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FERC Project No. 14241 Page 120 February 2013
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Figure 15 – Watana Creek Reach 1 Mesohabitat Units Surveyed.
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FERC Project No. 14241 Page 122 February 2013
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Figure 16 – Watana Creek Reaches 3 and 4 Mesohabitat Units Surveyed.
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FERC Project No. 14241 Page 124 February 2013
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Figure 17 – Watana Creek Reach 4 Mesohabitat Units Surveyed.
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Figure 18 – Watana Creek Reach 6 Mesohabitat Units Surveyed.
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FERC Project No. 14241 Page 128 February 2013
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Figure 19 – Example video capture of a tributary mid-channel scour pool in a confined channel
with boulder and cobble substrate and no stream wood visible.
Figure 20 – Example video capture of the Middle River in the vicinity of RM 100.5.
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FERC Project No. 14241 Page 130 February 2013
Figure 21 – Example video capture of the Lower River in the vicinity of RM 65.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 1 February 2013
Appendix A. Streams surveyed for fish passage barriers
Tributary RM 1 Tributary Name Tributary Length (mile) 2 Barrier(s) Present
150.1 Unnamed 1.03 Y
150.2 Unnamed Na Y
151.0 Unnamed Nab Y
152.0 Unnamed Na Y
152.4 Cheechako Creek 10.67 Y
153.4 Unnamed 1.63 Y
154.5 Unnamed 5.35 Y
154.6 Unnamed Na Y
155.3 Unnamed Na Y
157.0 Chinook Creek 10.61 Y
158.8 Unnamed Na Y
161.5 Devil Creek 15.83 Y
163.5 Unnamed 0.91 N
164.0 Unnamed 0.62 N
165.0 Unnamed Na Y
165.2 Unnamed Na Y
165.6 Unnamed 1.57 Y
166.3 Unnamed 5.36 N
167.5 Unnamed 2.55 N
168.7 Unnamed Na Y
171.0 Unnamed 3.37 Y
171.3 Unnamed 2.54 Y
172.1 Unnamed 1.04 N
172.8 Unnamed 4.75 N
173.0 Unnamed 5.39 Y
174.0 Unnamed 5.45 N
174.2 Unnamed 8.63 N
174.5 Unnamed Na N
175.1 Unnamed 2.67 N
175.4 Unnamed 1.17 N
176.6 Fog Creek 27.81 N
176.9 Unnamed 0.72 N
177.9 Unnamed 2.89 N
179.1 Unnamed 3.79 Y
179.2 Unnamed 5.17 N
181.2 Unnamed 10.40 Y
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 2 February 2013
Tributary RM 1 Tributary Name Tributary Length (mile) 2 Barrier(s) Present
181.8 Tsusena Creek 30.70 Y
182.8 Unnamed Na N
185.8 Unnamed 1.19 N
186.6 Deadman Creek 41.91 Y
186.9 Unnamed 1.82 Y
189.9 Unnamed 3.32 N
192.0 Unnamed 7.08 N
192.7 Unnamed 1.46 N
194.0 Unnamed Na N
194.1 Watana Creek 26.91 N
194.9 Unnamed 5.38 Y
195.8 Unnamed 2.70 N
196.2 Unnamed 1.23 N
197.7 Unnamed 0.96 N
198.5 Unnamed 0.91 N
200.7 Unnamed 3.08 Y
201.8 Unnamed 6.15 Y
203.7 Unnamed 0.52 N
204.8 Unnamed 0.47 N
205.0 Unnamed 0.55 N
206.3 Unnamed 1.50 N
206.8 Kosina Creek 39.48 N
207.0 Unnamed 1.82 N
208.6 Jay Creek 19.63 N
210.2 Unnamed 2.07 N
211.6 Unnamed 1.89 N
212.0 Unnamed 0.92 N
213.0 Unnamed 2.01 Y
213.2 Unnamed 2.35 N
215.1 Unnamed 3.17 N
217.5 Unnamed 1.78 N
219.2 Unnamed 5.08 N
220.8 Unnamed 2.69 N
221.0 Unnamed Na N
221.5 Unnamed 9.54 N
224.3 Unnamed 2.21 N
225.0 Unnamed 2.49 N
226.8 Unnamed 9.23 Y
227.4 Unnamed 1.31 N
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 3 February 2013
Tributary RM 1 Tributary Name Tributary Length (mile) 2 Barrier(s) Present
228.5 Unnamed 1.54 N
229.8 Unnamed 1.52 N
231.2 Goose Creek 25.16 N
233.5 Oshetna River 55.59 N
Notes:
1 Tributary streams are designated by the Susitna River historic river mile (RM) at the point of confluence. RMs
have been previously designated at one-mile intervals. The tenths increments were created by interpolating
between RMs in the Geographic Information System (GIS). If the river had many curves between RMs, the
RM listed here may not be accurate to the tenth of a mile.
2 Some streams were not mapped in the National Hydrology Dataset used in the GIS. These streams are likely
less than 1 mile in length.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 1 February 2013
Appendix B. Fish Passage Barriers – Photos
ID: PB150.1-A Tributary Name RM 150.1 -Unnamed Tributary
Lat. 62.81589495 Classification Compound
Long. 149.34939788 Vertical distance Estimated <10 ft
Notes:
Devils Canyon tributary on river left, Barrier just upstream from mouth, with cascades and
chutes above and below. Fish habitat limited by steep gradient, large substrate and limited
flows.
ID: PB150.2-A Tributary Name RM 150.2 - Unnamed Tributary
Lat. 62.81305533 Classification Complex chute
Long. 149.34386875 Vertical distance Not Measured
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 2 February 2013
Notes: Devils Canyon tributary on river left. Very small stream channel. Chute observed is a likely
barrier. Fish habitat limited by steep gradient, large substrate and limited flows.
ID: PB151.0-A Tributary Name RM 151.0 - Unnamed Tributary
Lat. 62.81536144 Classification Compound
Long. 149.32170373 Vertical distance Not Measured
Notes: Devils Canyon tributary on river left, steep, small stream with complex of chutes and falls . Fish
habitat limited by steep gradient, large substrate and limited flows.
ID: PB152.0-A Tributary Name RM 152.0 - Unnamed Tributary
Lat. 62.82655011 Classification Compound
Long. -149.30729105 Vertical distance 10
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 3 February 2013
Notes:
Devils Canyon tributary on river right. Small, steep right bank stream, mostly continuous
cascades/ boulders with chutes forming fixed permanent falls. Very little to no fish habitat due
to steep gradient, large substrate and low flows.
ID: PB152.4-A Tributary Name RM 152.4 - Cheechako Creek
Lat. 62.80752495 Classification Compound
Long. -149.28974974 Vertical distance Estimated 3-4 ft cascades
Notes:
Devils Canyon tributary on river left., Lowest potential barrier on Cheechako Creek. Fixed
feature, may be seasonally driven by velocity with limited resting zones in continuous
falls/cascades.
ID: PB152.4-B Tributary Name RM 152.4 - Cheechako Creek
Lat. 62.80096393 Classification Multiple Falls
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 4 February 2013
Long. -149.29625200 Vertical distance Estimated <10 ft
Notes: Devils Canyon tributary on river left, Falls are a fixed permanent feature. Potential plunge pool
barrier and limited landing zone or resting areas at falls crest.
ID: PB152.4-C Tributary Name RM 152.4 - Cheechako Creek
Lat. 62.79667441 Classification Single Falls
Long. -149.29798035 Vertical distance Estimated <10 ft
Notes:
Devils Canyon tributary on river left, this barrier is located above PB152.4-A and PB152.4-B.
Falls are a fixed permanent feature. Plunge pool (launch zone) probably adequate, but falls
height precludes passage.
ID: PB153.4-A Tributary Name RM 153.4 - Unnamed Tributary
Lat. 62.81374818 Classification Single Falls
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 5 February 2013
Long. -149.26381957 Vertical distance Estimated <10 ft
Notes: Devils Canyon tributary on river right, This large waterfall is a fixed permanent feature.
ID: PB154.5-A Tributary Name RM 154.5 - Unnamed Tributary
Lat. 62.80442172 Classification Multiple Falls
Long. -149.23537323 Vertical distance Estimated > 20 ft
Notes: Devils Canyon tributary on river left, this shooting and forceful falls on and incised cliff face is
a permanent feature..
ID: PB154.6-A Tributary Name RM 154.6 - Unnamed Tributary
Lat. 62.80194419 Classification Complex Chute
Long. -149.22433628 Vertical distance Estimated >10 ft
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 6 February 2013
Notes: Devils Canyon tributary or river left, this chute is a fixed permanent feature. Flows cascade
through continuous chutes over bedrock and provide no visible resting pools.
ID: PB155.3L-A Tributary Name RM 155.3L - Unnamed Tributary
Lat. 62.80351697 Classification Compound
Long. -149.21004421 Vertical distance Estimated 10 ft
Notes: Devils Canyon tributary on river left, falls drop about 10 feet into a chute. Habitat also included
runs and riffle through gentler gradient near flood plane.
ID: PB155.3L-B Tributary Name RM 155.3L - Unnamed Tributary
Lat. 62.80296779 Classification Single Falls
Long. -149.20975596 Vertical distance 12
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 7 February 2013
Notes: Devils Canyon tributary on river left, falls are a permanent fixed feature.
ID: PB155.3-C Tributary Name RM 155.3L - Unnamed Tributary
Lat. 62.80482807 Classification Compound
Long. -149.21028444 Vertical distance Not Measured
Notes: Devils Canyon tributary on river right, fixed permanent barrier formed from continuous boulder
cascades and falls. Few if any resting pools.
ID: PB157.0-A Tributary Name RM 157.0R1 - Chinook Creek right tributary
Lat. 62.78970653 Classification Single Falls
Long. -149.14252320 Vertical distance Estimated >10 ft
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 8 February 2013
Notes:
Devils Canyon tributary on river left, this f alls is located in the first right bank tributary of
Chinook Creek. Note, this prevents passage into this minor tributary of Chinook Creek,
however the main stem of Chinook Creek is unobstructed.
ID: PB158.8-A Tributary Name RM 158.8 - Unnamed Tributary
Lat. 62.80700158 Classification Compound
Long. -149.10483657 Vertical distance Estimated 30 ft
Notes: Devils Canyon tributary on river left, this small stream has continuous cascades, chutes, and
falls that are fixed and permanent features.
ID: PB161.5-A Tributary Name RM 161.5 - Devil Creek
Lat. 62.84993201 Classification Single Falls
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 9 February 2013
Long. -149.05053257 Vertical distance Estimated 80 ft
Notes: Middle River tributary on river right, this large and powerful waterfall is a fixed permanent
feature.
ID: PB161.5-B Tributary Name RM 161.1L1 - Devil Creek
Lat. 62.84898184 Classification Single Falls
Long. -149.04413332 Vertical distance Estimated 40 ft
Notes: Middle River tributary on river right, located a short distance up the first left tributary of Devil
Creek this falls is a fixed permanent feature.
ID: PB161.5-C Tributary Name RM 161.5R1 - Devil Creek
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 10 February 2013
Lat. 62.83612275 Classification Compound
Long. -149.06697921 Vertical distance Not Measured
Notes:
Middle River tributary on river right, this feature is located on the first right tributary of Devil
Creek. Continuous fast water through bedrock and boulder dominated high gradient chutes
with 3-5’ falls. Few if any resting areas and pool launch zones.
ID: PB165.0-A Tributary Name RM 165.0 - Unnamed Tributary
Lat. 62.79186479 Classification Single Falls
Long. -148.99124284 Vertical distance Estimated 10 ft
Notes: Middle River tributary on river right with small drainage basin and flow, permanent fixed falls on
high gradient bedrock and boulder dominated slope. No plunge pool at bottom for launch. .
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 11 February 2013
ID: PB165.2-A Tributary Name RM 165.2 - Unnamed Tributary
Lat. 62.78861395 Classification Compound
Long. -148.98724426 Vertical distance Estimated 10 ft
Notes: Middle River tributary on river right. Multiple falls with complex chutes and continuous
whitewater and no resting locations. Barrier is a fixed permanent feature.
ID: PB165.6-A Tributary Name RM 165.6 - Unnamed Tributary
Lat. 62.77677745 Classification Single Falls
Long. -149.02542533 Vertical distance Estimated 6 ft
Notes:
Middle River tributary on river left, potential barrier formed by fixed permanent falls with
cascades downstream. But pool at base of falls appears to have adequate depth and area.
Obstacle to fish movement but may not preclude upstream migration.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 12 February 2013
ID: PB168.7-A Tributary Name RM 168.7 - Unnamed Tributary
Lat. 62.77085261 Classification Compound
Long. -148.91471154 Vertical distance Not Measured
Notes: Middle River tributary on river right. Barrier is steep falls with cascade over bedrock on high
gradient stream.
ID: PB171.0-A Tributary Name RM 171.0 - Unnamed Tributary
Lat. 62.80180564 Classification Single Falls
Long. -148.82744847 Vertical distance Not Measured
Notes: Middle River tributary on river right, This falls is located on the left most third order tributary
near 3,000-foot elevation mark.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 13 February 2013
ID: PB171.0-B Tributary Name RM 171.0 - Unnamed Tributary
Lat. 62.79380126 Classification Single Falls
Long. -148.83939503 Vertical distance Not Measured
Notes: Middle River tributary river right, third order tributary near 3,000’ elevation. Falls with cascades
at tributary intersection along right bank form potential barrier.
ID: PB171.0-C Tributary Name RM 171.0 - Unnamed Tributary
Lat. 62.79336222 Classification Complex Falls
Long. -148.83839238 Vertical distance Measured > 10 ft
Notes: Middle River tributary on river right, This falls with boulder cascades is located on the first left
main tributary..
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 14 February 2013
ID: PB171.3-A Tributary Name RM 171.3 - Unnamed Tributary
Lat. 62.76574158 Classification Boulder Cascades
Long. -148.84428754 Vertical distance Not Measured
Notes: Middle River tributary on river left. This potential barrier is a very steep gradient cascade with
chutes located a short distance just upstream of the confluence with the Susitna.
ID: PB173.0-A Tributary Name RM 173.0 - Unnamed Tributary
Lat. 62.76887189 Classification Multiple Falls
Long. -148.79380007 Vertical distance Estimated >10 ft
Notes:
Middle River tributary on river right, This permanent fixed feature has m ultiple falls through split
bedrock and boulder channels. Plunge pool at bottom may have adequate depth, exit zone at
crest is a chute with fast turbulent flow.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 15 February 2013
ID: PB179.1-A Tributary Name RM 179.1 - Unnamed Tributary
Lat. 62.79672160 Classification Single Falls
Long. -148.58887335 Vertical distance Measured 15 ft
Notes: Middle River tributary on river left. Barrier is a single falls, which is a fixed permanent feature.
ID: PB181.2-A Tributary Name RM 181.2 - Unnamed Tributary
Lat. 62.84338357 Classification Single Falls
Long. -148.62792137 Vertical distance Estimate 30 ft
Notes: Middle River tributary on river right. Single fixed permanent waterfall located on the left (north)
tributary of this significant stream. The right (east) tributary is of similar size and lacks a barrier
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 16 February 2013
falls..
ID: PB181.8-A Tributary Name RM 181.8 - Tsusena Creek
Lat. 62.85418021 Classification Single Falls
Long. -148.55224796 Vertical distance Estimated 40 ft
Notes: Middle River tributary river right. Large permanent fixed falls.
ID: PB186.6-A Tributary Name RM 186.6 - Deadman Creek
Lat. 62.83697594 Classification Single Falls
Long. -148.46997228 Vertical distance Estimated 40ft
Notes:
Upper River tributary on river right above the proposed Susitna Watana dam. Large fixed
permanent falls, with fast, deep cascade and whitewater. Falls are located below the proposed
maximum pool elevation.
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 17 February 2013
ID: PB186.9-A Tributary Name RM 186.9 - Unnamed Tributary
Lat. 62.82265043 Classification Complex Chute
Long. -148.46660351 Vertical distance Not Measured
Notes:
Upper River tributary on river left upriver of the proposed Susitna Watana dam. Very shallow
cascade near mouth of tributary. Stream gradient increases just upstream to continuous
cascades over bedrock and boulder controlled chutes located very close to the proposed
maximum pool elevation. Small drainage basin and resulting low flow provide very limited
anadromous fish habitat.
ID: PB194.9-A Tributary Name RM 194.9 - Unnamed Tributary
Lat. 62.81438545 Classification Multiple Falls
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 18 February 2013
Long. -148.25308501 Vertical distance Measured 15 ft
Notes:
Upper River tributary on river left upstream of the proposed Susitna Watana dam. Multiple
falls are fixed and permanent features, located slightly below the maximum pool elevation.
There were no barriers observed upstream of this point.
ID: PB200.7-A Tributary Name RM 200.7 - Unnamed Tributary
Lat. 62.80094826 Classification Single Falls
Long. -148.07391445 Vertical distance Estimated 10 ft
Notes: Upper River tributary on river right upstream of the proposed Susitna Watana dam. Fixed
permanent single falls. The lowest of a series of falls below the maximum pool elevation.
ID: PB200.7-B Tributary Name RM 200.7 - Unnamed Tributary
Lat. 62.80216187 Classification Single Falls
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 19 February 2013
Long. -148.06896636 Vertical distance Estimated 40 ft
Notes: Upper River tributary on river right upstream of the proposed Susitna Watana dam. Fixed
permanent single falls. One of a series of falls below the maximum pool elevation.
ID: PB200.7-C Tributary Name RM 200.7 - Unnamed Tributary
Lat. 62.80234527 Classification Single Falls
Long. -148.06814351 Vertical distance Estimated >15’
Notes: Upper River tributary on river right upstream of the proposed Susitna Watana dam. Fixed
permanent single falls. One of a series of falls below the maximum pool elevation.
ID: PB200.7-E Tributary Name RM 200.7 - Unnamed Tributary
Lat. 62.80261927 Classification Single Falls
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 20 February 2013
Long. -148.06462730 Vertical distance Estimated 20 ft
Notes: Upper River tributary on river right upstream of the proposed Susitna Watana dam. Fixed
permanent single falls. The uppermost of a series of falls below the maximum pool elevation.
ID: PB213.0-A Tributary Name RM 213.0 - Unnamed Tributary
Lat. 62.74994580 Classification Single Falls
Long. -147.77635488 Vertical distance Estimated >6 ft
Notes:
Upper River tributary on river left upstream of the proposed Susitna Watana dam. Single fixed
permanent falls. Potential barrier as leaping distance may exce10 feet due to horizontal
distance from falls crest to plunge pool.
ID: PB226.8-A Tributary Name RM 226.8 - Unnamed Tributary
Lat. 62.69938029 Classification Compound
FINAL REPORT HABITAT REPORT
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 21 February 2013
Long. -147.44758763 Vertical distance Estimated 15 ft
Notes: Upper River tributary on river right upstream of the proposed Susitna Watana dam, Series of
falls over bedrock and boulder substrate forming a fixed and permanent feature.