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Susitna-Watana Hydroelectric Project Document
ARLIS Uniform Cover Page
Title:
Technical memorandum: Adjustments to middle river focus areas
SuWa 200
Author(s) – Personal:
Author(s) – Corporate:
R2 Resource Consultants, Inc.
AEA-identified category, if specified:
Final study plan
AEA-identified series, if specified:
Series (ARLIS-assigned report number):
Susitna-Watana Hydroelectric Project document number 200
Existing numbers on document:
Published by:
[Anchorage : Alaska Energy Authority, 2013]
Date published:
May 2013
Published for:
Alaska Energy Authority
Date or date range of report:
Volume and/or Part numbers:
Study plan Section 8.5B
Final or Draft status, as indicated:
Document type:
Pagination:
2, iii, 43 p.
Related work(s):
Pages added/changed by ARLIS:
Notes:
All reports in the Susitna-Watana Hydroelectric Project Document series include an ARLIS-
produced cover page and an ARLIS-assigned number for uniformity and citability. All reports
are posted online at http://www.arlis.org/resources/susitna-watana/
May 31, 2013
Ms. Kimberly D. Bose
Secretary
Federal Energy Regulatory Commission
888 First Street, NE
Washington, DC 20426
Re: Susitna-Watana Hydroelectric Project, FERC Project No. 14241-000;
Adjustments to Middle River Focus Areas Technical Memorandum
Dear Secretary Bose:
On April 1, 2013, the Federal Energy Regulatory Commission (Commission)
issued its Study Plan Determination (April 1SPD) for 14 of the 58 proposed individual
studies in the Alaska Energy Authority’s (AEA) Revised Study Plan (RSP) for the
Susitna-Watana Hydroelectric Project, FERC Project No. 14241 (Project).1 When
approving the Fish and Aquatics Instream Flow Study (Study 8.5), the Commission’s
April 1 SPD made the following recommendation:
We recommend that AEA: (1) consult with the [technical working group
(TWG)] and select an appropriate focus area within MR-2 to eliminate
from the study; (2) consult with the TWG and establish an additional focus
area in geomorphic reach MR-7 that is sufficient for conducting
interdisciplinary studies, possibly near Lower McKenzie Creek or below
Curry on old Oxbow II; and (3) file a detailed description of the changes
to the proposed focus area locations in MR-2 and MR-7 by May 31, 2013,
and include in the filing documentation of consultation with [National
Marine Fisheries Service (NMFS), U.S. Fish and Wildlife Service (FWS),
and Alaska Department of Fish and Game (Alaska DFG)], including how
the agency comments were addressed.2
AEA has completed these recommended tasks. A detailed description of the
changes to the proposed focus area locations in MR-2 and MR-7 is provided in the
Adjustments to Middle River Focus Areas Technical Memorandum, which appears as
Attachment A. This technical memorandum includes documentation of AEA’s
consultation with NMFS, FWS, and Alaska DFG, and a description of how the agency
comments were addressed.
1 Study Plan Determination on 14 remaining studies for the Susitna-Watana Hydroelectric Project,
Project No. 14241-000 (issued Apr. 1, 2013).
2 Id. at Appendix B, at B-92
2
As always, AEA appreciates the participation and commitment to this licensing
process demonstrated by Commission Staff, federal and state resource agencies, and
other licensing participants. AEA looks forward to working with licensing participants
and Commission Staff in implementing the approved studies, which AEA believes will
comprehensively investigate and evaluate the full range of resource issues associated
with the proposed Project and support AEA’s license application, scheduled to be filed
with the Commission in 2015.
If you have questions concerning this submission please contact me at
wdyok@aidea.org or (907) 771-3955.
Sincerely,
Wayne Dyok
Project Manager
Alaska Energy Authority
Attachment
cc: Distribution List (w/o Attachment)
Susitna-Watana Hydroelectric Project
(FERC No. 14241)
Technical Memorandum:
Adjustments to Middle River Focus Areas
Prepared for
Alaska Energy Authority
Prepared by
R2 Resource Consultants, Inc.
May 2013
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FERC Project No. 14241 Page i May 2013
TABLE OF CONTENTS
1. Introduction ........................................................................................................................1
1.1. Background ........................................................................................................1
1.2. Objectives ..........................................................................................................2
1.3. Selection Strategy ..............................................................................................3
2. MR-2 Focus Areas..............................................................................................................3
3. MR-7 Focus Areas..............................................................................................................4
3.1. Lane Creek and Upstream ..................................................................................4
3.2. Lower McKenzie Creek and Upstream ..............................................................5
3.3. Oxbow I and Upstream ......................................................................................5
3.4. Summary of Rejected MR-7 Options ................................................................6
4. Implications of Focus Area Adjustments .........................................................................7
5. Final FA Selections ............................................................................................................7
5.1. Focus Area Removed from MR-2 ......................................................................8
5.2. Focus Area Added to MR-7 ...............................................................................8
5.3. Focus Area 138 Boundary Revision ..................................................................8
6. References ...........................................................................................................................9
7. Tables ................................................................................................................................11
8. Figures ...............................................................................................................................18
9. Appendix 1. IFS TT Meeting notes, April 26, 2013
10. Appendix 2. focus area maps with macrohabitat classification types
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LIST OF TABLES
Table 1. Locations, descriptions and selection rationale of 10 Proposed Focus Areas identified
for detailed study in the Revised Study Plan, Middle River Segment of the Susitna River
(AEA 2012). Focus Area identification numbers (e.g., Focus Area 184) represent the
truncated Project River Mile (PRM) at the downstream end of each Focus Area. ............... 12
Table 2. Metrics used to compare the representation and proportionality of habitat types for
Focus Areas within each geomorphic reach. ........................................................................ 13
Table 3. Proportionality metrics for existing and alternate Focus Area options in comparison to
total geomorphic reach values in MR-2 and MR-7 based on 2012 habitat mapping (HDR
2013). .................................................................................................................................... 14
Table 4. 1980s peak spawner counts. Source: ADF&G 1981, ADF&G 1983, Barrett et al. 1984,
Barrett et al. 1985, Thompson et al. 1986. ............................................................................ 15
Table 5. Locations, descriptions and selection rationale of 10 Final Focus Areas identified for
detailed study in the Middle River Segment of the Susitna River. Focus Area identification
numbers (e.g., Focus Area 184) represent the truncated Project River Mile (PRM) at the
downstream end of each Focus Area. ................................................................................... 16
Table 6. Lengths of final Focus Areas as proportion of each Geomorphic Reach. ..................... 17
LIST OF FIGURES
Figure 1. Map of the Middle Segment of the Susitna River depicting the eight Geomorphic
Reaches and original locations of and potential changes to Focus Areas. No Focus Areas
have been proposed in MR-3 and MR-4 due to safety issues related to sampling within or
proximal to Devils Canyon. .................................................................................................. 19
Figure 2. Map showing habitat mapping for geomorphic reach MR-2 (HDR 2013). ................. 20
Figure 3. Map showing Focus Area 115 beginning at Project River Mile 115.3 and extending
upstream to PRM 116.5. This Focus Area is located about 0.6 miles downstream of Lane
Creek and consists of side channel and upland slough habitats including Slough 6A. ........ 21
Figure 4. Map of geomorphic reach MR-7 highlighting side sloughs and tributary features not
captured by existing FA-115. ................................................................................................ 22
Figure 5. Map showing habitats mapped in the Lane Creek area. ............................................... 23
Figure 6. Map showing habitats mapped in the McKenzie Creek area. ...................................... 24
Figure 7. Map showing habitats mapped in the Oxbow I area. ................................................... 25
APPENDICES
Appendix 1. IFS TT Meeting Notes, April 26, 2013
Appendix 2. Focus Area Maps with Macrohabitat Classification Types
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LIST OF ACRONYMS AND ABBREVIATIONS
Abbreviation Definition
ADF&G Alaska Department of Fish and Game
AEA Alaska Energy Authority
FA Focus Area
FERC Federal Energy Regulatory Commission
IFSTT Instream Flow Study Technical Team
MR Middle River
PRM Project river mile
Project Susitna-Watana Hydroelectric Project, FERC Project No. 14241
RSP Revised Study Plan
SPD Study Plan Determination
TWG Technical Workgroup
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1. INTRODUCTION
On April 1, 2013 the Federal Energy Regulatory Commission (FERC) issued its Study Plan
Determination (SPD) for 14 of the 58 proposed individual studies in the Alaska Energy
Authority’s (AEA) Revised Study Plan (RSP) for the Susitna-Watana Hydroelectric Project,
FERC Project No. 14241 (Project). When approving the Fish and Aquatics Instream Flow
Study (Study 8.5), FERC’s April 1 SPD made the following recommendation:
We recommend that AEA: (1) consult with the TWG and select an appropriate
focus area within MR-2 to eliminate from the study; (2) consult with the TWG and
establish an additional focus area in geomorphic reach MR-7 that is sufficient for
conducting interdisciplinary studies, possibly near Lower McKenzie Creek or
below Curry on old Oxbow II; and (3) file a detailed description of the changes to
the proposed focus area locations in MR-2 and MR-7 by May 31, 2013, and
include in the filing documentation of consultation with NMFS, FWS, and Alaska
DFG, including how the agency comments were addressed.
AEA has completed these recommended tasks. As recommended, this technical memorandum
provides the detailed description of the changes to the proposed focus area locations in MR-2
and MR-7 is provided in the Adjustments to Middle River Focus Areas Technical Memorandum.
In the March 26-27, 2013 Technical Workgroup (TWG) meetings, a series of Instream Flow
Study Technical Team (IFSTT) meetings were proposed to allow agency and AEA scientists to
confer on technical details and address agency comments and concerns regarding planned 2013-
2014 sampling and analysis issues.
During the April 26, 2013 IFSTT meeting, consistent with the FERC recommendation, AEA
conferred with the TWG representatives concerning the changes to the Focus Area locations (see
Meeting Notes in Appendix 1).
An earlier version of this technical memorandum was developed to evaluate potential responses
to the FERC recommendation and to serve as a starting point for the IFSTT discussion on April
26. The earlier version provided background information on potential adjustments to Focus
Areas (FAs) in the Middle River (MR) Segment, but did not propose a specific action. The
earlier version contained information on the distribution of habitat types and fish species in the
affected geomorphic reaches and in potential new study areas to serve as a guide in evaluating
alternative FA revisions.
This technical memorandum contains some additional background information that was used in
evaluating the candidate FAs, presents the results of the IFSTT meeting, and describes AEA’s
adjustments to FA locations. Maps of the ten final MR Focus Areas are provided in Appendix 2.
1.1. Background
Preliminary habitat mapping of the Middle River Segment of the Susitna River was completed in
2013 using a combination of geo-rectified aerial imagery (2011 Matsu Ortho Imagery at 1:8000
scale. http://matsu.gina.alaska.edu/wms/imagery) in combination with High Definition aerial
videography that was taken of the river in August 2012 (≈ 10,000 cfs) (HDR 2013). The results
of the habitat mapping provided a spatial depiction of the distribution of habitat types and
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features throughout the entire length of the Middle River Segment. Specific habitat types were
digitized using ARC GIS and lineal distances computed of each discrete habitat feature.
Selection criteria for the ten original FAs in the Middle River considered the following:
All major habitat types (main channel, side channel, side slough, upland slough, tributary
delta) should be sampled within each geomorphic reach.
At least one (and up to three) FA(s) per geomorphic reach (excepting geomorphic reaches
associated with Devils Canyon – MR-3 and MR-4) that is/are representative of other
areas should be studied.
Areas that are known (based on existing and contemporary data) to be biologically
important for salmon spawning and/or rearing will be sampled (i.e., critical areas).
Some areas for which little or no fish use has been documented, or for which information
on fish use is lacking, will also be sampled.
The ten original FAs are detailed in Table 1 and displayed in Figure 1.
In the previous FA technical memorandum (R2 Resource Consultants 2013a), results of the
preliminary habitat mapping were used to evaluate the “representativeness” of the proposed FAs
with respect to other areas of the river. In this context, representativeness specifically refers to
how well habitat units within the FAs represent habitat units outside of these areas within the
same geomorphic reach. A suite of scaled metrics were identified and developed that were used
in a comparative analysis of the representativeness of habitat types within and outside of FAs
(Table 2).
Representativeness was examined by 1) comparing the representation of habitat types within the
FAs to the representation of habitat types in the entire geomorphic reach; 2) determining if the
habitat types have been proportionately represented (focus vs. non-focus areas); 3) determining if
there was a bias in the habitat types that were selected in the FAs; and 4) evaluating whether a
random systematic approach in the selection of FAs would yield different results than the
selection process and criteria applied to the current FAs.
The technical memorandum concluded that the set of FAs was generally representative, although
some habitat types in some geomorphic reaches were not represented. There was no evidence of
bias towards specific habitats in the selection of FAs, and a systematic random selection of FAs
would not have been perceptibly better in terms of representativeness or bias.
1.2. Objectives
The objective of this technical memorandum is to describe the background material and rationale
used to support AEA’s decision to move one of the MR-2 FAs proposed in the RSP to
Geomorphic Reach MR-7. AEA discussed the implications of several options with the TWG
and sought the input of the TWG during the April 26, 2013 meeting.
Specific objectives of this technical memorandum include:
Describe options for eliminating one of the MR-2 FAs;
Describe options for adding a FA to MR-7, including:
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o Modeling an area “near Lower McKenzie Creek” as recommended by agency
comments (FERC 2013, p B-89);
o Modeling an area “below Curry on Old Oxbow II” as recommended by agency
comments (FERC 2013, p B-89);
o Modeling an area that includes the Lane Creek confluence, either by establishing
a new FA or by expanding FA-115;
o Modeling other areas such as the Chase Creek confluence (Project river mile
[PRM] 110.5), Old Oxbow I (PRM 113.7), or other areas identified in
consultation with the TWG.
Describe the final FA boundaries, including the relocation of one FA from Geomorphic
Reach MR-2 to MR-7 and minor revisions to the boundaries of FA138.
1.3. Selection Strategy
The underlying strategy applied in the selection of the FA to eliminate from MR-2 was to
minimize the detrimental impact to the quality of the overall study, including considerations of
habitat representativeness and impacts to study plans other than Fish and Aquatics IFS.
The strategy for selecting the new FA to be added to MR-7 considered 1) the agency concerns as
outlined in the FERC determination (2013), and 2) the representativeness of FAs in MR-7 in
terms of habitat types.
2. GEOMORPHIC REACH MR-2 FOCUS AREAS
Two FAs were originally proposed within Geomorphic Reach MR-2, FA-173 and FA-171.
These FAs were selected based on their representativeness of the reach and the inclusion of a
mix of side channel and slough habitat types. There is no existing fish information within these
areas because they were not sampled in the 1980s.
The habitats present in Geomorphic Reach MR-2 and the representativeness and proportionality
of the habitats in the two existing FAs are presented in Table 3.
FA-173 is 1.8 miles long and is comprised of single main channel, side channel, side slough, and
upland slough habitats, and includes a tributary and tributary mouth (Figure 2, Table 3). It is the
more complex of the two FAs in MR-2 in terms of habitat, and based on selected metrics is more
representative of MR-2 than the other FA (Table 3). FA-173 is also a planned study area for
River Productivity.
FA-171 is 1.4 miles long and is comprised of single main channel and side slough habitat, and
contains one tributary (Figure 2, Table 3). Each of these habitat types is also represented in FA-
173. Plant communities in FA-171 are represented in other Focus Areas. If FA-171 were the
only FA in MR-2, side channel and upland slough habitat in MR-2 would not be represented for
the modeling results. Also, there would be no mapped tributary mouths. However, FA-171 was
specifically selected for representing the simple mainstem channel type without off-channel
habitats prevalent in MR-1 and MR-2. Without FA-171, this type of habitat is underrepresented.
Options considered for representing this type of habitat include 1) extending the lower boundary
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of FA-173 to include a stretch of simpler channel type; 2) use model results from FA-184 in MR-
1 to represent the simple channel in geomorphic reach MR-2; or 3) adjusting the weighting of the
length of simple channel available in FA-173.
3. GEOMORPHIC REACH MR-7 POTENTIAL FOCUS AREAS
One FA was originally proposed within Geomorphic Reach MR-7 (Figure 3), FA-115. This FA
includes Slough 6A, which, based on the 1980s studies, provides high-use juvenile rearing
habitat and also includes side channel, upland slough, backwater, split main channel, and single
main channel habitats. Habitats within the Slough 6A feature were included in the FA to allow
comparison to 1980s data.
In the previous focus area technical memorandum (R2 Resource Consultants 2013a), it was
noted that this FA did not capture all mapped habitat types within MR-7 (Table 3). Specifically,
there is no side slough habitat in FA-115, and no tributary mouths or plumes identified by
preliminary habitat mapping (HDR 2013).
There is a total of approximately 3,000 meters of habitat classified as side slough in Geomorphic
Reach MR-7 (Figure 4). Two of the tributary mouths and the single plume in MR-7 identified by
the habitat mapping are associated with the Lane Creek area; the other tributary mouth is
associated with an unnamed tributary at PRM 113.7 near Oxbow I.
Two areas were suggested in agency comments and the FERC Determination as potential FAs in
MR-7. One area is “below Curry on old Oxbow II.” Oxbow II is near PRM 123, and is
contained in Geomorphic Reach MR-6. Therefore, creating a new FA containing Oxbow II
would not be a choice that is responsive to the FERC recommendations for increasing the
proportional length represented by FAs in MR-7.
In this section, AEA reviews three possibilities for adding a FA in MR-7:
Lane Creek area (Figure 5);
Lower McKenzie Creek area (Figure 6); and
Oxbow I area (Figure 7).
AEA also summarizes other alternatives that were considered but rejected.
3.1. Lane Creek and Upstream
The Lane Creek channel bifurcates before entering the main channel of the Susitna River,
yielding two tributary mouths and a mapped clearwater plume (Figure 5). There is side slough
habitat with (unmapped) beaver complex activity just upstream of Lane Creek.
Lane Creek was utilized by chum, coho, and pink salmon for spawning during the 1980s (Table
4). During 1981, Chinook salmon fry were captured at the mouth of Lane Creek. During 1982,
Dolly Varden, longnose sucker, humpback whitefish, round whitefish, burbot, Arctic grayling,
and rainbow trout were found in Lane Creek and Side Slough 8. During 1983, juvenile Chinook,
juvenile coho, chum, and juvenile sockeye salmon were found in Side Slough 8 (Dugan et al.
1984), and the results of habitat surveys and water quality measurements are available for Lane
Creek and Slough 8 from the 1980s studies.
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During 2012 field surveys, coho and sockeye fry were observed in the mouth of Lane Creek, and
there were many coho fry in Side Slough 8 (R2 Resource Consultants 2013b).
If the Lane Creek area is selected as a new FA in MR-7, there would be substantial improvement
in representativeness of mapped habitat types in the reach for instream flow modeling (Table 3),
and there appears to be high fish use of the area. However, this area is just 0.5 miles upstream of
the existing FA-115, so the two FAs would be spatially co-located.
3.2. Lower McKenzie Creek and Upstream
The Lower McKenzie Creek area was suggested as a potential site in agency comments, and it
has mapped side slough habitats (Figure 6, Table 3). It has no mapped tributary mouths or
clearwater plumes, but there are several small tributaries that may have currently un-mapped
delta areas or plumes. The mapped side slough habitat is all contained in an island complex
(Figure 6). Lower McKenzie Creek is mapped as an upland slough at the mouth, but it appears
to be a small spring-fed tributary which is affected by beaver activity.
Lower McKenzie Creek was not sampled during the 2012 field season. However, it was utilized
by substantial numbers of adult pink and coho salmon for spawning during the 1980s studies,
and also by a few chum salmon (Table 4). Upper McKenzie Creek and Little Portage Creek are
also used for spawning by these species, but at much lower levels. Very little sampling occurred
at the tributary mouths of Little McKenzie, Little Portage, or Upper McKenzie Creek for juvenile
salmonids or resident fish. During 1982, resident fish including Arctic grayling, burbot, round
whitefish, longnose sucker, and slimy sculpin were captured in the mouth of Upper McKenzie
Creek and nearby main channel habitat (Schmidt et al. 1983).
If Lower McKenzie Creek was selected as the new FA in MR-7, it could potentially improve the
representativeness of modeled habitat types (Table 3), although this is not assured. For example,
the mapped side slough in the island complex may not be representative of other side sloughs.
The tributaries are not large and do not have mapped mouths or plumes. There is less
information about fish use of this potential FA compared to the Lane Creek area, but resident
fish and spawning was observed in this area in the 1980s.
Another concern with the selection of Lower McKenzie Creek is the proximity of the Alaska
Railroad to the east bank of the river. Access restrictions would inhibit side habitat sampling.
The railroad cuts through all tributary habitats in this area, including Lower McKenzie Creek and
Little Portage Creek.
3.3. Oxbow I and Upstream
The feature named Oxbow I is currently mapped as a side channel with an associated upland
slough complex at PRM 113.7 (Figure 7). The Oxbow I feature conveys flow during the open-
water season but becomes appreciably dewatered during periods of low flow. The Oxbow I
channel is characterized by shallow depths, lower velocities, and smaller streambed materials
than adjacent main channel habitats. The main channel at the upper end of the Oxbow I feature
contains vegetated islands divided by subchannels characterized as main channel splits or side
channels depending on the flow volume. A FA established to encompass the right bank oxbow
habitats could also include the unnamed tributary mouth on the left bank at PRM 113.7, and the
Gash and Slash Creek tributaries.
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The Oxbow I area was not sampled in 2012, but the Oxbow I feature and Gash and Slash creeks
were both sampled in the 1980s studies. Barrett et al. (1985) identified a chum spawning area in
Oxbow I during 1984, but the number of fish observed was not reported.
Spawning surveys from the 1980s studies reported pink salmon in both Gash and Slash creeks in
small numbers (Table 4). Coho salmon were present in Gash Creek in substantial numbers
during 1981 to 1984 (Barrett et al. 1984). Barrett et al. (1984) also reported there is a culvert
pipe under the railroad with a 2-foot waterfall near the mouth of the creek. Pink salmon were
spawning below the culvert and at the mouth of Gash Creek. A few chum salmon and coho were
observed to spawn in Slash Creek during 1985 (Thompson et al. 1986). There were no
observations of sockeye salmon or Chinook salmon in either stream during the 1980s. The main
channel near Oxbow I was sampled as a Selected Habitat Site during 1982 (Schmidt et al. 1983).
Juvenile Dolly Varden and round whitefish were captured at the mouth of Gash Creek, as were
Arctic lamprey adults and ammoceotes.
Selecting the Oxbow I area as the new FA in MR-7 would add the Oxbow I feature, several
tributary mouths, and divided main channel habitats to improve representativeness of modeled
habitat types (Table 3). This FA would also include important chum and coho salmon spawning
areas. The railroad property is close to the bank in this area, and it cuts directly across Gash
Creek with a small culvert. This potential FA is located immediately downstream of existing
FA-115.
3.4. Summary of Rejected Potential MR-7 Focus Area Options
The options described in the previous sections are not meant to be exhaustive, and combinations
of moving boundaries and adding a FA could accomplish diverse goals. Three locations that
were reviewed and rejected are described below.
The area around Chase Creek (approx. PRM 110.5; Figure 4) was identified as a spawning area
for coho and pink salmon and a few Chinook salmon in the 1980s. During the period 1981
through 1985, the highest annual peak spawner counts were 239 coho salmon, 438 pink salmon,
and 15 Chinook salmon (Barrett at al. 1985). However, macrohabitat types in the vicinity of
Chase Creek are also represented in FA-104, so this area was removed from consideration.
Another reviewed option was adding the Lane Creek area as a FA (Figure 5), or extending the
upper boundary of FA-115 approximately 0.6 miles to include the Lane Creek tributary mouth.
The Lane Creek area is a documented fish use area, with mapped tributary plumes and a side
slough complex (Slough 8). However, after closely reviewing available information, the IFSTT
did not think Slough 8 should be currently considered a side slough because the inlet connection
appears to have built up in elevation. The vegetation at the inlet area and within this lateral
habitat feature suggests that connection to the Susitna River at the upper end of the slough has
been lost. This area was considered by the IFSTT to be less critical in terms of fish use when
compared to the Oxbow I area.
The final reviewed option was adding the McKenzie Creek area as a FA (Figure 6). This area
has documented fish presence, and contains a large island channel complex with crossover
channels currently classified as side sloughs. However, there was disagreement within the
IFSTT as to how these habitat features should be classified. Some members of the IFSTT
suggested that the crossover channels may not provide high-quality fish rearing or spawning
habitat. McKenzie Creek and Little Portage creeks are small and do not contain mapped
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tributary plumes. In addition, access to the left bank of the area would be difficult because of the
close proximity of railroad property.
4. IMPLICATIONS OF FOCUS AREA ADJUSTMENTS
The effect of eliminating a FA in MR-2 and adding a FA in MR-7 will differ among instream
flow-related disciplines.
FA-171 represents a simple, single channel area that did not appear to be heavily influenced by
tributary inflow, groundwater contributions, or complex riparian habitats. Preliminary
evaluations suggest that MR-2 between the proposed dam site and Devils Canyon may remain
ice-free during the winter months under post-Project operations, which would reduce the
complexity of ice process-related studies.
Because a new FA in MR-7 will contain complex habitats, study efforts may be greater due to
higher data needs and modeling requirements associated with tributary deltas, groundwater, ice
processes, fish barriers, and water quality considerations.
RSP Section 8.6: The riparian instream flow study efforts will not be impacted by FA
adjustments, because the plant communities in FA-171 are represented in other Focus Areas.
RSP Section 9.6: The elimination of FA-171 will have little impact to fish distribution and
abundance sampling in MR-2 other than a redistribution of selected sampling locations inside
and outside of FAs. While there may be a reduction in cost of travel and logistics at a site in
MR-7, the sampling cost will be greater due to the larger, more complex sampling area. Adding
a FA to MR-7 will cause a redistribution of sampling effort inside and outside of FAs, and will
add to sampling effort in terms of additional habitat types that were not previously available in
FAs in MR-7. In addition, if the new FA is also added as a sample site for early life history
studies for Fish Distribution and Abundance in the Middle and Lower River (RSP 9.6), it will
add considerable effort to sampling for fish emergence.
RSP Section 9.8: The River Productivity Study will not be impacted by the elimination of FA-
171 because study efforts in MR-2 are concentrated at FA-173. The addition of a new FA in
MR-7 will not affect river productivity study efforts since there are no study sites within that
reach.
5. FINAL FOCUS AREA SELECTIONS
The IFSTT meeting held April 26, 2013 included participants from AEA, USFWS, NMFS,
USGS, ADF&G, and consultants representing these agencies. The meeting record is included in
Appendix 1.
Based upon the input from the IFSTT meeting, AEA has implemented the final FA decisions
from that meeting and has also made a minor revision to the boundary of FA-138. Table 5
contains an updated summary description of the final MR Focus Areas. Table 6 summarizes the
final FA lengths as proportions of the length of each Geomorphic Reach. Maps of each final FA
with preliminary habitat classifications are included in Appendix 2.
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5.1. Focus Area Removed from Geomorphic Reach MR-2
AEA will eliminate FA-171 as a FA, leaving FA-173 as the sole Focus Area in Geomorphic
Reach MR-2. AEA will adjust the weighting of the length of simple channel available in FA-
173. This adjustment should be sufficient for capturing the simple habitat features available in
MR-2. The IFSTT participants supported this change.
5.2. Focus Area Added to Geomorphic Reach MR-7
After considering the merits of each potential new FA for MR-7, AEA supports the IFSTT
recommendation to select the Oxbow I area as the new, additional MR-7 Focus Area, henceforth
labeled FA-113 (Figure 7). FA-113 will encompass 1.7 miles of MR-7 extending from PRM
113.6 to PRM 115.3. The downstream boundary of FA-113 will be located immediately below
the confluence of the left bank tributary (PRM 113.7) and below the right bank confluence of the
Oxbow 1 feature. FA-113 will extend upstream to encompass the entire Oxbow 1 feature and
the mouths of left bank Slash and Gash creeks.
Selecting FA-113 to represent MR-7 habitat provides additional examples of macrohabitat types
present in MR-7 including a side channel, upland slough, divided main channel islands, and
multiple small tributary mouths. When considered together, the two MR-7 Focus Areas will
encompass the variety of habitats found in MR-7. The proportion of Geomorphic Reach MR-7
that will be included in FAs and 2-D modeled will increase from 8 percent to 19 percent (Table
6).
The IFSTT participants supported this change. The IFSTT participants expressed interest in the
Oxbow I area from a fish perspective. The new FA contains habitats that supported salmon
spawning and rearing habitats in the 1980s. Both Gash Creek and Slash Creek are recognized as
anadromous fish waters in the ADF&G catalog. Gash Creek was identified in the 1980s as a
primary coho spawning tributary. Oxbow I is thought to be a critical chum salmon rearing
ground. Although the upper boundary of this new FA (FA-113) is effectively the lower
boundary of the existing FA-115, the two FAs will be considered as separate units for reporting
purposes.
5.3. Focus Area FA-138 Boundary Revision
The downstream boundary of FA-138 (Gold Creek Area, Figure 2-6) has been modified and
moved downstream from PRM 138.7 to PRM 138.5. For 2-D hydraulic modeling, a Focus Area
boundary perpendicular to flow with consistent water surface elevation across each channel is
preferred. The previous downstream boundary for FA-138 was cut along a cross-over channel
where flow could be moving laterally and the water surface elevation dropping along the
channel. The new boundary cuts across three distinct channel types which could have different
water surface elevations among channels, but a similar water surface elevation within each
channel.
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6. REFERENCES
ADF&G (Alaska Department of Fish and Game). 1981. Adult anadromous fisheries project
ADF&G/Su Hydro 1981. Phase I Final Draft Report, Susitna Hydro Aquatic Studies.
Prepared for Alaska Power Authority, Anchorage, Alaska. 467 pp. APA Document #
324.
ADF&G. 1983. Adult anadromous fish studies, 1982, Volume 2. Susitna Hydro Aquatic
Studies Phase II data report. Prepared for Alaska Power Authority, Anchorage, Alaska.
275 pp. + appendices. APA Document #s 588, 589.
AEA (Alaska Energy Authority). 2012. Revised study plan. Susitna-Watana Hydroelectric
Project, FERC No. 14241. Submitted to the Federal Energy Regulatory Commission,
December 2012. Prepared by Alaska Energy Authority, Anchorage, Alaska.
Barrett, B. M., F. M. Thompson and S. N. Wick. 1984. Adult anadromous fish investigations:
May-October, 1983. Report No. 1, Alaska Department of Fish and Game Susitna Hydro
Aquatic Studies. Prepared for the Alaska Power Authority, Anchorage, Alaska. 430 pp.
APA Document # 1450.
Barrett, B. M., F. M. Thompson and S. N. Wick. 1985. Adult salmon investigations: May-
October, 1984. Report No. 6, Alaska Department of Fish and Game Susitna Hydro
Aquatic Studies. Prepared for the Alaska Power Authority, Anchorage, Alaska. 528 pp.
APA Document # 2748.
Dugan, L. J., D. A. Sterritt, and M. E. Stratton. 1984. The distribution and relative abundance of
juvenile salmon in the Susitna River drainage. Pages 75-131 in Schmidt, D.C., S.S. Hale,
D.L. Crawford, and P.M. Suchanek, eds., Resident and juvenile anadromous fish
investigations (May-October 1983). Report No. 2, Alaska Department of Fish and Game
Susitna Hydro Aquatic Studies. Prepared for Alaska Power Authority, Anchorage,
Alaska. APA Document # 1784.
FERC (Federal Energy Regulatory Commission). 2013. Study plan determination on 14
remaining studies for the Susitna-Watana Hydroelectric Project. Letter to Alaska Energy
Authority, April 1, 2013.
HDR. 2013. Middle Susitna River Segment remote line habitat mapping technical memo.
Prepared for Alaska Energy Authority, Anchorage, Alaska.
R2 Resource Consultants, Inc. 2013a. Technical Memorandum, Selection of Focus Areas and
study sites in the Middle Susitna River for instream flow and joint resource studies –
2013 and 2014. Prepared for Alaska Energy Authority. March 1, 2013.
R2 Resource Consultants, Inc. 2013b. Summary review of Susitna River aquatic and instream
flow studies conducted in the 1980s with relevance to proposed Susitna – Watana Dam
Project – 2012: A Compendium of Technical Memoranda. Prepared for Alaska Energy
Authority. March 19, 2013.
Schmidt, D., S. Hale, D. Crawford, and P. Suchanek. 1983. Resident and juvenile anadromous
fish studies on the Susitna River below Devil Canyon, 1982. Volume 3, Phase II Basic
Data Report, Alaska Department of Fish and Game Susitna Hydro Aquatic Studies.
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Prepared for Alaska Power Authority, Anchorage, Alaska. 303 pp. + appendices. APA
Documents #s 486, 487.
Thompson, F. M., S. N. Wick, and B. L. Stratton. 1986. Adult salmon investigations, May –
October 1985. Report No. 13, Volume 1, Alaska Department of Fish and Game Susitna
Hydro Aquatic Studies. Prepared for Alaska Power Authority, Anchorage, Alaska. 173
pp. APA Document # 3412.
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7. TABLES
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority FERC Project No. 14241 Page 12 May 2013 Table 1. Locations, descriptions and selection rationale of 10 Proposed Focus Areas identified for detailed study in the Revised Study Plan, Middle River Segment of the Susitna River (AEA 2012). Focus Area identification numbers (e.g., Focus Area 184) represent the truncated Project River Mile (PRM) at the downstream end of each Focus Area. Focus Area ID Common Name Description Geomorphic Reach Location (PRM) Area Length (mi) Habitat Types Present Fish use in 1980s Instream Flow Studies in 1980s Rationale for Selection Main Channel, Single Main Channel, Split Side Channel Tributary Mouth Side Slough Upland Slough Beaver Complex Upstream Downstream Spawning Rearing IFG DIHAB RJHAB FA-184 Watana Dam Area approximately 1.4 miles downstream of dam site MR-1 185.7 184.7 1.0 X X X N/A N/A N/A N/A N/A FA-184 length comprises 50% of MR-1 reach length (2 miles long) and contains split main channel and side channel habitat present in this reach. FA-173 Stephan Lake, Complex Channel Wide channel near Stephan Lake with complex of side channels MR-2 175.4 173.6 1.8 X X X X N/A N/A N/A N/A N/A FA-173 contains a complex of main channel and off-channel habitats within wide floodplain. Represents greatest channel complexity within MR-2. Reach MR-2 is 15.5 miles long and channel is generally straight with few side channels and moderate floodplain width (2-3 main channel widths). FA-171 Stephan Lake, Simple Channel Area with single side channel and vegetated island near Stephan Lake MR-2 173.0 171.6 1.4 X X X N/A N/A N/A N/A N/A The single main channel with wide bars, single side channel and moderate floodplain channel width in FA-171 are characteristic of MR-2. Reach MR-2 channel morphology is generally straight with few side channels and moderate floodplain width (2-3 main channel widths). FA-151 Portage Creek Single channel area at Portage Creek confluence MR-5 152.3 151.8 0.5 X X X X FA-151 is a single main channel and thus representative of the confined Reach MR-5. Portage Creek is a primary tributary of the Middle Segment and the confluence supports high fish use. FA-144 Side Channel 21 Side channel and side slough complex approximately 2.3 miles upstream Indian River MR-6 145.7 144.4 1.3 X X X X X X X X X FA-144 contains a wide range of main channel and off-channel habitats, which are common features of Reach MR-6. Side Channel 21 is a primary salmon spawning area. Reach MR-6 is 26 miles long (30% of Middle Segment length) and is characterized by a wide floodplain and complex channel morphology with frequent channel splits and side channels. FA-141 Indian River Area covering Indian River and upstream channel complex MR-6 143.4 141.8 1.6 X X X X X X X X X FA-141 includes the Indian River confluence and a range of main channel and off-channel habitats. High fish use of the Indian River mouth has been documented and DIHAB modeling was performed in main channel areas in the 1980s. Studies in the 1980s did not document high fish use of lateral habitats on the right bank upstream of the Indian River confluence. FA-138 Gold Creek Channel complex including Side Channel 11 and Slough 11 MR-6 140.0 138.7 1.3 X X X X X X X X X The FA-138 primary feature is a complex of side channel, side slough and upland slough habitats, each of which support high adult and juvenile fish use. Complex channel structure of FA-138 is characteristic of Reach MR-6. IFG modeling was performed in side channel habitats in the 1980s. FA-128 Skull Creek Complex Channel complex including Slough 8A and Skull Creek side channel MR-6 129.7 128.1 1.6 X X X X X X X X X FA-128 consists of side channel, side slough and tributary confluence habitat features that are characteristic of the braided MR-6 reach. Side channel and side slough habitats support high juvenile and adult fish use and habitat modeling was completed in side channel and side slough habitats. FA-115 Lane Creek Area 0.6 miles downstream of Lane Creek, including Upland Slough 6A MR-7 116.5 115.3 1.2 X X X X X X X X FA-115 contains side channel and upland slough habitats that are representative of MR-7. Reach MR-7 is a narrow reach with few braided channel habitats. Upland Slough 6A is a primary habitat for juvenile fish and habitat modeling was done in side channel and upland slough areas. FA-104 Whiskers Slough Whiskers Slough Complex MR-8 106.0 104.8 1.2 X X X X X X X X X X X FA-104 contains diverse range of habitat, which is characteristic of the braided, unconfined Reach MR-8. FA-104 habitats support juvenile and adult fish use and a range of habitat modeling methods were used in side channel and side slough areas.
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Table 2. Metrics used to compare the representation and proportionality of habitat types for Focus Areas within each
geomorphic reach.
Level Habitat Type Comparison Metric Numerator Denominator
Macro-
Habitat
Main Channel Percent of main channel that
is single unsplit main channel
Length of main channel
habitat (HDR)
Total length of main
channel (thalweg, R2)
Split Main Channel Percent of main channel that
is in split main channel
Length of main channel
that is in split main
channel (R2 calculated)
Total length of main
channel (thalweg, R2)
Braided Main Channel Percent of main channel that
is in braided main channel
Length of main channel
that is in braided main
channel (R2 calculated)
Total length of main
channel (thalweg, R2)
Side Channel Side channel length per river
mile
Total length of side
channels (HDR)
Total length of main
channel (thalweg, R2)
Upland Slough Upland slough length per
river mile
Total length of upland
slough habitat (HDR)
Total length of main
channel (thalweg, R2)
Side Slough Side slough length per river
mile
Total length of side
channel habitat (HDR)
Total length of main
channel (thalweg, R2)
Backwater density of backwaters
(#/mile) # backwaters (HDR) Total length of main
channel (thalweg, R2)
Tributary density of tributaries (#/mile) # tributaries (HDR) Total length of main
channel (thalweg, R2)
Tributary Mouth density of tributary mouths
(#/mile) # Tributary Mouths (HDR) Total length of main
channel (thalweg, R2)
Clear Water Plume density of plumes (#/mile) # plumes (HDR) Total length of main
channel (thalweg, R2)
Mesohabitat
Glide or Run Percent of main/side channel
habitat in glide/run
Total length of Glide or
Run (HDR)
Total Length of Main +
Side Channel Habitat
(HDR)
Riffle Percent of main/side channel
habitat in riffle
Total length of Riffle
(HDR)
Total Length of Main +
Side Channel Habitat
(HDR)
Beaver Complex Percent of slough habitat that
is beaver complex
Total length of Beaver
Complex Habitat (HDR)
Total length of slough
habitat (HDR)
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Table 3. Proportionality metrics for existing and alternate Focus Area options in comparison to total geomorphic reach
values in MR-2 and MR-7 based on 2012 habitat mapping (HDR 2013).
MR-2 MR-7
FA-171 FA-173 Total FA-115 LANE McKenzie Oxbow I Total
Proportion of Main Channel
that is Single Main Channel 100% 100% 95% 13% 6.8% 59% 34% 53%
Proportion of Main Channel
that is Split Main Channel 0% 0% 5.0% 87% 93% 41% 66% 47%
Side Channel Length/Main
Channel Length 0 0.56 0.22 0.23 0.76 0.46 0.45 0.36
Side Slough Length/Main
Channel Length 0.42 0.86 0.20 0 0.47 0.61 0.00 0.13
Upland Slough Length/Main
Channel Length 0 0.26 0.19 1.1 0 0.15 0.45 0.64
Backwaters per River Mile 0 0 0.067 1.5 0 0 0 0.20
Tributaries per River Mile 0.71 0.55 0.67 0.77 1.5 1.4 1.2 0.87
Tributary Mouths per River
Mile 0 0.55 0.80 0 1.5 0 1 0.20
Clear Water Plumes per River
Mile 0 0 0.33 0 0.77 0 0 0.067
Proportion of Slough Habitat
in Beaver Complex 0 0 0 42% 81% 0% 0% 16%
Proportion of Main Channel in
Glide/Run 100% 100% 97% 70% 89% 100% 82% 84%
Proportion of Main Channel in
Riffle 0% 0% 3.3% 30% 11% 0% 18% 16%
Notes:
1 Side Slough habitat entirely contained on island complex
2 Potential unmapped mouths/plumes
3 Unmapped beaver complex likely available
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Table 4. 1980s peak spawner counts. Source: ADF&G 1981, ADF&G 1983, Barrett et al. 1984, Barrett et al. 1985,
Thompson et al. 1986.
Chum Coho Pink
81 82 83 84 85 81 82 83 84 85 81 82 83 84 85
Little
Portage
31 0 18 4
8 0 0 2 140 7 162 7
Lower
McKenzie 14 0 1 23 0 0 133 18 24 50 56 23 28 585 3
Upper
McKenzie 0 0 0 0 1 0 0 0 0 0 0 17 0 11 2
Lane
Creek 76 5 6 31 1 3 5 2 24 13 291 0 28 1184 127
Gash
Creek 0 0 0 0 0 141 74 19 234 71 0 0 0 6 2
Slash
Creek 0 0 0 5 6 2 5 8 0 0 3 0
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority FERC Project No. 14241 Page 16 May 2013 Table 5. Locations, descriptions and selection rationale of 10 Final Focus Areas identified for detailed study in the Middle River Segment of the Susitna River. Focus Area identification numbers (e.g., Focus Area 184) represent the truncated Project River Mile (PRM) at the downstream end of each Focus Area. Focus Area ID Common Name Description Geomorphic Reach Location (PRM) Area Length (mi) Habitat Types Present Fish Use in 1980s Instream Flow Studies in 1980s Rationale for Selection Upstream Downstream Main Channel, Single Main Channel, Split Main Channel, Multiple Split Side Channel Side Slough Upland Slough Tributary Spawning Rearing IFG DIHAB RJHAB FA-184 Watana Dam Area approximately 1.4 miles downstream of dam site MR-1 185.7 184.7 1.0 X X N/A N/A N/A N/A N/A FA-184 length comprises 50% of MR-1 reach length (2 miles long) and contains split main channel and side channel habitat present in this reach. FA-173 Stephan Lake, Complex Channel Wide channel near Stephan Lake with complex of side channels MR-2 175.4 173.6 1.8 X X X X X N/A N/A N/A N/A N/A FA-173 contains a complex of main channel and off-channel habitats within wide floodplain. Represents greatest channel complexity within MR-2. Reach MR-2 is 15.5 miles long and channel is generally straight with few side channels and moderate floodplain width (2-3 main channel widths). FA-151 Portage Creek Single channel area at Portage Creek confluence MR-5 152.3 151.8 0.5 X X X X FA-151 is a single main channel and thus representative of the confined Reach MR-5. Portage Creek is a primary tributary of the Middle Segment and the confluence supports high fish use. FA-144 Side Channel 21 Side channel and side slough complex approximately 2.3 miles upstream Indian River MR-6 145.7 144.4 1.3 X X X X X X X X FA-144 contains a wide range of main channel and off-channel habitats, which are common features of Reach MR-6. Side Channel 21 is a primary salmon spawning area. Reach MR-6 is 26 miles long (30% of Middle Segment length) and is characterized by a wide floodplain and complex channel morphology with frequent channel splits and side channels. FA-141 Indian River Area covering Indian River and upstream channel complex MR-6 143.4 141.8 1.6 X X X X X X X X FA-141 includes the Indian River confluence and a range of main channel and off-channel habitats. High fish use of the Indian River mouth has been documented and DIHAB modeling was performed in main channel areas in the 1980s. Studies in the 1980s did not document high fish use of lateral habitats on the right bank upstream of the Indian River confluence. FA-138 Gold Creek Channel complex including Side Channel 11 and Slough 11 MR-6 140 138.5 1.5 X X X X X X X X The FA-138 primary feature is a complex of side channel, side slough and upland slough habitats, each of which support high adult and juvenile fish use. Complex channel structure of FA-138 is characteristic of Reach MR-6. IFG modeling was performed in side channel habitats in the 1980s. FA-128 Skull Creek Complex Channel complex including Slough 8A and Skull Creek side channel MR-6 129.7 128.1 1.6 X X X X X X X X X FA-128 consists of side channel, side slough and tributary confluence habitat features that are characteristic of the braided MR-6 reach. Side channel and side slough habitats support high juvenile and adult fish use and habitat modeling was completed in side channel and side slough habitats. FA-115 Lane Creek Area 0.6 miles downstream of Lane Creek, including Upland Slough 6A MR-7 116.5 115.3 1.2 X X X X X X X X FA-115 contains side channel and upland slough habitats that are representative of MR-7. Reach MR-7 is a narrow reach with few braided channel habitats. Upland Slough 6A is a primary habitat for juvenile fish and habitat modeling was done in side channel and upland slough areas. FA-113 Oxbow I Oxbow I Complex and Upstream Area MR-7 115.3 113.6 1.7 X X X X X X X FA-113 was added in response to Agency comments that important fish habitat area was underrepresented in MR-7. Oxbow I is an important chum salmon rearing area. FA-104 Whiskers Slough Whiskers Slough Complex MR-8 106 104.8 1.2 X X X X X X X X X X FA-104 contains diverse range of habitat, which is characteristic of the braided, unconfined Reach MR-8. FA-104 habitats support juvenile and adult fish use and a range of habitat modeling methods were used in side channel and side slough areas.
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Table 6. Lengths of final Focus Areas as proportion of each Geomorphic Reach.
Geomorphic
Reach
Geomorphic Reach Current Focus Area Revised Focus
Area Length as
% of Geomorphic
Reach Start End Length ID Start End Length
MR-1 187.1 184.6 2.5 184 185.7 184.7 1 40%
MR-2 184.6 169.6 15 173 175.4 173.6 1.8 12%
MR-5 153.9 148.4 5.5 151 152.3 151.8 0.5 9.1%
MR-6 148.4 122.7 25.7
144 145.7 144.4 1.3
23% 141 143.4 141.8 1.6
138 140 138.5 1.5
128 129.7 128.1 1.6
MR-7 122.7 107.8 14.9 115 116.5 115.3 1.2 19% 113 115.3 113.6 1.7
MR-8 107.8 102.4 5.4 104 106 104.8 1.2 22%
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8. FIGURES
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority FERC Project No. 14241 Page 19 May 2013 Figure 1. Map of the Middle Segment of the Susitna River depicting the eight Geomorphic Reaches and original locations of and potential changes to Focus Areas. No Focus Areas have been proposed in MR-3 and MR-4 due to safety issues related to sampling within or proximal to Devils Canyon.
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority FERC Project No. 14241 Page 20 May 2013 Figure 2. Map showing habitat mapping for geomorphic reach MR-2 (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority FERC Project No. 14241 Page 21 May 2013 Figure 3. Map showing Focus Area 115 beginning at Project River Mile 115.3 and extending upstream to PRM 116.5. This Focus Area is located about 0.6 miles downstream of Lane Creek and consists of side channel and upland slough habitats including Slough 6A.
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority FERC Project No. 14241 Page 22 May 2013 Figure 4. Map of geomorphic reach MR-7 highlighting side sloughs and tributary features not captured by existing FA-115.
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority FERC Project No. 14241 Page 23 May 2013 Figure 5. Map showing habitats mapped in the Lane Creek area.
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority FERC Project No. 14241 Page 24 May 2013 Figure 6. Map showing habitats mapped in the McKenzie Creek area.
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority FERC Project No. 14241 Page 25 May 2013 Figure 7. Map showing habitats mapped in the Oxbow I area.
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9. APPENDIX 1. IFSTT MEETING NOTES, APRIL 26, 2013
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Meeting Notes
Instream Flow Study Technical Team (IFSTT)
Conference Call
April 26, 2013
LOCATION: Teleconference
TIME: 9:00 am to 1:00 pm (AKDT)
SUBJECT: Middle River Focus Areas and Lower River IFS Modeling
GOAL: To discuss adjustments to Middle River Focus Areas, review Lower River IFS
modeling approach and identify topics for next IFS technical team meeting
PARTICIPANTS: Alice Shelly (R2), Becky Long (Coalition for Susitna Dam Alternatives),
Betsy McGregor (AEA), Bill Fullerton (TT), Bill Miller (MEC), Catherine
Berg (USFWS), Chris Holmquist-Johnson (USGS), Dana Schmidt (GAI),
Dudley Reiser (R2), Eric Rothwell (NMFS), Greg Auble (USGS), Jeff
Davis (ARRI), Joe Klein (ADF&G), Kasey Clipperton (GAI), Kate Knox
(R2), Kim Sager (DNR), Laura Arendall (R2), Leanne Hanson (USGS),
Leslie Jensen (ARRI), Lyle Zevenbergen (TT), MaryLou Keefe (R2),
Michael Barclay (HDR), Michael Lilly (GWS), Mike Buntjer (USFWS),
Phil Hilgert (R2), Sandie Hayes (AEA), Steve Padula (McMillen), Sue
Walker (NMFS)
This was the first of what will be several meetings of the Instream Flow Study Technical Team
(IFSTT), that are designed to allow more detailed discussion of technical topics than could
otherwise be achieved during normal Technical Work Group meetings. The IFSTT meetings are
intended to vet, discuss and, where possible, reach agreement on technical issues and questions
regarding the implementation of various elements of the IFS for the Susitna-Watana
Hydroelectric Project. This first meeting was focused primarily on two issues – potential
adjustments to Middle River Focus Areas, and a discussion of the Lower River Instream Flow
sampling approach (see Meeting Agenda below). Some discussion also occurred early on in the
meeting regarding the habitat classification scheme and potential differences of opinion
concerning the interpretation of specific habitat types that were used in the habitat mapping
exercise. A summary of the discussion related to each of these topics is presented below.
MAJOR TOPICS AND DISCUSSION POINTS
Reviewed general concerns of USFWS/NMFS about elements of the habitat classification
system that will be used on the Project. This included a discussion of McKenzie Creek island
“side slough” habitat types that might instead be designated as “cross-over channels.” It was
noted that the need for any modifications to the specific habitat types would be realized as part
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of the more detailed habitat mapping that would occur in 2013 field studies. Adjustments
could then be made. As a preliminary step, it was agreed that the habitat types of each FA be
delineated and provided to agencies for review, with the objective of identifying any habitat
type “calls” that they consider questionable. These will be noted and briefly discussed during
the next IFSTT meeting, and further evaluated as part of the field studies.
Discussed portions of the Susitna River near Lane Creek, McKenzie Creek, and Oxbow 1 as
potential Focus Areas that could be studied in MR- 7, instead of FA-171 located in MR-2.
This was a follow-up to the FERC determination of February 1, 2013 (page B-92) indicating a
move of Focus Area from MR-2 to MR-7 should be discussed with agencies. This was the
major topic discussed during the meeting and included reviews of each potential candidate site
(i.e., pros and cons including railroad restrictions). The Thermal Infrared Imagery (TIR)
completed by Watershed Sciences was reviewed for each of the candidate sites noting areas of
apparent groundwater influence; meeting attendees generally acknowledged the value of the
TIR. The discussion resulted in agreement of the selection of a new FA located near Oxbow 1
(FA-113), and dropping FA-171.
Discussed Lower River modeling approach, noting that the complexity of the habitats will
require development of a series of individual habitat specific models that can be used for
evaluating habitat-flow relationships within areas considered biologically important to fish.
Question was raised regarding selection criteria for the tributaries proposed for study in 2013.
It was noted the tributaries were selected based on studying a subset of those considered
biologically important to fish based in part on 1980s studies as well as current information.
Additional tributaries may be studied in 2014 based on results in 2013.
Response to the FERC determination concerning the fish barrier studies was discussed and it
was noted that the revised plan would be delivered on May15; and will follow with a 15-day
comment period; the technical memorandum for this is due on June 30.
Topics for the next IFSTT were discussed with emphasis placed on a series of potential topics
related to HSC and HSI data collection.
DECISIONS REACHED
Agencies and AEA were in agreement that FA-171 (located in MR-2) will be dropped leaving
a single FA (FA-173) in MR-2 for investigation.
Agencies and AEA were in agreement that a new FA would be located in MR-7 (FA-113), and
that it would be located in a reach of the Susitna River that includes the Oxbow 1 area
(including unnamed tributary PRM 113.7 and Slash and Gash Creeks). This area is
immediately adjacent to FA-115, so the hydraulic modeling will encompass both areas
together. However, the two Focus Areas will be considered separately for reporting purposes.
The lower boundary of the area will be below the unnamed tributary (~PRM 113.6) and the
upper boundary at ~PRM 115.3.
Agencies and AEA were in agreement that the IFS work in the Lower River Reach should
proceed as described during the meeting; some further discussion of tributaries is needed
relative to 2014 studies but will depend on results of 2013 studies.
Topics for the next IFSTT meeting were reviewed, and it was agreed that the primary focus
would be to discuss target species and HSC/HSI data collection techniques; HSC/HSI topics of
stranding/trapping modeling, varial zone modeling, effective spawning were considered lower
priority topics at this time.
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ACTION ITEMS
The following ACTION ITEMS were identified:
ction Items Date Responsibility
1) Update Post FERC SPD Recommendations Tech Memo and
file with FERC by 5/31/13. Include a map of each FA
depicting the habitat types and an updated table from the
RSP indicating the proportion of each reach included within
the FAs. Provide the maps if available sooner than the
technical memorandum.
05/31/13 R2
2) Post a map of each Focus Area (including new FA-113)
showing the preliminary habitat types identified by HDR.
As soon
as
available
R2
3) Develop meeting agenda and meeting materials for the next
meeting scheduled to occur 5/17/13, to cover the following
topics:
▫ Target Species and Life stages
▫ HSC – 2013 sampling effort, target locations,
microhabitat data to be collected
▫ Habitat Classification System – provide clarified set
of definitions from RSP and approach for moving
forward without changing the classification system
05/13 R2
4) Discuss 2-D/1-D modeling (development of digital terrain
model, transect selection, calibration flows, data aggregation,
etc.) off-line with Joe Klein-ADF&G.
05/13 R2 and
ADF&G
5) As field schedules become established, coordinate with
agencies to allow them to participate on an opportunist basis.
As soon
as
available
R2
6) Develop summary of April 26, 2013 conference call and
identify decisions and action items.
05/13 R2
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 May 2013
10. APPENDIX 2. FOCUS AREA MAPS WITH PRELIMINARY
MACROHABITAT CLASSIFICATION TYPES
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 34 May 2013 Figure 2-1. Map showing boundaries of FA-184 in Geomorphic Reach MR-1, along with associated mapped macrohabitat units (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 35 May 2013 Figure 2-2. Map showing boundaries of FA-173 in Geomorphic Reach MR-2, along with associated mapped macrohabitat units (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 36 May 2013 Figure 2-3. Map showing boundaries of FA-151 in Geomorphic Reach MR-5, along with associated mapped macrohabitat units (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 37 May 2013 Figure 2-4. Map showing boundaries of FA-144 in Geomorphic Reach MR-6, along with associated mapped macrohabitat units (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 38 May 2013 Figure 2-5. Map showing boundaries of FA-141 in Geomorphic Reach MR-6, along with associated mapped macrohabitat units (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 39 May 2013 Figure 2-6. Map showing boundaries of FA-138 in Geomorphic Reach MR-6, along with associated mapped macrohabitat units (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 40 May 2013 Figure 2-7. Map showing boundaries of FA-128 in Geomorphic Reach MR-6, along with associated mapped macrohabitat units (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 41 May 2013 Figure 2-8. Map showing boundaries of FA-115 in Geomorphic Reach MR-7, along with associated mapped macrohabitat units (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 42 May 2013 Figure 2-9. Map showing boundaries of FA-113 in Geomorphic Reach MR-7, along with associated mapped macrohabitat units (HDR 2013).
ADJUSTMENTS TO MIDDLE RIVER FOCUS AREAS Susitna-Watana Hydroelectric Project Alaska Energy Authority 1. FERC Project No. 14241 Page 43 May 2013 Figure 2-10. Map showing boundaries of FA-104 in Geomorphic Reach MR-8, along with associated mapped macrohabitat units (HDR 2013).