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Susitna‐Watana Hydroelectric Project Document
ARLIS Uniform Cover Page
Title:
Riparian vegetation study downstream of the proposed Susitna-Watana
Dam, Study plan Section 11.6, 2014-2015 Study Implementation Report SuWa 289
Author(s) – Personal:
Author(s) – Corporate:
ABR, Inc.-Environmental Research & Services
AEA‐identified category, if specified:
November 2015; Study Completion and 2014/2015 Implementation Reports
AEA‐identified series, if specified:
Series (ARLIS‐assigned report number):
Susitna-Watana Hydroelectric Project document number 289
Existing numbers on document:
Published by:
[Anchorage : Alaska Energy Authority, 2015]
Date published:
October 2015
Published for:
Alaska Energy Authority
Date or date range of report:
Volume and/or Part numbers:
Study plan Section 11.6
Final or Draft status, as indicated:
Document type:
Pagination:
ii, 12 pages
Related works(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/
Susitna-Watana Hydroelectric Project
(FERC No. 14241)
Riparian Vegetation Study Downstream of the
Proposed Susitna-Watana Dam
Study Plan Section 11.6
2014–2015 Study Implementation Report
Prepared for
Alaska Energy Authority
Prepared by
ABR, Inc.—Environmental Research & Services
October 2015
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page i October 2015
TABLE OF CONTENTS
1. Introduction ....................................................................................................................... 1
2. Study Objectives................................................................................................................ 1
3. Study Area ......................................................................................................................... 2
4. Methods and Variances in 2014 ....................................................................................... 3
4.1. Develop Mapping Materials from Historical and Current Data ............................. 4
4.1.1. Variances ......................................................................................... 4
4.2. Field Surveys .......................................................................................................... 4
4.2.1. Plot Allocation Procedures ............................................................. 4
4.2.2. Floodplain Sediment Stratigraphy Study ........................................ 4
4.2.3. Surface Elevation ............................................................................ 5
4.2.4. Sampling of ITU Mapping Plots ..................................................... 5
4.2.5. Sampling of ELS Plots .................................................................... 5
4.3. ITU Classification and Mapping of Downstream Riparian Areas .......................... 5
4.3.1. ITU Classification ........................................................................... 5
4.3.2. ITU Mapping .................................................................................. 5
5. Results ................................................................................................................................ 6
6. Discussion........................................................................................................................... 6
7. Conclusion ......................................................................................................................... 7
7.1. Decision Points from Study Plan ............................................................................ 7
7.2. Modifications to the Study Plan .............................................................................. 7
8. Literature Cited ................................................................................................................ 8
9. Tables ................................................................................................................................. 9
10. Figures .............................................................................................................................. 10
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page ii October 2015
LIST OF TABLES
Table 5.1-1. Server Location and File/Folder Names for the Riverine Vegetation Study Field Data
Collected in 2012–2014. ................................................................................................................. 9
LIST OF FIGURES
Figure 3-1. Study Area for the Riparian Vegetation Study, Susitna-Watana Hydroelectric
Project, 2014. .........................................................................................................................11
Figure 4.2-1. Sediment Core Sampling Locations, Riparian Vegetation Study, Susitna-
Watana Hydroelectric Project, 2014. .....................................................................................12
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page iii October 2015
LIST OF ACRONYMS, ABBREVIATIONS, AND DEFINITIONS
Abbreviation Definition
ABR ABR, Inc.—Environmental Research & Services
AEA Alaska Energy Authority
ELS Ecological Land Survey
FA Focus Area
FERC Federal Energy Regulatory Commission
IFS Instream Flow Study
ISR Initial Study Report
ITU Integrated Terrain Unit
PM&E protection, mitigation, and enhancement
PRM Project River Mile
Project Susitna-Watana Hydroelectric Project No. 14241
Q1, Q2, Q3, Q4 first quarter, second quarter, third quarter, and fourth quarter of the annual year
R2 R2 Resource Consultants, Inc.
Riparian IFS Riparian Instream Flow Study
RSP Revised Study Plan
SIR Study Implementation Report
SPD study plan determination
TWG Technical Workgroup
UK United Kingdom
USR Updated Study Report
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 1 October 2015
1. INTRODUCTION
This Riparian Vegetation Study Downstream of the Proposed Susitna-Watana Dam (Riparian
Vegetation Study), Section 11.6 of the Revised Study Plan (RSP) approved by the Federal Energy
Regulatory Commission (FERC) for the Susitna-Watana Hydroelectric Project, FERC Project No.
14241, focuses on characterizing and mapping local-scale riparian ecosystems on the Susitna River
downstream of the Project dam site and developing models to describe the natural successional
pathways for riparian vegetation along the Susitna River. This baseline information will be used
to support the development of a spatially-explicit model to predict potential changes in riparian
vegetation due to Project effects; the model will be developed in the Riparian Instream Flow Study
(Riparian IFS) as described in the Study Implementation Report (SIR) for Study 8.6.
A summary of the development of this study, together with the Alaska Energy Authority’s (AEA)
implementation of it through the 2013 study season, appears in Part A, Section 1 of the Initial
Study Report (ISR) filed with FERC in June 2014. As required under FERC’s regulations for the
Integrated Licensing Process, the ISR describes AEA’s “overall progress in implementing the
study plan and schedule and the data collected, including an explanation of any variance from the
study plan and schedule.” (18 CFR 5.15(c)(1)).
Since filing the ISR in June 2014, AEA has continued to implement the FERC-approved plan for
the Riparian Vegetation Study. For example:
From September 23 to September 28, 2014, ABR and R2 conducted field work to collect
sediment cores for the floodplain sediment stratigraphy component of the Riparian
Vegetation Study.
On October 17, 2014, AEA held an ISR meeting for the Riparian Vegetation Study.
On November 14, 2014, R2 and ABR posted the Riparian Vegetation Groundwater /
Surface Water Study Sampling Design Technical Memorandum (R2 and ABR 2014) to the
Project SharePoint site (this document is now Appendix A in the SIR for Study 8.6).
Integrated Terrain Unit (ITU) mapping of riparian ecosystem components in the study area
for the Riparian Vegetation Study was continued in 2014 and 2015.
In furtherance of the next round of ISR meetings and FERC’s Study Plan Determination (SPD)
expected in 2016, this report describes AEA’s overall progress in implementing the Riparian
Vegetation Study in 2014 and 2015. Rather than a comprehensive reporting of all field work, data
collection, and data analysis since the beginning of AEA’s study program, this report is intended
to supplement and update the information presented in Part A of the ISR for the Riparian
Vegetation Study through June 2015. It describes the methods and results of the 2014 and 2015
efforts, and includes a discussion of the results achieved.
2. STUDY OBJECTIVES
As established in the Study Plan, the overall goals of the Riparian Vegetation Study are to prepare
maps of existing, local-scale riparian ecosystems (riparian ecotypes), wetlands, and wildlife habitat
types in areas downstream from the proposed Project dam site; characterize sedimentation,
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 2 October 2015
vegetation succession, and vegetation-soil-landscape relationships; and coordinate with the
Riparian IFS (Study 8.6) and other closely related studies to provide complimentary data products
to support the development of a spatially-explicit model to predict potential changes to
downstream riparian floodplain vegetation due to Project modifications of flow, sedimentation,
groundwater, and ice processes (to be developed in the Riparian IFS; see Study 8.6). This multi-
year study was initiated in 2012. Substantial work on the study occurred in 2013 (see ISR Study
11.6) and 2014 (this report). The mapping prepared in this study will be used in the FERC License
Application to assess the impacts to riparian ecotypes, wetlands, and wildlife habitats (see Study
10.19) in areas downstream from the Project dam site, and to develop possible protection,
mitigation, and enhancement (PM&E) measures to address any identified effects.
The specific objectives of the Riparian Vegetation Study are to:
Classify, delineate, and map riparian ecotypes, wetlands, and wildlife habitats downstream
from the Watana Dam site;
Characterize the role of erosion and sediment deposition in the formation of floodplain
surfaces, soils, and vegetation using a combination of soil stratigraphic descriptions, sieve
analysis, and several complimentary sediment dating techniques;
Quantify and describe Susitna River riparian vegetation communities using a combination
of basic statistical summaries (e.g., basal area, density, stand age) and multivariate
statistical techniques (e.g., cluster analysis, ordination, sorted tables), which will be used
to develop of a series of conceptual models of floodplain vegetation succession building
from those developed by Helm and Collins (1997); and
Coordinate closely in the implementation of the Riparian IFS (Study 8.6), Groundwater
Study (Study 7.5), Ice Processes in the Susitna River Study (Study 7.6), and Fluvial
Geomorphology Modeling below Watana Dam Study (Study 6.6) to provide necessary and
complimentary data, including vegetation successional models and mapping in support of
a spatially-explicit model (to be developed in the Riparian IFS; see Study 8.6) to predict
potential impacts to downstream riparian floodplain vegetation due to Project alterations
of existing conditions downstream of the Project dam site.
3. STUDY AREA
As established in the Study Plan, the Riparian Vegetation Study is being conducted in riparian
areas along the Susitna River below the proposed Project dam site, with the downstream and lateral
extents as described below.
The 2013–2014 study area for the Riparian Vegetation Study is illustrated in Figure 3-1; this same
study area is being used for the Riparian IFS (Study 8.6), Fluvial Geomorphology Modeling below
Watana Dam Study (Study 6.6), and the Groundwater Study (Study 7.5). The study area includes
those riparian areas downstream of the Project dam site to a point at which the effects of altered
stage and flow effects expected in the Susitna River would not be ecologically significant (i.e., the
expected hydraulic alterations would be overridden by the input from other rivers and/or the effects
of tidal fluctuations from Cook Inlet). In RSP Section 11.6, the longitudinal extent of the Riparian
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
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FERC Project No. 14241 Page 3 October 2015
Vegetation Study area extended to project river mile (PRM) 75 because existing information at the
time the RSP was prepared (2012) indicated that the hydraulic effects of the Project below the
Three Rivers Confluence at the Sunshine Gage (PRM 84) showed substantial attenuation, although
small hydraulic effects appeared to be detectable as far downstream as the Susitna Station Gage
(PRM 26). The final determination of how far downstream Project operational effects would
extend was made in Q1 2013 following the completion of the Open-water Flow Routing Model
(see ISR Study 8.5). At that time, a Technical Working Group (TWG) meeting was held to discuss
the selection of Focus Areas (FAs) and study sites, which included discussion of the downstream
extent of the study area for the riparian studies. During the TWG meeting, it was agreed that the
downstream extent of the study areas for the riparian studies, including the Riparian Vegetation
Study, would extend to Project River Mile (PRM) 29.5, as described in the Technical
Memorandum: Selection of Focus Areas and Study Sites in the Middle and Lower Susitna River
for Instream Flow and Joint Research Studies – 2013 and 2014 (March 1, 2013) (R2 2013).
For the 2013 and 2014 work, the lateral extent of the Riparian Vegetation Study area was defined
by the extent of the riverine physiographic region generated by the Susitna River. Riverine
physiography includes (1) those areas of the valley bottom, including off-channel water bodies,
that are directly influenced by regular (0–25 year) to irregular (25–100 year) overbank flooding;
and (2) those areas of the valley bottom influenced indirectly by groundwater associated with the
Susitna River. In 2012, riverine physiography was mapped by the Riparian Vegetation Study team
from the Project dam site to PRM 29.5 (Figure 3-1) by interpretation of image-signatures on high-
resolution aerial imagery for the Susitna River. The riverine physiographic map has undergone
review and refinement by the principal investigators leading the Riparian Vegetation Study, the
Riparian IFS (Study 8.6), and associated physical-processes studies (groundwater [Study 7.5], ice
processes [Study 7.6], and fluvial geomorphology [Study 6.6]).
4. METHODS AND VARIANCES IN 2014
This study involves the use of Integrated Terrain Unit (ITU) mapping, which is an integrated
approach to mapping landscape elements. ITU mapping is a multivariate mapping process in which
terrain unit map boundaries are adjusted by on-screen digitizing over high-resolution aerial
photography or satellite imagery so that there is increased coincidence between the boundaries and
occurrences of interdependent ITU variables, such as hydrography, geology, physiography, soils,
and vegetation units (Jorgenson et al. 2003; 2009). The ITU approach being used to map riparian
ecotypes, wetlands, and wildlife habitats is based on methods and concepts developed for
Ecological Land Survey (ELS) studies conducted in tundra, boreal forest, and coastal regions in
Alaska over the past 15 years (see Jorgenson et al. 2003 for an example study in Southcentral
Alaska). The ITU mapping approach for the Riparian Vegetation Study involves mapping terrain
units such as vegetation type, balsam poplar size class (e.g., pole, timber, large timber), fluvial
geomorphology, and surface-form types. These map data are being combined into units with
ecological importance (in this case riparian ecotypes, wetlands, and wildlife habitats). Also based
on previous ELS studies in Alaska, a set of field plots are being sampled to collect detailed data
on site characteristics, environmental variables, successional vegetation, and soils; a subset of the
field plots also are designed for use as permanent, long-term monitoring plots (see ISR Study 11.6,
Part A, Section 4.2.5).
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
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FERC Project No. 14241 Page 4 October 2015
For this study, a series of maps will be produced, including maps of the individual terrain units
(i.e., geomorphology, surface form, vegetation type, poplar size class), and maps of the aggregated
terrain units (i.e., riparian ecotype, wetlands, and wildlife habitat). The mapping of wildlife
habitats in the Riparian Vegetation Study is being conducted in coordination with the Vegetation
and Wildlife Habitat Mapping Study in the Upper and Middle Susitna Basin (Study 11.5) to derive
a seamless map of wildlife habitats that apply Project-wide. Similarly, the mapping of wetlands is
being conducted in coordination with the Wetland Mapping Study in the Upper and Middle Susitna
Basin (Study 11.7) so that wetlands in the Riparian Vegetation Study area can be similarly
classified; this process will result in a single Project-wide wetland map.
4.1. Develop Mapping Materials from Historical and Current Data
The methods for developing mapping materials, as described in the Study Plan, were previously
implemented in 2013 with no variances (see ISR Study 11.6, Part A, Section 4.1).
4.1.1. Variances
In 2014, there were no variances from the protocols described in the Study Plan to develop
mapping materials from historical and current data.
4.2. Field Surveys
Only limited field surveys for the collection of soil cores for sediment aging analyses were
conducted in 2014 (see Sections 4.2.2 and 4.2.4 below). The methods for the field surveys in 2014
were implemented as described in the Study Plan and in more detail in the ISR (Study 11.6, Part
A, Sections 4.2.2 and 4.2.4) with no variances.
4.2.1. Plot Allocation Procedures
4.2.1.1. ELS Plots
No ELS plots were sampled in 2014 and therefore no plot allocation procedures were used.
4.2.1.2. ITU Mapping Plots
Vegetation data for 18 new ITU mapping plots were collected in 2014 in association with the soil
core collection work (see Section 4.2.4 below).
4.2.1.3. Variances
No variances from the plot-allocation procedures described in the Study Plan and modified in the
ISR (Study 11.6, Part A, Section 4.2.1) occurred in 2014.
4.2.2. Floodplain Sediment Stratigraphy Study
In 2014, the field methods for the floodplain sediment stratigraphy study were implemented as
described in the Study Plan and in more detail in the ISR (Study 11.6, Part A, Section 4.2.2) with
no variances. Field work was conducted from September 23–30 to collect soil cores for sediment
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 5 October 2015
aging and stratigraphic analysis. Twenty-five soil stratigraphy cores were sampled in riparian areas
of the Susitna River between PRM 105 and 146 (Figure 4.2-1). Seven of the 25 sediment
stratigraphy plots were co-located with previously sampled ELS plots as described in the ISR
(Study 11.6, Part A, Section 4.2.1.1). The other 18 sediment stratigraphy plots were sampled in
conjunction with ITU mapping plots (see Section 4.2.4 below).
4.2.2.1. Variances
There were no variances from the methods described in the Study Plan and the ISR (Study 11.6,
Part A, Section 4.2.2) for the floodplain sediment stratigraphy study.
4.2.3. Surface Elevation
In 2014, no surface elevation data were collected.
4.2.4. Sampling of ITU Mapping Plots
In 2014, 18 new ITU mapping plots were sampled in association with the soil core collection work
described above in Section 4.2.2. Because the soil core collection work took place late in the
growing season (September), only vegetation structure, plant community composition, and percent
cover data for the dominant plant species were recorded at each ITU mapping plot. This does not
constitute a variance in the methods for the sampling of ITU mapping plots as described in the
Study Plan. Rather, in this case the field team simply acquired additional data on the vegetation
present at each soil core collection site.
4.2.4.1. Variances
In 2014, there were no variances from the sampling methods for ITU mapping plots as described
in the Study Plan.
4.2.5. Sampling of ELS Plots
No ELS plots were sampled in 2014.
4.3. ITU Classification and Mapping of Downstream Riparian Areas
4.3.1. ITU Classification
In 2014, no additional ITU classification work occurred beyond what was reported in the ISR
(Study 11.6, Part A, Section 4.3.1). The final classification of riparian ecotypes, wetlands, and
wildlife habitats in riparian areas downstream of the proposed Watana Dam will be conducted after
completion and finalization of the ITU mapping.
4.3.2. ITU Mapping
In 2014, the study team continued the ITU mapping work in the study area, and this work has
continued in 2015 as well. The methods for ITU mapping in 2014 and 2015 were implemented as
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 6 October 2015
described in the Study Plan with no variances. Current and high-resolution imagery is available to
support the ITU mapping work throughout the full study area.
4.3.2.1. Variances
In 2014, there were no variances from the procedures described in the Study Plan for ITU
classification and ITU mapping.
5. RESULTS
The cumulative, error-corrected field data collected for this study in 2012, 2013, and 2014 are
available at:
http://gis.suhydro.org/SIR/11-Botanical/11.6-Riparian/
See Table 5.1-1 for details.
There were no additional ELS plots sampled in 2014. In September 2014, 18 ITU mapping plots
were sampled and 25 sediment cores were collected and described (Figure 4.2-1). The 25 sediment
core sampling sites were co-located with 18 ITU mapping and 7 ELS plots. The 7 ELS plots were
previously sampled in 2013 for vegetation composition and general soils data (Figure 3-1). The 18
new ITU plots were added in 2014 to provide vegetation data for the 18 additional sites at which
sediment cores were sampled.
The 25 sediment cores have been sent to the Department of Geography, University of Exeter, in
the UK for 210Pb and 137Cs analyses. Laboratory analyses have not been completed. Sediment
isotope laboratory results from the 2014 soil cores will be used to quantify floodplain sediment
deposition over the last century.
In 2014 and 2015, substantial progress was made towards completing the ITU mapping for this
study. As of June 30, 2015, draft ITU map polygons had been completed for 98 percent of the
study area.
6. DISCUSSION
The field data collection efforts and the mapping prepared in 2014 were conducted as planned and
described in the Study Plan. Substantial progress has been made in completing the ITU mapping
in the Upper, Middle, and Lower River portions of the study area. Additional ITU field data are
needed to proof and QC the mapping in the Upper River portion of the study area. The progress of
the study to date is sufficient to meet the study objectives with an additional year of field data
collection, ITU mapping, and the classification of ecotypes, wetlands, and wildlife habitat types
for riparian areas of the Susitna River. When the mapping of riparian ecotypes is complete, the
modeling of natural successional pathways for riparian vegetation in the Susitna River floodplain
downstream of the proposed Watana Dam, and the collaboration with researchers for the Riparian
IFS (Study 8.6) on the modeling of post-development riparian vegetation change, will be
conducted.
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
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FERC Project No. 14241 Page 7 October 2015
7. CONCLUSION
In combination, the ITU mapping work and the final field surveys to be completed; the derivation
of riparian ecotypes, wildlife habitats, and wetland types; the modeling of natural riparian
vegetation successional pathways; and the modeling of riparian change in collaboration with the
Riparian IFS (Study 8.6) will be adequate to meet the Study Plan objectives. Substantial progress
was made in 2014 and early 2015 in mapping ITU variables (the study area is 98 percent mapped).
As described above, once the field work and ITU mapping are completed, the final elements of the
study will be performed and reported in the Updated Study Report.
7.1. Decision Points from Study Plan
There were no decision points in the FERC-approved Study Plan to be evaluated for this study
following the completion of 2014 work.
7.2. Modifications to the Study Plan
After preparation of the ISR for this study in June 2014, one modification was developed for
implementation during completion of this study:
In response to agency comments during the October 17, 2014 ISR meeting concerning the Project
riparian studies, the Riparian IFS and Riparian Vegetation Study teams prepared a revised design
for the co-located sampling of groundwater/surface water and riparian vegetation (see the Riparian
Vegetation Groundwater / Surface Water Study Sampling Design Technical Memorandum [R2 and
ABR 2014; now Appendix A in the SIR for Study 8.6] for more details). The revised design calls
for the additional sampling of rapid vegetation transects (RVTs) to be established in four FAs in
the Middle River and along four riparian transects in the Lower River at which there are
groundwater/surface water (GW/SW) transects and groundwater wells. In addition to co-located
ELS plots and groundwater wells (RSP Section 11.6.4.2.4), to collect vegetation data along the
full length of GW/SW transects, a minimum of five RVTs will be sampled in each mapped riparian
ecotype along each GW/SW transect. The RVTs will be evenly distributed along elevation
gradients within each ecotype, as determined by a digital elevation model derived from Light
Detection and Ranging (LiDAR) data for the GW/SW transects. Sampling along RVTs will
involve the same point-intercept sampling procedures used on ELS plots (see ISR Study 11.6, Part
A, Section 4.2.5) but the RVTs will be smaller in size (25 m [82 ft] in length) and will be oriented
perpendicular to each GW/SW transect. The additional data from the RVTs will be combined with
those from the ELS plots to model plant frequency response curves along GW/SW gradients as
described by Henszey et al. (2004). This modification will assist in achieving the study objectives
by increasing the confidence in characterizing the relationship between GW/SW gradients and
plant community composition in the study area (to be developed in Study 8.6). The modification
also will provide more data for use in modeling the predicted changes in riparian vegetation due
to alterations in GW/SW gradients as a result of Project development.
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
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FERC Project No. 14241 Page 8 October 2015
8. LITERATURE CITED
Helm, D. J., and W. B. Collins. 1997. Vegetation succession and disturbance on a boreal forest
floodplain, Susitna River, Alaska. Canadian Field-Naturalist 111:553–566.
Henszey, R. J., K. Pfeiffer, and J. R. Keough. 2004. Linking surface and ground-water levels to
riparian grassland species along the Platte River in Central Nebraska, USA. Wetlands 24:
665-687.
Jorgenson, M. T., J. E. Roth, S. F. Schlentner, E. R. Pullman, M. J, Macander, and C. H. Racine.
2003. An ecological land survey for Fort Richardson, Alaska. Technical Report
Development Center, Cold Regions Research and Engineering Laboratory, Hanover, New
Hampshire.100 pp.
Jorgenson, M. J., J. E. Roth, P. F. Miller, M. J. Macander, M. S. Duffy, A. F. Wells, G. V. Frost,
and E. R. Pullman. 2009. An ecological land survey and landcover map of the Arctic
Network. Natural Resource Report NPS/ARCN/NRTR—2009/270. National Park Service,
Fort Collins, Colorado. 307 pp.
R2 (R2 Resource Consultants, Inc.). 2013. Technical Memorandum: Selection of Focus Areas and
Study Sites in the Middle and Lower Susitna River for Instream Flow and Joint Research
Studies – 2013 and 2014. March 1, 2013. Prepared for the Alaska Energy Authority by R2
Resource Consultants, Inc., Anchorage, Alaska.
R2 and ABR (R2 Resource Consultants, Inc., and ABR, Inc.—Environmental Research &
Services). 2014. Riparian Vegetation Groundwater / Surface Water Study Sampling Design
Technical Memorandum. November 14, 2014. Prepared for the Alaska Energy Authority
by R2 Resource Consultants, Inc., and ABR, Inc.—Environmental Research & Services,
Anchorage and Fairbanks, Alaska.
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PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
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FERC Project No. 14241 Page 9 October 2015
9. TABLES
Table 5.1-1. Server Location and File/Folder Names for the Riverine Vegetation Study Field Data Collected in 2012–2014.
Server Pathway or File/Folder Name Description
http://gis.suhydro.org/SIR/11-
Botanical/11.6-Riparian/ Pathway to data files.
11_6_RIPR_Cumulative_Data_ABR.zip
Zip file containing ELS plot, ITU mapping plot, and soils data in a Microsoft
Access database, and a geodatabase of GIS data layers for the Riverine
Vegetation Study.
Photos (folder)
Field (JPEG) photos organized in subfolders as follows: ELS and ITU mapping
plot photos in 2012 (12-174.3_ELS_plots) and 2013 (13-174.3_ELS_plots),
intensive ELS plot photos in 2013 (13-174.3_Intensive_plots), soil profile photos
in 2013 (FA104_TR 1_soil_profile and FA104_TR 2_soil_profile), and sediment
core sampling photos in 2013 and 2014 (renamed_sediment_core_photos). Each
photo is labeled with the sample plot number (see the Access database which
links to each photo).
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
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FERC Project No. 14241 Page 10 October 2015
10. FIGURES
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE
PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 11 October 2015
Figure 3-1. Study Area for the Riparian Vegetation Study, Susitna-Watana Hydroelectric Project, 2014.
STUDY IMPLEMENTATION REPORT RIPARIAN VEGETATION STUDY DOWNSTREAM OF THE PROPOSED SUSITNA-WATANA DAM (STUDY 11.6)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 12 October 2015
Figure 4.2-1. Sediment Core Sampling Locations, Riparian Vegetation Study, Susitna-Watana Hydroelectric Project, 2014.