Yadkin Project (FERC No. 2197)
Reservoir Fish and Aquatic Habitat Assessment
Final Study Plan
Alcoa Power Generating Inc. (APGI) is the licensee for the
Yadkin Hydroelectric Project. The
Yadkin Project is currently licensed by the Federal Energy Regulatory Commission
(FERC) as Project No. 2197. This
license expires in 2008 and APGI must file a new license application with FERC
on or before
April 30, 2006
to continue operation of the Project.
The Yadkin Project consists of four reservoirs, dams, and
powerhouses (High Rock, Tuckertown,
, and Falls) located on a 38-mile stretch of the
. The Project generates electricity
to support the power needs of Alcoa’s Badin Works, to support its other
aluminum operations, or is sold on the open market.
As part of the relicensing process, APGI prepared and
distributed, in September 2002, an Initial Consultation Document (ICD), which
provides a general overview of the Project.
Agencies, municipalities, non-governmental organizations and members of
the public were given an opportunity to review the ICD and identify information
and studies that are needed to address relicensing issues.
To further assist in the identification of issues and data/study needs,
APGI has formed several Issue Advisory Groups (IAGs) to advise APGI on resource
issues throughout the relicensing process. IAGs
will also have the opportunity to review and comment on Draft Study Plans.
This Draft Study Plan has been developed in response to comments on the
ICD and through discussions with the Fish and Aquatics IAG, to provide
additional necessary information for consideration in the relicensing process.
The following issue was raised during initial consultation
regarding reservoir fisheries and aquatic habitat at the Yadkin Project:
the effects of Yadkin Project reservoir operations on fish and aquatic
March 12, 2003
the Fish and Aquatics IAG met and discussed objectives for the reservoir
fishery and aquatic habitat study. Over
the course of those discussions the following objectives were identified for the
the existing aquatic habitat in the existing and potential drawdown zones of
High Rock and
reservoirs and the littoral zones of Tuckertown and Falls reservoirs for
inclusion in a GIS based (ARC View) database.
the impacts of fluctuating water levels under existing Project operations on
the existing fishery and aquatic habitats in the four impoundments.
A draft study plan for the Yadkin Reservoir Fish and
Aquatic Habitat Assessment was prepared by Normandeau Associates and distributed
electronically to the Fish and Aquatics IAG on
April 4, 2003
for review prior to the
April 9, 2003
IAG meeting held in
. Comments from the April 9 meeting
have been incorporated into this final study plan.
Comments at the meeting included discussions on the difficulties of doing
the proposed habitat assessment by boat on High Rock during low water because of
the shallow water encountered, especially in the tributary arms.
Another comment was that the draft habitat study plan lacked sufficient
detail on the habitat types that would be mapped and what the final report and
Arc View file would contain. Comments
on the proposed mapping of significant erosion along the reservoir were also
discussed at the April 9th IAG meeting, including what constituted
significant erosion and the impacts of potential erosion on affected resources.
It was agreed that those Participants that were not familiar with
Normandeau Associates Santeetlah Reservoir
Aquatic Habitat Study would be given a copy as an example of the type of
habitat survey and the work product (Arc View) that Normandeau Associates will
provide for the proposed Yadkin Reservoirs Habitat surveys.
A revised draft study plan was distributed to the IAG in
May, 2003 and IAG members and no additional comments were received.
The habitat mapping portion of the study will be conducted
by Normandeau Associates Inc. (NAI) and will entail the following:
aquatic habitat will be mapped in the drawdown zones of High Rock and
in one foot contour intervals during the fall/early winter of 2003 after the
reservoirs have been drawn down. In
order to document habitat conditions in the typical 10-15 foot drawdown zone
within High Rock Reservoir, Normandeau will attempt to map habitat in High
Rock with at least a 10 ft drawdown. A
drawdown greater than these may be possible to achieve for study purposes,
but it is important to recognize that factors such as weather and incoming
flows that are beyond the control of Yadkin can create conditions under
which significant drawdowns of the two reservoirs are not possible.
, Normandeau will attempt to map habitat to a depth of 15 ft in order to
evaluate the potential resource impacts associated with increasing the
annual drawdown of Narrows Reservoir, similar to that currently done at High
High Rock, Normandeau Associates plans to conduct the habitat survey in two
parts – the first effort will focus on the shallow tributary arms when the
drawdown is approximately 5 ft below full pond in late summer or early fall
(depending on the bathymetry in the various coves/tributary arms).
This will enable the field crew to work mostly from a boat in the
shallower areas, which would not be possible during a full 10 to 15 ft
drawdown. The second effort will
occur after High Rock is drawn down at least 10 ft, and at this time the
remaining habitat in the main body of the reservoir and in the deeper areas
of the tributary arms will be mapped. Field
crews may also conduct the
habitat survey in two trips, but this may not be necessary because the
reservoir is generally deeper than High Rock and the area exposed at a 15 ft
drawdown is expected to be significantly less than at High Rock.
will be mapped in the littoral zones of Tuckertown and Falls Reservoirs
(using the same methods cited above) during the fall/early winter of 2004.
Because these two reservoirs have limited storage capability and do
not have significant seasonal drawdowns, attempts will be made to coordinate
and conduct these surveys when the reservoirs are down approximately 2 to 3
ft below high water (if feasible).
surveys at all four reservoirs will be conducted using a Trimble GPS unit
coupled with a laser scope, digital movie camera, laptop computer and Hydro
Pro software. The laser scope will enable a crew to pinpoint and outline
important habitat features to sub-meter accuracy so that habitat area can be
calculated. Habitat types will include, but not be limited to stream
confluences, aquatic vegetation, woody debris (natural and cut), structures
(piers, docks, marinas, etc.), rock habitat – gravel, cobble, boulder and
ledge, and sand/clay habitat. Stream
confluences will be filmed at drawdown to document access between the
tributaries and the reservoir and any blockage will be pinpointed with the
vegetation will be mostly lacking during the fall/winter period when this
habitat work is planned, therefore most of the mapping of aquatic vegetation
habitat types will be done during the proposed wetland and terrestrial
studies during spring and summer, using a combination of stereo overflights
and ground truthing. This effort will quantify the major water willow beds
and other aquatic plants present. Once
this data is collected and mapped, it will be imported into the Arc View
habitat data file for each reservoir.
habitat types that will be mapped include downed trees (natural fall or
cut), brush piles, stumps, standing timber and man-made fish habitat such as
Christmas trees. Downed trees will be further broken down by their size and
the amount of branches remaining on them, such as bare tree trunk, medium
branched and heavily branched trees. Also,
trees that were cut by agencies and cabled together to provide fish habitat
will be differentiated from those that fell naturally or were cut illegally.
and piers will also be layered into the Arc View data file for each
reservoir and this work (including the area of the docks in square feet) has
already be completed by PB Power on High Rock using overflight pictures from
a 2002 survey.
substrate types within the drawdown zone will be delineated and mapped,
including sand/clay (or mud), gravel, cobble, boulder, ledge and rip-rap.
Substrate that does not provide good habitat, such as heavily
imbedded gravel (imbedded >75%) will not be measured.
The predominant substrate type (mud or sand/clay) will not be mapped
by the field crew, but will instead become the “default substrate”.
All habitat types except this category will be mapped, and all other
habitat of lower value that is not mapped will fall into this category.
habitat data from the four reservoirs will be imported into an ARC View data
file after it’s collected, so the amount of aquatic habitat (acres and ft²)
can be calculated. Bathymetry in
all four reservoirs will be presented in 1 ft contour intervals.
the habitat surveys, the entire shoreline of all four reservoirs will be
filmed with a digital movie camera connected to the Trimble GPS unit.
Areas of significant erosion and their extent will be located with
the GPS system (latitude/longitude), filmed during this survey and their
locations included in the Arc View data file for each reservoir.
Significant erosion will include areas that are observed to have
active and ongoing erosion and observable impacts to important aquatic and
terrestrial resources. Such
areas will include but are not necessarily limited to:
where eroding shoreline has resulted in localized sediment deposits that
are noticeably affecting water quality or aquatic habitats
where eroding shoreline has resulted in the loss of vegetation from a
significant plant community or
where eroding shoreline are impacting public recreation facilities
Methods – Reservoir level fluctuation evaluation
The reservoir fluctuation evaluation portion of the study will also be
conducted by Normandeau and will entail the following:
effects of current Project operations and water level fluctuations on
existing fishery and aquatic habitats, including impacts to fish species of
management concern during the spawning season and impacts due to daily and
seasonal drawdowns. Fish species
evaluated will primarily include all those that spawn in the littoral zone,
such as largemouth bass, sunfish species (bluegill, pumpkinseed etc).
Other fish, such as the forage species that are pelagic spawners
(threadfin and gizzard shad, blueback herring) will also be evaluated.
The habitat surveys discussed above will be used to quantify impacts
of fluctuations on fish and aquatic habitats.
Other Project operations that could affect aquatic biota such as
stranding (after generation ceases) and water quality (especially dissolved
oxygen and temperature) will also be evaluated as part of this study.
effects of alternative reservoir fluctuations, such as reduced drawdown
zone, seasonal changes to rule curve (fill reservoir sooner or hold full
existing water level fluctuation and drawdown data for the reservoirs,
calculate median, mean low and mean high water levels from long term data
sets and prepare a graph for a 12-month cycle to assess impacts (this data
will also be used for wetlands evaluation).
existing fishery data (species lists) collected by NCWRC, Yadkin
consultants (recent Progress Energy fish sampling in four reservoirs) and
fisheries data that will be collected during the proposed tailwater
fisheries sampling beginning in August 2003 to conduct this evaluation.
Data Collection and Reporting Schedule
Data collection for the habitat surveys on High Rock and Narrows
Reservoirs are planned for the fall
and early winter in 2003 and the habitat data collection for the Tuckertown and
Falls Reservoirs is planned for the fall/early winter in 2004.
Results of the habitat surveys and reservoir fluctuation evaluations for
the four impoundments will be reported in draft and final study reports.
A draft study report of the habitat surveys on High Rock and Narrows
Reservoirs will be prepared and distributed to the Fish and Aquatics IAG for
review and comment by the 1st quarter of 2004, approximately two to three months
after the completion of data collection. A
draft study report for the Tuckertown and Falls Habitat survey will be prepared
and distributed to the Fish and Aquatics IAG by the 1st quarter of
2005, approximately 2 months after data collection.
IAG comments will be addressed in a final habitat study report for all
four reservoirs that will be distributed to the IAG in March 2005.
Interim results, such as draft habitat maps of the reservoirs, may be
shared with the IAG as such information becomes available, prior to completion
of the draft study report. The draft
Reservoir Level Fluctuation report for High Rock and
will be prepared and distributed to the IAG for review and comment by the 2nd
quarter of 2004, about three months after the draft Habitat survey report for
these two reservoirs is turned in. The
draft Reservoir Level Fluctuation report for Tuckertown and Falls Reservoirs
will be distributed to the IAG for review and comment by the 2nd
quarter of 2005, about two months after the draft habitat survey for these
reservoirs is turned in (draft habitat survey reports are needed in order to
complete the draft reservoir fluctuation reports).
Final Reservoir Level Fluctuation reports for the four reservoirs will be
distributed to the IAG for review and comment by the 2nd quarter of