HomeMy WebLinkAbout19910326 Ver 1_Staff Comments_19940811Roger Thorpe
John Dorney
Alan Clark
Ken Eagleson
Don S afrit
Ruth Swanek
Juan Mangles
Monica Swihart
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AUG l994
Attached is a slightly revised version (although the dates are the
same) of the letter Monica sent with our comments on the Lake
Gaston pipeline project. Please discard the copy you have and
replace it with this one for your files. The reason for the revised
version was to include some sections on basinwide planning and
water quality standards. Since I also made a small technical
change in a portion of the orginal letter, I decided it was better
not to send another official version which tried to make the
corrections and additions. It was just simplier to add the
material that was orginally intended for the first version.
'& d
July 25, 1994
MEMO
TO: Monica Swihart
FROM: John Dorn9p
RE: Wetlands-related o ments
project
on Lake Gaston pipeline
The following comments should be addressed in the Final EIS
for this project. We believe that the potential for impacts on
wetlands along the lower Roanoke River Basin and riparian
wetlands adjacent to upper lake segments are possible from this
project. The following information will allow us to examine this
issue.
1. Document the extent, types and functions of all wetlands
along the Roanoke River (including those adjacent to the upper
reservoirs) and its tributaries downstream of the Lake Gaston Dam
within the 10 year floodplain. The 10 year_floodplain was
selected since these wetlands are the ones most likely to be
affected by lower flows.
2. Document the effect on extent, types and functions of
any wetlands in the 10 year floodplain downstream of the Lake
Gaston Dam that would be effected by reduced low flow.
3. Document any changes anticipated in wetland extent,
types and functions due to reduced high flows along the Roanoke
River and its tributaries downstream of the Lake Gaston Dam.
Particular emphasis should be given to any effects on wetlands
along tributaries.
4. Document any effect on the extent, types, and functions
of wetlands along the margin or the upper end of Lake Gaston,
Roanoke Rapids reservoir, Lake Philpott or Kerr Lake due to
changed flow regimes as reflected in lake water levels which are
lower as a result of this withdrawal. Of particular interest is
any reduction in sediment removal rates or nutrient
transformation due to reduced inundation in these wetlands. This
reduction in pollutant trapping could have direct effects on
water quality in the lakes and Roanoke River.
5. Document any effects on BOD and dissolved oxygen due to
reduced flows. This is a crucial item for eventual 401
Certification for the renewal of the FERC license for the dam.
Please call me at 733-1786 if you have any questions.
gastones.com
cc: Ron Ferrell
DEM Washington Regional Office