Songo "Non-Beach" at Sebago Lake State Park, July 1999.
10.
Request for FOSL's proposed lake management alternative to be given an in-depth
analysis by the Commission.
FOSL recommends the Commission identify specific lake level management options
in the EIS and analyze each, as was done for Sebago Lake in FERC (1997).
FOSL agrees with the information and recommendations presented to FERC by
Steven Kasprzak in his oral and written scoping comments dated 22 October
2002. In addition to Mr. Kasprzak's recommendations, FOSL recommends that
the level of Sebago Lake should be lowered to the 10th percentile at least
once a decade, as recommended by Normandeau (1994). The 10th percentile
levels must be reached in the late summer. This lowering should occur in
the next three years and during this year the overall annual lake level
range should not exceed six feet. Because of the eroded and vulnerable condition
of the shoreline, the highest level should be 266 msl on June 1st. Outflows
should be adjusted immediately to return the lake below the 266 msl level
when lake inflows increase.
FOSL's recommendation for a lake management plan is as follows:
1. Follow the 1996 FERC Staff plan with modifications.
2. Allow lake levels to reach the 25th percentile by November 1 every other
year.
3. Lake levels should not exceed 266 msl.
4. Lake levels should be allowed to reach the 10th percentile once a decade.
Maximum drawdown during that year should not exceed 6 feet.
The FOSL recommendation is a compromise. Based upon its research, FOSL believes
that a plan allowing for more intra-annual variability and less stable water
levels in the growing season would be more ecologically sound. FOSL does
not recommend large unnatural winter drawdowns. FOSL questions whether the
peak lake levels should be earlier in the spring for ecological reasons.
Studies on other lakes exists which were never utilized in the 1997 FERC
EIS. Many of these can be found in the FOSL bibliography of studies pertaining
to lake regulation. This list can also be located on the FOSL web site:
www.friendsofsebago.org.
Lake Ontario is an example where a compression of the range and an increase
in the annual mean has caused serious ecological problems. Decades of high
water levels on Lake Ontario have eroded away most of the protective beaches
and have left banks and bluffs unprotected and vulnerable to severe erosion.
The loss of these protective beaches has accelerated erosion and flooding
along the South shore of Lake Ontario to the point where property losses
of as much as 40 ft. in a 24hr.period are not uncommon (See http://www.loranet.org/bac.htm)
Rainy Lake in Voyageurs National Park has been compared to Sebago Lake by
FERC (FERC 1997 EIS-2984-042, Sect. 4-17):
"These lake systems are similar in size, morphology, and water level
regulation patterns to Sebago Lake."
FERC (1997) did not mention that Rainy Lake had significant erosion problems.
Erosion problems were noted in the International Rainy Lake Board of Control
IRLBC- Final Report - Review of the IJC Order for Rainy and Namakan Lakes
October 26, 1999:
"Erosion and damage to shoreline development is known to occur throughout
the area, especially under conditions of high water in conjunctions with
strong winds. Erosion is especially problematic on the south shore of Sand
Bay on Rainy Lake .... shoreline erosion was reported as a significant concern
by only a small number of respondents to a damage survey done by the International
Steering Committee. Many residents have built breakwaters or have rip-rapped
the shoreline to reduce damages. " (IRLBC)
"Another consideration in this resource category is the fact that archaeological
surveys conducted along these lakes have shown that there are numerous prehistoric
and historic Indian cultural sites located along the shorelines. Information
provided in the International Steering Committee Report indicates that about
75 percent of the sites have been partially destroyed by the rise in lake
levels resulting from the construction of the dam."
Little attention has been afforded the importance of shoreline vegetation
on Sebago Lake. In areas of natural shoreline without developments vegetation
has been eroded away. This vegetation is a key to dissipating the impacts
of wave action. Vegetation and root structures can successfully prevent
erosion during periods of high water levels. Sustained periods of high water
and storm action can destroy this natural shoreline protection. This the
case on the natural shoreline of Long Point in Standish.
U.S. Army Corps of Engineers (1985) states:
"As a result of rising water levels or constantly fluctuating water
levels vegetation is killed by inundation. This may occur during the winter
(McKim et al. 1975) as well as during spring flooding. The vegetation cover
and root system help dissipate wave, current and wind energy on low-lying
beaches during storm and other temporary water surges. In addition, they
resist sub-aerial erosion by overland flow during spring runoff and rainstorms,
and their loss can result in accelerated erosion (e.g. Hunt et al. 1976,
Pincus 1962, 1964) Nikolayenko (1974) observed that a dense shrub cover
retarded or stopped breaking waves during storms on 3 to 4 meter high bluffs.
Furthermore, sediments in bluffs are effectively strengthened by extensive
vegetation and thus resist erosion and failure (Smith 1976). Berg and Collison
(1976) found that bluff recession actually lagged behind the rising water
level in Lake Michigan. In the late 1960s because of protection by vegetation.
With the onset of falling water levels, recession of the lake bluffs continued
until vegetation had reestablished itself."
The reestablishment of shoreline vegetation on Sebago Lake's eroded shorelines
is an indicator of the success of a water level plan, therefore FOSL requests
an analysis of the reestablishment of shoreline vegetation in the Eel Weir
EIS.
FOSL believes the existing beach profiling studies are inadequate to measure
the amount of erosion occurring around Sebago Lake. Bluffs are eroding at
levels below full pond and there are no profiles to measure this erosion.
Without measuring profiles to depths of 15 feet below 266.65 msl there is
no means to gauge the movements of sand under the water. This is critical
to determine the impact of the present plan on erosion and accretion. Beach
profiles near the point of a beach are compromised by the deposition of
eroded material from the bay. Some beach areas will maintain their form
until the introduction of eroded material ceases. Sand bar beaches appear
to be moving in order to adjust to the new higher water levels. This appears
to be the case of the Standish Sandbar and the Songo Sandbar.
FOSL requests that beach profiling continue with but added improvements
as a condition of the relicensing for the Eel Weir dam. Shoreline monitoring
should include eroding bluffs and sand bars. FOSL requests that bottom profiling
be taken in front of Thompson Point developments and other areas identified
with offshore erosion problems. FOSL requests that shoreline profile data
collection include profiles to 251.65 msl .
Many eroded areas have been armored with shore protection. This has caused
a substantial impact on the ecology and aesthetic nature of Sebago lake.
The new Portland Water District Rt. 35 rip rap is an eyesore vislble for
miles. FOSL has recorded the erosion and recession of Sebago Lake's shorelines
on photographs. The attached photos are testimony to the substantial recession
and damage to Sebago lake shorelines caused by the licensee's post-1987
management of outflows from the Eel Weir dam.
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