In a regulatory filing dated May 14, 2010, Friends of the Sebago Lake has recommended to the Federal Energy Regulatory Commission that a minimum flow of 250 cubic feet per second be required at the Eel Weir Dam at the outlet of Sebago Lake to protect downstream water quality.
A recent study by the Maine Dept. of Environmental Protection shows this outflow at Sebago Lake is necessary to ensure that dissolved oxygen levels in the lower Presumpscot River remain at the very high levels they are now achieving, which meet Maine Class A and Class B water quality standards.
See this story for more details.
UPDATE: The S.D. Warren wastewater treatment plant license carries the following minimum outflows from Sebago Lake between May 1 and Nov. 1:
a) A minimum outflow of 333 cfs (20,000 cfm) when the lake is within its target range.
b) A minimum outflow of 270 cfs (16,400 cfm) when the lake is below its target range.
c) An 'emergency' outflow of 250 cfs (15,000 cfm) when the lake is more than 1 foot below its target range; but only after flows have already been lowered to 270 cfs for at least four weeks.
Friday, May 14, 2010
Wednesday, May 12, 2010
Scientific Proof that Stopping Pollution and Removing Dams Fixes Rivers: Lower Presumpscot River now meets Class A standards.
By Douglas Watts
Friends of Sebago Lake
Until 1999, the Presumpscot River near Portland, Maine was perhaps the filthiest and most polluted river in New England. Then two things happened. First, in July 1999 the S.D. Warren Paper Company shut down its paper pulp making operation in Westbrook, Maine, removing a giant gob of organic pollution from the river. Then, in 2002, the head of tide Smelt Hill Dam was removed. This dam, built in the early 1900s, created a seven mile long stagnant pond which allowed the paper mill pollution from S.D. Warren to fester and settle in the river and consume most of its dissolved oxygen.
The first underwater photos ever taken of native blueback herring
and American shad (the big fish) ascending Presumpscot Falls,
Presumpscot River, Portland, Maine. June 6, 2009.
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This is the falls they were swimming up through.
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The report's findings are quite astounding. Prior to 1999, the Presumpscot could barely meet Maine's Class C water quality standards, which require 5 parts per million (ppm) of dissolved oxygen in the water at all times. The 2008 study found that what had been the most polluted reach of the river, below the S.D. Warren paper mill in Westbrook, now easily attains 7 parts per million of dissolved oxygen, even under high temperature, low-flow conditions. This means the lower Presumpscot River is now in full attainment of the dissolved oxygen standard of Maine's highest water quality classification, Class A, which requires 7 ppm of dissolved oxygen at all times. The study report states at 8:
"Early morning dissolved oxygen (DO) readings on the Presumpscot are compared to the minimum class C criteria of 5 ppm. In all cases, criteria are easily met and always exceeded 7.0 ppm."
It might seem at first glance that the difference between 5 ppm and 7 ppm of dissolved oxygen is not a big improvement or a big deal, but it is. Dissolved oxygen standards were created under the Clean Water Act and Maine law because they accurately determine what and how many aquatic organisms, including fish, can inhabit a river. Even in the most clean rivers and streams, the upper limit of dissolved oxygen levels is around 10 ppm, so it's a fairly narrow window, and native critters of Maine rivers have evolved to live in waters with 7-9 ppm. Dissolved oxygen levels above 7 ppm allow all of Maine's aquatic life to happily inhabit a river and reach their fullest potential. When dissolved oxygen levels fall below 7 ppm that aquatic life, oxygen-intensive aquatic animals like ...
native brook trout ... |
Atlantic salmon ... |
and stoneflies .... |
... start to suffer and eventually disappear. Any aquatic biologist in Maine will tell you that while Maine's Class C standards require at least 5 ppm of dissolved oxygen, this is far from optimal, sort of like saying that technically a prisoner can live on bread and water ... for awhile ...
Here is a story from 1999 about the first, fledgling efforts to rescue the Presumpscot River from continued oblivion.
During the 1960s, 1970s and 1980s, very few people, including scientists, ever believed the Presumpscot River would attain Class A water quality during their lifetimes. During this period and in the decades prior, most people in southern Maine, and those who lived along the Presumpscot, had long given up hope that the Presumpscot River would ever be clean again. The challenge seemed too daunting and the prospect too remote. What then seemed a fantasy is now the reality. It has been done. It can be done.
Until 2002, these waterfalls on the Presumpscot River in Portland, Maine did not exist and this was the dirtiest river in New England.
In the end, it's always about what we consider valuable.
Saturday, May 8, 2010
Severe Nutrient Loading at China Lake Outlet Stream, Winslow, Maine, October 2010.
The above photos were taken in China Lake Outlet Stream at the Garland Road Bridge in Winslow in October 2010 showing extremely thick growths of filamentous algae growing in the stream bed.
This area is about 100 yards above the confluence of China Lake Outlet Stream with the Sebasticook River. The stream here is shallow and fast moving, which discounts the Sebasticook River itself as being the source of the nutrients encouraging the algae growth. This algae is growing in stream water solely from China Lake Stream.
This type of algae growth, especially at this density, is not due to naturally occuring conditions. From our understanding and experience, filamentous algae growths like these in a fast-moving stream are indicative of a nutrient surplus of nitrogen or phosphorus or both. These algae growths suggest a possible contribution of the Kennebec Sanitary District wastewater discharge, located several miles upstream in East Vassalboro, in addition to non-point source inputs along the stream (cow manure, faulty septic systems, lawn fertilizer, etc.).
As you can see in the photos, the growths are so thick that they are destroying most of the aquatic insect and fish habitat in the stream where the algae is growing. This stream reach should be (and could now be) Atlantic salmon spawning and juvenile rearing habitat. There are now Atlantic salmon documented to be ascending the Sebasticook (4 large adults were passed at Benton Falls Dam in 2009). These salmon and their offspring are protected as endangered species under the U.S. Endangered Species Act.
Earlier in 2009, in September, on a field trip a mile farther upstream to examine a streamside archaeological site, myself (Doug Watts) and Bruce Bourque, chief archaeologist with the Maine State Museum and Bob Doyle, retired Maine State Geologist, observed similarly thick growths of filamentous algae in the streambed.
An open question is whether the manipulation of outflows from China Lake, now regulated to provide sufficient 'dilution' for the KSD wastewater, is contributing in some way to this stream degradation. We are now looking into this.
Here are two stills from the video, shot in September 2009. The streamers of algae are about 6 feet long. Unpolluted streams do not have algae growths like this.
Severe Beach Erosion at Smooth Ledge Beach, Sebago Lake, April 22, 2010
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