Sparkling on a bright fall afternoon this week, Amos Lake hardly looked deserving of its "impaired waters" label.
Yet often in the summer months, when boating, fishing and swimming season peaks, thick algae and invasive weeds make parts of the 113-acre lake off Route 164 in Preston uninviting at best.
"The weeds are so thick by the state boat launch, it's frightening," said Pat Monahan, president of the Amos Lake Association, as she showed photos of algae goop and pond weeds. "You look at it today and it looks beautiful, but if you came here in the summer and saw those clumps of algae, would you want to swim in that?"
Amos Lake and Flat Brook in Ledyard are two of 462 on the state's 2012 "impaired" waterways list, compiled every two years by the state Department of Energy and Environmental Protection. The list, said Eric Thomas, DEEP environmental analyst, is one of the agency's responsibilities under the federal Clean Water Act, a landmark environmental law that took effect 40 years ago today.
Besides being examples of what environmental advocates consider some of the unfinished business of the Clean Water Act, Amos Lake and Flat Brook also illustrate the kinds of small-scale water quality problems that occur on a local level.
While the act is widely considered a success at curtailing the most obvious pollution sources from factories and sewage treatment plants, progress at addressing the kinds of problems like those found at Amos Lake and Flat Brook has been slower, and in some ways, proves more difficult, Thomas said.
Compromised water quality in the lake and the brook is the result of so-called "non-point source" pollution - the kind that comes from runoff from farms, roads, lawns and storm drains, rather than from a single, discrete, identifiable source like a factory discharge pipe.
"We've made a lot of strides, but we still have a long way to go," said Katherine Baer, senior director of the Clean Water Program of American Rivers, a nonprofit advocacy group. "Forty percent of the streams in this country are still considered to be in poor condition."
The major culprit, she said, is non-point source pollution. Gaps in the standards set by the Clean Water Act, she said, include pollution from agriculture. Upgrades in the requirements for discharges from municipal storm drains and sewage plants also are needed, she said.
In the case of Flat Brook, which courses through the Gales Ferry section of Ledyard, high levels of E. coli bacteria landed the stream on the 2008, 2010 and 2012 impaired waterways lists. Often the product of runoff from failing septic tanks, E. coli also can be an indicator of other potentially harmful bacteria.
Excessive nutrients possibly carried in by storm drains and agricultural and lawn runoff to nourish the algae and the weeds are what plagues Amos Lake, Thomas said. Amos was on the 2006, 2008, 2010 and 2012 impaired waters lists.
"We have to deal with these problems on a watershed-wide basis, and find out where the shared responsibility is," he said.
This year, the Eastern Connecticut Conservation District, a nonprofit agency based in Norwich, has been leading projects on both Amos Lake and Flat Brook to better identify the problems and develop a plan. Both are being funded with federal Clean Water Act grants provided by the Environmental Protection Agency and administered by DEEP.
The projects, said Judy Rondeau, natural resource specialist with the district, involve teams of volunteers, trained by her agency, conducting regular water sampling and testing.
Monahan, the Amos Lake association president, said her group reached out to the district when the lake made the list.
"We really felt something needed to be done, but realized that we're on our own, no matter what the Clean Water Act says," said Monahan, who has owned a house on the lake since 1992, and moved there full-time in 2006. The association, with about 15 active members, has been working to educate lakefront property owners about how lawn runoff, poorly maintained septic tanks and sloppy landscaping practices can contribute to nutrient overload in the lake.
Monahan and her husband, Bob, along with other volunteers, this year began working with Rondeau and Jean Pillo, watershed conservation coordinator at the district, to test samples from the lake and from the storm drains and streams that feed into it. Once two years of data are collected, Rondeau said, a plan will be written. The proposed solution is likely to involve changes in land-use practices around the lake and on surrounding roads and farms, meaning town and regional agencies may be asked to play a role.
"With non-point sources, you can't point your finger and say, 'There's one person who needs to change their ways,'" Rondeau said. "It's everywhere, and everything and everybody."
Anne Roberts-Pierson was among the volunteers who worked with the conservation district this summer to collect water samples from Flat Brook, which were taken to the Ledge Light Health District. The Gales Ferry resident said she became involved out of concern about high bacteria levels.
"That brook drains into a pond, and people swim in that pond," she said. "What does that mean for our neighbors using that pond?"
Next week, Roberts-Pierson will hike the shores of the brook for the second phase. Rondeau said she and the volunteers will note any conditions that may be contributing to the pollution. Like Amos Lake, Flat Brook will have a cleanup plan.
Jacqueline Talbot, river steward at the Connecticut River Watershed Council, said involving volunteers and educating the public about the remaining water quality challenges is essential to fulfilling the promise of the Clean Water Act.
"Even in the Northeast in 2012," she said, "we face water quality challenges with significant public health, environmental and economic ramifications."
That includes her group's current focus - working for consistent water quality standards throughout the entire four-state Connecticut River watershed, and stopping the 1 billion gallons of raw sewage and stormwater that pollute the Park and Connecticut rivers annually.
"Connecting people with our water resources is important because people protect that to which they feel a connection," she said.