SOUTH PORTLAND — South Portland is a step closer to creating a plan to ease the effects of development on the Trout Brook watershed.

With a $35,300 state grant, the city will be able to start work on a management plan for the watershed. The money from the state Department of Environmental Protection will pay for a consultant who will work with the city’s staff and others to develop the plan. The city will provide $23,807 in staff time and $2,113 in cash.

Trout Brook and Kimball Brook, which flows into it, are considered “urban-impaired” streams that don’t meet federal Clean Water Act standards. The watershed’s problems include stormwater runoff, low levels of dissolved oxygen, a high concentration of metals and damage to aquatic life.

“Urbanization has created issues with the streams that flow through South Portland,” said Pat Cloutier, director of the South Portland Water Resource Protection Department.

The watershed, covering more than 2½ square miles in South Portland and Cape Elizabeth, includes forest, residential and commercial areas. Trout Brook is most visible as it flows through Mill Creek Park on its way to the Fore River and Casco Bay.

The other urban-impaired streams in the city are Red Brook, Barbary Creek and Long Creek, which is the focus of an extensive effort to reduce runoff pollution.

Despite the problems in the Trout Brook watershed, there are some bright spots. Most notable are areas that support native brook trout.

“A lot of people may not know they’re there, but they’re there,” said Richard Rottkov, president of the South Portland Land Trust. “I wouldn’t say they’re winning the battle, but they’re holding their own.”

The presence of trout means oxygen levels aren’t too low, the insects they eat are surviving and water temperatures are sufficiently cold. Pollution can pull down oxygen levels and harm insects and other invertebrates. A loss of shade trees and the addition of runoff from impervious surfaces like asphalt can cause water temperatures to rise.

Research shows a close relationship between unhealthy streams and impervious surfaces such as roads, parking areas and rooftops, said Curtis Bohlen, director of the Casco Bay Estuary Partnership. He said the amount of impervious surface is the easiest way to measure the effects of urbanization, but factors like removing trees and filling a floodplain also contribute to the problem.

“One of the things that makes Trout Brook interesting as an urban-impaired stream is that it’s not as dreadfully impaired,” Bohlen said. “Here’s a place where we might be able to get more bang for our buck.”

The management plan will include an assessment of the causes of stream impairment and how they should be remedied, said Don Witherill, director of the DEP’s watershed management division.

“That’s basically the first step in trying to restore the stream: to figure out what the actual sources are that they need to deal with,” he said.

The DEP, the land trust and the estuary partnership are among the groups that have agreed to participate in the restoration effort with the city. Others include Cape Elizabeth, the Cape Elizabeth Land Trust, the Friends of Casco Bay and the Maine Board of Pesticides Control.

Staff Writer Ann S. Kim can be contacted at 791-6383 or at:

[email protected]