PORTLAND – Nearly half of Maine construction sites violate the soil erosion laws that protect lakes and streams from pollution, a state survey has found.

The survey, conducted by the Maine Department of Environmental Protection last summer, examined more than 800 construction sites in 88 communities. It found that 44 percent were not taking appropriate erosion control measures.

Residential construction was the worst offender, with 53 percent of single-lot building sites ignoring erosion control practices such as mulch. Contractors who had taken soil erosion certification courses fared much better.

The survey results were so striking that the state has begun considering mandatory certification, said Don Witherill, director of the agency’s division on watershed management. Such a move would have to be passed by the Legislature.

John Butts, executive director of Associated Constructors of Maine, said his members – mostly larger contractors – have not yet taken a position on the issue of mandatory certification, but he said they are skeptical.

“We want to focus on the problem, and if making it mandatory is the solution, then we’re going to have to take a look at that,” Butts said. “But I don’t think our guys are convinced that making it mandatory is the entire solution.”