ROCKLAND, Maine — The city is trying to determine the source of pollution that has led to an E. coli level more than seven times greater than what is considered safe at one spot in the harbor.

The wastewater plant director said, however, the pollution appears to be restricted to an area near the stormwater discharge pipe at Snow Marine Park and does not extend out further into the harbor. Snow Marine Park is a popular place for people to launch boats.

The elevated bacterial count was first detected by the Maine Department of Environmental Protection a little more than a week ago while it was testing several selected Maine harbors. The city followed up last week and did its own test and found the E. coli count was 2,700 spores per sample, far more than the 400 limit, according to Terry Pinto, director of the wastewater treatment plant.

The pollution was found at the end of a 36-inch-wide pipe that is supposed to only be draining off stormwater from Snow Marine Park and a section of the city’s South End.

While no cause has been pinpointed, Pinto said it could be the result, at least partially, of dog droppings from pets that frequent Snow Marine Park. The city has an ordinance that requires people to pick up after their dogs, but the lack of cooperation by some dog owners has been an issue raised in the city.

Pinto said he has decided to have a $1,000 test done of the water samples that will determine from what species the bacteria originates. He said the test will be able to determine whether the bacteria came from humans, dogs, seagulls, raccoons or other animals.

The city has sent cameras, attached to small remote vehicles, up the stormwater pipe to help find the source but has not found it, according to Pinto. He said the camera work will continue, sending the camera further up the line.