Warren officials don’t fully know why bacterial pollution is still an issue at the Warren Town Beach, after the town spent more than $2 million over the past several years repairing sewer and other infrastructural issues surrounding the beach.

Officials hoped that the town’s work to improve drainage and sewering around south Water Street several years ago, and doing more work along Campbell Street over the past year, would help clean up the beach and lead to a reduction in the number of days the state orders it closed to swimming.

But with two recent closures — once for two days in late June, and again last week — Warren Town Manager Jan Reitsma said he doesn’t know what the problem is.

“As far as I know, improvements made to both (the) sewer and storm water infrastructure are working well,” he said. “I do not have a definitive answer” as to why the closures continue.

State Department of Health monitors ordered the beach closed last week after finding concentrations of Enterococci bacteria in the water exceeding 60cfu (colony forming units) per 100 milliliters of water. After two days, the bacteria, which are found in the presence of feces, had fallen enough to allow the beach to re-open.

With area sewers and water infrastructure reportedly working as designed, Mr. Reitsma said he asked the managers of Warren’s wastewater treatment plant for answers following the first closure in late June. Operators responded that they had no operational issues and hadn’t exceeded their effluent levels. However, they gave a possible explanation for at least some of the recent hiked bacteria levels: Birds.

Plant managers said that in their experience, closures are sometimes related to the large number of birds that gather in significant numbers at the beach.

“When we have rain and storm water runoff, it tends to flush the accumulated feces into the water,” he said, which leads to a jump in the bacteria count.

“Unfortunately some animal lovers make matters worse by feeding the birds, which keep coming back for more,” Mr. Reitsma said.

Another possible source could boats and illegal pump outs or dumping of waste, but Mr. Reitsma said he has no evidence that that is occurring in the Warren River.

Mr. Reitsma said that if closures start becoming more frequent, the town will likely have to call in experts to take a look at the problem and determine the source of the pollution.

“The Department of Health will no doubt let us know if and when that becomes necessary.”