Earthplace: Norwalk River swimming in E. coli bacteria

By Tim Stelloh, Staff Writer, The Advocate, December 4, 2007

NORWALK - The dry summer should have helped the Norwalk River.

Instead, the amount of E. coli bacteria in the water was significantly higher than allowed by the state Department of Environmental Protection. In many instances, levels were higher than last year, said Dick Harris, head of Earthplace's River Watch program.

Harris recently completed a water quality report analyzing E. coli levels in the river from early May to late September.

"It was a dry summer, so the river should have looked its shining best," he said. "There was a lack of stormwater runoff . . . but we still flunked."

Of 12 sites measured from the Post Road in Norwalk to the Branchville Railroad Station and the Stonehenge Inn & Restaurant in Ridgefield, only one met state requirements, he said.

That site, an outflow pipe at a Ridgefield wastewater treatment plant, measured far better than any other, with only two bacteria cells for every 100 milliliters - or enough water to fill a tube the size of a large cigar, Harris said.

Nearly all of the bacteria from the plant are zapped with ultraviolet light before they reach the river, he said.

State requirements allow 126 cells of E. coli for every cigar-size tube of water. If that criteria was met, Harris applied a DEP-required secondary test that looked at bacteria frequency during his four months of testing. If the measurements did not meet both requirements, the site failed.

The Post Road area in Norwalk had the highest bacteria levels, with 450 cells per tube. Harris collected nearly as many cells from a sampling site near the Merritt Parkway and Route 7.

Last summer, when more rain fell, bacteria levels were lower, except at Silvermine River, Old Mill Road in Wilton and Steep Brook in Ridgefield. Bacteria counts at the Post Road site in Norwalk were the same as last year.

Causes for the elevated bacteria counts include leaky septic tanks releasing effluent directly into the river, animal waste, runoff and bank erosion. Lawns increasingly go all the way to the river, with no buffer between them and the water, Harris said. Lawn fertilizers can increase bacteria counts in the river.

Tony D'Andrea of the Mayor's Water Quality Committee in Norwalk said developments upstream in Redding and Ridgefield increase pollutants.

"That water is going somewhere," D'Andrea said.

Harris said it's difficult to pinpoint why this summer's bacteria levels were higher.

"Our theory is that there was more rain (last summer) to dilute the same amount of bacteria. We had a very wet summer, so the ground was flushed continually. There were no piles of dog poop or goose poop," he said. "This summer was dry, so it wasn't diluted."

Making annual comparisons can be difficult because a couple of heavy rainstorms sandwiched into an otherwise dry season will skew the numbers, Harris said.

"It's inexact," he said. "But it's all we have."

The DEP determined that the river is a "non-designated swimming" area, according to Harris' report. Patrice Gillespie, head of the Norwalk River Watershed Association, is trying to change that.

The group is holding a goose egg oiling workshop this winter to help reduce the number of Canada geese, and is pushing for better management of landscape and animal waste.

"Riparian buffers are so important - those shrubs and grasses can filter out nutrients," Gillespie said. "But it depends on the property owners. There are so many places where people mow right down to the water's edge."

Gillespie said she looks to the Saugatuck River for inspiration.

Of the 18 sites Harris measured in that watershed over the summer, nine met state standards, according to a River Watch report. The big difference between Saugatuck and Norwalk is 16,000 acres of protected land at a watershed reservoir, he said.

"Civilization is more spread out" by the Saugatuck, he said. "By the Norwalk River, that's not the case."