Maryland Department of the Environment officials said a 35-year-old, under-enforced federal regulation could now mandate that levels of fecal bacteria in a sprawling Carroll County watershed be reduced by more than 90 percent, though the state did not suggest yesterday how to improve water quality.
Carroll County officials said they have anticipated costly wastewater treatment plant upgrades as the federal government starts to implement more of the 1972 Clean Water Act. It requires states to identify polluted waterways and set limits for each source of contamination.
But environmental officials acknowledged yesterday that such stringent requirements were going to be difficult to enforce.
"We recognize the challenges that everyone faces with this," said Tim Rule, watershed modeling division chief for the state Department of the Environment. "The jurisdictions are expected to address the practical reductions first."
Dinorah Dalmasy, head of the environmental department's water quality modeling division, said Carroll County's Double Pipe Creek watershed has one of the state's highest levels of E. coli bacteria contamination. But she said other waterways across Maryland are facing similar problems.
Spanning 120,000 acres in Carroll and a slice of Frederick County, the Double Pipe Creek watershed is polluted by failing septic systems, sewer overflows and roaming livestock in the agriculturally-rich area, Dalmasy said.
It encompasses five municipal or county wastewater treatment plants, in Westminster, Union Bridge, New Windsor, Pleasant Valley and at the former Bowling Brook school site. The watershed also includes 7,600 septic systems.
Fecal bacteria levels were the highest in a section of Little Pipe Creek near Union Bridge, officials said.
The state has determined that E. coli bacteria should not exceed 126 colonies per 100-milliliters of freshwater. But officials said the Little Pipe Creek section had an annual mean of 1,575 bacteria colonies per 100-milliliters of water sampled, according to Dalmasy's report to Carroll officials.
Swimming or fishing in the creek could lead to a serious gastrointestinal illness, officials said.
During dry periods, cattle were found wading into the water there, which could spike E. coli levels, Dalmasy said.
Pets contribute 37 percent of the E. coli pollution in Double Pipe Creek, while livestock was responsible for 29 percent of the sum, the report stated.
Sewer overflows also occurred five times in the watershed during the 2003-2004 sampling period.
To track the cleanup progress, Dalmasy said the state plans to do a yearlong water quality assessment at Double Pipe Creek and other polluted sites every five years.
But Carroll County officials said they first need more support from the state.
"What kind of actions are being taken to try to achieve these targeted reductions?" county planning director Steven C. Horn asked.
A wave of lawsuits in the 1990s pushed the federal Environmental Protection Agency to start forcing compliance with the Clean Water Act.