BIRCH BAY - Manure runoff from a dairy farm has been identified as one source of fecal coliform bacteria that contaminated part of Terrell Creek and caused the beach closure near where the creek empties into the south end of Birch Bay.
The beach has been closed since Jan. 31, after routine sampling Jan. 30 showed very high counts of fecal coliform in the creek from the Kickerville Road bridge down to the creek's mouth.
Fecal coliform bacteria come from human and animal feces.
The state Department of Agriculture is investigating the incident and is working with the landowner on cleanup.
The state agency isn't naming the dairy because the investigation hasn't been completed.
"We could find there are other sites that are a factor in this," said Agriculture spokesman Hector Castro.
The agency also will determine if there have been violations of the state's Water Pollution Control Act.
People have been told to stay away from the contaminated water because contact could cause gastroenteritis, skin rashes, upper-respiratory infections and other illnesses. Pets also should be kept out of the water.
Children and the elderly may be more vulnerable to waterborne illnesses.
"It's fortunate that this is not the busy time of the year," said Tom Kunesh, environmental health supervisor with Whatcom County Health Department, of the public's use of the closed beach.
Public health officials closed the beach. It will stay closed until test results show that the source of contamination has been eliminated, according to Kunesh.
Routine sampling on Jan. 30, on the upper part of the creek, showed counts that were about 30,000 fecal coliforms per 100 milliliters, according to Erika Douglas, senior planner for Whatcom County Public Works.
That was above one allowable threshold, which is an average of 50 fecal coliforms per 100 milliliters.
Results also exceeded another threshold, which is that not more than 10 percent of the samples in a set can exceed 100 fecal coliforms per 100 milliliters.
Down at the mouth of the creek, the levels were about 3,000 fecal coliforms per 100 milliliters.
Follow-up sampling shows that bacteria levels in Terrell Creek have gone down, but levels in the ditch system that feeds into the creek were still high.
Reach Kie Relyea at 360-715-2234 or email@example.com .