KENNEWICK -- Most people have heard "don't eat the yellow snow" in winter, but few think about what lurks in warm river water.
The state Department of Ecology is warning potential swimmers, boaters and anglers about rising levels of fecal coliform bacteria in local waters during warmer summer months, and to be cautious about accidentally ingesting waste.
"Usually between April and October there is an increase in bacteria growth, viruses and parasites in relationship to the warming weather," said Ecology spokeswoman Joye Redfield-Wilder. "It's a precautionary thing."
Fecal coliform bacteria comes from human and animal poo that trickles into creeks, streams and rivers from leaking septic systems or agricultural runoff.
It can get into the water from accidental spills, such as the two that dumped sewage into the Yakima River in recent weeks.
It also can come from manure applied to fields, like the liquid manure that was washed into a roadside ditch in Outlook and ended up flowing into Sulphur Creek and the Yakima River. DeRuyter Brothers Dairy was fined $22,000 when water samples showed the runoff had 2,400 times the levels of E. coli bacteria allowed by state standards.
But it doesn't take a big spill to contaminate water, Redfield-Wilder said.
Ecology officials always observe higher levels of fecal coliform during warmer months, she said. It can come from normal agricultural activities, or can be carried into streams and rivers in runoff when pet owners don't scoop up after their pooches.
The bacteria can make people sick -- usually with stomach cramps or diarrhea -- if they swallow contaminated water. It also can infect open cuts or sores.
But it also can be an indicator that other germs, viruses or parasites are present.
"Fecal coliform is an indicator bacteria," Redfield-Wilder said. "If it is found, then other types of bacteria are likely there as well."
Bruce Perkins, environmental health director for the Benton-Franklin Health District, said sources of fecal coliform exist year-round, but more people are exposed to the bacteria as warm weather leads to water recreation.
"More people are coming into contact with the water and don't realize it's not as safe to swim in and be around," he said.
Health officials also have recommended recently that people avoid direct contact with irrigation water from the Kennewick, Prosser and Columbia irrigation districts, and to wash thoroughly with soap and warm water if they do to remove potential bacterial contamination.
Redfield-Wilder said the smaller the stream or creek, the larger the concentration of fecal coliform is likely to be.
The ecology department is focusing efforts on cleaning up several smaller waterways in the Yakima Valley from Ellensburg to Benton City.
Officials also are recommending that people use caution when playing in or near the water this summer -- avoid swallowing water from rivers, streams and creeks, and wash hands or shower after coming into contact with water.
Home septic systems and drain fields should be checked at least once every three years and pumped if necessary.
Livestock should be fenced away from streams and given alternative water sources, and pet owners should scoop the poop into a plastic bag and throw the sealed bag into the garbage.
Perkins also recommended not swimming or fishing downstream from any kind of drainage, such as from agriculture.
"We don't want to scare people away from enjoying recreational activities," Perkins said. "We just want them to be aware of it."
-- Michelle Dupler: 509-582-1543; firstname.lastname@example.org