Ecology report assesses health of Palouse waterways

MOSCOW, Idaho – Some of the Palouse’s main bodies of water are contaminated by fecal coliform bacteria and plagued by acidity, increased temperatures and a lack of oxygen, according to a report from the Washington state Department of Ecology.

Some major waterways listed by the department include the Palouse River, which runs through Colfax and Palouse, the South Fork of the Palouse River, which splits from the Palouse River in Colfax and runs through Pullman, and Paradise Creek, a distributary of the Palouse River that connects Pullman and Moscow. Many other distributaries of these waterways and portions of the lower Snake River are also contaminated by the same factors.

Brook Beeler, an official at the Department of Ecology’s eastern regional office, said there is no one contaminant that stands out.

The Palouse River, the South Fork of the Palouse River and Paradise Creek are all contaminated by fecal coliform bacteria. Beeler said it’s not an issue of dumping manure into the streams, but rather how livestock are managed.

Beeler said it’s important to keep manure well away from water sources because rain can sweep bacteria into waterways. Livestock’s access to water is another likely source for fecal coliform bacteria in streams on the Palouse, he said.

According to the Department of Health, other disease-causing organisms may also be present where fecal coliform is located and the bacteria may help transmit disease. Drinking or swallowing water contaminated with the bacteria can cause cramps or diarrhea.

Nutrients like phosphorus and nitrogen distributed from wastewater treatment plants into streams can increase vegetation in the water. Beeler said eventually plants like algae don’t get enough light, then die and decompose, a process which in turn depletes oxygen from the water and harms fish and other organisms. When the decomposition phase occurs, carbon dioxide is released into the water and the acidity in the water increases, changing the pH and discomforting the aquatic life in the area, he said.

The Department of Ecology is working with local conservation districts to clean these streams and plant riparian vegetation.