The Washington State Department of Ecology is fining the city of Snoqualmie for alleged violations at the Snoqualmie wastewater treatment plant.

The city is reviewing the matter and seeking relief from the fine.

The Ecology department hit the city with a $24,500 fine for allowing its wastewater plant to violate standards over a three-month period last winter.

According to its report, the department was not promptly notified about a series of problems that began in December 2008 and continued into February 2009.

The system failed to meet standards for three kinds of pollutants in the plant’s water-quality permit, resulting in 21 permit-standards violations during that period.

The plant discharged water that violated standards for fecal coliform bacteria, total suspended solids and biological oxygen demand.

Bacteria levels indicate how well the wastewater was disinfected. Total suspended solids is a measurement of solid matter, which can harm fish by damaging their gills. Biological oxygen demand is a gauge of the amount of oxygen consumed in the environment by the treated water. This reduces the amount of oxygen available in the river for fish and other aquatic life.

Kevin Fitzpatrick, Ecology’s regional water quality program supervisor, said that when the state learned about the violations, it took only hours to come up with a temporary fix.

“There was no reason for these violations to continue,” Fitzpatrick said.

The process involved chemical treatments to separate water from the solids. Liquid was pumped to the treatment plant, where it interfered with a treatment stage that produces clear water. This, in turn, decreased the effectiveness of a disinfection system that shines ultraviolet light into the treated water.

Ecology’s investigation also found that key parts of the treatment system had gone without proper maintenance. The disinfection system lacked several ultraviolet bulbs, and pumps needed at two critical treatment process stages were not working properly.

Ecology ordered the city in February to substitute chlorine treatment to disinfect the wastewater, until the other problems could be corrected. The plant returned to ultraviolet disinfection by mid-March, while keeping chlorine available in case problems return.

The lagoon decommissioning project is complete and the city’s plant effluent quality is currently meeting all requirements set by the state, according to Joan Pliego, city communications coordinator.