Heavy rain and the failure of a bypass pump around the sewer lift station on Buena Vista Loop Friday sent approximately 16,000 gallons of contaminated water onto the beach between Chetco Point and the North Jetty of the Chetco River.
The city of Brookings reported the spill to the Oregon Department of Environmental Quality and posted the beach in the area.
The overflow occurred at about 7:30 a.m. when Brookings Police dispatch informed the sewer plant operator on duty that there was an alarm at the Buena Vista Loop lift station, reported Brookings Chief Plant Operator Joe Ingwerson.
The operator responded and found the wet well full from high rainfall and runoff. The operator pushed the reset buttons but observed no change in the water level in the wet well.
A contractor hired to upgrade the Buena Vista Loop station had set up temporary electrical controls for two pumps that were placed in a manhole to bypass the flow around the lift station while they completed the work.
Ingwerson said the pumps could not keep up with the flow of water caused by approximately 1.7 inches of rain in the early morning hours.
To alleviate the situation, city workers put in a high volume portable pump rated at 800 gallons per minute shortly before 9 a.m., he said.
The system had backed up enough to overflow into a residence and the city did not want this to continue, Ingwerson said.
He said the city chose to pump the water out into the bypass line because they didnt have enough pipe to reach the manhole where the pressure main enters.
Total time of pumping at 200 gallons per minute was one hour and 20 minutes, Ingwerson said.
We calculated the bypass volume to be approximately 16,000 gallons, Ingwerson said.
He noted that the water was primarily rain water with only a trace of contaminants. The overflow pipe used empties into a culvert which goes directly into Chetco Cove, Ingwerson said.