MOSES LAKE — Most of Moses Lake is safe for boating and irrigating after a sewage spill prompted a seven-day no contact health advisory last week, according to information provided by the Grant County Health District on Friday.
The newest lake samples taken this week showed most of the affected areas had improved. However, the Health District is recommending people stay out of lake waters at Blue Heron Park until test results are known, said Health District Administrator Theresa Adkinson.
The state Department of Ecology is recommending the City to conduct tests upstream and downstream and those results will inform the Health District.
Test results at the spill site were at acceptable levels.
The Health District is not extending the no contact advisory until it receives more test information.
Beyond Blue Heron Park, blue green algae levels are still high in Moses Lake. Swimming is not recommended.
The cause of the sewage spill was a baseball-sized hole in the aging Knolls Vista siphon. City wastewater employees installed a stainless-steel band to stop the discharge. From the time of notification at 6:20 p.m., on Aug. 28, to the time of repair at 11:30 p.m., city staff estimates about 64,000 gallons of raw sewage was discharged into the lake.
Due to the age and recent history of damages to the Knolls Vista siphon, the City is making immediate upgrades to the collection system in the Knolls Vista and Sage Bay tributaries. A preliminary design meeting with the City Engineering Division was held on Wednesday.
Once finalized, the upgrades start with bypassing the Knolls Vista siphon by installing a gravity main directly to Sage Bay Lift Station. Sage Bay Lift Station has the capacity for additional flows. The second phase of the project includes the installation of a forced main to the existing main, connecting downstream of Sage Bay Lift Station. During the final stage, a parallel force main will be added from Sage Bay Lift Station across the lake. The force main allows for emergencies and increases the flow capacity.
For more information on the health impact contact the Grant County Health District at 509-766-7960. For additional information about the spill contact the City of Moses Lake’s Municipal Services Department at 509-764-3783.
City of Moses Lake: Lynne Lynch, 509-764-3706, email@example.com.
Grant County Health District: Theresa Adkinson, 509-766-7960, ex. 24, firstname.lastname@example.org