(Okoboji)– A broken sewer main sent an unknown amount of raw sewage into West Lake Okoboji over the weekend.
The Iowa Department of Natural Resources says crews with the Iowa Great Lakes Sanitary Sewer District discovered the break on the southeast side of the lake around 11:30 yesterday (Mon.) morning. Officials say the wastewater was discharging into a culvert that runs under a street and into a grass waterway. It then goes into a ravine and flows about a quarter of a mile to the lake.
The break was discovered at a resident reported hearing running water in the area.
A DNR environmental specialist says it appears wastewater had been discharging already for a few days at an estimated rate of 35 gallons per minute until about 2:30 p.m. yesterday (Mon.). That’s when crews with the Iowa Great Lakes Sanitary District began pumping and hauling the wastewater to the treatment plant.
Officials say a small amount of wastewater continues to bypass into the lake.
DNR Environmental Specialist Bryon Whiting says people should keep children and pets away from the shoreline and out of the water for the next 48 hours in the Wheelers Woods area. Whiting says those who plan to swim at Terrace Park Beach should be aware that bacteria counts could be elevated for the next 48 hours and should use their own discretion.
DNR staff took water samples near the discharge to test for bacteria and other pollutants. They also notified residents who live in the immediate area.
The DNR has also notified three drinking water plants that draw water from the lake, including Milford Municipal Utilities, Central Water (which serves Arnolds Park and Okoboji) and the city of Wahpeton. DNR officials say normal water treatment processes at the plants should adequately protect drinking water.
