This past weekend untreated wastewater poured into the West Okoboji Lake. The contamination was caused by a break in a force main. It’s believed the wastewater flowed for multiple days, but the Department of Natural Resources reports that a resident’s actions saved the lake from even greater pollution:
After a report from a resident who heard water running, staff from the Iowa Great Lakes Sanitary Sewer District investigated and found untreated wastewater discharging into a culvert. The culvert runs under the street and into a grass waterway. Then it runs into a ravine where the wastewater is diluted with surface water as it flows about one-fourth mile to the lake.
“We appreciate when residents notice and report unusual things,” said Bryon Whiting, a DNR environmental specialist. “Due to the location of this break, the bypass could have occurred for much longer. People need to report these types of observations.”
Staff from the DNR estimate about 35 gallons per minute of wastewater was being released until about 2:30 p.m. Monday. At that time, the sanitary district began pumping and hauling wastewater to the treatment plant. A small amount of wastewater continues to bypass.
The DNR is preaches caution to local beach goers and water plants.
Whiting said 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. Also, people 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 of the discharge.
The DNR has notified the three drinking water plants which draw water from the lake so they can protect their water systems: Milford Municipal Utilities, Central and Wahpeton water supplies. Normal water treatment processes at these plants should adequately protect residents’ drinking water.