With severe wet weather conditions in NEW Water’s service area last night and continuing into this evening, our community’s shared sanitary sewer system has been inundated with stormwater. At its peak, NEW Water’s system received about 214 million gallons per day; on average, we treat 41 million gallons per day. This is more than 5 times the average flow.
The NEW Water team worked throughout the evening in the treatment facilities and collections system to ensure continuous service to the 15 municipalities we serve in Northeast Wisconsin.
Flooding issues continue in much of the collections system, and the team is working with partners to mitigate impacts.
We’re continuing to monitor weather forecasts and impacts.
This significant increase in flow is not due to people flushing their toilets more – it’s due to inflow and infiltration, or I&I. It is important to note that the sanitary sewer system is not designed to treat “clear water,” or stormwater. Essentially, our community is paying for clean water to be cleaned.
In NEW Water’s service area, unlike in some communities, the sanitary sewers (i.e., the sewers that handle toilet flushes, laundry, dishes) are not connected to storm sewers (i.e., the sewers which move stormwater into area waterways – often seen from grates on roadways). See enclosed image. During wet weather events, the community’s shared sanitary sewer system becomes inundated by I&I, from issues including improper connections to the sanitary sewer through downspouts, sump pumps, foundation drains, or cracks in pipes. During wet weather events, wastewater treatment facilities receive more flow than they are designed to handle. This situation is neither cost effective, nor sustainable. In addition, this additional strain on the sewer system puts your home at risk due to potential basement backups. NEW Water is actively working with municipal partners to address this issue.
Learn more about I&I here, and how you can help >>
Infographic credit: Town of Gilbert, AZ (Minor edits made to graphic)