Northeast Ohio Regional Sewer District

When you flush your toilet, where does it go? The collection system is a complicated series of sewers, force mains, manholes, regulators and lift stations. Proper maintenance of the collection system ensures that wastewater is not allowed to back up and overflow into the street, someone's home, or into the streams, rivers or Lake Erie. Sewage enters the collection system from a variety of sources: residential customers, industrial customers, and stormwater. Residential or domestic wastewater is sewage that is derived mostly from homes, businesses, institutions, and more, originating as wastes from kitchens, bathrooms and showers.

Cleveland's earliest sewers are "combined sewers" that carry sanitary sewage (from your house), stormwater (from rain and melted snow), and industrial waste in a single pipe. When indoor plumbing was first developed, the pipes from residences were fed into the original storm sewers, which would empty raw sewage directly into area streams and Lake Erie. Thankfully, treatment plants were built in the 1910s and 1920s to clean the dirty water before it enters the environment. When heavy storms produce large volumes of surface runoff, combined sewers may not be able to handle the increase.