Sewer System Maintenance & Operations Manager Mike Zapior took us for a tour of a 121-year-old stretch of sewer 25 feet under Cleveland over the summer. He walked and talked about the history of the pipe, how it was designed to protect the system, and how it’s better when it doesn’t have to be used at all.
The pipe dating back to 1898 is a combined sewer outfall, a relief structure that prevents sewage and stormwater from overwhelming the system during heavy rain events. The combined sewer design is the foundation upon which Cleveland was built as it successfully captured sewage and stormwater for transport and eventually treatment.
As the region’s population grew and hard surfaces increased, combined sewers began receiving larger volumes of stormwater runoff at much faster rates, leading to frequent overflows at these outfall locations. “The system was designed to have these overflows,” Zapior explained, to protect property and infrastructure back in the day. But it proved to be not good for public health or the environment.
In the 1970s, combined sewers overflowed to the tune of 9 billion gallons a year. Our work from 1972 through the 1990s cut that number in half, and by 2036, that number will drop by another 4 billion gallons a year thanks to Project Clean Lake.
For perspective of how the system has improved to reduce overflows over recent decades, consider that this Edgewater Beach location used to discharge as many as 50 times a year back in the 1970s; in the last five years, it has discharged a total of five times.
Our goal is to reduce that number even further. Across our service area, there are more than 100 such outfalls, and the frequency of overflows decreases with every new Project Clean Lake sewer that goes online. Some outfalls will be eliminated completely.
Video by Senior Communications Specialist Michael Uva.