ELGL’s Best of Water
Building a Smarter Sewer System to Reduce Overflows in Greater Cincinnati
Cincinnati , OH , United States
At a Glance: To keep sewage mixed with stormwater out of waterways during rain events, Metropolitan Sewer District built a smarter sewer system that costs less than any other solution. Using sensors and computers, we can now monitor and redirect stormwater flows from full interceptor sewers to areas with available capacity.
The challenges this project addresses are: Hurricanes & Severe Storms, Stormwater Management, Water Quality, Public Safety
Southwest Ohio experiences over 40 inches of rain in a typical year, and, as is common in an urban environment, long or intense periods of rain can overwhelm the existing infrastructure and overflow into the nearby creeks and rivers. MSD’s collection system contains more than 200 such overflow points. Together these overflows used to discharge over 11 billion gallons of combined flow into the Ohio River and its tributaries during a typical year. In the first year alone, this system cut costs in half and prevented a total of 2.65 billion gallons of overflow (15% more than the facilities would have been able to prevent without the new system). Furthermore, the system virtually eliminated sanitary sewer overflows from the constructed overflows, and we can now prioritize the treatment of high strength wastes from industrial dischargers during certain wet weather conditions. Overall, with real-time monitoring and real-time control capabilities, we have been able to optimize the efficiency of our existing infrastructure.
The Metropolitan Sewer District of Greater Cincinnati used/is using a comprehensive smarter sewer system that helps reduce sewer overflows into our creeks and rivers to address this/these challenge(s).
This technology can dramatically improve City responses to storms, which affects all establishments in the sewer jurisdiction. Over the last two years, MSD has presented its findings at Water Environment Federation conferences numerous times, and was the most widely discussed case study in the Water Research Foundation’s Intelligent Water System Focus Group’s regional workshops and national summit. Upon hearing about what MSD was doing, staff from the USEPA invited MSD to present directly to Office of Water and Office of Enforcement and Compliance Assurance staff. Through two live-cast webinars to 75+ USEPA staff from offices across the country, MSD has share its story of operational optimization, and how “Smart Sewers” have improved wet weather performance at extremely low costs (1 cent/gallon). As word spreads, cities from Chattanooga to Atlanta to Washington, DC are routinely contacting MSD to learn more about this approach. MSD is now considered a leader in finding more affordable ways to achieve compliance.
- Remote monitoring (data collection from the field) costs went from $3.5-4.5M/yr before this system was in place to $2.7 M/yr, while at the same time we have quadrupled the number of monitoring sensors.
- Volume captured (meaning less overflowed into our streams) at 4 specialized water pollution control facilities was increased by 33% from 1.36 billion gallons to 1.81 billion gallons.
- It used to take 3 weeks out of every month to generate a regulatory report for the EPA, now we can produce that report in 1 week.
Local Government Champion: Metropolitan Sewer District of Greater Cincinnati (MSD)
Something Unique: MSD is pioneering the use of Internet of Things (IoT) technology to add additional capacity to existing sewer system, aid stormwater management, and strengthen the City's resilience.
Who should consider? Any urban community that struggles with stormwater management, particularly with respect to sewer overflows.