Challenges and Combined Sewer Overflows

By Ryan Connair

sewer overflowing

Overflows happen when combined sewers are overwhelmed by heavy rain.

Every year, combined sewer overflows (CSOs) release about 850 billion gallons of untreated sewage and stormwater into lakes, streams, and rivers across the United States. CSOs happen when combined sewers—which carry both stormwater and raw sewage—are overwhelmed by heavy rain and flow into local waterways.

Unfortunately, this situation is hard to fix. Sewer utilities have thousands of miles of pipes to manage, so they often lack the resources to continuously monitor CSO activity or precisely measure how much wastewater is being discharged into the environment.  A low-cost, wireless sensor could change all that, though.

To find such a sensor, EPA partnered with Confluence—a water technology cluster in the southwest Ohio, northern Kentucky, and southeast Indiana area—to issue an open innovation challenge. Open innovation challenges offer awards for solutions that address a problem and draw in the best ideas from around the world.

The challenge was issued in July 2013 through Cincinnati Innovates and InnoCentive, who recently announced the winners.

First prize of $6,000 was awarded to Krishna Priya, from India, with prizes of $2,000 each going to Tamus Szalay (USA) and Andre Villemaire (Canada). Priya’s winning solution combined water level and ultrasonic sensors with a cellphone radio to create a prototype device that monitors water level and flow. During a CSO event, the system can send data back to utilities via text message.

“Real-time information provides the ability to plan for the events, respond quickly to equipment malfunction, and assure control systems are operating properly,” said Melissa Gatterdam, Superintendent of Watershed Operations at the Metropolitan Sewer District of Greater Cincinnati (MSDGC).

But the challenge goes beyond identifying a winning idea, it also involves a community. In this case, the community is Greater Cincinnati. Two local utilities—MSDGC and Sanitation District No. 1 of Northern Kentucky (SD1)—and a local branch of the technical consulting firm Stantec provided judges for the contest. The two utilities have expressed interest in testing the prize-winning ideas identified by the competition.

“EPA has displayed exceptional leadership with this challenge, which has catalyzed the difficult process of transferring new ideas into new technologies that are ready for the marketplace,” said Chris Kaeff, Regulatory Reporting and Wet Weather Coordinator for SD1.

“The public utility stands to gain new technology that improves operational efficiency,” Kaeff said. “The entrepreneur gains a pathway to impact the market. The venture capitalist gains an opportunity for investment. And the federal regulatory and research agency moves closer to its goal of ensuring compliance.”

Partnering to issue the challenge, EPA was able to accomplish two goals: the challenge identified a solution to a pressing environmental issue and connected the winners to utilities who can put their ideas into practice by serving as test beds for the technology and potential buyers in the market for the finished solution.

About the author: Ryan Connair works with EPA’s Environmental Technology Innovation Clusters Program as a communications contractor.

Editor’s Note:

Read more about EPA research exploring ways to reduce stormwater runoff and combined sewer overflows:

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