So, let’s talk about sewers! Did you know that sewer systems were originally designed to include both rainwater and sewage? The idea was that the occasional rainstorm would flush the combined sewer system allowing its performance to be maintained, before sewage treatment plants (STPs) were required. Then, as STPs were added to remove the harmful bacteria, oils & greases and other unmentionables that we flush down the drain, the hydraulic capacities of such systems had to be designed without precipitation flows because otherwise such facilities would need to be several times larger – and far more expensive. Thus, combined sewer overflows (CSOs) occurred – necessarily: As the lesser of evils, diluted large volume flows during rain events had to bypass the STP due to capacity limitations.
Intentionally bypassing treatment is a serious matter of course. With pressure from the United States Environmental Protection Agency (EPA) and the Department of Justice (DOJ), cities scrambled to address this. State environmental agencies have the primary authority to resolve these matters, but EPA and DOJ have demonstrated that they often value notches on the gun more than cost-effective environmental performance. As a result, many “Consent” Decrees (CDs) were developed but the Feds are typically unwilling to re-open the CDs even though Long Term Control Plans (LTCPs) that are required as part of the CDs always benefit from re-evaluation and mid-course corrections. To develop these CDs, every major city in America began “offering” stopgap solutions encouraged by EPA/DOJ, including massive underground tunnels to be built to temporarily store CSO flows – until those flows could be safely treated. All of this had resulted in cities who had done nothing wrong to cause the problem.
As tragically bad all of this has been, there is now another option and its colossal success has been demonstrated – it’s a Do-over! The City of South Bend, Indiana, its (then) mayor, Pete Buttigieg, and his technical team accomplished this (with our assistance and our recipe). The City obtained a Do-Over, substantially revised its Consent Decree and its LTCP and now operates a smart sewer system with 165 sewer sensors, 13 automated gates and impressive software; and no massive tunnels. This system is saving the city’s taxpayers many hundreds of millions of dollars. During rain events, the software optimizes flow paths for maximum environmental protection and does so more effectively than the far-more-expensive infrastructure virtually required by the Feds in all CDs.
What is preventing replication of this smart sewer system in every major city in America – a system that achieves environmental results more quickly with potential overall savings to the U.S. of at least $500 billion dollars? Answer – NOTHING. All you need is the recipe for a Do-Over using the latest version of smart sewer systems and someone to ensure that all remain steadfast to the recipe – (including your team) which is more difficult than you may imagine. There is no need to re-create the wheel. Precedent is established and clearly should be replicated – everywhere!