We're doing something new to help you address one of your most costly problems.
Stopping inflow and infiltration can be expensive. Allowing it to continue can cost even more.
Inflow and infiltration causes serious problems for municipal utilities, furthering degradation of infrastructure, contributing to sewer overflows, and increasing flow to treatment plants, all of which come at a high cost. Preventive maintenance and rehabilitation can be expensive, but proactive utilities can save millions in the long run by taking the necessary steps to keep I&I out of their collections systems.
To help in that effort, we’re launching I&I – Inflow & Infiltration Solutions and Equipment. The new magazine will be a quarterly supplement to Municipal Sewer & Water, featuring case studies, technical columns and how-to stories demonstrating the tools, technology and approaches utilities are using to improve their systems.
A recent Envirosight white paper citing several studies highlights the high cost of inflow and infiltration. One study of all municipal sewer systems in Tennessee conducted by George Kurz, P.E., DEE, found that I&I represents nearly 105 billion gallons per year, accounting for 45 percent of the annual flow to treatment plants. Processing the extra flow is estimated to cost at least $188 million annually statewide, a conservative figure compared to the U.S. EPA’s recommendation for using an O&M rate of $2 to $5 per thousand gallons, which results in a cost estimate of up to $522 million.
It’s such a big issue. So much money is being spent to treat the symptoms rather than cure the underlying cause. But I&I is different from many issues you face. It comes from so many sources and enters collections systems at so many points — manholes, pipe defects, failing laterals, illegal connections — that a simple approach like lining mains won’t solve the problem. Just as that excess flow is likely entering your systems from multiple sources, using multiple techniques to solve the problem is often the best approach.
Regardless of how effective your favorite rehab technique is in solving a specific problem, no single technique can solve all your I&I-related issues. The key is combining techniques, using each where it’s most effective, to tighten up your system and reduce unwanted flow. And before you can do that, you need to understand where it’s coming from so you can develop an effective and efficient systemwide approach.
The content in I&I will be aimed at helping you do just that. We’re striving to bring you the information and insight to make your systems better.
If you have a great story about successfully reducing or eliminating I&I, I’d like to hear about it. One of the great things about MSW is none of you, the readers, are in competition with one another. You all have your own systems, but those systems are part of the larger county, state and national infrastructure. Successful approaches in one utility can be shared and modeled in others to lower cost and improve efficiency, and everyone wins in that scenario.
The first issue of I&I will be mailed with your copy of MSW in October. I sincerely hope you find it helpful in your efforts to improve your systems.
Enjoy this month’s issue.