When she became co-owner of Orlando-based wastewater contractor LRIE, Inc., Karoline Headrick and her business partner decided it was time to transition away from recording inspections by hand.

Manholes are underground assets that allow for easy access to sewer components for cleaning, maintenance and inspection. They are subject to the extreme conditions that all wastewater facilities handle, in addition to weather and traffic stress from the surface. As such, inspecting these necessary access points to ensure their integrity is an important part of collection system maintenance. 

Manholes are vertical underground confined spaces used by utility personnel as a point of access to a sewer system. 

Thank you to the many customers and partners who visited our booth during WEFTEC 2018 in New Orleans last week. We welcomed nearly 300 guests and enjoyed seeing many of our sales partners from across the country. A special thanks to Best Equipment, our sales partner in Indiana, Ohio and Kentucky, for loaning us their new demo truck for the show.

Robert Korosec, PLS, is cofounder of Utica, NY-based Subsurface Utility Imaging (SUI), a company dedicated to location and inspection of underground infrastructure assets since 2010. As such, he’s been actively using and researching new pipeline and manhole inspection solutions on behalf of many municipal clients. “Cities don’t have money, and their infrastructure is unreliable,” he says plainly. “Anything we can do that makes sewer maintenance more cost-effective is useful and appreciated.”

Inspecting sewer lines can help you identify I&I sources and address any problem areas—but that’s not the only inspection you should prioritize. Modern manhole inspections could also save you high treatment costs and expensive regulatory action. Envirosight’s white paper, Rethinking Manhole Inspection: A New Way to Reduce I&I Quickly and Cost-Effectively, outlines why the inspection of manholes can sometimes be more effective than pipeline evaluation and is gaining popularity within the industry.

Manholes are often the biggest source of inflow and infiltration in a sewer system, but aren't always part of routine sewer inspections. Manhole inspections should be included in every utility's inspection practices. Take our Manhole Inspections Quiz to test your knowledge on the subject.

Sewer infrastructure typically runs under streets, so crews who clean, inspect and rehab sewers are routinely faced with traffic hazards as they do their work. The Federal Highway Administration reports that in 2015, a work zone crash occurred once every 5.4 minutes. Taking extra precautions to make these zones compliant with traffic safety regulations is the best way to minimize risk.

Exfiltration is the leakage of wastewater out of a sanitary sewer system through broken or damaged pipes and manholes. Wastewater that leaks out of defective pipe joints and cracks may contaminate ground and surface water and cause a host of other problems, including pipe structure failures due to erosion of soil support, and ground subsidence due to erosion of underground soil. 

Manholes are a critical part of every sewer system as they provide necessary ventilation and an access point for cleaning and inspecting sewer lines. The U.S. Environmental Protection Agency (EPA) estimates that there are about twenty million manholes in the United States—one manhole for every 400 feet of pavement. Many of these manholes are seriously decayed or in need of immediate rehabilitation or replacement.

Manholes generate a disproportionate amount of inflow and infiltration (I&I) and play a unique role in the structural integrity of roadways. From an operational standpoint, excessive groundwater reduces capacity of the collection system as a whole. From a structural standpoint, deterioration and corrosion within a manhole can cause cave-ins (Water World).