The Costs of Uneven Manholes

Properly leveling manhole and other utility covers goes a long way toward preventing weather-related problems.

The Costs of Uneven Manholes

Traditional manhole installation presents both performance longevity and worker safety issues.

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When all is working smoothly, underground utilities operate largely undetected by the community. Manholes and other utility covers offer the only visible reminder of these and other critical systems, and most people don’t give them a second thought until they drive over a bad one.

Utility managers are constantly balancing high public expectations (and low awareness of what is involved) with the need to be as cost-effective as possible, while also meeting sustainability goals. Manholes are a potential weak link — and added cost — in all of these areas.

The most obvious, direct costs associated with poorly installed manholes and other utility covers are the labor and material costs of repairing roadways. To avoid these costs, paving crews need to be given the proper tools to make sure manhole leveling is done right the first time and as roads are repaired.

Cities like Longview, Washington, are now including specifications for screw-adjusted technologies like RimRiser that make sure manholes and catch basins are set correctly. The more precisely manholes and other utility covers match the designed pavement elevation, the longer the pavement will last. Proper manhole function also plays a big role in stormwater management and is essential for efficient wastewater systems.

Heavy rains can cause the base around bad manholes to weaken, crack or sink, creating gaps around utility covers and grates and allowing water to seep into manholes and underground utilities.

Ensuring that manholes and other utility covers are as level as possible goes a long way toward preventing weather-related pavement problems. Civil engineers, public works and water managers should include manhole leveling as a strategic part of a city’s sustainability planning, to alleviate frequent and costly future repairs and ensure safer roads that are resilient to the effects of weather.

Equipment damage

There’s also a danger when utility covers are not level with the road’s surface. The National Library of Medicine recently called out poorly installed and maintained manholes as the culprit for unexpected driving hazards on our roadways, especially for motorcycles.

But when these poorly leveled utility covers are hit by city maintenance equipment, such as asphalt laying augers during road construction, street cleaners and snowplows, the cost of repairing these large pieces of equipment is considerable. Raised and tilted manhole covers are particularly vexing and even hazardous for snow removal services.

“In most municipalities you don’t have redundancies in equipment,” says Ray Schwab, a public works civil engineer in the Village of Lombard, Illinois. “If there isn’t another snowplow available or it’s damaged, you’ve lost a plow and perhaps a person’s shift. Depending on resources, you could lose a significant part of your operation — especially in a small community.

“The cost of repairing or replacing a snowplow blade can be as high as $2,000, and that’s not factoring in the added cost to cities and counties when snow removal crews and equipment are sidelined and roads are not plowed in a timely way.”

Worker safety

When it comes to installation and maintenance of manholes, there is a lack of standardized methods and processes, and that can lead to injuries, particularly with less skilled workers on the job. Worker injuries lead to lost time, short-staffed crews and higher insurance costs.

Construction crews installing manholes are using processes that haven’t significantly changed in the last 75 years and which put the safety of essential workers at risk — that is, raising manholes to grade using pry bars and hand-placed shims. This requires multiple people and, in addition to being less precise, manual lifting and shimming with clay or wood (or, too often, whatever is handy) can easily result in crushing injuries.

“Workers have accidents with tools like pry bars frequently and get hit or caught in heavy equipment all the time,” says Beth Stinson, vice president for Education Operations at the American Road & Transportation Builders Association. “If it takes more than one person to do the installation, along with heavy equipment, and tools like pry bars, the chances of an accident go up.”

But there are newer alternatives, like RimRiser bolt- and screw-adjusted leveling systems, that are far more precise, require fewer people to install, and are simpler, faster and safer to use for workers of any skill level. With the current shortages of skilled labor, having a technology that only requires the adjustment of a few screws to level a manhole means crews can get the job done right with fewer people and fewer risks.

“We used to use bricks, wedges or wood shims, but it took a lot more time to set manholes to grade, and in time the bricks and shims would either break down or rot out and the manholes would typically sink,” says David Coffey, wastewater crew leader for the city of Vancouver, Washington. “With RimRiser, I like how quick and easy it is to set to grade simply using a power tool to set it into place. And when we grout the inside, it seals with the sturdy bolts in place, providing a strong base for the castings to sit on.”

Public works managers have an opportunity to design safety into manhole installation and maintenance processes by creating specifications for precise manhole leveling that enhance worker safety, save project costs and result in higher quality, longer lasting and much safer paving around utilities. 

Big impact

Manholes, like the utilities they provide access to, are largely invisible when they’re working well. But they are a significant lever in helping communities be safer, more cost-effective and more sustainable over time. And that can pay dividends in good PR for your public utilities.

And perhaps the most unsung benefit is the pleasant experience of a smooth ride on the roadways of your community – keeping manholes as unnoticeable as they should be. 


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