How Does Manhole Rehabilitation Benefit Communities And Budgets?

If corrosion and infiltration issues are affecting your wastewater system, you have likely spent many hours combing through budgets and researching options. Fortunately, advancements in spray-applied polyurea lining systems mean that there are effective and affordable options for even the most daunting sewer repair projects.

OBIC sewer lining repair systems are proven effective and have a faster return on investment than other options on the market. To illustrate the benefits of OBIC, we compiled an example of the impact one manhole rehabilitation can have on a small to medium-sized municipality.

OBIC manhole rehab case study

A municipality has one leaking manhole with groundwater infiltration. The manhole is 9’ deep and is leaking 2 gallons of groundwater per minute. Although that may not seem like a lot, the impact quickly multiplies.

2 gallons/minute x 1,440 minutes/day x 365 days/year = 1,051,200 gallons per year

The average cost to treat 1,000 gallons of wastewater is $1.75. With groundwater leaking into the wastewater system, that is a lot of money going down the drain.

1,051,200 gallons/year ÷ 1,000 x $1.75 = $1,839.60

If the municipality were to leave the leaking manhole unaddressed, they would spend approximately $1,839.60 treating groundwater unnecessarily. As the leak continues to worsen, that number will continue to climb. This also increases the risk of a sanitary sewer overflow.

The average cost for manhole rehabilitation using the OBIC Armor manhole lining system is $2,250. In less than 1 year and 3 months, the OBIC Armor manhole lining will have paid for itself and continued to save the municipality the cost of treating the groundwater.

$2,250 ÷ $1,839.60 = approximately 1.2

Since it is unlikely that only one manhole in the system is experiencing groundwater infiltration, OBIC recommends that small to medium-sized municipal system owners select 10 manhole rehabilitation projects to complete in a year. Each manhole chosen should have a 2 gallon per minute leak or more. Those 10 manholes are then repaired with OBIC the Armor manhole lining system at an approximate cost of $22,500. This reduces the amount of groundwater being treated by over 10.5 million gallons per year and results in a return on investment in approximately 15 months.

Benefits beyond dollars and cents

Overburdened water and wastewater systems have a direct impact on the budget, but they also have an unintended impact on growth opportunities. If, for example, a community wants to build a new home development the wastewater treatment plant must be able to accommodate that growth. A treatment plant that is overburdened by 10 manholes leaking 10.5 million gallons of groundwater is already falling behind. Without corrective action or a 10-million-dollar expansion, that housing development will not be possible.

How does manhole rehabilitation help solve this problem? Taking a look at the math once again, the average four-person home in America uses an average of 350 gallons of water per day.

350 gallons x 365 days = 127,750 gallons /year

Rehabilitating 10 manholes with OBIC Armor manhole lining will eliminate enough groundwater to allow 82 new homes to be connected to the system.

10.5 million gallons ÷ 127,750 = 82 homes

To learn more about how OBIC manhole lining systems, visit our website and request an on-site demonstration at