Last year, city crews repaired 112 manholes.

That might seem like an insignificant administrative detail, but it’s more important than it seems on the surface.

A major report on the state of Bentonville’s sewer system, released about a year ago, identified two main problems:

Upsizing the pipes is incredibly expensive, which is why the city is taking out a $239 million line of credit from the Alice L. Walton Foundation.

The excess stormwater issue is, in comparison, much easier and cheaper to address.

The report estimates that spending about $3.5 million to fix the most pressing issues could meaningfully reduce excess stormwater during major rain events.

The City Council allotted $2 million for stormwater-related repairs last year and $2 million for 2026, according to Beau Thompson, deputy director of Bentonville’s water utility.

Hearing that the sewer system is “at capacity” might conjure up an image of pipes being completely full, ready to bust at any moment.

However, that’s not the case. State health officials require systems to be designed so pipes are only about 25% full on an average day, leaving room for events that strain the system.

One of those events that capacity is reserved for? Big storms.

There’s no need for rainwater to enter the sewer system (the one that takes your poo when you flush a toilet) as there’s no need for it to be treated by the sewage treatment plant.

Instead, stormwater is directed to the drains you see in curbs — the kind where the clown lives in “IT” — before traveling through a decentralized system that carries it to drainage ponds and creeks.

Infrastructure experts expect that some amount of water will get into a sewer system during storms. However, in Bentonville, that leakage is excessive.

So how does stormwater get into the system?

The biggest offenders are uncapped sewer cleanouts at businesses and homes, flawed manholes, and defects in sewer lines.

As part of research into sewer conditions, contractors put colored smoke into sewer lines to identify leaks. That helped identify 116 uncapped sewer cleanouts at homes and businesses.

A sewer cleanout connects directly to a building's sewer line, giving access to clear clogs or inspect the system. When the cap is missing or damaged, it can act like a funnel during storms, allowing rainwater to flow straight into the sewer system.

It's easy for the cap to come off — lawnmowers nicking them is common. It's also cheap and easy to fix.

For known sewer cleanout issues, the city has mailed those residents and businesses asking them to make repairs.

Inspectors also flagged 653 manholes with defects that let stormwater in. Together, those manholes are estimated to leak about 328 gallons per minute into the sewer system during a heavy storm — the equivalent of flushing a toilet more than 200 times every minute.

Cracked or damaged sewer lines can also let stormwater seep in. These days, pipes are mostly made of PVC or concrete. However, many older lines still in the ground are made of clay, and some have small cracks that allow water in under pressure.

“Most of ours are cracked in, like spider webs. So when you get so much rain that there's so much pressure on it from the additional weight of the water it can push through those spiderwebs cracks,” Thompson said.

While some might need to be replaced, there's another method that allows a new liner to be installed without any digging.

"We can blow in a liner, line that sewer pipe, and we don't have the additional cost of rebuilding the road or rebuilding the sidewalk or putting back a yard," Thompson said.