The Portland Water District is accusing an out-of-state company of using a hydrant without authorization, resulting in a series of water main breaks in South Portland last summer that caused around $150,000 in damage.

The utility announced Tuesday that it is taking legal action against Railroad Weed Control Inc., a vegetation control company with locations in Massachusetts, Ohio and Tennessee, according to its website.

“This is not just illegal — it causes real harm,” Scott Firmin, general manager of Portland Water District, said in the announcement. “Unauthorized hydrant use can damage water mains, reduce fire protection, and jeopardize water quality.”

One of the water main breaks occurred near Broadway just after 4 a.m. on Aug. 26, South Portland police said at the time. The water district said that the break resulted in about 30 customers experiencing low water pressure.

A spokesperson for the water district said Tuesday that the series of breaks last summer spurred $155,000 in estimated damages and that the utility’s board voted Monday night in favor of filing a complaint.

In addition, taking water from a hydrant without a meter is considered theft of services, according to Maine law, and could result in criminal charges, the water district said.

RWC Inc. did not respond to an email request for comment Tuesday evening, and did not answer calls to its Massachusetts location and Ohio office.

According to a draft of the complaint, RWC Inc. “employees or agents” took water from a hydrant on Rigby Road in South Portland “on several occasions” in August 2025 without authorization.

The complaint accuses RWC Inc. of negligence and civil liability for wrongfully obtaining utility services and damages to utility property.

When hydrants are opened improperly, sudden changes in water pressure — known as a “water hammer” — can occur and lead to ruptured pipes and other damage, the water district said in its announcement. The utility also said it can reduce the water pressure needed for firefighting and increase the risk of contaminating drinking water.

The complaint argues that RWC Inc.’s unauthorized operation of the hydrant caused a water hammer. It says the water district “incurred substantial costs” to repair damage to the water main as well as impacted roads and property.

In addition to compensation for damages, the water district is pursuing civil penalties of up to $3,000 for each time the company used the hydrant without authorization and compensation for the water used, plus 5% interest, according to the complaint.

The Portland Water District is also seeking to have its legal fees and costs associated with the investigation into the water main break covered.