Cascade County Commissioners approved an agreement with the Montana Department of Transportation for repairs to North River Road.

The section of road from the intersection with 10th Street North extending east along the northside of the River’s Edge Trail has been closed since September due to a failed storm drain.

The project will replace about 130 feet of the failed 30-inch drain pipe.

Les Payne, county public works director, said that MDT is handling the repair project and the county’s responsibility is to maintain the road closure barricades while the repairs are completed and to reopen the road to the public when the project is complete.

MDT seeking public comment on North River Road storm drain repairs

The county is responsible for maintaining North River Road and will continue to do so once the repair project is complete, according to the agreement. Payne said the county will likely stripe the road when the repair is complete.

In September, city employees found two sinkholes along the existing storm drain culvert and notified MDT and the county.

MDT’s project will fill the visible sinkhole areas, abandon the 30-inch culvert, provide a drainage solution and restore traffic to the road and River’s Edge Trail.

Payne said the project will redirect the failed culver to another one, pull out the exposed culvert and fill that void and fill the portion that goes under the trail with concrete.

He said a culvert won’t be placed in the same spot again.

Payne said the project was scheduled to go out to bid this month, and MDT said construction is planned for 2025 depending on completion of design and availability of funds.

Portion of River’s Edge Trail reopens, North River Road remains closed [2024]

James Combs, the Great Falls district preconstruction engineer for MDT, told The Electric in January that the agency was using state funds for the project.

Combs told The Electric that the project intent is to remove the culvert across North River Road and fill and abandon the culvert south of the roadway towards the outfall.

Construction activity shouldn’t affect the River’s Edge Trail, Combs said, other than whatever access the contractor needs to place a bulkhead at the outfall.

North River Road remains closed, River’s Edge Trail to reopen next week [2024]

Combs said MDT has assumed the work of abandoning the failed storm drain as the collective storm drain system manages stormwater runoff primarily for the road system is maintained by MDT.

Right-of-way acquisition or temporary construction permits are not anticipated. Relocation of utilities may be necessary. Landowners may be contacted prior to construction regarding temporary permits.

The portion of the River’s Edge Trail that closed in late September reopened to pedestrian traffic in November after temporary repairs to a storm drain break were completed.

Portion of North River Road closed indefinitely [2024]

In late September, Cascade County public works alerted the public to the road closure.

The city issued a release a week later regarding the trail closure, which had been confirmed to The Electric by city staff days prior.

In late October, The Electric followed up with city, county and MDT officials about the closure.

On Oct. 29, Jim Wingerter, Great Falls district administrator for the Montana Department of Transportation, told The Electric that his office was researching documents and agreements to determine ownership and responsibility for the storm drain.

The road and trail were closed Sept. 23 due to sinkholes near North River Road, one between the Missouri River and the River’s Edge Trail just east of the old 9th Street bridge, the other behind the curb radius at the intersection of North River Road and 10th Street Northeast, Payne told The Electric in October.

MDT is taking the lead to expedite materials and repairs, Wingerter said in the fall, and the failed storm drain impacts MDT, the City of Great Falls and Cascade County.

The storm drain pipe is located about 8 to 10 feet below the ground surface and has been corroding for a long period of time, degrading the pipe structure, causing storm water runoff to erode the surrounding soils, Wingerter told The Electric.

City approves next phase of river bank stabilization project

The erosion created a void, causing the two sinkholes, Wingerter said, and there was no indication of the drain pipe failure or the voids until the sinkholes appeared and were noticed by city staff on Sept. 23.

There’s been no damage to the road or trail at this point and both were closed as soon as the sinkholes were discovered for safety reasons.

The void under the River’s Edge Trail was filled, Wingerter said in the fall.