Montana Department of Transportation crews worked throughout the week to repair a 75-foot long sinkhole caused by a failed irrigation pipe just east of Delaney’s Landscape Center on Montana Highway 35.

The hole was discovered this past Wednesday during a routine maintenance check by MDT crews. The eastbound lane around the hole has been closed since its discovery, with traffic being rerouted through the turning lane. Westbound traffic has so far been unaffected.

It took crews into Wednesday afternoon to find the cause of the sinkhole, as they waited for irrigation water pipe water to be shut down.

MDT communication director Charity Watt-Levis confirmed on Friday the crews had found a burst irrigation pipe under the hole.

“All the materials under it were saturated and that causes the road to sink,”  said.

The sinkhole was estimated to be 12-feet wide, 4 feet deep and 75 feet long. Crews opened the crevice must wider as they dug through the pavement around the hole to survey damage and make repairs.

By Friday, repairs had been made and crews had poured concrete around the irrigation pipes. Traffic would remain only slightly interrupted throughout the weekend until crews can pave the spot next week, Watt-Levis said.

Incidents like this aren’t too common, Watt-Levis said, and the department conducts regular inspections throughout the road systems to make sure they remain safe for travel.

The road should be fully operational by mid-week next week. A temporary 35 MPH speed limit has been posted around the construction area.