More than 100,000 acres of farmland in southeastern Wyoming and the Nebraska panhandle is in jeopardy of going dry after an irrigation tunnel collapsed last week.

The canal, which supplies irrigation water to Goshen County, apparently collapsed early July 17 roughly a mile south of Fort Laramie. The collapse caused water to back up and overflow from the canal upstream of the tunnel, according to a news release.

Goshen County Commissioners on Monday declared a local disaster.

"Goshen County has suffered from an irrigation canal breach, resulting in the loss of irrigation water for over 100,000 acres of farmland," the declaration reads. "Extensive damage was caused to private property and the loss of the irrigation water will result in an extensive loss of agricultural crops to the farmers of Goshen County within the disaster area."

It remains unclear how long the canal will be out-of-service, the Goshen and Gering-Fort Laramie irrigation districts said. Both districts have asked the Bureau of Reclamation to reduce flows out of Guernsey Reservoir.

The canal serves 104,000 acres if Goshen County and Scotts Bluff County, Nebraska. Corn, wheat and sugar beets are some of the main crops grown in the area.