A permanent solution to fix a damaged irrigation tunnel in southeast Wyoming has been found, according to the Goshen Irrigation District.
Crews will further stabilize the tunnel with ribbing supports and grouting ahead of next year’s water season to ensure the structure will hold next year. Then a chemical grouting process will stabilize and harden the outside of the tunnel permanently, according to an announcement from the district.
In mid-July, one of three concrete tunnels in the Fort Laramie Canal system collapsed, blocking water from moving through the system and getting to farmers, while flooding a few nearby plots of land. It took a month and a half and about $4 million to get the Goshen County tunnel operational again and restore water to the 110,000 acres of farmland between eastern Wyoming and the Nebraska panhandle reliant on the irrigation system.
But the $4 million fix was only temporary, and officials have been working for months to find a long-term repair option for the collapsed tunnel.
The costs for that project will be shared between the Goshen Irrigation District in Goshen County, and the Gering-Ft. Laramie Irrigation District in Scotts Bluff County, Nebraska.
The solution the irrigation districts have decided on is expected to cost about $6 million, according to the Goshen Irrigation District Board Chair Robert Coxbill. But he said the price tag could reach $15 million depending on construction uncertainties.
“It’s an open checkbook,” he said.
You have free articles remaining.
But even at $15 million, it’s far cheaper than some of the initial cost estimates to repair the tunnel. Immediately after the short-term fix was finalized, officials began reviewing options to stabilize the tunnel for the long term. One idea was to sleeve the tunnel with a steel tube. The other was to dig a ditch and abandon the tunnel altogether.
Both of those solutions had originally been estimated to cost more than $60 million. Coxbill said the estimates came from the U.S. Bureau of Reclamation.
The Bureau owns the three tunnels in the system, each of which are more than 100 years old. But the irrigation districts are responsible for maintaining and operating the tunnels.
Before deciding on this solution, the districts paid the bureau $60,000 to compile a report detailing a list of alternative repair options and cost estimates. The bureau provided the districts a report with 10 alternative repair solutions. That report was classified as “controlled,” and when the districts received the report at the beginning of October, they were told not to give the information to press or outside entities.
Still, the information in the report was presented to land owners in the irrigation districts. The Star-Tribune did obtain a copy of the report, but the cost estimates and most of the details pertaining to the alternative solutions were redacted.
The grouting solution the districts ultimately decided on was the solution recommended by the bureau at the report’s conclusion.
“The only solution which could restore original flow in a reasonable amount of time (while the canal is off) is the grouting solution,” that report reads.
Interim repair work is already underway, Rob Posten, the Goshen Irrigation District’s manager, said in the announcement.
The districts will also stabilize one other tunnel in the system that was found to need repair work as well, according to the announcement.
Officials have previously told the Star-Tribune that to pay for this fix, water rates will increase. Officials have also said they plan to look for help from state grant and loan accounts.
Follow local government reporter Morgan Hughes on Twitter @morganhwrites