GID, GFLD have water
July 17 marked the one-year anniversary of an event many in Goshen County and nearby Scotts Bluff County in Nebraska will never forget – the collapse of Goshen Irrigation District (GID) and Gering-Fort Laramie Irrigation District’s (GFLD) tunnel number two, west of Lingle.
The startling event caused a large breach of the canal wall and dried up water for 42 days during a critical point in the growing season, affecting over 107,000 acres in the North Platte River Valley of Wyoming and Nebraska.
Following the collapse, Gov. Mark Gordon declared a state of emergency and stakeholders in the area worked day and night to find a way to get their water back. They decided on a temporary fix, which could assist in a permanent fix later on, in order to catch the last few weeks of water for the 2019 growing season.
The collapse of tunnel number two was eye-opening in regards to the amount of old irrigation infrastructure across the state of Wyoming. Therefore, GID and GFLD performed maintenance and repairs on all three of the irrigation tunnels in their districts.
“Temporary repairs to the three tunnels on the main canal had to be completed before water could be delivered this season. But the water is flowing to the farmers,” states University of Nebraska-Lincoln (UNL) Extension.
UNL Extension notes repairs to tunnels one and two have been completed with the installation of approximately 60 steel ribs and grouting inside each tunnel.
“Permanent repairs to these two tunnels should be completed by the end of 2022, including the permeation grouting and removal of most of the steel ribs from both tunnels,” UNL says. “The ribs in tunnel number two will remain in place near the collapse site.”
In addition, UNL Extension notes repairs to tunnel number three have been completed, including installation of steel ribs and grouting.
“The only remaining repair item is the installation of cathodic protection for the steel ribs, a technique used to control corrosion,” UNL explains. “This will take place at the end of the 2020 growing season.”
Although water is flowing, the installation of the steel ribs has caused water flow through the tunnels to be reduced.
GID estimates total water flow through tunnels one and two will be reduced to 80 to 85 percent of full capacity.
“Water flow through these tunnels is approximately 1,200 cubic feet per second or 19,020,000 gallons per minute,” GID states.
For growers on the North Platte, reduced water flow means reduced water deliveries. In fact, the GFLD says it is planning for their irrigators to receive only 75 percent of their normal allotment.
“By starting the irrigation water in the canal earlier and planning to run later in the season, it is hoped this will lessen demand during peak water demand in July and August,” says GFLD. “When final repairs to tunnels one and two are completed and the removal of most of the steel ribs is done, water flow volume should return to near normal.”
Hannah Bugas is the managing editor for the Wyoming Livestock Roundup. Send comments on this article to firstname.lastname@example.org