CHEYENNE, Wyo. – Following data collection and review, a public hearing, and receipt of public comment, State Engineer Pat Tyrrell issued an order Wednesday, May 31 that will modify groundwater use limitations for the next three years in the LaGrange area. The First Amended Order modifies the terms of an Order issued on July 19, 2013, in accordance with the terms of that previous Order.
More specifically, the order was issued for the LaGrange Aquifer and surface water diversions from Horse Creek at and below the Brown and LaGrange diversion in southern Goshen County, Wyoming. In crafting the First Amended order, Tyrrell took into account groundwater and surface water use information gained in the first three years of operating under the original Order, as well as comments received from area water users, as expressed at a public hearing in LaGrange on Feb. 15, 2017, and the 30-day comment period that followed.
Notably, according to Tyrrell, groundwater production in the first three years under the original order was significantly below the amount believed to be sustainable under the current level of knowledge. Partly, this was due to favorable hydrology, and to modifications some operators made to their operations. In the last three years there have been no calls for surface water regulation, and Hawk Springs Reservoir has filled every year.
“Only about 48 percent of the allotted groundwater was pumped in the first three years. So, we’ve underutilized the LaGrange Aquifer in some ways,” said Tyrrell. “Those who would benefit from a larger cap should be able to do so, and we can do that, I believe, without jeopardizing the resource in the meantime.”
In the new order, Tyrrell continues the original Order’s closure of the area to further permitting of large capacity wells, and continued the requirement of the adjudication of currently unadjudicated groundwater permits prior to use. However, the First Amended Order increases the allowable groundwater used for irrigation from the LaGrange Aquifer from 12 inches per year (36 inches for the 3-year period) in the original order to a total of 45 inches for the next three water years (starting in water year 2017), with no more than 20 inches produced in any one year. All groundwater wells permitted for over 25 gallons per minute will also be required to continue to have flow meters installed, and to report their use annually. While so limited, groundwater use will not be vulnerable to calls for regulation from surface water rights.
Surface water diversions, and reservoirs, will still be required to have acceptable control and measurement capabilities. Similarly, those diversions seeking to divert water during the winter will be required to have acceptable control and measurement capabilities prior to diverting in the winter, and any such diversions will be required to be spread across the appropriate permitted (or adjudicated) acres up to the soil holding capacity only.
The First Amended Order is in effect for a period of three years, (water years 2017-2019) after which these conjunctive management measures will be reassessed. The current order continues to focus largely on water use data acquisition. At that time, the current order will either remain in effect or be terminated, a new order will be issued, or the order will be replaced by an agreement among the affected appropriators. The order will be posted on the State Engineer’s website.