During April-May 2018, the NRD measured 542 observation wells throughout the District and then averaged the data of all these wells. Overall, the spring 2018 average measurement for the groundwater level change shows a rise of 0.87 feet from last spring. The findings show that the spring 2018 average groundwater level is 3.89 feet above the “Allocation Trigger.” As a result, there will be no allocation restrictions for the 2019 irrigation season.
The District goal is to hold the average groundwater level at, or above the 1978 level. In 2005, the District average groundwater level reached the “Reporting Trigger” initiating groundwater users to report annual groundwater use to the District and to certify their irrigated acres. If the District average level falls below the 1978 level (“Allocation Trigger”), groundwater allocation will begin.
Observation wells are measured in the spring of each year, allowing the water table to rebound from the previous irrigation season. The observation wells measured are uniformly distributed and represented geographically throughout the District to provide an accurate profile of the District average. Each well measured is assigned an area of the District based on distances to other measured wells. This method of averaging is called the Thiessen
polygon method, and gives the average groundwater level change calculation a weighted average. For more information, please visitwww.upperbigblue.org or call (402) 362-6601.