Developing Consumptive Water Use Maps
To Improve Water Management
Using METRIC™ Remote Sensing Technology
The use of ground water, especially for irrigation, is becominng regulated in Nebraska, in response to several factors:
- Recurrent droughts across the High Plains and Inter-Mountain West have magnified the problem of declining ground water resources. The High Plains Aquifer (HPA), often referred to as the Ogallala aquifer, underlies Nebraska, Colorado, Kansas, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Nearly 30 percent of the ground water used for irrigation in the United States is extracted from the HPA. A significant proportion of the aquifer underlies Nebraska. In the North Platte Basin, the drought has resulted in reduced surface water deliveries, which in turn has led to less ground water recharge and declining water tables.
- Nebraska ground water law has evolved. Ground water levels began declining in some parts of Nebraska after extensive irrigation development began in the 1960s. LB108 in 1996 recognized the relationship between ground and surface water, and LB962 (2004) provided new regulatory measures for integrated management of ground water and surface water. Natural resources districts (NRDs) have adopted allocations for ground water pumping in some areas. The North Platte NRD has established ground water allocations of 12 acre-inches in the Pumpkin Creek Basin and 18 acre-inches in the North Platte Valley for 2009. New or expanded ground water uses are prohibited throughout the NRD unless they are offset with transfers of existing uses.
Project goal: To develop the expertise in remote sensing image acquisition and computing, using the METRIC™ procedure; to produce area-specific consumptive water use (CWU) maps; and to develop, test and demonstrate the tools that will take these CWU maps and turn them into immediately usable products for planning, managing and regulating groundwater. The CWU maps will be the primary product of this project. They are developed from LANDSAT images by applying Mapping EvapoTranspiration with High Resolution and Internalized Calibration (METRIC™) algorithms.
The High Plains Aquifer