By J.R. Masoner, C.S. Mladinich, A.M. Konduris, and S. Jerrod Smith
Water-Resources Investigations Report 03-4155
Prepared in cooperation with the
Oklahoma Scenic Rivers Commission Oklahoma Water Resources Board
The report is available in PDF format.
Increased demand for water in the Lake Altus drainage basin requires more accurate estimates of water use for irrigation. The U.S. Geological Survey, in cooperation with the U.S. Bureau of Reclamation, is investigating new techniques to improve water-use estimates for irrigation purposes in the Lake Altus drainage basin. Empirical estimates of reference evapotranspiration, crop evapotranspiration, and crop irrigation water requirements for nine major crops were calculated from September 1999 to October 2000 using a solar radiation-based evapotranspiration model. Estimates of irrigation water use were calculated using remotely sensed irrigated crop acres derived from Landsat 7 Enhanced Thematic Mapper Plus imagery and were compared with irrigation water-use estimates calculated from irrigated crop acres reported by the Oklahoma Water Resources Board and the Texas Water Development Board for the 2000 growing season. The techniques presented will help manage water resources in the Lake Altus drainage basin and may be transferable to other areas with similar water management needs.
Irrigation water use calculated from the remotely sensed irrigated acres was estimated at 154,920 acre-feet; whereas, irrigation water use calculated from state reported irrigated crop acres was 196,026 acre-feet, a 23 percent difference. The greatest difference in irrigation water use was in Carson County, Texas. Irrigation water use for Carson County, Texas, calculated from the remotely sensed irrigated acres was 58,555 acrefeet; whereas, irrigation water use calculated from state reported irrigated acres was 138,180 acre-feet, an 81 percent difference. The second greatest difference in irrigation water use occurred in Beckham County, Oklahoma. Differences between the two irrigation water use estimates are due to the differences of irrigated crop acres derived from the mapping process and those reported by the Oklahoma Water Resources Board and Texas Water Development Board.
Download the PDF version of the report for high-resolution, printable pages (5.5MB).
Sections available in pdf:
Purpose and Scope
Description of study area
Historical freshwater withdrawals
Determination of land use and irrigated crop acres by remote sensing
Suggestions to increase accuracy
Limitations of landsat
Remotely sensed irrigated crop acres
Irrigated crop acres from state water boards
Irrigation water requirements
Determination of irrigation water requirements
Irrigation water use calculated from remotely sensed irrigated crop acres
Irrigation water use calculated from state reported irrigated acres
Comparison of irrigation water use calculated from remotely sensed irrigated acres with irrigation water use calculated from state reported irrigated acres
For additional information write to:
U.S. Geological Survey
202 NW 66 St., Bldg. 7
Oklahoma City, OK 73116
Copies of this report can be purchased from:
U.S. Geological Survey
Denver, CO 80225
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