Process_Description:
2005 other irrigated areas (non-center pivot) data layer was created using irrigation information provided from the Nebraska Department of Natural Resources (NDNR), Public Power Districts, and Nebraska Natural Resource Districts.
The 1997 and 2001 other irrigation layer previously developed by CALMIT was updated using 2005 field data obtained from Nebraska Natural Resources Districts. Previous data layers obtained from NDNR included irrigated acres from Pathfinder Irrigation District. Pathfinder Irrigation District keeps DXF files of all of their irrigated acres. The original section sized Pathfinder Irrigation District DXF files were brought into ArcInfo, edited, attributed, and appended to create one larger area map for use in the Platte River Cooperative Hydrology Study. Irrigation maps were also obtained from the Nebraska Department of Natural Resources. These paper maps identifying surface water irrigation rights were digitized using ArcInfo. The canal project maps include; Castle Rock, Steamboat, Chimney Rock, Empire, Midland-Overland, Graf Canal, Keith-Lincoln, North Platte Canal (Platte Valley I.D.), Paxton-Hershey, Birdwood, Suburban, Cody-Dillon, Western Canal, Thirty Mile Canal, Six Mile Canal, Cozad Canal, and Orchard-Alfalfa Canal. These maps were individually digitized and then merged into one map. Irrigation data was also obtained from the Central Nebraska Public Power and Irrigation District. The Central Nebraska Public Power and Irrigation District keeps all of their irrigated acres as DXF files. The original section-sized DXF files were imported into ArcInfo, edited, attributed, and appended to create one larger area map. Irrigated areas identified on the Nebraska and Wyoming border were provided by the Wyoming Water Resources Center. Irrigated areas identified on the Colorado and Nebraska border were interpreted using irrigation well data provided by the Colorado Division of Water Resources.
Irrigated areas were checked for accuracy using registered irrigation well data, 2005 multi-date Landsat 5 satellite imagery, and 2005 Farm Service Agency (FSA) Ortho Imagery. The overall accuracy for the irrigation layer was calculated at 93.30%. This project was part of a joint research project with the Nebraska Department of Natural Resources.