IDWR Evapotranspiration Viewer

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There are two ways to use the ET Viewer to calculate ET statistics:

Go to the page where you can find ET datasets by date, county, administrative basin, irrigation company or Landsat path/row. This takes the same action as clicking the Find ET link, on the toolbar.

Use this map to zoom to your area-of-interest and then click the map. That action causes the ET statisics page to be displayed; the map will be positioned to your area-of-interest. The most recent seasonal ET dataset for the area will be displayed.

Use the Help link, on the toolbar, to see how to run the tools.

About the ET Data

The evapotranspiration (ET) data were developed using the METRIC model and Landsat satellite data. METRIC is a satellite-based surface energy balance model developed by the University of Idaho .
Most of the ET data are referenced by Landsat Path and Row. Idaho is covered by paths 38 to 43 from east to west and by rows 26 to 31 from north to south, as shown on the interactive map. Each Landsat image is approximately 180 km in length and 185 km in width.

About the ET Viewer

The IDWR ET Viewer allows users to find evapotranspiration (ET) datasets for Idaho, display them on a map and calculate ET and consumptive irrigation requirements (CIR) statistics for an area. It has built-in tools to help you select an irrigation company or water rights place of use as your area-of-interest. Alternatively, you can draw a polygon to define your own area-of-interest or select from irrigated lands polygons.