General Information

The ET Viewer uses ArcGIS Server .

ET Statistics are computed using ArcGIS Zonal Statistics as Table . If a water right or irrigation company is not completely covered by the ET data it will not be available in the list.


The initial page on the site shows the Landsat paths and rows from which the ET datasets were derived. You can select a dataset by clicking on the Find ET link and selecting a search-method. As stated above, only those datasets which entirely cover the selected entity will be shown. Regardless of search-method, you will see a list of all applicable ET datasets. Click the ET Statistics link for the appropriate dataset.

The Details page displays the selected ET dataset along with a background and any selected overlays, such as county boundaries, hydrography, etc. Note: If you experience a long wait-time when you initially load the Details page, select a different ET dataset from the drop-down list; wait until it loads, and then select the desired dataset.

You may change ET datasets at any time by choosing a new ET layer.

Change the background image or change other layers before you obtain statistics because the map is redrawn at that time.

Select a Method for Gathering Statistics

You may select an area for which to collect ET statistics by one of three methods. Select the type of statistics you want to obtain.

Irrigation Entities

Select the irrigation district, canal company, etc. from the list. The map will zoom to that area and the boundary will be drawn on the map.

Water Rights

Select the type of water right (right, permit, claim or recommendation). Enter the basin number, sequence number and suffix/version (if available). Click the Search link. Select the desired water use; in the case of the example, only a right for “irrigation” was found. The map will zoom to that area and the boundary will be drawn on the map.

Select Area by Polygon

Click the "Draw Polygon" button then draw the border of the area you wish by clicking on the map at each point on the polygon. Double-click to finish the polygon (to draw a rectangle, click three points and then double-click the fourth one). After you double-click to close the polygon the map will zoom to that area and the polygon will be redrawn on the map.

The Get ET Statistics link operates on the selected method (whichever method is indicated by the radio button). If you click the Get ET Statistics link when you have not selected an area for the chosen method you will receive an error message. For example, if you searched for a water right and the statistics method was 'irrigation entites' or 'select area by polygon', you might see the following:


Calculate the Statistics

Click the Get ET Statistics link. Warning! This operation may take a few minutes to calculate the statistics if you chose a large area. If you have correctly followed all of the steps, the statistics should show at the lower right corner of the page, along with links to methods to save the statistics:

Save the Statistics

You may save the statistics as CSV-formatted file or a PDF (which includes the map for the selected area). Here is an example of a PDF generated from a user-drawn polygon:


Contact the IDWR Geospatial Technology Section. Please include a detailed description of the problem you are having and the address of the web page you are using.