Statewide Irrigation Systems Methods Survey
Beginning in 1991 and approximately every 5 - 10 years an irrigation questionnaire form is distributed by mail and online survey to California growers to update records on what types of irrigation systems are being used in California. The 1991, 2001, 2010, 2016, and 2021 surveys were distributed to growers who were randomly selected from a list of about 58,000 growers obtained from the [California Department of Food and Agriculture](https://www.cdfa.ca.gov/) (CDFA). All rice-only, non-irrigation, and livestock-only growers were excluded from the list. In these surveys, growers were also asked to identify the main county in which they farmed and the acreages they had planted to each of 20 possible crop categories along with the associated irrigation method within that county.
Data files
Supporting files
| Data title and description | Access data | File details | Last updated |
|---|---|---|---|
Statewide Irrigation Methods Survey The Statewide Irrigation Methods Survey is provided here as a Microsoft Excel application that allows users to easily access irrigation methods by crop category within each of California’s ten hydrologic regions, as well as statewide, for the years 1991, 2001, 2010, 2016, and 2021. The California Department of Water Resources (DWR) collaborated with the [California Department of Food and Agriculture](https://www.cdfa.ca.gov/) (CDFA) and the [National Agricultural Statistics Service](https://www.nass.usda.gov/) (NASS) of the [U.S. Department of Agriculture](https://www.usda.gov/) (USDA) to conduct statewide surveys to determine which irrigation methods growers use to irrigate their crops. For the 2021 survey, questionnaires were distributed by mail and through an online survey to 20,000 growers randomly selected from a list of approximately 58,000 growers provided by CDFA. Rice only, non-irrigation, and livestock only growers were excluded. The survey included 20 crop categories and 16 irrigation methods. The 2021 results reflect irrigation practices used during the 2020 growing season. | XLSM | 03/20/26 | |
Application Efficiencies in Irrigation Systems The Department of Water Resources (DWR) has developed the California Seasonal Application Efficiency Program to assess how efficiently irrigation water is being applied in California and to identify places where further improvements can be made. The program is presented here as a Microsoft Excel application that estimates seasonal application efficiency for 20 crop categories at the statewide, hydrologic region, and county levels from 2001 through 2021. Estimates of seasonal application efficiency are computed based on the Statewide Irrigation Methods Survey data, DWR statewide crop land use mapping, and theoretical application efficiency values for different irrigation systems. | XLSM | 03/20/26 |