CIMIS, the California Irrigation
Management Information System, is a network of almost 100 computerized weather
stations, located at key agricultural and urban sites throughout California. Six
of these CIMIS stations are located in Santa Barbara County. The CIMIS program
was developed by the California Department of Water Resources (DWR) and the
University of California (UC) to help agricultural growers and landscape
managers irrigate more efficiently.
Improvements in agricultural and landscape irrigation efficiency can mean the difference between profit and loss to irrigation managers. Increased irrigation efficiency can reduce water, energy, labor, and fertilizer costs, as well as improve the health of the crop or landscape. Knowing when and how much to irrigate, however, can be difficult for irrigation managers to determine.
CIMIS can help by providing data to assist irrigation managers with their scheduling decisions.
Weather data is collected from each CIMIS station, fed into a centralized computer data base, and converted into reference evapotranspiration (Eto). Eto is the combined value of estimated daily pasture grass water use and soil evaporation.
Using crop coefficients and Eto, the water needs for a particular crop or turfgrass can be estimated. Crop coefficients have been developed for many vegetables, field crops, trees, vines, grasses, and landscape plants. Known crop coefficients are available in UC Cooperative Extension publications.
With this information, irrigators can establish an irrigation schedule. In many cases, proper scheduling can reduce the amount of water applied during a season, and at the same time improve growth.
There are three ways to access CIMIS Eto data for scheduling irrigations in Santa Barbara County.
1. You may access current Eto data by calling the toll-free CIMIS Hotline. The CIMIS Hotline for Santa Barbara County may be reached by dialing 1-888-CIMIS2U (1-888-246-4728). From the Santa Maria area, please call (805) 928-9344.
The Hotline is updated each weekday by 9:00 am with Eto data for the previous seven days for each CIMIS weather station in Santa Barbara County.
There are five mailboxes on the Hotline:
2. You may become a CIMIS user by acquiring a password to access the centralized CIMIS computer in Sacramento, using a computer modem. You can have a password assigned to you by calling 1-800-922-4647. Access to the CIMIS computer database is free of charge.
3. Through the internet, you can access Eto data for the last seven days, or monthly averages for the last eleven months. The internet address is:
For your information, contact any of the following offices:
Cachuma Resource Conservation District
University of California Cooperative Extension
California Department of Water Resources (DWR)
©1998 Montecito Water District