Alert 1/7/21 | 10:59 AM: Regional Stay Home order continues. Your water remains safe throughout Santa Clara County. LEARN MORE HERE
Water Conservation
Help make conservation a California way of life
saving water header
Page Title
Saving Water
Back to top



In Santa Clara County, as in the rest of California, water availability and pumping costs are important considerations for the agricultural industry. Efficient irrigation methods and scheduling are the key to maximizing water and fertilizer use efficiency, with which the resources below may help.

Estimating crop water requirements: 

The graphs obtainable by clicking on the [PDF] links below show the estimated cumulative irrigation requirements for several crops of importance in the Llagas Valley. Crop specific details are included below each graph.

Alfalfa Celery
Cherry Corn
Dry Beans Peppers
Walnuts Wine Grapes
Stone Fruit Tomatoes

Agricultural customers can increase water-use efficiency with the following resources:

Handbook for Agricultural Water-Use Efficiency

This handbook describes how to integrate into your operations the tools that are available to you as a Santa Clara County grower:

  1. Irrigation system fitness and distribution uniformity (DU), payback from improving DU, and evaluating pump efficiency.

  2. Irrigation scheduling and evapotranspiration, maximizing the amount of marketable crop produced per unit water consumed, using the online irrigation calculator, and evaluating Available Water Capacity.

  3. Soil moisture monitoring, including calculating soil moisture and describing guidelines for placing sensors.

  4. Setting irrigation run times for sprinkler and drip irrigation.


On-line Irrigation Scheduling Calculators

Valley Water provides two calculators to estimate the irrigation water used by your crop the last few days (“in arrears”), and to forecast your crop’s water use in the coming few days (“in advance”). 

These calculators make it easy to calculate your crop's irrigation requirements based on your local CIMIS weather station data and the percentage of your field that is shaded by the crop around high noon. Of course, it's essential to check your soil moisture to ensure that your calculated irrigation amounts are doing the job.

The calculators ask for some information that you may not know yet. The calculators will suggest values you can plug in to get at least a provisional answer. Then, call Valley Water at (408) 630-2951 to schedule an irrigation system evaluation during one of your normally scheduled irrigations, and we will develop the rest of the information so you can use the calculator for more precise estimates.

California Irrigation Management Information System (CIMIS)

To help maintain the most efficient irrigation scheduling, the California Irrigation Management Information System provides current reference evapotranspiration. Valley Water maintains a CIMIS station in Gilroy updated daily, in partnership with Synsenta AG and the California Department of Water Resources.

This CIMIS brochure will describe how CIMIS works, how you can access it, and how you can use it as a tool for irrigation scheduling at your farm, orchard, or nursery.

Mobile Lab: System Efficiency Test Program 

Find out how uniformly your system is irrigating your crops with the water district's mobile lab service. An experienced technician will analyze your system's performance and suggest improvements where appropriate.

New!!  PG&E's Agriculture and Food Wastewater Energy Program (WEP) 

WEP helps agriculture-, food-, and beverage-processing facilities implement energy efficiency and water conservation projects. Learn more here!

QUESTIONS? Call (408) 630-2951. For general information, contact the Water Conservation Hotline at (408) 630-2554 or email us at [email protected]