Watering calculators for California
Free, anonymous, and every result prints the formula that produced it. Both calculators read the same verified state datasets as the rest of the site.
- You need
- Your city, what the zone grows, the sprinkler type
- You get
- Minutes per watering day, split across the days your supplier sets
- You need
- Your city and each zone's area, plants and irrigation type
- You get
- The project's yearly use against the state cap, zone by zone, with the math shown
Start from your water days
The run time calculator does not know which days your supplier allows unless you start from a schedule page. The 54 supplier pages on this site each open it with the right days already set.
The personal watering plan does every zone for every month
A PDF in one of fourteen sheet designs, with your supplier's days and hours and the minutes for each of your zones in all twelve months. $19 once, 30-day money-back.
Build your planThe state water efficient landscape worksheet, filled in
Appendix A of the state ordinance as a PDF, filled from your zones, areas and city, with every number worked out on the pages after it. $39 once, one free regeneration, 30-day money-back.
Fill in the worksheetThe data behind both
Both calculators read the climate number for your city from the adopted state reference table, which covers 676 California cities, and the plant water rating from WUCOLS IV, the University of California plant database that cities use for plan review. The run time calculator adds published nozzle precipitation rates; the water budget calculator adds the irrigation efficiencies fixed by the state ordinance. Each page lists its sources with the date they were read.