ET hotline
Call the ET hotline for potable and recycled water weekly budgets.
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Weather center
IRWD operates three weather stations to continuously monitor conditions that directly affect your water needs.
How weather stations work
Our service area has three distinct microclimates, known as the Coastal, Central and Foothill zones. IRWD maintains a separate weather station in each climate zone to monitor exact wind and weather conditions. Data is electronically transmitted daily to IRWD, where it is used in a formula to calculate evapotranspiration (ET), which is the amount of water needed by grass to remain healthy in each specific climate zone.
Outdoor watering accounts for 40%-70% of water used in Orange County. With thousands of acres of valuable community parks, gardens, and greenbelts within its boundaries, IRWD’s billing system relies on accurate weather station data to provide landscape, commercial, and residential customers with site-specific budgets to ensure that your landscaping receives sufficient water.
Weather reports
Weekly ET data is updated every Monday by 10:30 a.m.
Weather station technology saves water
IRWD uses the most advanced weather station technology, consisting of Campbell Scientific CR-10X Data Logger equipment — the same used by the California Department of Water Resources for California Irrigation Management Information System stations around the state.
How weather determines your water budget
When the weather is hot or windy, your budget goes up automatically. When it’s cool or rainy, your budget decreases. It’s important to adjust your irrigation based on the season.
The goal is to allow you the correct water budget you need for your landscape to stay healthy and attractive. Using more water than plants need is a waste of water and money, leads to unhealthy plants, and can contribute to pollution-causing urban runoff.
