ET Hotline |
English |
949-453-5451 |
Coastal, Central and Foothill weather station data is electronically transmitted daily to IRWD where it is used in a formula to calculate evapo-transpiration, also known as ET, which is the amount of water needed by turfgrass to remain healthy in each specific climate zone. Outdoor watering accounts for 40 to 70 percent 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 and commercial customers like you with site-specific budgets to ensure that your landscaping receives sufficient water. |
Important Links |
Experiencing technical issues with links below? Please call ET hotline (949-453-5451 for English and 949-453-5452 for Spanish) for potable and recycled water weekly budgets. MAP: Evapotranspiration Zones + Weather Station Locations *Weekly ET data should be up to date by Monday at 10:30 a.m. PT. |
Historical ET Data |
Most recent |
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2010-2019 |
2019 | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 | 2012 | 2011 | 2010 |
2000-2009 |
2009 | 2008 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
1997-1999 |
Weather Determines Your Water Budget |
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How Weather Affects Your Water Budget: When the weather is hot or windy, your budget goes up automatically. When it's cool or rainy, your budget decreases. Staying Within Budget Makes Sense: 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, a waste of your money, leads to unhealthy plants, and can contribute to pollution-causing urban runoff. |
Weather Station Technology Helps You Save Water |
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