The Irrigation Water Management Society

Use these water budget calculators to estimate how much supplemental water a lawn needs to stay green and healthy, based on the size of your irrigated landscape and yearly weather averages for the Seattle area. The Intermediate calculator helps you compare your actual water use with your landscape's estimated watering requirements.

Please choose from the options below

Annual estimated water budget - for manually adjusted controllers

Custom budget based on water bills

NOTE:
these calculators only work in the Seattle area

The use of the weather network constitutes your acceptance to these terms of use.