Welcome to when2water. Just follow our 3 easy steps and you’ll be on your way to saving up to 80% on your outdoor irrigation water bills using our Google Science Fair award-winning algorithm:

1. Enter your zip code as well as any odd/even watering restrictions you have on the left. Then click “Go”

2. View your custom watering recommendation! If the system tells you to water today, then turn on your sprinkler system. Otherwise, turn it off to save water and money.

3. Come back tomorrow and repeat to view your new recommendations.

And that's it! Learn more about us on the About Us page, or if you're interested in the nitty-gritty of our algorithm, check out the How It Works page. Remember, our service is free and always will be. We hope you find it as useful as we do, and most of all, we hope you enjoy saving water and money as much we do! Thanks!