About half the water used in a year is outdoors.

Reducing outdoor water use is the biggest way to save, has the largest impact on your water bill and it’s easy to do. You don’t even have to give up your green lawn! There are efficient and effective watering practices, low-water plants and grasses, hardscaping features, and other water-wise options that let you stay green while caring for the blue.

Water Use Rules

In 2021, Thornton City Council adopted permanent Water Use Rules into City Code. The following turf/lawn irrigation rules will be enforced April 1 – October 31 (watering vegetable gardens and plant materials are not included):

  • Water no more than 3 days/week.
  • No lawn irrigation between 10 a.m. and 6 p.m.
  • Vegetable gardens and other gardens may be watered as needed.
  • Exceptions will be made for new sod, seeding and reseeding of lawns.
  • Exceptions will be made for large properties that cannot irrigate appropriately within the restricted schedule.
  • Water waste must be remedied as soon as practicable, no more than 10 days after notice.
  • Water leaks must be remedied 10 days to repair after notice.
  • A courtesy notice will be provided for leaks and water waste. If not remedied in provided time, residential penalty starts at $100 and commercial/irrigation penalty starts at $250.

Consult our Watering Guide below every month for recommended number of minutes for watering lawns.

Thornton Watering Guide

For watering your lawn up to three days per week.

Total minutes per zone, per watering day. We recommend Cycle & Soak when possible. (Break watering times into three short cycles.)  Watering vegetable gardens or plant materials are not included. 

Fixed Spray Nozzles Rotors Rotary Nozzles Manual Sprinklers
May 12 mins 24 mins 30 mins 18 mins
June 17 mins 35 mins 43 mins 26 mins
July  18 mins 36 mins 45 mins 27 mins
Aug 14 mins 27 mins 34 mins 20 mins
Sept 11 mins 23 mins 28 mins 17 mins

October-April: Winter Watering
During colder months snow does a good job of keeping trees, shrubs, perennials and lawns hydrated so you don’t have to. If it’s over 40 degrees and there’s no snow you can water once or twice a month.

Watering your trees.

Learn more about efficient tree watering throughout the year.

H20verhaul Your Yard

Check out our step-by-step guide to transforming your yard into a beautiful landscape, complete with detailed instructions, tips and encouragements. Click the icons below to download the whole H2Overhaul kit and you’ll soon be well on your way to the higher ground of water-wiseness.

Demo Gardens
You can have a spectacular yard, increase your curb appeal and property value, and yes, save gallons of water and boatloads of dollars, too. Here are some examples of gardens we love for all the reasons above. Feel free to visit these gardens and get inspired. 

Visit our demonstration gardens:

Thornton Fire Station 5, 14051 Colorado Blvd.


Carpenter Recreation Center, 11151 Colorado Blvd.


DeMistify Facts — Outdoors
Welcome to our DeMistify series. Everything you wanted to know about where your water goes. Learn how to cut down your utility bill and conserve water outdoors by locating sneaky leaks and irrigating and watering more efficiently. Find tips on how to save indoors here.

Outdoor Tips

Read The Outdoor Water-Saving Checklist 

Our top 10 tips to help you take control of your use and get more out of your water.

Spruce Up Your Sprinkler System 

Fix any leaks or problems before the summer season (learn how here) or schedule a free sprinkler consultation with a trained technician.

Program Your Irrigation Controller 


Schedule your residential irrigation controller yourself.