About Half of All Water Used in a Year is Outdoors.

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

Dollar sign with a sprinkler head graphic depicting saving water outdoors

Water Use Rules

Effective March 15,  Thornton City Council has declared a Stage 1 Drought. Wait to turn on sprinkler systems until May 1. The following turf/lawn irrigation rules will be enforced May 1 – October 31 (watering vegetable gardens and plant materials are not included):

Sprinkler head spraying grass

Outdoor Irrigation

  • Water no more than 2 days/week, between the hours of 6 p.m. and 10 a.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.
Closeup of broken sprinkler line spraying water

Water Leaks

  • A courtesy notice will be provided for water leaks.
  • Water leaks should be shut off or repaired as soon as possible, and not more than 10 days from the date of notice.
  • If water leaks are not remedied in provided time, residential penalty starts at $100 and commercial/irrigation penalty starts at $250.
Sprinkler head operating next to driveway

Water Waste

  • A courtesy notice will be provided for water waste.
  • Water waste should be remedied soon as possible, and not more than 10 days from the date of notice.
  • If water waste is 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 two days per week.

Total minutes per zone, per watering day. We recommend the Cycle & Soak method when possible, which means split watering times into three short cycles. Watering vegetable gardens or plant materials are not included. Download the Thornton Watering Guide for easy reference. 

2-Day Watering Guide | Minutes Per Zone, Per Watering Day:

The 2026 Thornton Watering Guide
Fixed spray nozzle. Rotor sprinkler type. Rotary nozzle. Manual sprinkler.
Fixed Spray Nozzles Rotors Rotary Nozzles Manual Sprinklers
Minutes Minutes Minutes Minutes
January-April Water trees and shrubs as needed
May 15 33 42 23
June 22 48 61 34
July 24 52 65 36
August 20 44 55 31
September 14 31 39 22
October Water trees and shrubs as needed

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 on the ground, you can water once or twice a month.

Finding and Fixing Leaks – Commercial Checklist

Leaks and inefficient water use can waste thousands of gallons and increase costs—often without being obvious. Use this Commercial Finding and Fixing Leaks Checklist regularly to identify, fix, and prevent water waste at your facility.

A screenshot of the first page of the commercial finding and fixing leaks check list

Watering your trees

Learn more about efficient tree watering throughout the year on the city of Thornton’s Tree Watering Guide.

How to efficiently water trees

H2Overhaul Your Yard

Check out H20verhaul, our step-by-step guide to transform your yard into a beautiful landscape—complete with detailed instructions, tips, and encouragements. Click the icons below to download the entire H2Overhaul kit and be well on your way to the higher ground of water-wiseness.

Water-Wise Demonstration 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. 

Five images of plants in gardens and people learning about them

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, with 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.

Screenshot of finding and fixing leaks document front page, with bar charts and text.

Finding and Fixing Leaks

Download the Checking for Water Leaks and Hidden Water
Waste Checklist for a step-by-step process to identify and
solve water leaks in your home.

Hidden Water Waste DeMistified thumbnail graphic

DeMistify Sprinkler System Leaks

Hidden leaks can lead to a lot of waste and a big increase in your water bill. Learn how to save by locating hidden drips so you can x ‘em quick on our Hidden Water Waste Fact Sheet. (Desmitificación de desperdicio de agua oculto). 

Irrigation Controllers DeMistified thumbnail graphic

DeMistify Your Irrigation Controller

Irrigation controllers are tricky. Learn about the basics on our Irrigation Controllers fact sheet and soak up the knowledge
you need to help master the programming process.
(Desmitificación de los sistemas de control de riego).

Cycle and Soak DeMistified thumbnail graphic

DeMistify The Cycle & Soak Watering Method

Use this water-wise method, Cycle and Soak Demistified, to save water and grow a strong, healthy lawn. (Desmitificaciòn de ciclo e infiltraciòn). 

Outdoor Tips

Know Your Responsibilities

If you’re dealing with a leak and are unsure whose responsibility it is to fix it, check out our water line repair responsibility graphics on our Saving Indoors page!

Spruce Up Your Sprinkler System

Learn how to fix any leaks or problems this summer season on the EPA’s Sprinkler Spruce Up web page or schedule a free sprinkler consultation with a trained technician on Resource Central website. 

Program Your Irrigation Controller

Learn more on our Youtube channel about how to schedule your residential irrigation controller yourself.