What is rain water harvesting?

Rain water harvesting is a technique of capturing rain for human use that has been around for thousands of years.  We commonly refer to them as rain barrels and they are an example of green infrastructure.

Why would I want to capture rain water?

A half of inch of rain on a 1000 sq. foot roof produces approximately 280 gallons of water!  Even in a dry state like Utah, up to 5000 gallons of storm water runoff could be captured from an average roof.

This water is not safe for human consumption, but can be used to water your garden and landscaping or used to clean items around your home.  This helps conserve water and could lower your water bills.

Rain water harvesting also helps the environment by preventing storm water runoff from carrying trash, nutrients, and other pollution to our local lakes and streams.

Is rain water harvesting legal in Utah?

Yes!  On May 11, 2010 Senate Bill 32 went into effect which allowed for legal harvesting of rain water in Utah.  This law was amended in 2013 with House Bill 36 and approved for the current regulations as of May 14, 2013:

  • Total volume of rain water harvesting containers cannot exceed 2,500 gallons per parcel
  • Containers may be above or below ground as long as they meet building codes

Parcel owners need to register their rain water harvesting system if:

  • They have more than two covered containers
  • Any container has a maximum storage volume greater than 100 gallons

If your system meets either of these conditions then you need to register your system online.  This is a free registration that requires your name, address, and the total volume of containers.

How to install a rain water harvesting system?

There are many different options depending on your roof, how much water you want to capture, and how much you want to spend on the project.  Consult with a local landscaper, home improvement store, or search the internet.  There are many options that can create a system that is perfect for your needs.

Rain barrels do need periodic maintenance to clean them out, prevent mosquitoes, and to store them in the winter to prevent them from freezing. We recommend systems with diverters from the downspouts which make for easy maintenance.

Basic Top Inlet Design

Rain Barrel with Diverter Design


Utah Water Watch's Citizen Science Rain Barrel Project for Schools

Utah Water Watch has started a citizen science project to monitor how much storm water runoff can be captured by 55 gallon rain barrels.  Visit the website for more information or contact USU Water Quality Extension if you would like to participate.