Harvesting the Rain in Utah

By Clifton Smith, Conservation Garden Park

When the Mormon pioneers first arrived in Utah, they found an uninhabitable desert valley. Their first order of business was to divert and store water. Due to the scarcity of water supply, the use and ownership of water quickly became political; laws were created to establish water rights. These complicated laws take a lot of effort to describe, but simply put, precipitation belongs to the public but is managed by the State of Utah.

Before 2010, the state did not allow the collection and storage of rain water in order to protect water rights. In May 2010, limited collection and storage of rain water became permissible. Now homeowners are able to harvest up to 2,500 gallons of rain water per parcel. If the harvesting system consists of more than two containers or has a maximum storage volume greater than 100 gallons, it must be registered with Utah Division of Water Rights. Essentially, the rain that falls on your property, while not yours by law, can be captured and used to help water your landscape, hopefully reducing your overall landscape water need.

On some level, collecting rain water makes a lot of sense. Rain water harvesting is popular in many parts of the country but can be difficult in Utah because we receive so little precipitation. Here are some considerations for collecting rain in Utah.

You can only harvest rain when it’s raining (or snow is melting) so storage is key. The legal maximum storage capacity of 2,500 gallons seems like a lot of water but, in Utah, it can take a long time to collect that amount. By contrast, the average amount of water used for a typical quarter acre lot per irrigation cycle is 2,000 gallons. Multiply that by 3x per week and in a single summer week, a home could use upwards of 6,000 gallons on their landscape. While harvested water can help supplement your watering, substantially greater savings may be achieved through watering the yard more efficiently.

Finally, rain harvesting systems can get expensive–really expensive–especially if you add anything like gauges, pumps or fancy filters. If you cut out the unnecessary bells and whistles, simple homemade rain harvesting systems can be cost effective.

These considerations create a pretty bleak outlook for rain harvesting. However, don’t despair. So long as you understand the limited benefit, rainwater harvesting can be a nice way to supplement irrigation for your waterwise landscape.

At Conservation Garden Park, we’re experimenting with rain harvesting systems to better determine the advantage of a system and how to use it wisely. To help us, we’ve constructed a 200-gallon rain harvesting system with help from the Utah Division of Water Quality. We’ll use it to test how much area of waterwise plantings we can water with the harvested rain.

You can come see it for yourself. Conservation Garden Park is free to visit at 8215 S. 1300 W., West Jordan UT. Check www.ConservationGardenPark.org for open hours.