More than 560 million gallons of water fall on Moab each year, according to the U.S. Geological Survey. Moab organizations, including Utah State University and the City of Moab, are starting to imagine what the community could do if it harvested some of that water.
One inch of rain equals approximately 27,154 gallons of water per acre. Moabgets an average of about nine inches of rain a year, over its approximately 2,304 acres.
After attending a USU urban-water-harvesting workshop at the local campus, City Council member Heila Ershadi and Moab community-development director David Olsen invited USU professor Roslynn Brain, and Jeremy Lynch, the USU Extension sustainability intern, to present on the issue at the Moab City Council meeting, which took place on Tuesday, March 4.
Water harvesting—capturing, diverting and collecting rain run-off for plant irrigation and other uses—is an ancient idea that was illegal in Utah until 2010. The practice was controversial because of the belief that harvesting water was essentially stealing it from downstream water-rights owners.
Modern research allayed many of those concerns. A 2007 study for the Colorado Water Conservation Board and Douglas County, Colo. determined that, on average, only 3 percent of precipitation returns to a stream. That same study also determined that water-harvesting techniques, used with drought-tolerant landscaping, could reduce outdoor water demand by up to 88 percent.
Those are attractive statistics in the arid West, where more and more states and municipalities are taking the practice seriously. Utah Senate Bill (SB) 32 made water harvesting legal in Utah—and it’s an idea that seems to be gaining momentum in Moab.
“We had talked so much about rainwater harvesting, it was time to invite somebody to speak to that particular topic,” said Emily Niehaus, executive director of Community Rebuilds. Part of Community Rebuilds’ mission is to build affordable housing for the community and provide education and skills in natural building.
In spring 2013, Community Rebuilds invited Brad Lancaster, of Tucson, Ariz., to lead a local workshop.
“When anyone talks about who they learned rainwater harvesting from, it’s pretty much Brad, or someone who learned from Brad,” Niehaus said.
Niehaus’ goal was to plant the idea of water harvesting in Moab. It has spread from that workshop to other organizations, including USU and the Moab City Council.
“We need to shift our focus from moving water away from a property to understanding how we can hold it and use it when it falls,” Ershadi said.
Lynch said a large project is taking place to manage water on the USU-Moab campus.
A previous system installed on the east building included a gravel-filled trench, or French drain, and an underground tank.
“But essentially what it was doing was capturing the rain water from the building and flushing it off the property,” Lynch said.
As part of a larger permaculture initiative, USU wanted to redesign the system to make use of the water.
“We’ve redesigned the project with the help of Jason Gerhardt from Naropa University and we’re going to establish rain-gardens on the north and south sides of the building to infiltrate the water into the ground and establish teaching and educational workshops and garden spaces,” Lynch said.
The USU project will be just one example of the many ways urban buildings and city infrastructure can integrate water-harvesting techniques to direct rainwater into landscaping. During their presentation, Brain and Lynch demonstrated the water-wise uses of landscape basins and swales, water-channeling curb systems, and permeable hardscapes in municipalities.
“The idea is to look at the infrastructure we’ve already put in and just make little adjustments here and there whether it’s cutting curbs so you can flush water into an earthen area or catching water in a cistern and slowly trickling it into a garden space,” Lynch said.
The city has already used similar concepts in the landscaping in the front of City Hall and its back parking lot where rain water drains into the planters. Rainwater, being free of chlorine, is more beneficial to the plants than treated city water, and channeling or storing rain run-off can also diminish flooding and erosion issues, city manager Donna Metzler said.
“With water being at the forefront of a lot people’s minds lately and some people voicing concerns about it, we’re looking closely at where water is used the most and how we can address and conserve water use among the higher users,” Ershadi said.
In a February presentation of the city’s current water resources and use, Metzler said the biggest water users are the city-owned entities. The Moab Golf Club uses 40 million gallons per year, and the wastewater-treatment plant uses an additional 13 million gallons per year. In 2013, the average household in Moab used 185,000 gallons of water.
Outdoor water-use is likely the greatest drain, as about 60 percent of the water supply is provided during the summer months, City Engineer Rebecca Andrus said. All of that water currently comes from Moab’s drinking-water supply, the Glen Canyon aquifer.
Even though Moab is using only 40 percent of the water for which it holds rights, Metzler said, future projections show a need for planning. A 2011 needs assessment by the Utah Division of Water Resources estimates that “as Grand County population increases, communities will be limited by the volume of water they can deliver with their existing systems by 2020. By the year 2050, some communities will have insufficient water supplies.”
Rainwater harvesting can reduce dependency on groundwater, and with the new laws, people can collect and store rainwater without obtaining a water right. Anybody can store rainwater in two above-ground storage containers smaller than 100 gallons as long as that water is used on the same parcel of land from which it was collected.
If a person registers with the Utah Division of Water Rights, he or she can legally collect and store up to 2,500 gallons of rain water in an underground container, or 200 gallons in two separate above-ground containers. Registration is free.
Rainwater can easily be collected from a house roof using gutters and downspouts. A 1/2- inch of rain on a 1,000-square-foot roof can shed about 280 gallons of water, according to the USU Extension Web site.
A challenge for now is collecting runoff from the streets, Niehaus said.
“Whenever it rains I see a river flowing down the street and if I were able to cut my curb and have a diversion for some of that water to come in and saturate a planted area, then that’s another way of practicing rainwater harvesting,” she said.
The City of Moab, however, is just beginning to consider the possibilities surrounding water harvesting.
“We haven’t talked about it enough, which is why we had that presentation to see what interest there is in all of this,” Olsen said. “This is kind of where we get started.”
Residents see practice as step toward sustainability
“We need to shift our focus from moving water away from a property to understanding how we can hold it and use it when it falls.”
Find more information about water harvesting techniques through the USU Extension at extension.usu.edu.
Find more information about Utah water harvesting codes, or register to harvest rain water at waterrights.utah.gov