The Santa Cruz River once flowed year-round in Tucson, AZ, supporting one of the largest mesquite forests in the world. But urban development and extensive groundwater withdrawals in recent years caused the river’s volume to dwindle. Today, city administrators hope to use recycled effluent to restore the river’s flow to historic levels and revive riparian habitats.
The water—up to 3.5 million gallons a day—will come from Pima County’s Agua Nueva Water Reclamation Facility. Pending permits, the city plans to utilize existing pipes, currently conveying recycled water for irrigation, and build a small treatment facility near the river to extract chlorine from the water prior to its release.
In addition to replenishing the river, the water will also augment groundwater by feeding the aquifer. The City of Tucson may then receive a 50% “recharge credit” from the state for every gallon it releases to the river. In the future, it can then withdraw half of what it has released into the aquifer to use in its drinking water system.
“We don’t have to do this. We could be putting it into our recharge basin where we get 100% credit,” Maya Teyechea, a hydrologist with Tucson Water, told Water Deeply. “But the intent is to have nice areas where people can enjoy the river—hopefully a nice riparian area.”
As recycled water gains acceptance as a means of boosting water supplies, more communities are finding ways to benefit from reuse. What are your thoughts on using recycled effluent for restoration projects such as this?