The Town of Marana will soon be turning sewage into a community park thanks to their recently opened Water Reclamation Facility. The “100 percent recharge” facility will pump purified wastewater back into the ground, refilling the aquifer and nourishing a nature park.
“Two score and one year ago, our forefathers and foremothers set out to incorporate this plot of God’s green earth,” Marana Mayor Ed Honea said at the facility’s grand opening. “And it was all about water.”
The new facility, located in the northwestern cotton fields of Marana at 14393 N. Luckett Road, was originally a far smaller operation owned by Pima County. Marana now manages the facility itself, and receives water credits for refilling the town’s aquifer.
According to Marana Water Director John Kmiec, the town’s primary objective is to make sure it maintains and builds upon its clean water portfolio.
“Reclaiming water is ultimately what we needed to do, especially for being a town in Arizona,” Kmiec said.
The new facility went online June 19, though the nearby nature park is a few years off. While the site is currently a dirt basin with a drainage valve in the middle, over time, as it receives all of the outflow from the Water Reclamation Facility, Kmiec said the basin will grow into a lush destination for both birds and residents. Future infrastructure developments for the park are expected to be decided in Marana’s 2020 budget.
The town purchased the facility and land from Pima County in 2012. At that point, the facility treated 500,000 gallons of wastewater per day. Foreseeing a need for a larger facility to service the ever-growing Marana, the Town Council voted to fund an expansion of the Water Reclamation Facility in 2016. The Water Reclamation Facility can now treat 1.5 million gallons of wastewater per day through a series of water purification steps called the “Bardenpho Process.”
First, the facility removes all solid material from Marana’s wastewater via a series of grinders and screens. The water then goes through biological treatment, where both aerobic and anaerobic bacteria remove the nitrogen and sulfur from the water.
“This is where a majority of the treatment takes place,” Kmiec said.
The denitrified water then flows through “clarifiers,” where particles are filtered out and sludge is condensed to the bottom. In a high-tech addition, instead of having to add chlorine to the water, ultraviolet lights sanitize away any additional bacteria.
Finally, the sludge from the clarifiers, which is made up of 99 percent water, is squeezed dry.
“This is the moneymaker for the facility, right here,” Kmiec said. “This was probably our biggest advancement.”
Whereas shipping the large amounts of sludge to Casa Grande once cost Marana roughly $400,000 a year, by stripping the sludge of its water, costs are down to $50,000. With these savings, the town estimates the facility will pay for itself in only a few years.
Marana estimates the facility’s capacity will suffice through the next decade, but will eventually needs to expand. There is enough room on the current facility land to install two more reclamation facilities, ultimately being able to process roughly 4.5 million gallons of wastewater per day. With the nature park/aquifer recharge able to handle about 2 million gallons of water, this would necessitate building an additional, adjacent aquifer recharge facility.
“We’re going to have plenty of capacity for the town of Marana to grow out,” Kmiec said. “The whole Marana water system will benefit from this facility.”
The Town of Marana says this new facility will naturally recharge around 500 acre-feet of groundwater per year. Whereas it used to cost the town about $700 per acre-foot to put water back in the ground, this method will save the town some $350,000 a year.
“We’ve come a long way.” Honea said. “I’m very proud of our community and our staff for what we’ve done… Not only is this a great wastewater plant, but it’s also going to be a great public amenity as a park.”