Challenges are not unique to water and wastewater treatment, but the challenges thrown at operators and managers often require equal parts of thoughtfulness and creativity, with dashes of patience and persistence.
This is why the industries are “home to some of the most ingenious professionals to be found in any industry,” according to an editorial in Treatment Plant Operator.
When flies became attracted to the 25-acre biosolids drying beds at the Dos Rios Water Recycling Center in San Antonio, Texas, the pests were promptly addressed by Ted Eaton, manager of the facility’s biosolids program. He first installed purple martin nesting boxes in the 1990s and today they number about 50.
The birds find the insects tasty.
When the birds vacate (they’re active between February and July), three species of tiny parasitic wasps are used to combat the flies. And soil bacteria are used to eliminate pesky fungus gnats.
Eaton has spent 20 years perfecting natural alternatives to pest control at the facility, according to the San Antonio Express-News. The United States Environmental Protection Agency and the Texas Commission on Environmental Quality have honored San Antonio Water Services for its operations at Dos Rios.
In addition to reducing the use of chemicals for pest control, it also recycles water, which is used for irrigation, and recovers biogas from the sludge production process. Some of the remaining sludge is composted.
Tasteful Alternative to Chlorine
When a new state requirement meant adding a disinfecting step to its drinking water treatment, Montana’s Big Sky County Water & Sewer District had several options. Rather than using chemicals that might compromise the taste of the local water, officials opted for ultraviolet disinfection. The utility, after all, had won the 2015 Best of the Best Tap Water Taste Test from the American Water Works Association.
Ron Edwards, water and wastewater system manager, told Treatment Plant Operator :
We bent over backward and spent more just to keep from having to add chlorine.
Saving on Maintenance
In Crown Point, Indiana, what started as a filter upgrade at the local wastewater treatment plant resulted in a complete change in technology. Moving from pressure filters to gravity-flow disc filters eliminated the need to maintain equipment, saving $70,000 a year in operations and maintenance costs.
The installation of the $2.5 million system also qualified the plant for an energy efficiency rebate of almost $30,000 from the Northern Indiana Public Service Co.
Protecting Freshwater Sources
The need to conserve and protect freshwater sources resulted in a unique collaboration between packaging products manufacturer Sealed Air, Iowa Park’s Economic Development Corp. and Community Development Corp., and the Wichita Falls Economic Development Corp. The group wanted to push water reuse through a project to conserve 18 to 20 million gallons of drinking water each year by recycling municipal wastewater for use in Sealed Air’s cooling tower.
The facility assessed its annual water use and found cooling was consuming about 20 million gallons, roughly a third of its yearly potable water demand. The project cut the facility’s potable water use by 40 percent.
Barry Hardin, North American operations director for food care at Sealed Air, was the plant manager at Sealed Air’s Iowa Park facility when the project started in 2015. He told Triple Pundit:
Always work on internal efforts to reduce total water consumption, and actively partner with local leaders to initiate creative ways to conserve potable water for the community through innovative collaboration. […] It is very important to ensure that all parties clearly understand the goal and the long-term economic and social benefits of these types of projects. […] City leaders from Iowa Park, Wichita Falls, and leaders from SAC were in full agreement that a cooperative effort was in the best interest of the residents of the community and local industry.
These are just a few examples of the creative, successful solutions applied to water and wastewater treatment challenges. For more ideas, tips, and solutions, please check the Fluence blog and website regularly.