A decade ago, Pima County's Regional Wastewater Reclamation Dept., or RWRD, was facing a problem: The Arizona Dept. of Environmental Quality had ruled that the levels of nitrogen coming from RWRD's network of 10 wastewater-stripping and treatment plants were too high. As a result, RWRD embarked on a $720-million Regional Optimization Plan (ROMP) to improve the quality of its effluent.
The ROMP program is using innovative techniques as it expands and upgrades the 37.5-million-gallons-a-day Ina Road plant to 50 mgd and replaces an aging, outdated 41-mgd wastewater stripping plant with a new, state-of-the-art 32-mgd water reclamation plant at Roger Road. The plan also includes an interceptor sewer that reroutes flows from the Roger Road plant to the Ina Road facility, which was completed in December 2010.