Finding new sources of water for semi-arid cities in unlikely places

Determining alternative water sources to meet municipal water demands is important when availability is limited. The purpose of this study was to demonstrate a means for water planners to estimate the amount of combined sanitary wastewater and storm water that they might already be capturing through open air oxidation ponds. Increased understanding of the quantity of water that is already available could help water planners to better envision optimal water reuse scenarios. Using water and climate data on oxidation ponds in these three cities within the Texas Panhandle from 2010 to 2014, we evaluated water quantities which would be available for potential reuse. From the net monthly wastewater volumes values, the study also considered if per capita demand could have been met by reusing the wastewater. The study found wastewater volumes were lower in fall and winter months and much higher in spring and summer months. If a city considers reusing wastewater, blue water (groundwater) extraction could be reduced by as low as 45-50% in one city to as high as 100% in another. Water planners in similar environments and wastewater treatment systems may find this demonstration of potential reuse water quantity encouraging for better meeting their own water demands and enhancing water supply resiliency.