Carollo selected for Texas DPR health check

Carollo Engineers has been selected by the Texas Water Development Board to carry out detailed public health analysis of the first direct potable water reuse (DPR) facility in the USA.

Over the next year, Carollo staff will be performing detailed analysis and monitoring of the Big Spring advanced treatment facility, looking at advanced treatment performance, pathogens and trace pollutants.

The Colorado River Municipal Water District will reclaim the wastewater effluent from the City of Big Spring, producing approximately 1.8 MGD (6,800 m³/d) of raw water, which will be blended with other raw water from surface water reservoirs.

Although pilot testing of the membrane processes at the plant was conducted prior to the final design of the facility, it did not include the advanced oxidation process that typically follows membrane treatment. Additional testing at full scale with a broader list of parameters will better characterize the quality and consistency achievable with advanced treatment.

The goals of the study will be to determine the:

· Effectiveness and consistency of membrane filtration, reverse osmosis (RO) and advanced oxidation in removing or inactivating pathogens – such as Giardia, protozoa, Cryptosporidium, E coli and other organisms – from treated municipal wastewater in a full-scale facility under changing seasonal conditions and from various locations in the treatment process

· Accuracy, repeatability of results, evaluation of applicable primers and economic feasibility of using real-time, on-site analytical methods to test for Cryptosporidium and Giardia

· Accuracy and economic feasibility of using a surrogate (eg, conductivity) to conduct continuous integrity testing of RO membranes to remove Cryptosporidium and viruses

· Quality of “raw water” reclaimed from municipal wastewater effluent compared with other regional water supplies in terms of representative chemical compounds such as pharmaceuticals, personal care products, disinfection byproducts, industrial chemicals and other key chemicals of interest

· Changes in the quality of treated surface water when effluent-derived raw water is blended with other raw water sources; and water quality parameters that may require closer examination in the process of planning, designing and monitoring similar projects in the future.