Under the TWDB’s DWSRF Program, eHT conducted a full-scale pilot study for the first enhanced coagulation / ultrafiltration (UF) system in Texas for the City of Sweetwater. UF membranes were piloted with the following goals for the system: optimize organic removal performance; optimize membrane design parameters; turbidity/particulate removal capability; and the overall treatment capability of multiple surface water sources. The system evaluated three source water including a detailed pretreatment evaluation and foulant studies. eHT provided pilot testing, planning, design and construction services for the new 8.0 MGD plant. The design incorporated traditional rapid mix and enhanced coagulation / flocculation with state-of-the-art membrane technology for filtration. THM and HAA compliance is achieved using a combination of chlorine dioxide and chloramination. SCADA-integrated process controls allow treatment from four different water sources, including three surface water lakes and groundwater under the influence of surface water, producing potable water meeting primary and secondary drinking water standards. This project and pilot study were presented at the National AWWA Membrane Conference in 2003 and at Texas Water in 2004.

eHT is currently piloting a new membrane system to treat surface water and groundwater.