The Brazos Regional Public Utility Agency (BRPUA) selected eHT to provide a detailed evaluation of the SWATS Water Treatment Plant (WTP). The SWATS WTP was rated to treat approximately 13.0 MGD through two parallel treatment trains. Each treatment trains utilized a different process methodology. The original treatment train (rated for 8 MGD when operated only, or 5.5 MGD when operated in parallel with the newer train) was based upon conventional treatment technology which utilized a rapid mix system for coagulation, upflow solids contact clarifiers for flocculation and sedimentation, and dual media filters for filtration. The newer treatment train (rated for 7.5 MGD) incorporated membrane technology. This train utilized a rapid mix system for coagulation, an upflow solids contact clarifier for flocculation and sedimentation, a pressure-fed ultrafiltration (UF) membrane filtration system, and a reverse osmosis (RO) membrane system. The SWATS WTP had multiple challenges over the years in consistently maintaining compliance with secondary standards, due to limitations in balancing flow between the two treatment trains. BRPUA selected eHT to evaluate each process within each treatment train and provide recommendations on system upgrades to enhance overall treatment consistency, as well as address current hydraulic bottlenecks, membrane oxidation issues, membrane fiber breakage issues, and operational flexibility for the existing UF and RO systems.

eHT took a multi-tiered approach for the evaluation of this facility. The initial step in the preparation of this Master Plan was to perform an extensive evaluation of the performance and condition of the existing treatment processes and equipment. This portion of the evaluation included the review of existing records and documentation, review of previous operational data, capacity analysis of each treatment system, review of historical demands, and review of current and anticipated demands on the system. Following the completion of the evaluation, Operational Round Table meetings were held to present the findings of the evaluation, receive feedback from all parties, and develop a prioritized list of processes in need of repair or modification. A Technical Memorandum (TM) was developed to summarize the findings the results of the Operational Round Table meetings. The prioritized list was used to conduct a Treatment Process Evaluation. This evaluation included the identification of any recommended treatment system modifications, upgrades and/or replacements as well as the evaluation of alternative treatment processes including impacts on the existing system, capital cost for the improvements or modifications, and anticipated operation and maintenance costs for the alternatives investigated. A final TM was developed to summarize the findings for each of the treatment processes and alternatives investigated. Those TMs were presented to the Owners, Operators, and Staff and were discussed at the Final Operational Round Table meeting.

Key challenges associated with this project included the following.

• Maximizing the use of conventional and advanced treatment processes in parallel;
• Coordination among multiple stakeholders and competing priorities; and,
• In-depth analysis of operational issues associated with the first Membrane and RO facility in Texas.