Biwater is Providing a Leading Edge Desalination Solution that Support’s San Antonio’s Long-term Water Supply Management Strategy
Biwater has been selected as the premier membrane solutions provider for a new brackish desalination program in Southern Bexar County, San Antonio, Texas. Since project award, the team have been finalising designs and preparing for system manufacture, delivery and commissioning.
Background: The South Central Regional Planning Group has identified brackish groundwater as a supply management strategy to meet the county’s water needs over the next 50 years. Brackish water is plentiful in the area and is a previously untapped local source of water. The Texas Water Development Board has confirmed that a vast supply of brackish groundwater – water too salty to drink – exists in the region and has yet to be developed.
To expand its water supply portfolio over the next 11 years the San Antonio Water System (SAWS) will deliver a phased program that will provide the county with over 30 million gallons per day (MGD (US)) of additional drinking water production capacity. The new brackish desalination plants will greatly reduce the population’s dependance on a primary drinking water aquifer, which will be able to recover naturally over time.
Phases: The Phase I facility will generate approximately 12 MGD from the Wilcox Aquifer and will be located at the existing SAWS Twin Oaks Aquifer Storage and Recovery Site. Thereafter, SAWS will complete Phases II and III, in 2021 and 2026 respectively, to bring the total capacity of the new facilities to over 30 MGD.
“This project award builds on our prior accomplishments in Texas. Our membrane technology expertise will be instrumental in ensuring that the first phase of this project delivers results ahead of SAWS embarking on latter project phases over the next 11 years,” said Jorg Menningmann, President, Biwater’s Desalination and Membrane Treatment Sector.
The Phase I facility will produce 12 MGD of finished water from 2 MGD of filtered well water blended with 10 MGD of reverse osmosis (RO) permeate water. The plant will accomplish 90 percent recovery by the inclusion of four 2.22 MGD primary RO trains and two 0.56 MGD secondary concentrator RO trains. Raw water will come from a combination of wells between 1,200 and 1,800 feet deep and the quality is expected between 1,300 and 1,500 parts per million (ppm) total dissolved solids (TDS). Brine disposal is via ‘Class 1’ injection wells. Finished water quality will meet all federal and local drinking water standards.
Entities involved in Phase I: For this initial phase, the Project Manager is Black and Veatch, the process Design Engineer is Tetra Tech, the Construction Manager at Risk (CMAR) is Zachry-Parsons and the Mechanical Contractor is Dynamic System Inc. Biwater was selected as the Reverse Osmosis System Supplier for the project and will be responsible for the RO trains, design of ancillary equipment as well as the RO system operation philosophy.