Turning Brackish Groundwater into Drinking Water
Brackish groundwater is pumped from the on-site well (1) to the reverse osmosis treatment building (2). There, the water is forced by means of high pressure through fine reverse osmosis membranes that keep salt molecules out while allowing water molecules through.

The RO process produces two streams of water: the salt-free “product water” (or “permeate”) and the “concentrate” (or “brine”), which is the wastewater from the process.

The product water is further treated at two stages of the process. Before it leaves the RO building, the product is blended with a small amount of untreated groundwater to enhance taste. The blended product water is pumped to a degassifier (3), which removes carbon dioxide. This increases the pH of the water, which, in turn, reduces the amount of chemicals needed to stabilize the water. After passing through the transfer pump station (4), the water is treated with chlorine and other chemicals to maintain purity and ensure stability. It then is collected in the ground storage tank (5). As the water is needed, a high service pump station (6) moves water through three separate distribution lines for ultimate distribution to homes and businesses served by project partners.

The concentrate is discharged into an existing ditch (7) that flows in to the North Floodway and eventually into Laguna Madre. There it mixes with storm water runoff and return flows from agricultural irrigation, minimizing impacts to area water resources.

The entire process is overseen by on-site operators assisted by an elaborate electronic monitoring system that provides real-time data on process components and water quality. The system (commonly referred to as a Supervisory Control And Data Acquisition – or SCADA – system) is hooked up to a radio transmitter, enabling remote access as well as alerts in case of problems.