The Laguna Madre Water District has initiated a seawater desalination pilot project in Port Isabel to establish a potential sustainable water source for South Texas coastal communities. According to a report from the Texas Water Development Board on April 15, 2026, the district is testing technology to convert saltwater from the Port Isabel Channel into potable water to reduce dependence on the declining levels of the Rio Grande.
Driven by a five-year drought and shrinking reservoir levels at Falcon and Amistad, the district is exploring “innovative alternative treatment” methods to diversify its water portfolio. The project involves a temporary pilot intake that utilizes microfiltration and reverse osmosis to remove salt and sediment from seawater.
If successful, the district plans to co-locate a permanent desalination facility at its existing water plant, allowing desalinated seawater to supplement the river water that currently serves residents and tourists in South Padre Island, Port Isabel, and surrounding areas.
According to District Manager Noe Cantu, the Rio Grande’s water supply has gradually declined due to persistent drought conditions, necessitating a shift toward “unlimited” coastal resources.
The pilot project is currently drawing water from the Port Isabel Channel Turning Basin, an area with significant tidal exchange that mimics open Gulf waters. The district is gathering data from this source to demonstrate to the Texas Commission on Environmental Quality (TCEQ) that the alternative treatment meets state drinking water standards.
The desalination process described by David Pettry of NorrisLeal Engineering involves treating the raw water with chemicals and clarifiers, filtering the water to remove fine particles, and then removing salt and producing potable water.
District Engineer Charles Ortiz stated that the utility intends to use reverse osmosis for both its river and seawater sources, which is expected to result in the highest water quality the system has ever produced.
To minimize environmental impact, the project utilizes an existing municipal sewer outfall with diffusers to dilute the saltwater concentrate with treated effluent before returning it to the bay. Environmental surveys conducted for the project indicate that the selected site avoids impacting local seagrasses.
The Kicker “This ensures that we don’t only have to rely on the Rio Grande,” Cantu stated, adding that “seawater desalination, for us, is our answer to be able to provide for generations to come.”