close menu
This website uses cookies to store your accessibility preferences. No personal / identifying information is stored. More info.

Gulf Coast Water Authority Chlorine Maintenance April 13-27

Gulf Coast Water Authority Announces Annual Change to Water Disinfection
The Gulf Coast Water Authority (GCWA) will temporarily change its water disinfection process April 13-27, 2020. This annual routine maintenance practice is necessary to maintain water systems operated by GCWA and the Galveston County communities it serves. The temporary change from a combination of chlorine and ammonia (chloramine) to chlorine helps to prevent taste and odor problems that can occur during the hottest months of the year.

GCWA’s Thomas Mackey Water Treatment Plant provides drinking water to a number of communities throughout Galveston County. All communities except League City, Friendswood, Seabrook and Bolivar will be included in the chlorine maintenance. As part of the disinfection process, municipalities and water districts will flush their systems by opening fire hydrants. Water users may notice some water discoloration or cloudiness. These conditions are harmless and temporary and should be remedied by fire hydrant flushing. The chlorine maintenance process has not been linked to any adverse health effects. While the levels of chlorine in the water during the temporary disinfectant change are consistent with levels found in the water throughout the year, the temporary suspension of ammonia can make the chlorine odor more noticeable. 

Owners of fish and reptiles should follow standard water treatments using products that remove both chlorine and chloramine from the water.
Dialysis centers will continue to treat the water to remove all chemical disinfectants, including chlorine and chloramine, before the water is used for dialysis. Home dialysis users should consult their machine manufacturers for instructions on how to properly treat their water before use.
Water users can contact their local municipality or water district for questions about the water system disinfection.

GCWA is a special water district that provides water for industry, agriculture and municipalities in Brazoria, Fort Bend and Galveston counties. Read more at and follow GCWA on Facebook and Twitter.

Why does drinking water need to be disinfected?
The disinfection of water has played a critical role in improving drinking water quality in
the United States. It has been standard practice in the U.S. for more than a century. In fact,
American drinking water supplies are among the safest in the world, according to the
Centers of Disease Control and Prevention.

What are drinking water requirements in Texas and who regulates water quality?
Public water systems are required to disinfect water prior to it entering the distribution
system that carries it through pipes to customers. The Texas Commission on Environmental
Quality regulates drinking water in the state.

Where does drinking water for Galveston County communities served by GCWA come from?
Water from the Brazos River Basin is treated at the Gulf Coast Water Authority’s water
treatment plant in Texas City. The plant has the capacity to treat more than 50 million
gallons of water a day to serve approximately 190,000 consumers in Galveston County.

What kind of water testing is done routinely and what will be done during the maintenance period?
The water treatment plant staff tests its water every 4 hours, as mandated by the federal
Safe Drinking Water Act. This level of testing will continue throughout the maintenance

What is the list of cities impacted?
Municipalities and water utilities include:
o Bacliff MUD
o Bayview MUD
o Bayou Vista (Galveston County MUD #12)
o Dickinson (Galveston County WCID #1)
o Galveston Island
o Hitchcock
o Kemah, Clear Lake Shores (Galveston County WCID #8)
o La Marque
o San Leon MUD
o Santa Fe (Galveston County WCID #1)
o Texas City
o Tiki Island (GCFWSD #6)

What is chloramine and why does the GCWA use it?
Chloramine is an effective disinfectant that works over a long period of time, particularly in
areas with high temperatures like Texas.