The Louisiana Department of Health (LDH) has lifted the “do not use” water advisory for an area served by the Walnut Bayou Water System in Madison Parish after drinking water was exposed to the chemical paraquat last week.

 Testing results confirmed Thursday that no paraquat remains in the water system. Walnut Bayou Water System conducted extensive flushing, removing the paraquat from the system, LDH officials reported.

Now that the paraquat is out of the distribution system, customers need to flush their home systems, they said.

• All customers should flush hot water taps for 15 minutes, then cold water taps for 5 to 10 minutes.
• Flush ice makers, dishwashers and washing machines as well. 
• Flush toilets at least one time.
• After discarding any ice currently in the icemaker, allow the container to fill completely, then discard the ice and clean the container before replacing.
• If the refrigerator has a cold water dispenser, replace the filter and flush the dispenser for 5 minutes. 
• For dishwashers and washing machines, after flushing hot water taps, allow dishwashers and washing machines to run for one hot cycle and one cold cycle while empty.

LDH said residents may need to flush over several cycles if they continue to smell a chemical odor or have discolored water. 

“The chemical odor is added to paraquat to warn of its presence,” LDH said in a statement. “The odor itself does not cause health problems. If the odor persists as you flush your systems, open windows and doors and run the HVAC system, window units, and/or fans to create air circulation and help with ventilation to dispel the odor.”

LDH said the amount of paraquat in the system will not cause corrosion or other damage to pipes and it does not linger. Once the chemical is flushed out of the water system and household lines, paraquat will no longer be present. This means the drinking water will be safe to use and consume.

Paraquat is a toxic herbicide primarily used for weed control that should not be consumed. Individuals should avoid bathing, handwashing and washing clothes with water contaminated with paraquat, as the chemical can also be absorbed through the skin. Infants, children and people with respiratory illness are most at risk of harmful health effects of paraquat consumption or exposure.

Paraquat testing of the home system is not necessary once home flushing is completed and ventilation of the smell has dissipated; however, if someone wants a laboratory to test their water, they should use a lab certified to perform paraquat analysis and ship their samples to the lab. Eurofins Scientific (in California and Indiana), SGS (in Colorado) and Pace Analytics can run paraquat tests.

Residents with additional questions or who need bottled water may call the Walnut Bayou Water Association Office at 318-574-2463.