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Louisiana City Requires Backflow Valves as a Preventive Measure

DESTREHAN, LA – Since the invention of plumbing, residents of cities in flood-prone areas have faced the same smelly hazard: sewage backflow.


In these low-lying areas, flooding can cause sewage to back up through drain pipes into homes and businesses. The resulting messes can create serious health hazards and resist cleanup efforts.


“Bordered by Lake Pontchartrain and the Mississippi River, the city of Destrehan has experienced problems with sewage coming into homes as a result of heavy rains and frequent flooding,” said L.J. Brady, assistant director for the St. Charles Parish Department of Wastewater. Sewage/septic systems are designed to remove sewage. But if floodwaters enter the system, the sewage can back up into buildings.


“After they put in a parish-wide sewer system in the 1960s, our homes had many problems with flood backups,” Brady said.


Fortunately, the problem has a fairly simple fix. Installing backflow valves protects homes from sewer backups. The valves block pipes temporarily and prevent flow into the house.


The fix works so well that in 1983, the city adopted an ordinance requiring installation of backflow valves in the sewer lines. The law requires all new construction to have backflow valves; the city recommends installation of these valves for older homes. Since that time, all cities in Louisiana have adopted the International Plumbing Code which requires backflow preventers on new construction.


“A lot of occurrences have fallen off since this requirement was implemented,” said Brady. “It’s prevented a lot of damage. We are looking for everything we can do to prevent sewage from coming into the house.”


Four-inch PVC valves are installed in homes, while businesses use six-inch valves. Those measurements pertain to the inside diameters of the valve pipes connected to buildings’ sewage systems and the city sewer system. The PVC material glues easily to pipes, and a valve cover allows access for cleaning.


Savings to families, individuals, and business owners for cleanup of sewage can be significant, especially when considering cleanup costs. The city, which has seen a major reduction in claims, has also realized considerable savings.


Installation is simple and a single valve should cost less than $30. “Any plumber can install the valves,” said Brady.


Although Destrehan has had little trouble with backflow valves, Brady encourages periodic checks with “cleanout as necessary.” He also encourages people who live in older homes to have backflow valves installed, especially those homes built at ground level. “It’s a very simple and relatively inexpensive method of blocking downstream flows,” Brady said. Having more and more backflow valves installed “saves us money by our not having to pay for damages.”

Last updated Jun 3, 2020