NAPOLEONVILLE, LA – When the waters start to rise, the pumps get going in low-lying Assumption Parish — thanks to a mitigation measure that has saved the parish from flooding time and time again.
Located 60 miles west of New Orleans, the parish is nestled along Bayou Lafourche just south of the Mississippi River. Its southernmost tip sits about 25 miles from the Gulf of Mexico. Miles upon miles of lakes and bayous meander through the parish. It’s most vulnerable areas include Bayou L’Ourse and the low-lying areas of Pierre Part, which has the largest portion of the parish’s 23,000 inhabitants.
Starting in the 1970s, parish authorities had drainage pumps installed to deal with Mississippi River flooding and deluges from heavy rains, tropical storms, and hurricanes. Today, Assumption Parish has 66 strategically located pumping stations standing ready when storms strike.
“We usually have problems every May because it is the high-water month,” said Bobby Naquin, parish manager.
The network of pumps sucks up flood water and diverts it to Lake Verret, a seven-mile-long swamp that lies at the western edge of the parish. Along the way, the water rushes through pipes ranging in diameter from 8 inches to 24 inches. “There even is one drainage pump with 32-inch pipes,” Naquin said.
The earliest pumps used diesel fuel, but electricity powers most of their replacements. The electric-powered systems start up automatically, while people must unlock the gas and propane generators to fire them up when rains begin to pool into significant amounts of water. All of the pumps have automatic shutoff systems, and many of the pump stations have backup generators.
Naquin said a 12-inch pump station with 8-foot long pipes costs about $25,000 to purchase and install, with larger stations costing far more. Maintenance requires ongoing attention, with pump motors usually lasting 10 years, and the pumps themselves lasting about 20 years, Naquin said.
Since their installation, Assumption Parish’s pumps have proved invaluable. Elevated above the highest flood marks, the pumps ensured the parish had “minimal damage” during hurricanes Katrina and Rita and the 2011 Mississippi River floods, Naquin said.
Even so, Hurricane Isaac’s prolonged torrential rains posed a unique challenge. “It rained and rained, and the pumps ran and ran,” said Naquin. The pumps again saved the day. “The results again were very little flooding compared to some areas due the efficiency of the pumps.”
Pumping stations are common in southern Louisiana to protect people and property from floods caused by major storms.
“Drainage pump stations play a critical role in flood prevention,” noted Jim Stark, former director of FEMA’s then-Transitional Recovery Office in New Orleans.