To Prevent Flooding in New Orleans, Holding Water Rather Than Pumping It

Beau Evans reports on efforts in New Orleans to address flood threats by shifting away from pumping water to retaining it. “Doing so would ease the burden placed on pumps and underground drainage pipes during storms, and more water stored over time would help replenish the city's groundwater levels to counteract the sinking effects of subsidence,” says Evans.

The 2013 Urban Water Plan described the many challenges New Orleans faces in dealing with stormwater. “Perhaps more concisely than any other document, it dissects the combined influences of the city's low-lying topography, subsidence, impervious surfaces and the constant threat of heavy rains that often overwhelm the drainage system,” reports Evans.

Evans says the city has been slow in getting projects off the ground that use the retention-hold approach, with a backlog of about $250 million in projects when Mayor LaToya Cantrell came on board in the spring. A series of green infrastructure projects to contain water are planned for the next several months, including construction of retention ponds, rain gardens, and permeable pavement.