New Orleans needs a better approach to storm runoff, experts say

The current tactic of moving storm water out of the city as quickly as possible needs to change, and now is the time to change it, according to three experts who spoke at a workshop Wednesday devoted to exploring how other U.S. cities are turning water challenges into water assets.

The workshop was the first in a series of five focused on strategies in urban water management hosted by the Greater New Orleans Foundation in partnership with the Urban Institute and more than 30 other organizations.

New Orleans wasn’t always a below sea-level bowl, said Mark Davis, director of the Institute on Water Resources Law and Policy at the Tulane University Law School.

“We built the bowl,” Davis said, by drawing too much water out of the city. “Every new pump structure creates tomorrow’s subsidence and tomorrow’s risk,” he said.

“When a city is in a bowl, water management is flood protection,” said Jeff Thomas, principal of Thomas Strategies, LLC and a lawyer in New Orleans.

Thomas described storm water management, and drainage, as the third line of defense, behind levees, the second, and coastal restoration, the first. Allowing water to be absorbed into the spongy ground mitigates subsidence, he said.

Flooding caused by rain is a different beast from storm surge, Thomas said, and is particularly important in the third-rainiest city in the country.

“We have to see a shift in the way New Orleans approaches water management,” Davis said.

Davis also noted that water management is intrinsically linked to flood insurance rates, a battle underway as residents face the prospect of a hike in the federal program’s rates.

Davis also stressed the linkage between prosperity and proximity to water, as cities and states facing water shortages battle over the country’s system of rivers, including the Mississippi. In terms of conserving existing water supplies, he said, “storm water is a great place to start.”

While the Netherlands is hailed as the world’s expert, mirroring their system can be a “paralyzing” prospect, Thomas said. A better approach is to be incremental about improvements, he said.

Borrowing from other U.S. cities also provides a better model for funding projects, he said.

A national perspective was brought to the conversation by Noah Garrison, an attorney for the Natural Resources Defense Council.

New Orleans has unique and increased challenges, but Garrison said many of the fundamental issues are the same for other cities.

Garrison showed images of the change in urban landscapes over time from green space to impervious paved surfaces, leaving water with nowhere to go but downhill and into surrounding bodies of water, often carrying pollutants with it.

Green infrastructure and low-impact development works everywhere, he said.

Garrison showed pictures of roofs covered in a few inches of soil, grassy lawns and vegetation — an approach that not only absorbs and reduces runoff but also cuts energy costs for cooling the building beneath.

For cities facing shortages, retaining water can provide a backup water supply, Garrison said.

Thomas said the city should look at whether every viable public and private space is being enlisted to absorb water, hold water or at least direct it away from homes and businesses and slow it down before it enters the frequently overwhelmed drainage and pumping system.

As the neutral grounds of several major streets are currently under construction, Thomas said rebuilding them more as a basin than a dome would be an easy, and already funded, place to start.

Thomas said in his experience, FEMA and the Army Corps of Engineers have been willing and flexible when it comes to modifying projects, but the initiative has to come from the city.

During a question-and-answer period, Executive Director of the Sewerage and Water Board Marcia St. Martin spoke up when asked whether the city is being proactive in rebuilding better.

“We have asked, and the corps said yes,” she said, referring to neutral ground projects. “People will be pleased.’’

Garrison talked about ways other cities mandate and provide incentives for better practices, such as drainage fees and setting water retention standards for new developments.

“We have to become more purpose driven,’’ Davis said, and less driven by compliance. Current rules and regulations — many woefully outdated – don’t necessarily define wise choices, he said.

Many projects and innovative approaches can add aesthetic value, raise property values and create jobs, Thomas said.

“It’s time to put the sexy back in drainage,” Thomas said. “In a city in a bowl, we have no choice.”