Photo courtesy WAMorgan, DepositPhotos.
When the sky opens up and an afternoon deluge swamps neighborhoods across New Orleans, it may seem only logical to want to pump that water out as quickly as possible.
For most of the city’s history, officials and engineers put countless hours and immeasurable effort into doing just that. But, over the past decade, the wisdom of focusing only on pumping stormwater out has been called into question.
Advances in engineering, landscape architecture, and green design have combined with cost-saving techniques pioneered by local green startups. Now, officials are harnessing all that energy to install elements of a green infrastructure across New Orleans.
“In the last 10 years alone, I saw a shift,” said Ghassan Korban, executive director of the New Orleans Sewerage and Water Board. “Here, I think the biggest driver is capturing water where it falls to kind of hold it back from going into the canals, so it doesn’t overwhelm the pumping capacity.”
Nearly every New Orleans citizen has a working knowledge of the city’s pumping capacity. If more than one or two inches of rain falls within a 60-minute span, low-lying areas will flood.
Korban said the mindset shift he has seen focuses on directing rainfall into a wide array of holding areas, from residential rain gardens and cisterns to massive underground tanks designed to fill up as it rains and then slowly release that captured water into the system as the pumps catch up.
“We get a lot of rain, we often get it very quickly, we get these sort of cloudbursts, and it causes flooding, but it also just overtaxes our drainage system,” said Meagan Williams, the urban water program manager with the City of New Orleans Office of Resilience and Sustainability. “Every drop of rain that falls during a rainfall event, for the most part, goes into the drainage system and then gets pumped out into Lake Pontchartrain. It’s an old system, as everyone knows. It was never designed to meet the demands of what it’s having to do right now.”
Williams has helped spearhead a variety of efforts to trap and store rainwater across the city. Korban said his personal favorite green infrastructure site is a recently completed project along Bayou St. John near its intersection with Orleans Avenue.
That project, the 10th green infrastructure project completed so far, can store 58,800 gallons of stormwater using the site’s natural topography. SWBNO Interim Director of Communications Grace Birch said four distinct types of green infrastructure are in play at the site: a bioretention cell, native pond cypress trees planted in fiber soils, a flexible pervious pavement system, and permeable concrete pavers.
“It’s a good size property that we transformed from what I call an ‘ugly lot,’ with grass and garbage, and people parked on it, to now a destination,” Korban said. “We have a long concrete wall for seating, there are beautiful trees everywhere, and in a couple of years from now, we’ll have shade. There are ways to see how water comes in and it gets captured, purified, before it goes back into the system.”
Korban said the Bayou St. John project highlights the city’s green infrastructure in a highly public and easily accessible way. Driving up public engagement and buy in has always been a large part of the city’s efforts, he said.
But the greening of New Orleans has also created a host of new business opportunities. One of the many homegrown success stories is Mastodonte, a New Orleans-based stormwater management startup with over a decade of experience in the local market.
Mastodonte founders and co-owners Arien Hall and Luisa Abballe both have backgrounds and formal training in fine arts. They served with AmeriCorps in New Orleans, an experience that laid the groundwork for their current work.
Abballe said she knew absolutely nothing about stormwater management until a roommate started discussing the installation of a French drain system at their shared home.
“When we first started, we had houses that experienced repeated flooding,” Abballe said. “It just kind of expanded from there, where we just created this budget, and they let us run with the project, and it worked.”
In 2019, Mastodonte took home the $10,000 first-place prize at the 2019 Water Challenge presented by Greater New Orleans Foundation, nonprofit incubator Propeller’s annual pitch competition for entrepreneurs.
Often, the five-member team at Mastodonte begins projects by breaking up existing concrete driveways before building back with water-permeable concrete or pavers. Other projects involve digging bioswales like the ones at the Bayou St. John site.
“By creating essentially more water storage on your property, we capture that water as close to where it’s falling as possible, instead of pumping it and creating a more overloaded conventional system,” Hall said.
Hall, a professional violinist, said she was excited to learn new hard skills and get her hands dirty while helping her community.
“When I found out that I could get into the green sector, it was just very rewarding to me,” Hall said. “I thought it was something that I could do to help my community. I saw the sense of stewardship, essentially, and it kind of went hand in hand with the work that I was doing rebuilding homes with AmeriCorps after Katrina.”
Korban said that desire to pitch in and help against what can feel like insurmountable odds in a city mostly below sea level is the key to the ongoing success of the city’s green infrastructure initiatives.
“I see more and more small rain gardens being built, in front lawns and back lawns,” he said. “You see permeable pavement happening, driveways, parking lots. There’s definitely a culture of ‘I want to be part of the solution,’ and in many cases, people can see the benefit of that. I don’t see that changing. I think we’re going in the right direction.”
Green Roofs, Living Walls, and Green Infastructure Read More