Visitors to the annual Bayou Boogaloo festival may have noticed what looks like a new miniature park at the corner of Orleans Avenue and Norman C. Francis Parkway.
However, the site is much more than just an attractive green space. Dips in the planted garden are designed to catch and filter rain, the paved curved path is permeable, allowing water to sink through the cracks into the ground below, and dozens of native trees that will provide shade and take up stormwater.
This small plot of land has on its own added more than 55,800 gallons or 1,100 bathtubs worth of stormwater detention capacity to the drainage system of the Sewerage & Water Board of New Orleans (SWBNO).
Though SWBNO operates one of the largest stormwater pumping systems in the world, this system alone will not be enough to mitigate flooding from the increasingly intense and more frequent storms that New Orleans residents have been experiencing.
“We are one of the many vulnerable cities in the world facing impacts of climate change,” said Ghassan Korban, Executive Director of the Sewerage and Water Board of New Orleans. “Adapting our city to capture stormwater where it falls to relieve the pressure on our drainage system is the only way we can maintain our quality of life in the face of these massive challenges.”
In addition to climate change, New Orleans itself is built on low ground, half below sea level, and consists of a series of connected basins that stretch from the East Bank of the Mississippi River to Lake Pontchartrain. The basins were formed by sinking ground, which is exacerbated by levee systems. Though levees protect city residents from stormwater surges, they also prevent natural processes like rivers depositing sediment into what would be their natural floodplains.
Historically, the SWBNO has focused most efforts on improving what is known as “grey infrastructure.” Grey infrastructure refers to man-made efforts to control stormwater drainage and mitigation, such as pipes, canals, and levees.
Alternatively, green infrastructure imitates nature and uses natural processes to either detain or retain water. There are a wide variety of green methods to either slow down or hold water, including planting trees, bioretention, rain barrels, planter boxes, and permeable pavement.
The Bayou St. John Site is number ten in a series of green infrastructure projects built by SWBNO in the last 10 years. Following the 2014 consent decree issued by the U.S. Environmental Protection Agency, SWBNO pledged 2.5 million dollars to put toward developing and implementing projects that comply with green infrastructure design criteria and involve the community in decision-making and educational outreach.
Bayou St John Green Infrastructure Project completed 2022. Designed by Dana Brown & Associates with contributing partners Burk-Kleinpeter, Adaptation Strategies, RCI, Groundwork NOLA, SOUL and Marais Consultants.
Green infrastructure has important short and long-term benefits to supplement man-made drainage methods. Green methods ease the burden on the city’s 100-year-old drainage systems and reduce localized flooding. Using vegetation and native plants add attractive green spaces and allow floodwater to be held by the root systems, an ability that roofs, streets, and paved areas do not have. Plants and soil also naturally filter polluted stormwater runoff before it enters the canals, lakes, and rivers of the region.
Instead of solely focusing on man-made infrastructure, SWBNO’s five-year Strategic Plan and Green Infrastructure demonstration sites highlight how it is possible to both protect the city from destructive flooding and embrace living with water.
“These sites demonstrate our commitment and leadership – starting a conversation and getting our residents thinking about living with water,” said Director Tyler Antrup, SWBNO District D representative and Tulane School of Architecture Professor. “Green stormwater infrastructure not only beautifies neighborhoods and reduce flooding, but also raises awareness and encourages larger advocacy about how we can collectively adapt to the climate crisis.”
The various green infrastructure projects that SWBNO has undertaken include methods ranging from detention basins to green and blue roof systems to experimental technical studies. Altogether, the ten sites retain and detain over 300,000 gallons of water.
The project at the St. Joseph St. Administration Building in the Central Business District incorporates both green and blue roof technology. The extensive green roof consists of a variety of plants from natives to succulents to herbs managing over 15,000 gallons of rain per storm while the smart drain component of the blue roof closes when it senses rain, detaining additional water.
Two of the other sites are also located on or around school campuses, allowing SWBNO to include educational curricula and community outreach through the projects.
Dorothy Height Charter School, previously known as Paul Habans Charter School, has an installation of an interactive array of stormwater management tools and monitoring stations. Students and members of the public can learn about the role water plays in the ecosystem as well as various methods to collect, transport, and filter stormwater.
Dorothy Height Charter School’s Stormwater Center completed in 2021. Designed by Spackman Mossop Michaels with contributing partners Crescent City Schools, Mullin, SOUL, Greenman Dan and Louisiana Green Corps.
As Ann Wilson, SWBNO’s Chief of Environmental, mentioned at the Height School’s ribbon cutting ceremony, it is not so much about how much water the site holds but about its representation of the future. “This site means you – our future leaders – are learning that green infrastructure can be incorporated into any aspect of any property. It’s a part of your normal day now, and in the future, we know sites like this will be the norm, and not an exception.”