Transforming one of the last, relatively undeveloped sections of urban acreage in New Orleans into a modern neighborhood that can rival the city’s historic French Quarter or Garden District starts with groundwork—and in the case of the city’s River District, underground work in the shape of a massive underground stormwater vault.

The River District hopes to construct a new New Orleans neighborhood that is storm-ready, sustainable, multimodal and integrated with storied neighborhoods nearby, says the project team, which includes the Ernest N. Morial New Orleans Exhibition Hall Authority Board and River District Neighborhood Investors.

More than $30 million in infrastructure work for the almost 40-acre mixed-use development began in June 2024, says Tara Hernandez, founder and president of JCH Properties+, and investor partner in the River District project.

That work involved installing the districtwide stormwater system, along with utility work that includes power lines, water and fiber, she says.

The Ernest N. Morial Convention Center is adjacent to the 39-acre, six-parcel project area. The land is owned by the exhibition hall authority, which launched the project in September 2019 to link the city’s Warehouse and Lower Garden districts with the Riverfront and Convention Center via the new mixed-use development.

It is a signature project for architect Gensler in its south central region. The firm’s work on River District dates to 2020, when the firm began work on a master plan for the Convention Center Neighborhood overlay district, says Tiger Lyon, Gensler design director and regional practice area leader for office development.

The first big push for the Gensler team was to create design guidelines for the development. With contractors Boh Bros. Construction and Broadmoor, it is currently working to install infrastructure framework, which is presenting some old New Orleans-type complications.

The 92,000-cu-ft modular stormwater retention vault was designed as if all of the River District project’s six parcels were to be developed to the maximum allowable area of impervious surfaces.
Rendering courtesy Gensler/River District New Orleans

Going With the Flow

With the Mississippi River very close to the southern boundary of the district, a high water table is presenting challenges for the project team, which is responding with one of the largest modular stormwater retention vaults in the state, capable of handling runoff for the entire 39 acres.

Work on the stormwater vault finished in November 2024, says Hernandez, adding that it is one of the largest modular systems in the state and will provide vital protection from flooding, erosion and other environmental damage.

Similar systems have been used in Texas for large-scale developments, but the New Orleans project is among the first in Louisiana at this scale. “Living with water in New Orleans is a challenge for any development and one that the River District has been tackling with care from the beginning,” she says.

Overseeing vault installation was Ruhan Isim, vice president of engineering and technical services at New Orleans-based ILSI Engineering, the project’s civil engineer.

He says work was completed just before the end of last year on the 92,000-cu-ft stormwater vault. It can collect the first 1.25 in. of rainfall across the site, calculated as if each of the six parcels were developed to the maximum allowable amount of impervious surfaces per the city code. With the current levels of impervious surfaces planned, the development would only be required to supply about 65,000 cu ft of storage, he adds.

“We assume all of those six parcels are going to be 95% runoff, and based on that, we make this calculation,” Isim says. “Some places are going to be very green, and we still assume those are going to be concrete [for vault capacity calculation].”

The completed vault is 188 ft long, 65 ft wide and 8 ft, 4 in. high, with 6-in.-thick concrete walls buried under 24 in. of dirt, he says.

Manufactured by Illinois-based StormTrap, the modular vault is a cost-effective option and a good choice for a site with limited space as well as for one with a high volume of stormwater, Isim says. This is the first StormTrap to be installed in the state.

“The good thing is that because of the volume, the cost per cubic foot is much cheaper,” he says, adding that the modules do not require much preparation other than a regular concrete slab or stone base. Excavation of the area required paying attention to the river’s elevation and necessitated much dewatering in the soft soils.

In this case, about 1 ft of No. 57 stone was laid first, followed by a PVC geogrid, geotextile fabric, a 6-in. concrete slab and 6 in. of additional stone on which the modules were placed.

Two 24-in. pipes on top of the system, set at a steep grade, allow for discharge if the water level reaches that elevation. The retention vault is separate from the stormwater system on district streets, which feature a more conventional system with 64-in. pipes meeting at a box culvert on Convention Center Boulevard at Henderson Street, Isim says.

Groundwater is at a high elevation in the area, given the river’s close proximity, Isim notes. “You dig two feet, you have water,” he says.

That closeness and its effect on the water table provided logistical challenges for the team as well, Lyon notes.

“The schedule can be jeopardized if the river gets over a certain height and the water table rises,” he says. “It shuts down construction and operation until the water level goes down below the target threshold.”

The retention vault is set in the heart of the district, Lyon notes, adjacent to the office building site and placed below a public park near the bus rapid transit stop. The system also provides flexibility as project development progresses, with opportunities for additions like pocket parks.

“Because we don’t have to deal with [water retention in each separate parcel], we’re [able to do] districtwide parking and parking garages,” he says. To facilitate parking for the office building, the initial concept was revised to include a podium.

The project’s first vertical construction is a Class A office building for Shell Oil that includes impact-resistant glazing and other features to withstand damage from hurricanes.
Rendering courtesy Gensler/Cypress Equities

An Office Revival

The first vertical construction, breaking ground in early February, is the roughly 140,000-sq-ft Class A office tower that will serve as Shell Oil’s headquarters for Gulf Coast operations. It also is the first new Class A office building to be constructed in the city since 1989, Lyon says.

What was originally planned as a multitenant office building has become a build-to-suit for Shell, an example of different scales of tenant commercial and office space that the River District hopes to provide in New Orleans.

The building is designed for resistance to hurricanes and flooding, Lyon adds, noting that during Hurricane Katrina in 2005, the nearby Garden District was one of the few local areas that had relatively little flooding.

All buildings in the River District will be elevated 4 ft above base flood elevation. Gensler is working with local landscape architect SMM on a plan to transition from the road level to the buildings, since in many places the project aim is for a close-to-the-street urban design.

The Shell building will have redundancy in 5G fiber and power, with backup generators for emergency operation and impact-rated glazing. The River District aims to ensure central plant-based utility solutions that include backup power energy production and reduced emissions, Hernandez says.

Lyon says the project has two options for power redundancy: tying into the existing central utility plant at the convention center or rehabilitating the historic Market Street power plant just outside the project area. Gensler has developed initial concepts to transform the facility into a neighborhood cogeneration facility as well as an entertainment anchor.

Hernandez says the power plant is owned separately, with its development being managed by another team, although all are part of the River District Neighborhood Investors team.

“We are excited to witness the reanimation of that historic landmark,” she says.

The office building represents the first phase of construction for the district, Lyon notes, to be followed by affordable housing projects that make up the second phase. Plans call for half of the planned 900 residential units to be earmarked for affordable housing.

The goal is a blended district, with cultural elements and sports elements, he says, noting various ideas that have been floated for additions such as a civil rights museum or museum of local music.

“We are one of the most walkable cities in the country, and we are prioritizing opportunities to improve multimodal transit and transportation infrastructure,” Hernandez says. “The River District team is considering how the city flows and functions and how that pace needs to be integrated at each step of our development.”