Lighting an Icon

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Spanning the Mississippi River, the Crescent City Connection is more than just a pair of bridges—it's a defining landmark of New Orleans. The twin cantilever truss spans, originally designed by Modjeski and Masters (M&M), are an essential part of the city’s skyline and infrastructure, plus a symbol of civic pride.

After Hurricane Ida caused widespread electrical damage to the bridge’s decades-old lighting system, the Louisiana Department of Transportation and Development (LADOTD) partnered with M&M once again—this time with the goal of creating a resilient, programmable LED system capable of delivering both visual impact and long-term performance.

From the outset, this was more than a cosmetic upgrade. The new lighting had to integrate seamlessly with existing bridge structures, withstand the coastal environment, and meet a demanding design schedule ahead of the 2025 Super Bowl, all while enhancing safety, visibility, and energy efficiency. The project required close collaboration between structural and electrical design teams to ensure the lighting system achieved long-term durability while meeting the aesthetic and operational demands of the bridge environment.

In order to light the outboard sides of the 3,000-foot-long truss spans, a total of 123 light fixtures were mounted to the lower chord at 63 distinct locations with each site containing between one and three fixtures. Complementing the lower chord lighting, “necklace lights” were located at each panel point along the upper chord and two at the top of each tower. Each necklace light location consisted of four individual one-foot-long linear fixtures. Additionally, 14 fixtures were mounted atop each of the tower piers of the old span with four additional lights on the larger piers for the new bridge. All total between the two bridges, 1,564 fixtures were used in the lighting design.

Each of the LED fixtures can be individually programmed in terms of color, brightness, and timing via a centralized control system, allowing for dynamic lighting scenes that span the length of the bridge or highlight individual segments. This allows for both minimal energy usage and maximum impact, all with a 30-year design life.

Having originally designed both the older (Eastbound) and newer (Westbound) spans of the Crescent City Connection, M&M already had a thorough understanding of the bridge’s construction methods, connection types, and maintenance history.

The structural considerations for the lighting system started with one essential question: how do you mount modern fixtures on aging infrastructure without altering or damaging it?
The design team began with a comprehensive review of historical as-builts and conducted field surveys to assess previous lighting locations. Because the two structures were built using different techniques and materials, riveted connections on the original span and bolted on the newer one, no single solution would fit both bridges. Each span has its own unique geometry, gusset plates, and structural member sizes, requiring the custom design of more than ten different mounting bracket types to ensure proper alignment and performance.

Importantly, clamp-mounted systems used throughout required no drilling and no permanent alterations. To create the clamp-mount, spacers were welded onto strut channels to provide the necessary clearance over existing rivets and bolts. This modification ensured a stable and level bearing surface for the clamps. The modified strut channels were then positioned on opposite sides of the structural member and secured together using threaded rods, forming a rigid clamping assembly. Finally, the new LED fixtures were mounted onto the outward-facing strut channel, completing the clamp-mount installation. This avoided any compromise of the structure’s integrity while allowing for consistent fixture placement.

The original necklace lighting system was mounted on a ¾-inch pipe clamped to the stanchion supporting the hand line. To minimize retrofit labor and preserve existing infrastructure, the new system was engineered for installation using a similar method. By retaining the ¾-inch pipe as the primary support, existing mounting holes could be reused, significantly reducing field modifications.

In the updated design, light fixtures are no longer mounted directly to the support pipe. Instead, four fixtures are affixed to the sides of a square stainless steel tube, through which the new ¾-inch pipe is run and welded to along with the stainless steel end caps. This integrated assembly allows for complete preconstruction at ground level, streamlining the installation process and significantly reducing time and labor required on the bridge deck.

One of the most structurally demanding areas was the upper chord, where cable trays cross over the top. These locations had to be coordinated closely with the field and inspection teams to ensure ongoing access for inspection and maintenance. Spacing of cable tray supports was carefully optimized to meet National Electrical Code requirements while avoiding structural cutouts, especially on the older span.

Any upgrade on a bridge exposed to the elements, and especially one that spans a major river in a hurricane-prone area, must be designed with resilience in mind. Coastal salt, wind vibration, and daily thermal swings in New Orleans were all factored into the material and connection design.

To that end, all mounting members and hardware were specified to be stainless steel for corrosion resistance and durability.

In fact, the new system replaced the previous necklace-style lighting, which used exposed messenger cables and wiring vulnerable to the weather. With this upgrade, most of the cabling is now routed below the deck, along the protected maintenance catwalk. For the upper chords, a new cable tray system offers added protection and organization for the necklace fixture cables. These solutions were a major improvement over the prior system, both in performance and maintainability.

One of the more testing aspects of this project was the timeline. LADOTD wanted the lighting system operational in time for the 2025 Super Bowl, meaning a compressed schedule for design, procurement, and installation.

M&M received notice to proceed in March 2023. Within weeks, we had teams on site to inspect both bridges, including the top chord, catwalk, and pier tops, to identify the best routing paths and mounting conditions. The lighting system was developed with pre-assembled and pre-wired modular units to streamline fieldwork. This minimized the need for site-based fabrication and sped up installation without sacrificing accuracy or quality.

When the initial bid process returned no contractor interest, LADOTD and M&M quickly adapted. Contractors had flagged tight lane closure restrictions and the use of rigid conduit as barriers to meeting the timeline. LADOTD responded by allowing extended lane closures during the summer and approved the use of weatherproof cable trays instead of rigid conduit — a shift that preserved safety and performance standards while significantly improving constructability.

The Crescent City Connection’s new lighting system enhances navigation, visibility, and civic connection. The system features 42 unique programmable themes, letting the city showcase everything from Mardi Gras to game days with vibrant displays that shift in real time. The lights also are remote-operated, allowing quick adjustments in response to mariner or motorist needs.
By illuminating the bridge in colors that reflect the city’s culture, the project honors New Orleans’ heritage while reinforcing the bridge’s status as a critical artery for regional transportation and a cultural landmark.

This project would not have succeeded without extensive coordination between M&M’s electrical, structural and transportation management teams. Each light location was initially chosen by the electrical team, and then the structural team developed mounting configurations based on specific conditions at each location. The field section ensured that no brackets interfered with future inspections or access, which was a critical step for long-term functionality. Additionally, M&M transportation management section, along with subconsultant Ventura Consulting Services LLC, developed the project’s full transportation management plan and revised the traffic control details for the second bid.

Ultimately, this was not just a project about installing new lighting. It was about understanding the nuances of two distinct but related bridge structures, designing with respect to history and integrity, and delivering a solution that’s both technically sound and culturally resonant. ■

About the Author

Jon Gerhart, PE, is an electrical project manager at Modjeski and Masters. He leads the inspection, evaluation, and design of electrical power, control, and lighting systems for all types of fixed and movable bridges, as well as roadway/interchanges. Gerhart served as the project manager for the award-winning Crescent City Connection decorative lighting project.