As one of the nation’s fastest‑growing airports, Charlotte Douglas International Airport (CLT) is expanding its terminal, concourses and landside facilities to support record passenger growth –surpassing 53.4 million annual travelers. To accommodate these upgrades, the airport required a new, high‑capacity sanitary sewer system capable of supporting future demand. STV delivered an award‑winning design featuring approximately 2,300 linear feet of new sanitary gravity sewers conveying flow to Charlotte Water’s (CLTWater) Coffey Creek interceptor.
What challenges did STV address?
The project site spans some of CLT’s most active public and operations areas, including roadways, parking lots and the airport’s new passenger access deck. Designing and installing deep sewer infrastructure – up to 40 feet below the active airfield – had to be completed with no disruptions to aircraft movement, terminal operations, traffic control or FAA tower access. Navigating tight utility corridors and maintaining terminal access added significant complexity.
What solutions did STV deliver?
STV designed a system incorporating seven trenchless crossings, enabling installations beneath critical infrastructure without surface disturbance. Key elements include a 300‑foot, 48‑inch steel casing installed 35 feet deep, connecting directly to the Coffey Creek interceptor, and a bored casing threaded between piles of an existing retaining wall. STV provided sewer modeling, utility design, permitting, construction administration and round‑the‑clock coordination with CLT Airport, CLTWater, and FAA stakeholders to ensure seamless airfield and landside operations throughout construction.
How does this project benefit the region?
The improved sewer system supports CLT’s major terminal and concourse expansion programs, prepares the airport for an anticipated 60% increase in passenger traffic and enhances long‑term sustainability. By improving wastewater capacity below one of the busiest hubs in the southeast, the project strengthens airport reliability and supports continued economic growth for the Charlotte region.
Key Stats and Accolades
- 2,300 LF of new gravity sewer
- 7 trenchless crossings
- 300‑ft, 48‑in steel casing installed at 35‑ft depth
- Sewer system up to 40 ft below active airfield
- Supports 60% projected passenger growth
- Recognized for award‑winning design excellence
