Safeguarding Dallas Neighborhoods: The Mill Creek Drainage Relief Tunnel
Project at a glance
- Location: Dallas, Texas
- Project type: Infrastructure
- Estimated Completion: 2027
- Amrize solution: OneCem cement
- Key partners: Southland Holdings
In brief
Deep beneath the streets of Dallas, construction teams are building one of North America’s largest stormwater tunnels. This massive structure sits nearly 200 feet below the city and is wide enough to accommodate a four-story building.
Once crews finish the 5.3-mile Mill Creek Drainage Relief Tunnel, it will protect almost 2,200 homes, businesses, and critical infrastructure from destructive floods that have long challenged Dallas. The tunnel will hold an enormous amount of water — 160 million gallons, equivalent to more than 240 Olympic-sized swimming pools — directing it safely downstream to the Trinity River.
The ambition: A tunnel built to outlast Dallas floods
The Saf-T-Lift carries crews deep below Dallas to access the tunnel, while underground rail systems move material to where it is needed for construction.
The Saf-T-Lift carries crews deep below Dallas to access the tunnel, while underground rail systems move material to where it is needed for construction.
The Saf-T-Lift carries crews deep below Dallas to access the tunnel, while underground rail systems move material to where it is needed for construction.
Beyond flood protection, the tunnel is designed to support new parks, urban development, and resilient growth across Dallas. To make this vision a reality, Southland Holdings, the general contractor for this project, needed a partner who could provide:
- Consistent high-performance cement to keep continuous underground construction moving
- Technical expertise to meet demanding durability and hydraulic specifications
- A steady supply to keep the project on its strict schedule
The solution: Cement engineered for 200 feet underground
Formwork inside the tunnel supports the installation of the Cast-in-Place (CIP) concrete liner, with concrete placed behind the framework to create the tunnel’s finished structure.
Amrize worked closely with Southland Holdings to achieve these goals. Cement has long been the building block of America’s infrastructure, and for the Mill Creek tunnel, it was critical to get the mix right. Amrize supplied approximately 45,000 tons of OneCem cement, a Made in America-labeled product engineered for strength and long-lasting performance, backed by a reliable local-to-local supply network.
“The quality of the cement supplied by Amrize is at the heart of this operation. It’s what delivers the strength and performance we need to get the job done right.”
Key contributions included:
- Advanced building materials: Ensuring dependable cement quality and consistency across batches poured throughout the tunnel’s construction
- Technical partnership: Optimizing cement specifications for the tunnel's demanding underground environment
- Proven results: Consistently exceeded strength expectations with cement achieving higher PSI than required
- Dependable supply chain: Drawing on Amrize’s network and nearby plant to deliver quality-checked batches before being transported by underground rail 200 feet below
The results: A path to safer, more resilient communities
The massive tunnel will run beneath Dallas, providing 100-year flood protection while creating opportunities for future parks, urban development, and resilient infrastructure.
Amrize’s cement has provided the durability and reliability required for continuous tunnel construction. As the project progresses toward its anticipated 2027 completion, the Mill Creek tunnel will safeguard Dallas communities from flooding and facilitate future development, demonstrating how advanced materials and technical expertise can enhance critical infrastructure across North America.
