The Hampton Roads Sanitation District launched the Sustainable Water Initiative for Tomorrow (SWIFT) to address decades of groundwater depletion in the Potomac Aquifer and Chesapeake Bay watershed, reduce nutrient discharge and strengthen long-term water resiliency in the region.
A key component of this project is the James River Crossing (JRX), a 4.5 mile underwater pipeline beneath the James River, with a capacity to convey more than 45 million gallons of wastewater per day. The pipeline needed to pass beneath the Newport News Shipping Channel, one of the busiest ports in the United States and home to the world’s largest naval base, without disrupting vessel traffic and nearby naval operations, while also limiting environmental impacts.
Collaboration Drives a Record-Setting Pipeline Installation
Design-build allowed the team to prioritize early collaboration to evaluate crossing alternatives and refine the construction approach. By closely integrating engineering and construction expertise, the team was able to propose an alternate alignment using a longer land-to-water horizontal directional drill instead of the standard water-to-water crossing. This eliminated the need for a second marine work platform and reduced associated marine construction and environmental and logistical risks.
The team was also able to coordinate with the pipe manufacturer to design a custom pipe pusher capable of applying up to 750,000 pounds of force to reduce tensile loading during pullback. These innovations resulted in the longest installation of large-diameter high-density polyethylene pipe in the world.
Thanks to these measures, the final cost of the project was reduced by nearly $15 million. Beyond the project, the design-build team provided charitable donations of over $30,000 and documented more than 1,000 volunteer hours supporting environmental initiatives, workforce development and basic community needs.
Taken together with the record-setting pipeline installation, the James River Crossing is a design-build project that demonstrates how early integration of design, construction and specialty expertise can result in innovation, cost-savings and community benefits even in an extremely challenging environment.
Design-Build Team
| Client/Owner: | Hampton Roads Sanitation District |
| Owner Advisor: | AECOM |
| Design-Builder: | Garney |
| General Contractor: | Garney |
| Engineers: | Dewberry |
| Specialty Contractors: | Huxted Trenchless; Seaward Marine Corporation; Michael Baker International; Brierley Associates; Moffatt & Nichol |
| Project Cost: | $139,744,452 |
| Construction Duration: | 24 months |
Photos
Photo Credits: Garney