Fixing a crumbling highway artery while keeping 90,000 daily commuters moving sounds impossible. Yet that is exactly what planners face on a critical mid-century river crossing near the nation's capital.
The northbound Interstate 395 bridge over the Potomac River is approaching its mid-seventies, and it is showing its age. Built back in 1950, this four-lane workhorse connects Arlington, Virginia, with Washington, D.C., anchoring a vital five-structure transit network. Now, it is landing a massive $114 million rehabilitation. Instead of dragging out commuter misery over years of lane closures, engineers are planning a radical move. They will swap out a major section of the bridge during a single 56-hour weekend window.
The Problem with Aging Movable Spans
Most older bridges feature movable sections to let tall commercial vessels pass underneath. On this specific span, that meant a 175-foot, double-leaf bascule mechanism. Over decades, mechanical components wear down, maintenance costs spike, and the constant opening and closing creates structural bottlenecks.
Modern traffic patterns don't require the same marine clearance frequency here. Officials decided to ditch the movable mechanism entirely. Engineers will replace it with a brand-new fixed structure. Doing this the traditional way would mean months of lane shutdowns, angry drivers, and logistics nightmares. Civil contractors had to find a smarter workaround.
How to Float a Bridge Span in 56 Hours
Skanska USA Civil is leading the design-build charge for the District Department of Transportation, partnering with design firms like AECOM and Genesis Structures. Instead of building the replacement piece directly over the water—which would snarl traffic for months—they are taking an assembly-line approach.
The entire new fixed span is being constructed entirely beside the existing bridge. When installation weekend arrives, specialized marine equipment and heavy rigging crews will step in. They will lift, transport, and float the massive new section straight into position during a tight 56-hour closure.
It is high-stakes engineering. If anything goes wrong with the floating alignment or rigging gear, thousands of Monday morning commuters will face immediate gridlock. Precision is everything.
What Else the $114 Million Buys
A quick fix on the movable section isn't enough to save a 1950s structure. The overhaul goes much deeper than just the headline-grabbing float operation.
Crews are scheduled to tackle several major upgrades before the project wraps up around fall 2029:
- Upgrading vessel protection systems surrounding the bascule piers to handle modern vessel collision standards.
- Replacing outdated bridge barriers with impact-resistant modern designs.
- Repairing the superstructures and substructures of the approach spans.
- Overhauling overhead sign structures, damaged lighting, and essential drainage systems.
Managing a Massive Construction Zone
If you think one major project in the area is chaotic, consider the neighborhood. This bridge sits directly beside another massive infrastructure effort: the roughly $1 billion Long Bridge North project, managed by Skanska and FlatironDragados to expand local rail capacity.
The Arlington-Washington river corridor is basically turning into one giant heavy-civil construction site through the end of the decade. Subcontractors specializing in marine work, structural steel, and traffic control have their hands full balancing both projects simultaneously.
If you travel through this corridor regularly, expect heavy construction activity to dominate the landscape for the next few years. Pay attention to early project alerts, watch for sudden weekend lane restrictions, and expect detours when that 56-hour float window finally arrives.
