SR-520 BRIDGE REMOVAL – LAKE WASHINGTON

SR-520 Bridge Removal – Precision Cutting & Demolition
Penhall was contracted to provide precision cutting and coring for the removal of the SR-520 bridge over Lake Washington in Seattle, WA. This DOT/Infrastructure project required extensive flat sawing, core drilling, wire sawing, wall sawing, and bridge demolition to safely segment the structure for removal.

Scope of Work:

• Precision Cutting – 75,000 LF of flat sawing (6”–34” thick), 6,500 LF of curb sawing
• Core Drilling – 7,000 holes for strategic dismantling
• Wire & Wall Sawing – 16,500 SF of precision cutting
• Bridge Deck Removal – 6,100 LF of bridge deck segmented for safe extraction
• Adaptive Execution – Coordination with evolving demolition sequencing and environmental controls

With temporary trestle bridges and barge-mounted cranes for restricted access, Penhall navigated challenging conditions to ensure the safe, efficient, and timely removal of the bridge while minimizing disruption.