Infrastructure
Mountain Pass Highway Bridge
Design and construction of a 280-foot span bridge over challenging mountain terrain with extreme weather considerations
Location
Cascade Range, WA
Completed
2022
Budget
$8M - $10M
Role
Design Engineering Services
Key Performance Indicators
30 months
Completion Time
Completed despite weather delays
HS-25
Design Load
Heavy vehicle loading capacity
280 ft
Span Length
Single continuous span
95/100
Safety Rating
State DOT safety inspection score
Challenges
Extreme mountain conditions required innovative solutions:
- Limited construction season (6 months/year due to snow)
- Steep terrain with difficult access for equipment
- High seismic activity zone requiring advanced design
- Avalanche and rockfall risk mitigation
- Limited construction season (6 months/year due to snow)
- Steep terrain with difficult access for equipment
- High seismic activity zone requiring advanced design
- Avalanche and rockfall risk mitigation
Our Approach
Comprehensive engineering strategy:
1. **Accelerated Construction**: Pre-fabricated steel components for rapid assembly
2. **Geotechnical Analysis**: Extensive soil testing and rock anchor foundation design
3. **Environmental Design**: Wildlife crossing considerations and minimal habitat disruption
4. **Weather Monitoring**: Real-time weather tracking for safe construction windows
1. **Accelerated Construction**: Pre-fabricated steel components for rapid assembly
2. **Geotechnical Analysis**: Extensive soil testing and rock anchor foundation design
3. **Environmental Design**: Wildlife crossing considerations and minimal habitat disruption
4. **Weather Monitoring**: Real-time weather tracking for safe construction windows
Results & Outcomes
Successfully delivered critical infrastructure:
- Reduced travel time by 15 minutes for 8,000 daily vehicles
- 100-year design life with minimal maintenance requirements
- Zero environmental violations during construction
- Enhanced regional connectivity and economic development
- Reduced travel time by 15 minutes for 8,000 daily vehicles
- 100-year design life with minimal maintenance requirements
- Zero environmental violations during construction
- Enhanced regional connectivity and economic development
Project Tags
bridgeinfrastructureseismictransportationsteel
Downloads
Bridge Design Details
5.5 MB
Structural Analysis Report
2.3 MB