Case Study: Seattle Light Rail Extension Delayed by Precast Concrete Panel Shortages (2023)
Project Overview
• Name: Seattle Link Light Rail Expansion
• Location: Seattle, Washington
• Year: 2023
• Project Size: $1.2 billion
• Scope: Extension of elevated and underground light rail infrastructure with precast concrete panel installation
• Lead Agencies/Contractors: Sound Transit /
Category of the Issue, Problem, or Challenge
• Supply Chain Disruption
• Precast Concrete Materials
Summary of the Issue, Problem, or Challenge
The project experienced schedule slippage when precast concrete panels faced delayed delivery due to factory production backlogs and raw material (cement and aggregate) shortages exacerbated by regional demand spikes.
Root Cause Analysis
- High regional demand for precast concrete elements from multiple projects.
- Supply constraints on key raw materials (cement and aggregates).
- Limited precast plant capacity and no contingency suppliers initially planned.
- Procurement delays and insufficient lead time for manufacturing.
Impacts Due to the Issue, Problem, or Challenge
• 4-month delay in installation of elevated guideway segments.
• Increased costs due to expedited manufacturing and alternative sourcing (~$3.2 million).
• Project schedule impacts on track installation and system commissioning.
Corrective Actions Taken
- Secured additional precast manufacturing capacity through subcontractor agreements.
- Improved procurement planning with longer lead times and material forecasting.
- Developed strategic stockpiling of critical raw materials and components.
Lessons Learned
- Precast concrete supply chains require advance scheduling and contingency plans.
- Regional market dynamics can heavily impact raw material availability.
- Multi-supplier strategies reduce production bottlenecks.
Audit & Prevention: Project Control Questions to Ask on Future Projects to Help Control the Situation
- Are precast panel production schedules aligned with project milestones?
- Are multiple manufacturing plants engaged to spread risk?
- Is raw material availability monitored and secured in advance?