Case Study: Boston Tunnel Waterproofing Project Impacted by Membrane Shortages (2022)

Project Overview
• Name: Boston Central Artery Tunnel Waterproofing
• Location: Boston, Massachusetts
• Year: 2022
• Project Size: $290 million
• Scope: Installation of waterproof membranes and corrosion protection in highway tunnels
• Lead Agencies/Contractors: Massachusetts DOT /

Category of the Issue, Problem, or Challenge
• Supply Chain Disruption
• Waterproofing Materials

Summary of the Issue, Problem, or Challenge
Delays occurred when specialized waterproofing membranes were backordered due to raw material shortages and production limitations at membrane manufacturers.

Root Cause Analysis

• Raw material shortages, particularly polymers and additives essential for membrane production.
• High demand from multiple infrastructure and roofing projects nationwide.
• Limited domestic manufacturing capacity with long lead times.
• Lack of alternate approved membrane suppliers.

Impacts Due to the Issue, Problem, or Challenge
• 3-month delay in tunnel waterproofing work.
• Increased costs due to rush orders and sourcing alternatives (~$1.7 million).
• Potential exposure of tunnel structures to water infiltration risk.

Corrective Actions Taken

1. Approved additional membrane products to increase supply options.
2. Improved procurement forecasting and early ordering procedures.
3. Engaged with suppliers to increase production capacity and prioritize project orders.

Lessons Learned

• Critical specialty materials require early planning and supplier diversification.
• Flexibility in approved materials can alleviate supply risks.
• Proactive communication with manufacturers is essential.

Audit & Prevention: Project Control Questions to Ask on Future Projects to Help Control the Situation

• Are waterproofing material suppliers diversified and qualified?
• Is procurement lead time sufficient to secure materials?
• Are alternative materials pre-approved to mitigate supply disruptions?