Case Study: Dulles Metrorail Phase 2 – Scope Creep and Change Order Complexity (2019)
Project Overview
• Name: Dulles Metrorail Extension Phase 2
• Location: Northern Virginia
• Year: 2019
• Project Size: $2.8 billion
• Scope: 11.4-mile extension of the Washington Metro’s Silver Line
• Lead Agencies/Contractors: Metropolitan Washington Airports Authority (MWAA) /
Category of the Issue, Problem, or Challenge
• Contract Change Order
• Scope Management
Summary of the Issue, Problem, or Challenge
Midway through construction, the project faced significant change orders stemming from owner-driven scope additions (e.g., station design changes, updated fire safety systems, and stormwater improvements). The design-build contract did not effectively limit owner-initiated changes, causing major budget and timeline impacts.
Root Cause Analysis
- Inadequate change control processes in the design-build agreement
- Design not fully settled at NTP, leading to iterative design changes
- Owner modifications without full cost/time impact assessment
- Ineffective communication between design team and field crews
Impacts Due to the Issue, Problem, or Challenge
• Over 13 months of cumulative delay
• Nearly $275 million in change order costs
• Public criticism for lack of scope control and oversight
Corrective Actions Taken
- Rewritten owner review/approval timelines to limit late-stage changes
- Stricter scope freeze protocols before final design lock-in
- Introduced a Change Control Board with veto power over discretionary scope growth
- Required quantified impact studies for all future owner-requested changes
Lessons Learned
- Design-build contracts must balance flexibility with change discipline
- Owner-driven changes require strict governance
- Scope freeze points should be enforced contractually
- Transparent change order tracking builds accountability
Audit & Prevention: Project Control Questions to Ask on Future Projects to Help Control the Situation
- Are owner changes subject to quantified impact review?
- Is a clear governance model in place for scope growth?
- Are there contractual limits on discretionary changes post-NTP?
- Are design decisions locked in before major procurement?