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

  1. Rewritten owner review/approval timelines to limit late-stage changes
  2. Stricter scope freeze protocols before final design lock-in
  3. Introduced a Change Control Board with veto power over discretionary scope growth
  4. 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?
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