Case Study: Quality Control Failures on Denver Light Rail Expansion (Colorado, 2016)

Project Overview
• Name: Denver RTD Light Rail Expansion
• Location: Denver, Colorado
• Year: 2016
• Project Size: $550 million
• Scope: Extension of light rail lines including track, stations, and signaling systems
• Lead Agencies/Contractors: Regional Transportation District (RTD) /

Category of the Issue, Problem, or Challenge
• Quality Control
• Project Delay

Summary of the Issue, Problem, or Challenge
Multiple instances of poor concrete quality and improper track installation led to rework and delayed system testing.

Root Cause Analysis

• Inadequate quality assurance during concrete batching and placement.
• Lack of sufficient inspection during critical track alignment phases.
• Deficient documentation and verification of materials testing.
• Insufficient training and oversight of subcontractors.

Impacts Due to the Issue, Problem, or Challenge

• Delay of 4 months due to rework and corrective measures.
• Increased costs from material waste and extended labor.
• Reduced confidence from stakeholders and public in project delivery.

Corrective Actions Taken

1. Strengthened on-site quality control staffing and protocols.
2. Implemented stricter material testing and certification requirements.
3. Enhanced training programs for subcontractor crews.
4. Introduced real-time digital quality documentation systems.

Lessons Learned

• Consistent quality control prevents costly rework.
• Training and oversight of subcontractors are critical.
• Real-time documentation helps identify issues early.

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

• Are quality control protocols clearly defined and enforced?
• Is subcontractor work adequately supervised and verified?
• Are testing results documented and reviewed in real time?