Case Study: Delay Due to Design Changes on Dallas Flood Control Project (Texas, 2018)
Project Overview
• Name: Dallas Flood Control and Drainage Improvements
• Location: Dallas, Texas
• Year: 2018
• Project Size: $350 million
• Scope: Construction of flood control channels and stormwater infrastructure
• Lead Agencies/Contractors: City of Dallas /
Category of the Issue, Problem, or Challenge
• Design / Scope Change
• Project Delay
Summary of the Issue, Problem, or Challenge
Significant design changes prompted by updated hydrological data led to rework and schedule setbacks.
Root Cause Analysis
- Incomplete initial hydrological modeling.
- New flood data released mid-construction requiring scope changes.
- Inadequate design flexibility to accommodate changes.
- Slow approval of revised designs and contractor change orders.
Impacts Due to the Issue, Problem, or Challenge
- Delay of 6 months.
- Cost increases from rework and extended mobilization.
- Contractor claims and disputes over schedule impacts.
Corrective Actions Taken
- Improved hydrological studies and modeling in early project phases.
- Established design contingency allowances and flexible contract terms.
- Streamlined design approval and change order processes.
- Enhanced communication and collaboration between design and construction teams.
Lessons Learned
- Accurate and complete initial data reduces mid-project design changes.
- Flexible contracts and contingency planning accommodate unavoidable changes.
- Timely approval processes minimize delay impacts.
Audit & Prevention: Project Control Questions to Ask on Future Projects to Help Control the Situation
- Are baseline data and models robust and validated?
- Is there contractual flexibility for design changes?
- Are design revisions and approvals expedited?