Project Overview

• Concrete CSO basins ranging from 11,000 to nearly 400,000 square feet
• Extend service life by 20 years
• Design-build project delivery
• More than 43,000 labor hours without an OSHA-recordable or lost-time incident
• Received ICRI Award of Merit, Water Structures

The Great Lakes Water Authority (GLWA) faced aging, deteriorating concrete infrastructure across nine Combined Sewer Overflow (CSO) facilities serving Detroit and surrounding communities. These critical facilities store and pre-treat stormwater during wet weather events, helping reduce environmental impacts on surrounding waterways. To extend the facilities’ service life by 20 years while maintaining operations, PULLMAN delivered a comprehensive rehabilitation program.

Using advanced technologies, including laser scanning, 360-degree imagery, and drone inspections, existing conditions were documented and a risk-prioritized repair plan was developed. A design-build approach integrated engineering, constructability, and cost considerations to prioritize repairs based on safety, structural condition, and operational risk. Work was carefully sequenced around weather forecasts and seasonal flow patterns to keep the facilities operational and ready to manage stormwater throughout construction.

The project scope included concrete and masonry repairs, crack injections, reinforcing steel repairs, and safety improvements. Specialized materials and adaptive construction methods, including heated curing blankets, enabled durable repairs in temperatures as low as 20°F.

The rehabilitation improved the reliability of all nine CSO facilities and extended their expected service life. Completed without any unplanned discharges, environmental incidents, or service interruptions, the project demonstrates how technology, risk-informed planning, and collaborative design-build delivery can rehabilitate critical infrastructure while maintaining uninterrupted public service.