Hazard Mitigation Retrofit Power Plant Program at the Carrollton Water Treatment Plant

Trigon was a major subcontractor (23% of contract) for this $200M hazard mitigation program to retrofit a unique power plant owned and operated by the S&WB that produces power at 25 Hertz and supplies critical facilities such as water, wastewater and drainage pump stations and treatment plants. This work was a result of damages caused by Hurricane Katrina in 2005. The work included, for example, repairs and upgrades to generators, fuel tanks, boilers, turbines, and electrical instrumentation & controls infrastructure, as well as ancillary facilities at a major water treatment plant complex where the power plant is co-located.

Trigon provided a range of engineering, design, construction inspection, construction management, environmental support, and permitting services for the program. Trigon provided construction management and resident inspection services for projects to rehabilitate vintage turbines and generators in the plant. Relative to engineering, design, environmental services and permitting, and project management, Trigon also led the following two specific projects:

Power Distribution System Design-Build: $25M project to replace critical power distribution feeders throughout the City that serve major water, wastewater and drainage facilities. Due to the critical nature of this work, the accelerated timeline in which it must be performed, and the complex coordination necessary between this and many other ongoing projects, a Design-Build delivery method was selected. Includes the installation of 100,000 linear feet of new electric conductors and 40,000 linear feet of new duct bank. Due to excellent performance through the RFP preparation and bidding process, Trigon’s Project Manager was specifically requested by the client to serve as their Owner’s Rep during construction. D-B efforts began in Summer of 2015.

Emergency Fuel Storage System: Trigon performed all engineering and design for this approximately $8M project that includes two (2) 522,000 gallon diesel storage tanks; containment area; and delivery system comprised of one (1) 15,000-gallon day tank, piping, and valves. The project also includes the following ancillary equipment: two (2) fuel polishing units, one (1) oil-water separator, and a fire suppression system with AFFF bladder tank, potable water booster pump, and fire detection system. Additional components are below-grade piping, electrical and controls from the two (2) 522,000 gallon tanks to the day tank, and jack-and-bored sections of piping, electrical and controls from the day tank to the existing fuel-forwarding pumps in the basement of the boiler house. Trigon also performed environmental review.