Wastewater Treatment Plant Improvements
Project Overview
The Wastewater Treatment Plant (WWTP) on Mackinac Island had reached its capacity, making an expansion necessary to accommodate the increased demand. Although the Island’s winter population is around 400, it surges to 27,000 during the summer tourist season. This significant influx of visitors requires a facility capable of handling average daily flows of up to 1.54 million gallons.
F&V Construction (FVC) is executing the project using the innovative and cost-efficient “Progressive Design-Build” method. This approach allows FVC to handle the design, bidding, and construction phases for the new Mackinac Island WWTP. The project initially received funding from the Clean Water State Revolving Fund (CWSRF) through a mix of grants and low-interest loans, with additional support from a State of Michigan earmark. Key enhancements designed by our sister company Fleis & VandenBrink (F&V) included:
- A new headworks building featuring micro-screening, a grit removal system, and a septage receiving station
- Primary and final clarifiers
- Moving Bed Bioreactors (MBBRs)
- Rapid mix and flocculation tanks with mechanical mixing systems
- UV disinfection
- An effluent equalization basin
- Upgrades to the effluent pump station and forcemain
- A new process building to house blowers, pumps, the UV system, and electrical controls
- Updates to biosolids handling systems
- Improvements to the existing control building
- Plant automation for real-time operational control and SCADA integration
The construction faced logistical challenges, requiring all materials and equipment to be transported to the island by ferry or plane. Movement on the island is heavily regulated by City ordinances and state park rules, which cover over 80% of the land. To save time and costs, the City Council granted a special exemption to bulk vehicles for material transport. Additionally, the City prefers the winter construction season to minimize the impact on tourism. To manage the cold and snow typical of Michigan winters, ground thaw equipment, and insulated blankets were used to prevent materials and the ground from freezing.
