Lower Rouge Equalization Basin Expansion
Geotechnical and Construction Services
Western Townships Utilities Authority (WTUA) expansion project added
additional storage volume (doubling the available storage), and increased pumping capabilities. The storage volume for both dry weather and wet weather equalization is collected when wastewater volumes are high, and stored in the equalization basins until the volumes are lower, which allow the treatment plant to operate more efficiently.
This project included construction of an underground equalization basin with the dimensions of approximately 300 feet by 100 feet at the base and approximately 40 feet deep. The basin was constructed of cast-in-place concrete. The site was relatively constrained and excavation side slopes was a major factor during construction. Depressurization of the bedrock aquifer underlying the site was required to allow the deepest portions of the excavation.
Our professionals collaborated with the design team to assist WTA in
development of the construction plans regarding geotechnical aspects of the project including preparation of the project Geotechnical Report, development of several specification sections, and identification of key construction requirements.
Under Wade-Trim project management, we provided full-time resident
engineering field services during the various construction activities. An
experienced engineer made regular visits during the excavation and
dewatering phase to ensure smooth operation of work, observe for compliance with the submitted plan, and examine for unexpected conditions. We documented daily field activities, observed the placement of reinforcing steel and concrete, performed appropriate concrete testing, monitored soil backfill compaction and material usage, performed submittal review, and provided conflict resolution.