Geotechnical engineering, construction and general contracting firm Nicholson Construction has teamed up with sister company and ground improvement specialist Menard Group USA on the $38 million biodigester project at the City of Grand Rapids Water Resource Recovery Facility (WRFF).

The biodigester, part of the city’s efforts to rely 100% on renewable energy to power city buildings by 2025, converts food waste into energy. Construction of the biodigester includes three, large-diameter tanks, a process facility, a gallery and various other support structures.

Unsuitable ground conditions at the site were found to be insufficient to support the proposed structures.  In addition, up to 15 feet of fill was required across the site. The combination of unsuitable soil, fill and the proposed structural loads required ground improvement to meet the settlement criteria. 

Menard Group USA was contracted to provide a design-build ground improvement solution consisting of Controlled Modulus Columns (CMC) rigid inclusions.  Once CMCs are installed, a load transfer platform (LPT) will be placed. 

To remedy the voids found in the rock, Nicholson will drill and grout the voided rock on a pre-determined spacing for the planned area of the biodigester structures. 

“It’s always great to work with our sister companies on these large-scale projects,” said Dan Thome, Vice President, Central Region, Nicholson Construction. “Being part of the same larger company allows us to share resources and ideas to come up with the best value for our clients.”

The general contract for the biodigester project is the Christman Company.