BROOMFIELD - MWH Constructors Inc. in Broomfield received a $57 million contract to provide preconstruction and construction manager-at-risk services to upgrade and expand the city of Fremont, Ohio's water-pollution control center.

The existing wastewater collection system was built in 1949 and is a combined sewer overflow system. The project will expand capacity from 6 million to 24 million gallons per day.

Construction is scheduled to begin this spring with a completion date of December 2015.

MWH Constructors has teamed with Mosser Construction, a Fremont-based general contractor, to assist with preconstruction and construction activity.

MWH Constructors is the construction-services arm of Broomfield-based MWH Global Inc., an international consulting, technical engineering and construction services firm in the wet infrastructure sector. It is a private, employee-owned firm that has 7,500 employees in 35 countries spanning six continents.