Under a two-phase, Design/CM-at-Risk contract, MWH designed and built a new 6-mgd water filtration plant adjacent to the City's existing 6-mgd convention treatment facility. Built in 1915, the existing Steubenville Water Filtration Plant is a 6-mgd conventional treatment facility that treats raw water from the Ohio River. In addition to the new 6-mgd water filtration plant, other major facilities included:

• Low-lift reservoir pump station
• Administration/laboratory/chemical building
• Backwash pump station
• Electrical building and emergency generation
• State-of-the-art SCADA system

The age of the existing Steubenville WFP presented the MWH project team with several unique construction challenges, the nature of which can be characterized by the division of the existing underground clearwell into two separate tanks. With the City lacking sufficient storage capacity to allow MWH to completely shutdown and drain the existing clearwell during improvements, the project team constructed a temporary 26-foot steel wall to isolate the two sides of the tank. Once isolated, MWH drained one side of the clearwell and erected the permanent wall while the other side remained online.

Needing to construct the new facilities within the old plant's existing site, MWH recommended the new plant feature high-rate Superpulsator technology. Superpulsator technology combines flocculation and coagulation in a single tank, eliminating the need for separate flocculation basins, which equates to reduced capital construction costs and site footprint. The new single tank provides excellent performance over a wide range of raw-water quality conditions, including river water similar to that of the Ohio River. Also, no additional sludge collection and sludge removal facilities were required, and the process does not significantly rely on mechanical equipment. The plant's existing flocculation/settling tanks were converted to the residuals holding tank and the existing residuals tanks converted to the backwash tank. Through this efficient facility siting and reuse of existing City facilities, MWH helped the City save more value time and cost.

Services Provided

• Design
• CM-at-Risk construction delivery
• Long-lead equipment purchasing
• Value engineering
• Constructability reviews
• Permitting
• Start up and commissioning

Project Highlights

• More than 90,000 man hours worked without  a lost time accident
• MWH saved the City of Steubenville more than $2M through value engineering and constructability