- PC Construction
- Hopewell, Virginia
- Our Role
- Civil, Structural, Facilities, Environmental, Instrumentation.
- 36 mgd plant
- Construction Cost
- $24.6 million
- 2 years 8 months
- Potable system capacity increased from 12 to 18 mgd total
- Improved water flows between industrial and domestic pretreatment systems
- Plant able to go offline twice as long without a service interruption
- Design-build delivery method saved $500,000 in construction costs.
At the confluence of the Appomattox and James rivers in Hopewell, Virginia, lies the Hopewell Water Treatment Plant, a century-old facility owned by Virginia American Water, a subsidiary of the largest investor-owned water/wastewater utility in the U.S. From this plant, more than 9,300 domestic and industrial customers were being served by obsolete systems and infrastructure, some of which dated back to the early 1900s. With an aging facility and increasing customer demand, Virginia American Water was facing a number of issues, including industrial wood tub filters that were at the end of their useful life, a potable plant operating at 12 mgd firm capacity during peak months, limited space for staff and maintenance facilities, and outdated and inefficient laboratory facilities.
Hailed as the first design-build project of its kind in Virginia, the facility underwent an extensive series of upgrades designed to increase its filter capacity, storage, pumping, and overall capacity with a project scope that involved virtually every aspect of the plant. The result: an efficient, state-of-the-art plant celebrated by the project stakeholders and the Hopewell community.
As lead designer, Gannett Fleming provided design-build services for this dual-natured plant, which treats water through two separate processes for domestic consumption and industrial use. Our firm addressed challenges with both the domestic and industrial systems.
For the domestic system, we increased the potable system capacity to 18 mgd total; upgraded the sedimentation basins and tube settlers; added new domestic filters and granular activated carbon (GAC) vessels; added a 2.5 mgal clearwell; added and replaced high-service pumps; and designed chemical feed improvements, administration and maintenance building additions, and control and instrumentation improvements. For the industrial system, Gannett Fleming delivered wastewater improvement design solutions, and provided for the demolition of old industrial wood tub filters and their replacement with high-rate multi-media filters. Our firm additionally completed a number of project studies at Hopewell, including wetlands investigations, hazardous materials investigations, hydraulic analysis, a surge study, geotechnical analysis, electrical study, and structural inspections. Identifying value-added opportunities throughout the project, Gannett Fleming created savings that were ultimately made available for the construction of a new standby generator suitable for maintaining plant operations during a power failure.
- Two additional dual-media domestic filters, rated at 6 gpm/sf
- Four additional domestic GAC pressure contactor vessels
- Addition of a 2.5-mgal domestic clearwell
- Domestic high-service pumping improvements, including an additional 5-mgd pump and replacement of an existing 6-mgd pump
- Tube settler units in the domestic sedimentation basin
- Complete replacement of the existing industrial wood tub filters with new high-rate filters
- Process wastewater handling system improvements, including an equalization basin, new wastewater pumps, and innovative solutions, including the recycling and direct reuse of the domestic filter rinse in the industrial system
- Hydraulic modifications to allow gravity settled water transfer between process trains.
- Recycled 100-year-old Redwood and Cypress from the original tub filters
- Reused existing asphalt
- Eliminated more than one million gallons of process wastewater per day, which resulted in savings of energy, chemicals, equipment, and operating costs.