Project Status: Underway - Construction
Estimated Cost: $280 million
Start Date: June 2017
Estimated End Date: Dec 2021
Magisterial District: Project Located Outside of Henrico
Cobbs Creek Reservoir is the County’s $280 million project to secure its drinking water needs for perhaps the next five decades. The Cobbs Creek Reservoir is a 14.8 billion-gallon regional water supply impoundment located in Cumberland County, Virginia that will augment the flow of the James River as needed. Water will be pumped out of the reservoir and into the James River in the drier months, and it will be pulled from the James River into the reservoir in the wetter months. The reservoir will help during drought or near drought conditions with providing extra water to the flow of the James River.
In exchange for the construction of the Cobbs Creek Reservoir, Virginia Department of Environmental Quality has approved an increase of the amount of raw water that Henrico County can take from the river each day to supply drinking water. Previously, Henrico County could withdraw 45 million gallons per day on average. Under the new approval, Henrico County can withdraw up to 75 million gallons per day on average. These higher limits will allow Henrico to serve water customers as the county continues to grow for perhaps the next 50 years depending on the County’s rate of growth.
The facility creates an additional 17 million gallons per day approved by the Virginia Department of Environmental Quality available to Henrico and its regional partners.
Henrico has completed Phase I of the project, which was the acquisition of all the properties. Staff from both Real Property and Public Utilities worked with 22 property owners to coordinate the purchase of the required property.
Phase II of the project, where Colonial Pipeline Company and Dominion Energy relocated their existing utilities from the reservoir pool to outside the reservoir footprint, has also been completed. During Phase II, DPU’s contractors also completed the construction of a communications tower and road system.
Phase III of the project began in October 2016 with the bidding process for the construction of the three earthen dams, the water intake structure in the James River, a pumping station, and other facilities which will support this massive operation.
On March 2, 2017, sealed bids for the project were opened and read aloud by the County’s Purchasing Division. After evaluating these and determining the lowest responsive and responsible bidder, the Board of Supervisors voted unanimously and awarded a contract for the construction of the reservoir to MEB Haymes Joint Venture LLC for $137.4 million on April 25, 2017. This was lower than the design engineer’s estimate, and the seven bids received ranged from $137.4 million to $209.4 million. MEB Haymes Joint Venture LLC is comprised of MEB General Contractors of Chesapeake and Haymes Brothers, Inc. of Chatham.
Construction on Cobbs Creek Reservoir began in June of 2017. Since mobilizing the contractor has cleared areas of land to construct the access road to the pump station, the pump station site, and the soil borrow areas for the soils used to construct the dams (main, saddle and perimeter access road dams). In addition, excavation of the pump station and installation of the coffer dam is complete. The contractor is currently working on the concrete work and piping for Intake and Valve Vault Structures #1 and 2 behind the cofferdam in the James River. They have completed the concrete work at the pump station to the bottom of the lower floor level and tested the wet wells. The Cobbs Creek diversion has been rerouted into the 84-inch inlet/outlet pipe to the dam and the inlet/outlet tower at the main dam. The contractor has remobilized the crane to begin the final construction phase of the Inlet/Outlet Tower. The Quarry has been completed. Work on the Perimeter Access Road Dam and Saddle Dam area about 95% complete. The contractor has completed the grout curtain and slurry wall in the main dam and has completed with the Energy Dissipater. Upcoming, the contractor will complete placing the 72-inch piping from the drain valve vault (at the dam site) to the Pump Station, continue working on the intake structure piping and value vaults at the river site, adding core and shell material lifts along the dam footprint, building the Pump Station and Inlet/Outlet Tower and begin construction of the Operations Building.
In total, there will be over 3.5 million cubic yards of soil excavated across the 1,117-acre site and used to build the three earthen dams. The Perimeter Access Road Dam will be approximately 19 feet tall and the Saddle Dam will be about 25 feet tall and 1,200 feet long. The larger main dam will stretch 3,850 feet in length along the north end of the reservoir and be 160 feet tall. Additionally, there will be an intake structure with piping, a pump station, and an operations building all constructed by the James River to aid in the filling and draining of the reservoir.
Construction of this project is anticipated to be completed in approximately 4 years, and the reservoir is expected to be fully operational in 2022.
Progress to Date
Utility Clearing – Began in July 2015 and completed in February 2016
Utility Relocation – Began in March 2016 and completed in December 2016
Dam & Facilities Construction – Began in June 2017 with expected completion in December 2021