James J. Corbalis Water Treatment Plant — Value Engineering
Merrifield, VA
The Fairfax County Water Authority (FCWA) sought to create one unified water treatment facility. To achieve this goal, some existing facilities constructed in the James J. Corbalis Water Treatment Plant Stage I phase were modified to mirror the Stage II and future Stage III facilities.
The authority wanted to achieve a 50 million gallons-per-day (MGD) increase in capacity to avoid the addition of another 25 MGD of capacity within a relatively short period of time after project completion.
The objective of a value engineering (VE) study conducted by ARCADIS was to:
- Identify areas in the design that offered opportunities for value enhancement
- Generate alternatives to provide desired enhancements
Two five-day VE workshops were facilitated by an ARCADIS certified value specialist with a team of water treatment professionals. The workshops were performed at the 30% and 60% design completion stage and utilized a six-phase VE Job Plan.
The first VE study explored process options and optimizations for major project elements and resulted in the identification of $1.5 million in cost savings. In addition, $500,000 in quality enhancements were added to the project.
The second VE study focused on design details and the constructability of the project and produced several ideas for saving costs on the site work, structures and electrical upgrades to the raw water pumping station. A schedule analysis demonstrated how the construction period could be reduced from 42 months to 34 months, saving contractor general conditions and administrative and site oversight costs.
In addition, a means for preserving the main plant entrance (impacted by pipeline installations) were also presented to FCWA, as well as ideas to improve the functioning of the completed facility.
The team generated more than 100 specific constructability comments on the specifications and drawings, with the goal of avoiding conflicts and potential changes during the bidding and construction.