Submission by Caroline Meiss
Edited by Mandy Crispin
The largest capital improvement project for McCormick Commission of Public Works CPW), the new 3.7MGD water treatment plant, was an impressive feat for Harper General Contractors. The project involved a phased construction plan to allow for maintenance of plant operations, extensive coordination so that the conversion of the tank did not disrupt the flow of clean drinking water, and significant value engineering that gave the owner options without sacrificing value.
The existing plant was built in 1926 with upgrades/expansion over the following century. The plant needed to be decommissioned and replaced as they were running out of footprint at the existing site and the age of the plant caused operations to go from maintenance to complete replacement of many of components/processes. The CPW owns a tight piece of property across the street from the existing plant, which is where the new plant was constructed. Due to the footprint of the new plant, construction planning efforts were extensive and had to be updated throughout construction for each phase of the job.
One of the team’s main project goals was to work to develop a functional and aesthetically pleasing new facility to serve the growing community. The operations building was designed as a split-level structure with office, training room, and lab on one level, and stairs leading up to a filter control room and down to the pipe gallery.
The design included several windows in the pipe gallery to provide natural light and a retaining wall that enables exterior double door access to the lower level. From the control room upstairs, the operator can survey the entire complex: the parking area, high service pump station, and sedimentation basins just outside, as well as the flocculation, bulk chemical, and rapid mix structures at the far end of the complex. The elevated sedimentation basins can be accessed through the control room or by exterior stairs, and walkways provide access to either of two treatment trains. A disinfection generation room flanks the sedimentation basins, continuing the split face block and metal roof style, while an existing metal building on site was preserved, merging well with the utilitarian feel of the treatment campus.
In addition to serving the community, the project involved a phased construction plan to allow for maintenance of plant operations during the construction. At the original WTP, an existing water tank used for storing drinking water onsite before sending for distribution was converted to a backwash waste holding tank while the existing plant was in service.
This process involved extensive coordination so that the conversion of the tank did not disrupt the flow of clean drinking water. The team was able to deliver a new 600,000 gallon clearwell tank as part of the new WTP early to serve as an area to hold the drinking water while bringing the backwash waste holding tank online. Extra goal efforts were made by the construction team to minimize impacts from construction materials and equipment deliveries. Communication with the owner and surrounding neighbors was constant to ensure their days were minimally impacted from construction.
Harper achieved the goal of providing a safe project site with McCormick WTP’s involvement with OSHA’s Voluntary Protection Program which recognizes companies that have implemented a comprehensive safety and health management system. During the partnership, the job site was subject to quarterly collaborative site visits and OSHA audits.
A total of 121 inspections were conducted and a total of 211 hazards were identified. All the hazards identified were corrected or effectively eliminated.
The field team performed several different types of self-inspections and audits on the jobsite. Walk-around inspections were conducted by the OSHA Partnership Safety Committee every quarter. Senior management conducted safety inspections quarterly and audited “Presence of Safety Reports.” The project team also performed discussions about safety topics throughout the day as they observed someone approaching the line of performing work unsafely.
As demonstrated by the lack of recordable incidents on this job, the extra time taken by the team to review safety certainly paid off. The job site conducted OSHA 10-hour and OSHA-30 training on an as needed basis in both English and Spanish. Several of the larger subcontractors had previously provided their workers with 10-hour training. The safety record for this project allowed the team to maintain a clean record for this project and make sure they kept a clean, safe jobsite for both the neighboring communities and the project team.
The main project challenge for the $14MM Greenfield WTP, hard-bid project was significantly over budget, leaving CPW with limited options on how to move forward. Within two weeks of being low bidder, Harper compiled and provided CPW and Turnipseed with a preliminary value engineering (VE) option list that included approximately $1.3MM in project savings. Each VE item gave the owner options without sacrificing value.
As the VE discussions developed, and while working closely with Turnipseed, Harper priced treatment methodologies not included in the original bid documents. The options compared mechanical flocculators to the original baffle wall flocculation. Harper and Turnipseed also examined plate settlers and tube settlers versus the original baffle wall settling basin and sourced alternate filtration design options to provide cost savings while maintaining treatment function.
The final VE collaboration among McCormick, Turnipseed, and Harper has resulted in nearly $2MM proposed project savings, allowing negotiations to continue moving forward to achieve the owner’s budget and allowed them to choose the options that provided the CPW with the most value.
This VE exercise was unique for two reasons. First, most design-bid-build projects do not receive VE. The low bid price is either accepted or the project is rebid if it exceeds the budget. It is rare for the low bidder to receive the opportunity to provide VE input post bid. Second, McCormick CPW received USDA funding for this project. Grants and loans carry specific requirements, including schedule and procurement rules. Typically, this type of funding does not allow for post-bid VE exercises. The project team collaborated with USDA to move forward with VE and, ultimately, the project.
Neither McCormick CPW or Turnipseed had experienced an alternative delivery project. Through navigating the collaborative VE process with the client and design partner, this project became more of a Construction Manager At-Risk delivery method. CPW and Turnipseed both grew to a level of appreciation for this collaborative delivery method. The result of this successful collaboration was that the Town of McCormick advertised its first ever CMAR project, for an upgrade at its wastewater plant, and Harper was the selected CMAR for this project.
Another challenge faced was the decision to demolish the old plant after commissioning the new plant was one that the CPW had been considering from the very beginning. Due to funding constraints, CPW had to monitor funds available and at about 85% complete, they decided to move forward with demolition based on the project progress and available funds. By helping control and manage the project budget/funds and make decisions at appropriate times, CPW was able to regain the piece of property where the existing plant was sitting on as a greenspace for the local community.
Project Location: McCormick, South Carolina
Project Size: 3.7 MGD
Facility Size: N/A
Budget Cost: $15,098,885
Project Owner/PM: Cheryl Daniels
Project Designer: David Tyre
Project Contractor: Harper General Contractors
Project Manufacturers: Xylem, Leopold, MRI, Denora, Simflo, CRU Pumps