Challenge

The public water supply in Greene County, Ohio, comes from an underground aquifer. As the water is pumped from beneath the ground, it passes through limestone, which results in hard water that has a high concentration of minerals, particularly calcium and magnesium. The preexisting water treatment facilities would not remove any of the calcium and magnesium, therefore requiring residents to install expensive and difficult to maintain in-home water softening systems. To soften the water prior to distribution, Greene County (County) decided to upgrade its water treatment facilities to include reverse osmosis membrane nanofiltration to lower the water hardness to approximately 8 grains per gallon (gpg). In addition to the softening improvements, the County’s capacity for finished water was expanded to 12 million gallons per day (mgd) from the previous capacity of 10.5 mgd.

Approach

Greene County began the planning process for this project in 2018. During the planning process, it was determined that the progressive design-build delivery method would be used. It was the County’s intention to collaborate with a designer and a contractor to provide a high quality facility with a minimum 20-year service life while minimizing life cycle costs and implementing an effective safety program based on the industry’s best practices. The Shook/AECOM joint venture (JV) was awarded the project.

To meet the expedited schedule, the JV overcame supply chain issues caused by the COVID-19 pandemic by identifying historically long lead-time equipment and beginning the procurement process as soon as possible so that schedule impacts were minimized. The JV also used the individual firms’ experience and extensive project backlog to identify specific equipment that was being affected by pandemic issues. This allowed the JV to collaborate with the County to make sure equipment orders were approved and put into process in a quick manner. The JV also developed an enhanced scheduling concept to decrease general condition costs, compress the schedule, and allow the existing facilities to remain in service while the new facilities were constructed.

The JV worked to design and build a 25,000-square-foot building to house the six RO skids housing 1,638 individual membranes as well as expansion space for an additional two RO skids. The facility includes 60 pumps, 41 analyzers, and 39 flow meters that transport and track water quality characteristics to ensure the facility is working as intended. To ensure the water quality standards were met, a multifaceted commissioning and start-up plan was developed so that all the equipment was in working order prior to being officially turned on. The startup and training were coordinated with all members of the team including the JV and the owner and its representatives. Lastly, an acceptance testing plan was formulated and all water characteristics were confirmed to meet the water quality standards as stated in the planning and design documents.

In January 2025, softened water was officially delivered to Greene County’s customers. The project improved water quality for taste, clarity, and odor and provided cost savings based on improved heating efficiency and replacement costs for customers.

Results

This was Greene County’s first collaborative delivery project as well as the single largest investment in its history. The importance of delivering a successful project was felt across all team members. True collaboration was necessary to ensure that the tight schedule could continue to move forward without being held up waiting for a decision to be made. As many meetings as necessary were held and open communication lines were kept between the JV team, the plant operation staff, and the owner and its consultant teams. In addition to the open lines of communication between the owner and JV, it was of utmost importance for both members of the JV to maintain constant communication. Members from both JV companies were onsite daily and worked hand in hand to make sure all necessary submittals received approval in a timely manner and technical decisions could be made immediately. This also allowed the JV to direct their subcontractors without delay so their work could continue unimpeded.

As the quote from Alan Lakein goes, “Failing to plan is planning to fail.” This was 100% true for this project, and all the important planning done across all phases of the project provided the groundwork to deliver a successful project for the owner. However, no project goes entirely according to plan. During the initial commissioning of the plant, it was discovered that the existing filters were not performing to levels that the planning documents stated they would. Excess iron was breaking through the filters which was affecting the performance of the membranes. This required commissioning to be paused and a plan to be developed that would allow for the plant to remain online while the existing facilities were improved so that the necessary water quality could be met. The JV worked with the owner to establish the necessary capacity to meet the demands of the system. The demand was met by the new facilities while the capacity of the existing facilities was minimized to keep water quality at the necessary levels. This allowed the existing facilities to be rehabilitated so that full iron removal could be met. In an abbreviated schedule, the existing 12 filters were fully rehabilitated with new filter media over a period of six months, which allowed the new plant to come online and provide high-quality water to customers.

Other WCDA members involved: Arcadis (owner advisor); Core & Main (supplier of DIP, HDPE, PVC pipe); Victaulic (supplier of fittings, couplings, and fabricated steel pipe)

“As the assistant director, I have met with all levels of staff and I witnessed firsthand how every level of the Shook/AECOM team was included in project discussions and decisions. There is a reassuring consistency among team members regarding goals, priorities, and execution strategies. Most importantly, every team member has a “project first” mindset. For example, I watched collaboration between the Shook Construction superintendents and the AECOM engineers quickly yield solutions to complex problems—keeping the project on track and providing the County with a better project. I cannot imagine a more seamless integration of diverse staff from two businesses into a single cohesive entity.

“The County has benefited immensely from how AECOM and Shook successfully integrated their leadership, engineers, and construction professionals into a cohesive, integrated single team using the joint venture model. I would highly recommend their team for future projects.”
—Randy Gilbert, Assistant Director, Greene County Sanitary Engineering