Challenge
The coastal city of Boynton Beach expects to grow to upwards of 140,000 customers by 2035. With much of that growth occurring along the waterfront, coastal aquifers are unable to provide the needed water supply without risking saltwater intrusion. As a result, innovative water system upgrades were required to help the city continue to thrive. With significant water supplies located on the western side of the city, Boynton Beach had the water it needed, but it needed to move that water from inland to the waterfront, treat it, and combine it with the water from the coastal aquifers. Boynton Beach partnered with the design-build firm of CDM Constructors Inc., wholly owned subsidiary to CDM Smith Inc. as the prime contractor, engineer, and design-builder, along with its integral subcontractor Carollo Design-Build Group, a general partnership developed between Carollo Engineers and PCL Construction to deliver progressive design-build projects. The design-build team’s solution took the form of the Ion Exchange Resin Plant using a state-of-the-art MIEX® pretreatment system to help with odor removal and reduce chemical costs.
The City has long been a proponent of the progressive design-build delivery methodology and is utilizing it to execute several highly important projects in addition to this project. The City decided to move forward with design-build project delivery because staff and the elected representatives wanted to be involved in the design process to make decisions based on risk while allowing for cost control of the overall project. The contract was awarded through bid process with a two-step process whereby respondents were required to submit two envelopes. The first sealed envelope contained the qualifications requirements and the second envelope contained the price proposal.
Approach
The project included the design and construction of an Ion Exchange Resin Plant at the East WTP site for pretreatment of the water supply to the eastern service area from the western wellfield while upgrading the WTP to a capacity of 24 mgd. The utility’s water treatment capacity was constrained by three key attributes: restriction in a consumptive use permit for the east wellfields, growth in the eastern downtown areas, and a West WTP with raw water capacity but no space to expand. The creative solution to provide long-term potable water included using raw water from the west as a supply to an upgraded East WTP with magnetic ion exchange (MIEX) as a pretreatment technology to allow blending of different groundwater supplies into high quality and compliant potable water with a reduction in chemical costs. In addition, significant re-investment in plant upgrades, site layout efficiencies, and control systems allow the East WTP to provide the volume and water quality needed for generations.
Additionally, the innovative progressive design-build contract structure allowed for a substantial redefinition of the project concept. A new project concept was developed that could be constructed within the City’s budget while still meeting the City’s overall goals for the project. For example, the new Anionic Exchange Resin Treatment Facility, which was originally proposed to be constructed at the West WTP, was relocated to the East WTP. This change eliminated the need to construct a new 16 mgd capacity finished water transfer pump station at the West WTP, resulting in significant savings in capital costs and energy usage. As another example, the existing high service pump station at the East WTP was rehabilitated, which eliminated the need to construct a new 24 mgd capacity finished water transfer pump station and new 30 mgd capacity high-service pump station at the East WTP.
Using progressive design-build brought the project in significantly under its initial budget, which allowed for enhancements such as LED lighting for the city’s iconic water tower, a public art installation, and a medical clinic for Boynton Beach city employees. The project also earned the Institute of Sustainable Infrastructure’s Envision® Bronze award for its environmentally sensitive and sustainable elements.
Results
The MIEX portion of the project has been in operation since May 2017. The City is pleased with system performance and proud to state that this is the largest and most modern MIEX treatment plant constructed in the world. This project will support the potable water needs of a growing population and a thriving business community for the 30-year planning cycle and will ensure that the long-term potable water supply for the service area is protected and delivered effectively. The upgraded plant meets the community’s need to diversify water sources to reduce dependence on the surficial aquifer. Also included is a public art installation designed to create a connection between visitors to the facility and the facility itself. The new MIEX treatment technology, the full replacement of the filter valves and high service pumps, 3-million-gallon ground storage tank, and a new Profibus SCADA and HMI system for better control are the crowning achievements for this technically complex water treatment plant expansion that blends water from two treatment processes, improves the overall water quality, meets increasingly stringent regulatory requirements, and provides water for future redevelopment within the city.
The City’s goal was for this facility to be aesthetically pleasing to visitors and the community. The CDM Smith team exceeded the City’s expectations by incorporating the city logo of a sailfish on the ground storage tank, repainting all the key structures and areas, providing sealcoat of the existing pavement to match the new pavement, and replacing doors and storefronts—resulting in eye-pleasing views from all directions.
At the completion of the project, when the overall financial performance of the project was confirmed, CDM Smith identified over $2.5 million in cost savings from the impact of various design issues on the cost of construction. Nearly 20 local firms were engaged on this project.
This project is a 2018 DBIA National Project/Team Merit Award winner for water and wastewater and the 2018 DBIA Florida Region Best Overall Design-Build Project of the Year and Water/ Wastewater Florida Region Design-Build Project of the Year.
“The upgraded plant ensures that we will meet the growing demands of our water service area while reducing energy use and operating costs. This award-winning project contributes to our vision of making the City of Boynton Beach a leader in sustainability and resilience.
“This was a great project to do with progressive design-build. We pulled the best brains in, and as we were talking about the best way to build it, we were also coordinating costs. So we were able to make decisions very quickly based on real numbers and real costs, and still have complete control over what we built. And it was exciting! That’s why we got such a good product at the end of the project, because we were a team throughout.
“If you don’t have your basic infrastructure in place, you cannot grow. And this project guarantees our citizens and the customers a reliable source of water, so that in their lifespan, in their kids’ lifespan, they don’t have to worry. It’s important to us as utility executives to give that confidence to our customers.”
—Colin Groff, Assistant City Manager, City of Boynton Beach
