The town of Gilbert, Ariz., and the city of Chandler, Ariz., needed an expanded treatment facility to be online to double its capacity by Feb. 23, 2018. This was meant to protect public health by giving both municipalities additional production capacity to meet rapidly growing municipal and industrial demands.
The team split the construction into two guaranteed maximum price (GMP) proposals and collaboratively identified equipment to procure in the first GMP to facilitate the project schedule.
The team had many goals, but one stood above the rest.
“The most important goal for the Santan Vista [Water Treatment Plant] expansion was the integration of operations into sound engineering design to facilitate a smooth construction effort that met the goals of on-time, on-budget, and operations-forward project delivery,” said Mike Caruso, project manager for Black & Veatch Corp.
The project expanded upon the use of state-of-the-art, small-footprint, high-rate ballasted flocculation technology and combined the ability to feed ozone for pre-oxidation of organics in a raw water ozone pipeline contractor as well as a post-flocculation ozone contractor to exceed all water quality goals established by the town and city and required by law.
The town and city requested multiple equipment suppliers be allowed to compete. The team followed a thorough procedure to allow consideration of alternative equipment suppliers instead of pursuing sole-source procurement.
“The biggest challenge was maintaining plant operations and preventing non-planned shutdowns,” Caruso said. “The planning for this started early in design with multiple meetings with the entire team to discuss not only what was being expanded, but how it would be expanded. We were able to identify early all of the tie-in locations and how each could be accomplished.”
The town and city takes safety seriously and made certain it would be a focus for the project. Every meeting, from the start of design through finish of construction, began with safety-related tips. During the design process, Black & Veatch utilized building information modeling (BIM) 3D modeling and Sundt’s 3D laser scanning of the existing facility to virtually create the existing and new spaces to better interact with the town and city’s engineering, operations and maintenance personnel. The tool helped users discuss safer means of access to multiple existing and expanded portions of the facility both during and after the construction. The models and scans assisted in helping the team identify potential risks and avoid unintended plant shutdowns.
“The BIM 3D models were extremely useful during the design and construction process. We merged the laser scan data with the BIM models to help the entire team virtually walk through project expansion in the conference room before ground was broken,” Caruso said. “It also allowed us to speed up the design process and produce the necessary technical memoranda and drawings in an understandable format, which sped up design review to meet the aggressive 12-month design and 18-month construction schedule.”
The need to maintain an open collaboration and communication between all team members was heightened due to the need to not only maintain the town’s existing facility operations and distribution system supply to multiple pressure zones, but also ensure potable water needs are met for the city of Chandler.
At the end of the day, the existing co-owned Gilbert-Chandler Santan Vista Water Treatment Plant was successfully expanded from 16,666 gal per minute (gpm) to 33,332 gpm while saving both municipalities approximately $15 million, or nearly 20% in program costs. At substantial completion, the relatively conservative owner’s contingency still had more than 50% of funds available.
The Gilbert project manager noted that as items were identified, all parties—Gilbert, Chandler, Black & Veatch (engineer), Sundt Construction (contractor), and their subconsultants and subcontractors—continued to work together as a team and maintained positive working relationships to the very end. In addition, she noted a number of people working on the project with multiple entities were given additional responsibilities and ultimately were promoted, which can be attributed to the project’s success. This project is one of which everyone involved can be proud.
“I’m extremely pleased with the result. The facility was master-planned for this expansion and, now that it is completed, everything ‘fits’ as if it had always been there,” Caruso said. “The relationships the team established throughout the process will definitely continue well into the future.