A year before construction began, the city proactively made the choice to gain public support for the project by keeping the community updated on all construction activities. As part of the project’s community outreach, McCarthy participated in regular meetings with Neighborhood Focus Group members to provide project status updates. Additionally, about 2,700 residents from nearby neighborhoods were invited to a meeting to express their thoughts regarding the city’s plan to expand the reclamation facility. Another meeting was held just before the start of construction to share the construction timeline with the public.
In response to the public’s concerns expressed at each of the community meetings, considerable care was taken to minimize plant noise, such as housing loud equipment in acoustically treated buildings, placing structures below grade and using sound absorption panels inside key structures.
Additionally, odor control measures were applied at several treatment process areas within the plant, and the project’s aesthetics were improved. Site beautification enhancements entailed new landscaping in public-facing areas, screening rooftop equipment and covering the clarifiers, basins, chemical facilities and pump stations with metal canopies.
To ensure continual plant operations during construction, McCarthy and Wilson Engineers worked together during the preconstruction phase to develop a thorough coordination plan addressing the maintenance of plant operations (MOPO) throughout the expansion. This process included the creation of a framework to each MOPO activity as a part of the project’s formal planning meetings. Wherever possible, the team developed strategies to sequence construction activities, eliminating interaction between the operating plant and the construction process. In other situations, the building team worked to limit the impact of MOPO activities by making connections during non-operating hours or connecting to only one train of a unit process at a time.
As a solution to the unanticipated increased flows into the facility during early stages of construction, the team met frequently and identified facilities that required completion for rerating. After pinpointing several facilities, the building team expedited construction and procured the equipment needed for operation. Due to this effort, the city’s goal of rerating the facility to 12 MGD one year before the project’s substantial completion was successfully accomplished.
Another inventive solution involved phasing construction of the liquids treatment train approximately six months prior to completion of the solids train. This effort helped supplement the city’s groundwater supplies by streamlining the flow of treated effluent to a recently constructed recharge basin while continuing to ensure that only Class A+ quality water was discharged during construction and plant startup phases.
Due to the project’s location adjacent to the Chandler Airport, great care was taken by the project team to protect the public and mitigate any impact on airport operations. Through constant communication with the airport, the team provided airport officials with the location of the taller cranes and, in some instances, crane heights were modified to alleviate interference with aircraft approaches and takeoffs. Flagging and lights were also used to mark the crane locations, and cranes were lowered before dusk.
Migrating ducks attracted to the large water-bearing structures at the plant posed another potential safety hazard to air traffic upon take-off and landing at the airport. As a preventative measure, metal canopies were designed and constructed to cover all exposed water holding tanks.
Various sustainable construction solutions were also implemented to reduce impact to the environment during construction. All concrete and asphalt removed during the expansion was stored on site until it could be efficiently hauled to the local Chandler concrete recycler, where it was crushed, and then reused to pave the roads on site. Special procedures were also put in place to protect air quality, such as gravel, water application systems, and track-out control devices to curb pollution.