Santa Rosa Water Reclamation Facility Rehabilitation

This $28.5 million, Design-Bid-Build project, was completed in 2021 and performed the rehabilitation of the Santa Rosa Regional Resources Authority Water Reclamation Facility. The Project involved the complete upgrade and retrofit of 5 existing Sequencing Batch Reactors to meet current and future demands for wastewater treatment, and to ensure the operational viability.  As this was an active facility, only one reactor could be taken offline at a time. This was complicated further as the new reactors are controlled by a new PLC with different control logic. This project required that all project stakeholders collaborate very closely for it to be a success. At the start of the project GSE immediately began working with the operations and maintenance staff to understand their treatment requirements and constraints so that a plan and sequence could be developed that would minimize impacts to the facility. This collaboration continued throughout the project as operations were intimately involved with each phase of work. GSE met with operations on a weekly basis to discuss the upcoming work and coordinated several workshops which ensured a successful project.

As previously mentioned work consisted of the complete rehabilitation of five Sequencing Batch Reactors (SBR), including demolition of the existing mechanical process system, concrete repair and application of protective coatings, installation of new process equipment, installation of new blowers and air piping, and the installation and integration of new electrical and controls. As this is an active facility, each SBR had to be rehabilitated sequentially to allow the facility to maintain their treatment requirements. The project also involved the construction of a new Solids Handling Facility that included a sludge holding tank with a Deep Soil Mixing column foundation, course air diffusers, rotary screw positive displacements blowers, rotary drum thickeners, dewatering presses, sludge pumps, polymer storage and feed facilities, and a truck loading area .Advanced Geo Solutions, brought in an onsite batch plant and about 500 piles were drilled by the subcontractor, to create the soil mixing foundation. The  metal building for the Solids Handling Foundation was about $2M in steel/erection costs. This required heavy coordination with equipment placement, concrete anchor placement, piping, monorail vendor, etc. Additional work included the installation of new clarifier mechanisms and Sludge Pump Station for Tertiary Clarifiers Nos. 1 and 2, concrete repairs and the application of new coatings in the influent channels within the headworks Building, and Grit Chamber, a full influent flow bypass to allow for pipe modifications and the installation of valves on the main influent pump station discharge line. GSE was able to deliver and complete this project on time.