Water and Wastewater Treatment
Buildings and Structures
Novato Sanitary District, Seismic Evaluations
TJCAA performed structural evaluations of digesters (concrete structures) at the District’s WWTP and deep bed filters and secondary clarifiers for the District’s tertiary treatment facility. TJCAA’s evaluations identified seismic vulnerability, verified code compliance, and determined locations for new equipment in existing structures. TJCAA evaluated options for placement of filtration, disinfection with UV or chlorine, and residual disinfection systems at the recycled water facility. Emphasis was put on finding options for reuse of existing structures.
The Brentwood WWTP Expansion Project, with a construction value of over $48 million, included replacement of an existing plant while the existing plant remained operational until completion of the new facilities. TJCAA provided structural design, predesign, design, and construction services for the entire upgrade facility as part of the G.S. Dodson & Associates, Inc. team.
City of Belmont-Recreation Facility
Structural design of a two story concrete block recreation facility and two concession/restroom buildings for new softball fields.
City of Glendale- Groundwater Remediation Project
Structural design of facilities associated with this ground water remediation project. Elements included seismic anchorage, operations facilities, chemical storage, groundwater well vaults and a 240 foot clear span pipe crossing over an existing water channel in Glendale, CA. The project required mat foundations to accommodate potential settlement from the existing unconsolidated soils.
Instrumentation and Control
The PLC upgrade project for a 21-mgd water treatment plant modernized an obsolete PLC system. TJCAA performed field investigations to update the as-built wiring diagrams, system design narratives, and coordination spreadsheet and programmed the new system to use the client’s existing control logic. In coordination with ACWD staff, TJCAA performed I/O testing, SCADA testing, and functional testing that simulated process inputs before the equipment was installed. TJCAA’s work on this project also included equipment commissioning, including operational readiness testing and functional acceptance testing.
The project addressed operational issues at a lift station including design improvements for motors and drives, updating control systems, and electrical servicing. TJCAA’s design team developed sequence of construction, phased service replacement, drive replacement, and infrastructure improvements to ensure continuous pump availability during construction. Additionally, the project included upgrades to the facility’s SCADA system RTU controls, including new hot standby redundant PLCs and backup PLC controls to eliminate pump station vulnerability to single points of failure.
United Water of Idaho, Columbia Water Treatment Plant: Design/Build of ultra-filtration membrane treatment process. Project required development of electrical and I&C documents at a level sufficient for construction permitting and to develop a guaranteed maximum price (Design/CM at Risk).
City of Santa Cruz, Graham Hill Water Treatment Plant Control System Upgrade: System upgrade project including vendor selection, system design, panel fabrication, coordination of subcontractors, installation, startup, testing, training, and follow-up/warranty tasks. The resulting SCADA system includes hot standby, redundant PLCs, updated plant control strategies, human/ machine interface software, RAID Category central workstations, and 30 remote radio telemetry units.
City of Folsom, Water Treatment Plant Control System Upgrade Design/Build: The control system architecture was designed to accommodate a doubling of plant capacity without modifications to the control system approach. The suitability of the approach was confirmed during subsequent plant expansion. Design/build approach included design of control system architecture and interface to remote telemetry, fabrication/installation of PLC back panels, testing and startup.
Seattle Public Utilities, Tolt Water Treatment Plant: Design/build grassroots 120 MGD treatment plant that included ozonation, flocculation, filtration, chemical feed, solids handling, and on site clear well storage. For the instrumentation and control system, a distributed control approach was used