Novato Wastewater Treatment Plant Expansion & Upgrades

Location: Novato, CA

Owner: Novato Sanitary District

Contract: $68 Million

Role: General Contractor

Delivery Method: Design-Bid-Build

Result and Benefit to Client

Even with an almost six-month delay to the planned early excavation work due to differing site conditions, the Novato WWTP Expansion & Upgrades was delivered on schedule due to successful problem solving and partnering.

Project Description

Monterey Mechanical was the general contractor for an upgrade to the City of Novato’s existing 47 MGD wastewater treatment plant. Scope of work included construction of an influent pump station, headworks, two primary clarifiers, four aeration basins, two secondary clarifiers, RAS/WAS pump station, UV disinfection, digester, solids handling facility, effluent pump station, and a SCADA system. Monterey Mechanical designed the temporary bypass system.

Monterey Mechanical’s scope of work included construction of:

  • Influent pump station
  • Headworks
  • 2 primary clarifiers
  • 4 aeration basins
  • 2 secondary clarifiers
  • RAS/WAS pump station
  • UV disinfection
  • Digester
  • Solids handling facility
  • Effluent pump station
  • SCADA system

Construction required:

  • 47 MGD wastewater treatment plant
  • 72k cubic yards of excavation
  • 56k cy of backfill
  • 15k cy of cast-in-place concrete
  • 14k L.F. of piping, process equipment, and electrical control systems

Challenges | Solutions

To preempt safety and/or construction issues that might delay or increase costs on the $68-million Novato WWTP project, Monterey Mechanical located their Project Manager, Safety Manager, and engineering staff on the project site.

Monterey Mechanical facilitated early approval of submittals that enabled work to begin soon after NTP; obtained early approval of process equipment and piping; and expedited equipment deliveries.

To assure that no subcontractor scope of work was inadvertently left out of proposals submitted, during the bidding phase, we conducted a thorough analysis of the subcontractors’ proposals to ensure required scopes of work had been included.

We avoided unscheduled interruptions to the plant’s treatment capacity during testing, commissioning, and startup by developing a startup, testing and commissioning plan that included forms to document testing and readiness for service of each piece of equipment. We started each system as it became available, and kept existing systems in service until the new system was commissioned and performance tested for 30 days. As a result, continuous operation of the existing plant was maintained during construction of the upgrades.

Monterey Mechanical employed a cooperative partnering relationship with all stakeholders early in the project with constant communication to foster cooperative relationships.

Awards and Commendations

Beverly James
Manager-Engineer
Novato Sanitary District


“Monterey Mechanical built a great treatment plant and worked hard to prepare the treatment plant to look its best.”