The project consisted of upgrades and additions to the existing water pollution control plant. Work included a new Influent Pump Station, additional chemical treatment facilities, three new secondary clarifiers, upgrades to the SCADA system, and the installation of a digester gas scrubbing system. The project included 17,000 sq. ft. of sheet piling, 47,000 cubic yards of excavation, 41,000 cubic yards of backfill, 8,000 cubic yards of cast-in-place concrete, installation of over 15,000 lineal feet of piping, installation of process equipment and electrical and control systems.
Substantial upgrades and additions were constructed by Monterey Mechanical to increase treatment capacity to 20 MGD. The scope of work included construction of:
- New influent pump station
- New bar screen/grit facilities
- Three new 120-ft. diameter primary clarifiers
- New disinfection channel
- New chemical treatment systems
- New effluent pump station
Scope of work for existing facilities included:
- Modifications to digesters
- Modifications to aeration basis
- Replacement of DCS to integrate new facilities
Challenges | Solutions
The biggest challenge for the Oro Loma Water Pollution Control Plant was preventing disruption to operations and loss of process capacity during construction, as well as avoiding unscheduled interruptions to the plant’s treatment capacity during testing, commissioning, and startup.
To resolve this, Monterey Mechanical maintained continuous plant operations by sequencing demolition work at the Aeration Basin so that half the tanks were kept in service while work progressed in the other tanks.
We also shaved one year off the schedule by proposing and designing a bypass piping process that eliminated the need for pumping, which allowed work to progress on the Chlorine Contact Tanks. We added stop logs to the channels at the headworks, so work could continue behind them while the influent channel remained in service.