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Livermore
Water Reclamation Plant – Plant
Expansion
WBA led the design of a 2.25 mgd, Phase 5 expansion of the Livermore
Water Reclamation Plant. This project involved expansion or
upgrading of the major treatment units and the associated process
and utility piping and pumping system. In addition, the project
included the planning and design of a completely new digested
sludge system with high-rate facultative sludge lagoons and
two stage paved drying beds. Finally, the project included
the design of a new administration and control building, a
new maintenance building, retrofit of the original operations
building to serve as a laboratory, and a new entrance road
surrounded by a park-like area featuring ornamental and irrigation
uses of reclaimed water. Team architects assisted in gaining
acceptance of the project by the City design review commission.
City
Of Millbrae – Plant
Improvements
The City of Millbrae selected WBA to design several major improvements
to their wastewater treatment plant. The improvements consisted
of modernizing the headworks and influent pumping facilities,
rehabilitating the primary and secondary sedimentation units
and replacing the
sludge dewatering centrifuges. The headworks and influent pumping
facilities modifications consisted of replacing the single, variable
speed pump, two fixed speed horizontal centrifugal pumps and
outdated comminutors and screening devices with three vertical
pumps and
three hydraulically operated comminutors. The primary sedimentation
units modifications included new roofs, new chain drives and
temporary structural supports to hold the tanks in place while
the roofs
were being replaced. WBA designed the replacement of the rotating
screens in the secondary sedimentation tanks with fiberglass
baffles. Modifications to the tilting weir skimmers in the
cells of the
chlorine contact tank enabled the rotating skimmer to be eliminated,
thereby increasing the hydraulic capacity of the entire plant
from 7 mgd to 10 mgd. The sludge dewatering centrifuges were
replaced
with a belt filter press, and the building housing the centrifuges
was modified to accommodate the new equipment as well as to shield
the operators from the weather and freeway noise. Heavy rainstorms
that occurred during the 1992-93 rainy season were a major test
of the improvements. The success of the improvements was proven
by the fact that, for the first time, the City did not experience
any NPDES violations during a heavy rainstorm.
FSSD – 2002
Maintenance Project
WBA designed numerous wastewater treatment plant and pump station
modifications for the Fairfield Suisun Sewer District as
part of the 2002 Maintenance Project. Modifications included installing
a second pH meter with associated control improvements
to
control
influent pH, analyzing and upgrading the variable speed RAS
pumping system, replacing existing raw sewage pumps and installing
new
VFDs, analyzing and modifying the sludge holding tank mixing
system, locating and repairing leaks in a buried aeration
header, and installation
of a security system at the WWTP site.
SKF – Sludge
Dewatering Facility
WBA completed a sludge dewatering study for SKF that recommended
the installation of a centrifuge. Based on this study, WBA prepared
the procurement documents for the District to pre-purchase a
centrifuge unit with a capacity to dewater 200 gpm of feed sludge
at 2% solids concentration. The selection and award of the purchase
order was based on the evaluated costs which accounted for the
equipment cost, the projected system performance, and the 10
year projected O & M costs. SKF purchased and took delivery
of the centrifuge based on this procurement process.
WBA designed the facilities needed to complete the sludge dewatering
system using the prepurchased centrifuge. The facilities include
a new centrifuge building, a sludge feed pump, a polymer preparation
and feed system, a sludge cake pump system and associated civil,
mechanical, control and electrical systems. The design of the system
includes allowance for installation of a second centrifuge unit
in the future.
The above projects are representative of our experience in this area.
If you
would like additional information on these, or other projects that
we
have completed, please contact us.
For detailed descriptions
of representative projects in our other areas of expertise,
click below on the category you are interested in:
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