West Yost assisted the City of Woodland in expanding their
Wastewater Treatment Plant (WWTP) capacity from 7.8 mgd to 10.4
mgd, while also providing new tertiary treatment facilities
(oxidation, coagulation, and filtration and ultraviolet (UV)
disinfection of the effluent.) The project consists of an
expansion of the secondary process, new tertiary facilities, and
100-year flood protection for the main portion of the treatment
facility.
West Yost assisted the City of Galt in identifying and analyzing
alternatives for achieving compliance with NPDES permit
requirements. West Yost prepared a Permit Compliance Action Plan
that recommended alternatives. The City used this information to
proceed with near-term treatment facility improvements that will
also position the City to be responsive to future growth needs,
as well as additional changes in regulatory requirements. The
addition of filtration and ultraviolet (UV) disinfection was
identified as an important first step towards achieving
compliance with the City’s discharge permit. West Yost worked
with the City to pilot test filters and provided the preliminary
design of these new treatment processes.
West Yost has been providing wastewater treatment and
disposal system planning, regulatory compliance services and
engineering design for the City of Lodi White Slough Water
Pollution Control Facility (WPCF) since the late 1990’s. West
Yost completed design of the City’s $60 million improvement
project at the WPCF, incuding tertiary filtration and UV
disinfection facilities, expansion of the treatment capacity from
approximately 6.5 mgd to 8.5 mgd, and the addition of process
improvements to provide full ammonia conversion and partial
denitrification.
West Yost was recently selected to provide construction
management services for the City of Modesto’s $100 million Phase
2 Biological Nitrogen Removal/Tertiary Treatment Project. West
Yost has completed the constructability review of contract
documents. Phase 2 work will include construction of a new
advanced secondary treatment and tertiary treatment facilities
within the footprint of the existing secondary plant.
Mountain House’s Wastewater Treatment Plant was built in three
phases and completed by means of a design-build project
delivery method. West Yost provided full-time, onsite
construction management services for all three phases of the
project, which consisted of a new and subsequently
expanded WWTP, civil/site work, roadways, utilities, and
appurtenant facilities.
West Yost completed facility master planning and design to
address changing regulatory requirements for the City’s Easterly
Wastewater Treatment Plant. This project includes $130 million of
improvements required to meet new regulatory requirements and to
abandon the old North Plant and replace it with capacity in the
New South Plant.
West Yost provided planning and design for the City of Atwater’s
new Regional Wastewater Treatment Plant. The new plant was
required to increase average flow capacity to 6 mgd (expandable
to 12 mgd ultimate) and comply with new regulatory requirements
for advanced treatment. West Yost evaluated upgrades to existing
treatment plant facilities as well as alternatives involving
abandoning the existing plant and constructing new facilities on
a City owned site five miles from town.
West Yost is assisting the City of St. Helena in the development
of the best compliance solution for several outstanding
regulatory issues associated with their 0.5 mgd Wastewater
Treatment Facility (WWTF). One of the major drivers of the
proposed project is the need for expansion of the currently
available disposal operations, which include surface water
discharge to the Napa River from December through April, and land
application on property located adjacent to the treatment
facility. This project has capitalized on West Yost’s
understanding of and experience with wastewater permitting, and
includes ongoing interaction with the San Francisco Bay Regional
Water Quality Control Board.
West Yost completed the Facilities Plan for the Regional Water
Reclamation Facility (RWRF) in 2000 and recently updated the plan
to address newly adopted Total Daily Maximum Loads (TMDLs) for
temperature. The RWRF serves the urban areas of the Rogue Valley
including Medford, Central Point, Phoenix, Jacksonville, Eagle
Point, Talent and White City. The plan includes an assessment of
the existing facility capacity, flow and load projections, and
will incorporate a comprehensive energy management plan with
the goal of energy self-sufficiency.
The District operates a plant with four large lagoons followed by
disinfection prior to discharge to the Klamath River. It was
anticipated that the Total Maximum Daily Loads (TMDLs) to
the Klamath River would result in some of the most stringent
treatment requirements in the state. West Yost prepared the
facilities plan in response to preliminary TMDLs that were being
developed for the Klamath River. The initial draft of the
facilities plan was completed. An initial assessment of the
treatment plant indicated that for the short term, supplemental
aeration was needed in the lagoons, especially during cold
weather when the lagoons could freeze. In addition, improvements
to the preliminary treatment system were identified.
West Yost provided a facility assessment for the original design
of the 0.16 mgd, Flag City Wastewater Treatment Plant (WWTP).
This work included an evaluation of the disposal capacity of the
onsite storage pond, and an evaluation of several long-term
disposal and reuse options. Through this study, it was determined
that continued land disposal in the short-term was not feasible.
Therefore, this study culminated in the development of an NPDES
permit application and Report of Waste Discharge to allow for
surface water discharge. West Yost provided support services
throughout the permit renewal process, including negotiations
with Regional Water Quality Control Board staff, and data
analysis.
West Yost was commissioned by the Central Valley Clean Water
Association (CVCWA), to evaluate whether various wastewater
treatment processes can achieve stringent water quality-based
permit limits being applied to municipal dischargers in the
Central Valley of California.
The NPDES permit assistance performed by West Yost for
the City of Vacaville included preparation of a Report of Waste
Discharge and NPDES permit application, and subsequent
negotiations with the Regional Board regarding the NPDES permit
requirements. The NPDES permit adopted was the first permit in
the State to incorporate the requirements of the Policy for
Implementation of Toxics Standards for Inland Surface Waters,
Enclosed Bays, and Estuaries of California, 2005 (SIP).
West Yost provided a facility assessment for the original design
of the 0.16 mgd, Flag City Wastewater Treatment Plant (WWTP).
This work included an evaluation of the disposal capacity of the
onsite storage pond, and an evaluation of several long-term
disposal and reuse options. Through this study, it was determined
that continued land disposal in the short-term was not feasible.
Therefore, this study culminated in the development of an NPDES
permit application and Report of Waste Discharge to allow for
surface water discharge. West Yost provided support services
throughout the permit renewal process, including negotiations
with Regional Water Quality Control Board staff, and data
analysis.
West Yost assisted the City of Medford with their development of
using treated wastewater for agricultural irrigation. This effort
has been in response to increasingly stringent discharge
requirements imposed by DEQ for discharge of effluent to the
Rogue River. West Yost developed the facilities plan which
recommended that the City further evaluate reclaimed water
production to reduce the impact of pending TMDLs on the Rogue
River.
West Yost designed a major expansion to the City of Creswell’s
effluent reuse program. A three-mile-long force main was designed
to deliver water to a newly purchased 215 acre reuse site. A new
reclaimed water pump station was designed as part of the
treatment plant design. The pipeline included a crossing of Camas
Swale Creek for which an Army Corps of Engineers 404
permit and a State Lands Division permit were obtained.
West Yost is assisting the City of St. Helena in the development
of the best compliance solution for several outstanding
regulatory issues associated with their 0.5 mgd Wastewater
Treatment Facility (WWTF), including an evaluation of the City’s
water reuse options.
