West Yost under contract to an environmental services firm,
provided engineering design and construction period
services for converting 217 acres of rice farmland into a
wetlands and endangered giant garter snake habitat. The wetland
will rely on two water sources: agricultural delivery and an
onsite supplemental groundwater well.
Water balances were developed by WYA to determine the required
water supply for the project and to establish the optimal
capacity of the backup irrigation well.
West Yost reviewed previously prepared technical studies and
schematic-level designs of two design alternatives to handle
overland drainage in the Soscol Gateway area of Napa. Following
this review, West Yost developed an alternative drainage plan
that had an estimated cost of about $6.4 million, nearly a 50%
cost savings from the previously developed project (at about $12
million). In addition, the performance of this alternative, low
cost approach was verified as better than the performance of the
previous plan.
West Yost designed a stormwater pump station serving the Opus
Logistics Center in east Stockton. The project consists of the
construction of a below grade stormwater pump station with a
rated capacity of 44 cfs.
West Yost prepared a Storm Drain Master Plan for the City of
Manteca and subsequently prepared the predesign
and design of a detention basin, pump station, and box
culvert. The 16 ac-ft detention basin included a 4 cfs pump
station and nearby irrigated landscape and hardscape. Design also
incuded 1,500 feet of a 3’ x 12’ box culvert, and 1,100 feet of a
3’ x 8’ box culvert with associated sewer relocations.
West Yost performed a master drainage study for the City and
subsequently assisted the City in designing and constructing a
number of infrastructure projects including the Vally Glen
Stormwater Pump Station. The 156-cfs storm water pump station
included trench style concrete wetwell, mechanical “flexrake”
trash rack, four propeller duty pumps with low speed motors, and
one low flow pump.
West Yost performed a master drainage study for the City with
complete review and analysis of applicable hydrologic models and
development of a recommended Capital Improvement Program. West
Yost also provided planning and design services for storm
drainage infrastructure including detention ponds and pumping
stations.
West Yost provided a feasibility study, predesign, and final
design for two regional detention facilities to reduce flooding
in the City of Vacaville. This project included two basins
located on either side of Encinosa Creek (tributary to Alamo
Creek). The recommended detention basins have a combined
detention storage capacity of 200 acre-feet.
After preparing the VSFCD Flood Control Master Plan, West Yost
provided on-call modeling and design services on serveral
projects for the District. This included preparing the design of
a headwall, trash rack, and access road for an open channel
within Setterquist Park, reviewing a Caltrans plan to enlarge
three culverts under I-80, and developing a low-cost storm
drainage improvement plan to address increased flows through the
Caltrans culverts.
West Yost prepared the design of Phase 1 of the Homeacres
Drainage Improvements. These projects included design of 18-inch
to 30-inch storm drains through areas congested with other
existing underground utilities, a 48-inch storm drain, and a
tailwall and velocity/energy dissipater section of riprap. The
project included design of an earth berm 3 feet high and a
headwall/drain inlet and curb and gutter at several locations.
West Yost prepare a detailed design and specifications
for flood control improvements to address flooding following
a December storm event. The project involved addressing changes
within the watershed since the District’s Storm Drainage Master
Plan was prepared. West Yost developed updated modeling which
closely reproduced the actual flooding observed from the December
storm, and conducted a detailed evaluation of alternatives,
resulting in recommendations and ultimately design of a 2,600
feet of 96-inch bypass pipeline through a congested industrial
area (in soft bay mud).
West Yost provided planning, analysis, environmental review,
permitting, design, and construction management services for the
Dry Creek WWTP Levee Relocation. This project included the
hydrologic and hydraulic analyses of Dry Creek in the vicinity of
the WWTP. The project provides 100 year protection of the
wastewater storage ponds while enhancing the flow carrying
capacity of Dry Creek in an environmentally sensitive manner.
