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A 628 gpm sewage lift station and 1,480 feet of 8" force main were
designed for the City of Sapulpa to serve a new residential subdivision
and surrounding areas.
The design included a determination of the lift station site and force
main route. Design considerations for the lift station included sizing
the pumps and motors, sizing the wet well, storage calculations, buoyancy
check, and capacity of downstream gravity sewers and lift station.
The project is to be constructed in two phases. The project components
were sized for alternate use wherever practical.
Special consideration was given to keeping the existing lift station in
service during construction. Also, the existing wet well was retained
for emergency holding capacity.
Project List
The purpose of this project was to design a replacement for a 6,000
foot, forty-year old, 16" sewage force main in north Tulsa. A major
project constraint was to keep the existing force main in service until
the switch to the new force main could be made. The lift station could
only be taken out of service for a short time during low flow.
The firm designed the pipeline to accommodate two alternative pipe materials
- ductile iron and high density polyethylene (HDPE). The line was routed
to minimize the need for new easements. We prepared an easement for the
area through property owned by Tulsa County.
Route survey was performed by in-house survey crews.
Other services included preparing an engineering cost estimate and writing
a special specification section for HDPE pipe. There were two creek crossings
on the project.
We attended the bid opening, tabulated bids, and made recommendation of
award. When the project was completed, we prepared record drawings.
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The firm was hired to design sanitary sewer service to an unsewered area
bounded by 36th Street North and Highway 11 and Highway 75 and North Harvard.
The firm provided a property search to establish all property owners and
existing rights-of-way and easements. A preliminary route location was
made to demonstrate that all property owners that had petitioned the City
for sewer service could be sewered. We prepared exhibits and attended
a public meeting to discuss the project with the residents. The locations
of the sewer lines was revised according to information received from
the public.
Construction plans and specifications were then developed and the project
was bid. The profiles were developed using information from in-house survey
crews. We provided easement descriptions and plats as required for the
new sewer lines. General services during construction were provided including
bidding assistance, submittal review, pay request review, and periodic
inspections.
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The firm completed an engineering study and design of an outfall sewer
to serve the west side of Skiatook. The outfall opened up a large area
for development and allowed Skiatook to eliminate an existing lift station.
During the study phase, future sewage flows were projected and a final
route was selected. Easement requirements were identified.
Construction plans and specifications were produced during the design
phase. We also prepared all easement plats and descriptions. Sewer sizes
and slopes were designed to meet the ultimate flow requirement. The final
project included about 13,000 linear feet of 18" pipe, almost 1,500
linear feet of 15" pipe, three road crossings, and forty manholes.
Bidding and Construction Phase services included bidding assistance, bid
tabulation, preconstruction conference, submittal review, periodic inspection,
pay request review, final inspection and as-built drawings.
Project List
The firm designed improvements to the Dewar four cell lagoon system,
which included the following:
18" sanitary outfall
New flow splitter box
Demolition of existing by-pass drains
Fencing
Rehabilitation of a discharge flow structure with weir
Reshaping of lagoon slopes and dikes
Placing gravel on top of dikes
Sludge removal with land application of sludge
The project was bid in two packages. One contract was for the rehabilitation
work and the other was for the sludge removal and land application.
General services during construction included bidding assistance, Prework
Conference, submittal review, pay estimate review, periodic and final
inspection and as-built drawings.
Project List
An engineering study was conducted for the Tenkiller State Park sewage
system. Items investigated included existing pump stations, force mains,
gravity lines, and total retention lagoons. Specific problems included
old pumps, wet wells below the lake flood pool elevation, lagoons which
overflow and leak, inflow sources, inadequate area for lagoons and plumbing
fixtures that do not conserve water.
Eight new pump stations were designed. One of the pump stations was specifically
designed to be water resistant during high water periods. New lagoons
with about 9 acres of surface area were designed to replace the existing
lagoons, which had less than three surface acres.
A sludge management plan for beneficial reuse of the sludge by land application
was prepared. The plan was for disposal of the sludge in the existing
lagoon cells.
The size of the new cells was minimized by designing supplemental land
application by spray irrigation.
A Stormwater Pollution Prevention Plan was written including an erosion
control plan.
All field surveys were done with in-house crews using total station and
GPS equipment.
Project List
The firm acted as the College's consultant in response to a notice of
violation from the Department of Environmental Quality (DEQ). A study
was conducted to investigate existing problems concerning the sanitary
sewer collection system comprised of 30 manholes and 8,020 linear feet
of 8" line, most of which was constructed when the College was originally
built.
Inspection and testing in Phase I of the evaluation included physical
inspection of all manholes, smoke testing of the entire system and electronic
flow measurement of a critical manhole over a period of two months which
included dry and wet periods. A detailed infiltration/inflow analysis
was performed on the entire collection system to develop hydrographics
and evaluate the extent of infiltration/inflow on the system.
The existing lagoon was analyzed and alternatives were investigated to
determine the optimum manner in which to increase the lagoon's treatment
capacity and to bring the lagoon into compliance with DEQ regulations.
Other services included making recommendations on tying the College sewer
system to the Wilburton Municipal Sewer System. A detailed report was
submitted to EOSC.
Phase II of the sewer system study included cleaning and television internal
inspection of 5,200 linear feet of 6" and 8" line. The firm
coordinated the work and incorporated the results of the inspection into
a final report which included specific rehabilitation recommendations
as a basis for construction plans.
The final phase of the project included the preparation of plans and specifications
for the recommended rehabilitation of the existing sewer system, including
slip-lining, manhole rehabilitation, replacement lines and point repairs.
Services during bidding and construction were provided.
Project List
Sanitary sewage flow was monitored at fourteen locations in Claremore
for a period of 90 days. Badger flow meters were used along with four
electronic rain gages which were recorded by four of the flow monitors.
The City was divided into thirteen subbasins for the study. Flow hydrographs
were developed for wet and dry conditions for each of the subbasins. This
information was used to develop unit hydrographs for use in a computer
model of the sewage collection system.
All pipes 10" and larger were input to a computer model which was
used to predict potential overflow locations. All manholes were numbered
for use in the model and for future identification.
Based on the information gathered, peak flows were predicted for rainfall
events. The subbasins were ranked in terms of infiltration and inflow
per inch diameter mile of pipe.
As a part of the study, four lift stations were evaluated. The pumping
rates were calculated by drawdown tests. Recommendations were made concerning
adequacy and potential problems.
As a result of the study, the City was prepared to proceed to a physical
investigation and television inspection phase.
Project List
The firm was retained to provide a route location study for 20,000 linear
feet of sanitary sewer relief main from 55th and Delaware to 29th and
Yale in the City of Tulsa. The contract included final design of the portion
from 55th and Delaware to 38th and Sandusky. The original sanitary sewer
line had chronic overflow problems at numerous manholes locations during
times of heavy rainfall due to storm water infiltration. The original
sanitary sewer line went through a highly urbanized part of the City,
containing both commercial and residential development, and included the
crossing of Joe Creek concrete lined channel, primary arterial streets,
and a section of interstate highway.
The diameter sizes of the sewer relief main were designed to be 15, 18,
21, 24 and 30 inches, depending on the anticipated storm water infiltration
of the original sewer. Cross-connections were determined at key locations,
allowing the maximum amount of storm water to be discharged into the new
relief sewer main.
Several route locations were analyzed to determine the least cost and
the best maintenance accessible. Because part of the construction was
to take place in an older established residential area, special consideration
was given to the property owners' concerns, such as the prevention of
damage to trees, driveways, and streets. Borings were specified whenever
the relief line passed beneath the drip line of a large tree, special
structure or obstacle that was of concern to the property owner or the
City of Tulsa.
In-house survey crews were used for the design survey. Detailed location
surveys and profiles were done. Also, property surveys were needed to
locate property corners. Easement descriptions were prepared for portions
of the line placed outside existing right-of-way or easements.
All types of manholes, i.e., standard, drop, special design and manhole
connections, were used in this project. Special designs for oversize manholes
were used when both the existing line and relief line were to be in the
same structure.
Construction services provided by the firm include bidding assistance,
bid tabulation, preconstruction conference, shop drawing review, periodic
inspection, resident inspection, construction staking, contractor's pay
request review, final inspection and as-built drawings.
Project List
The firm was retained to design sanitary sewer rehabilitation and lagoon
rehabilitation for the town of Fairland, Oklahoma, in response to a Consent
Order from the Oklahoma State Department of Health. The NPDES permit limitations
were being exceeded at the Town's flow-through lagoons and one of the
potable water wells was testing above limits for radium.
Design was based on several studies done by the firm. The first study
included flow monitoring, smoke testing and physical inspection of the
system to determine infiltration and inflow effects. Recommendations were
made concerning which lines and manholes should be rehabilitated or removed,
etc.
The second study addressed the beneficial reuse of sludge by land application.
The two older lagoon cells were to be cleaned by removing the sludge.
The beneficial reuse study investigated the feasibility of land application.
Application rates were determined, and suitable farm land was located.
Removal methodology was developed and described in the study.
Plans and specifications were developed which reflected the recommendations
of the reports. Approximately one mile of 8" and 10" gravity
sewer was replaced and 2,000 feet of 6" force main was installed.
The contract also called for 11,000 feet of cleaning and TV inspection.
Other services included bidding assistance, bid tabulation, prework conference,
submittal review, pay estimate review, periodic and final inspection and
as-built plans.
All work was done in strict compliance with requirements and time schedules
set forth in the Consent Order.
Project List
The firm was responsible for the planning and design of a sewage collection
and treatment system to serve a previously unsewered area. Facilities
included 8", 10" and 21" gravity sewer pipe, 10" pressure
pipe and a sewage lift station. The system was designed to serve an ultimate
area of about 750 acres. A preliminary study was done to allow accurate
sizing of facilities based on developable land and actual topographic
characteristics. All field surveying was done in-house using Zeiss self-leveling
level and optical electric distance measuring device mounted on a Wild
T2A 5-second theodolite.
The sewage treatment facility consisted of a four-cell lagoon system.
Due to the initial low flows anticipated, the system acted as a total
retention lagoon in the early stages of development. It was designed to
be converted to a flow-through system when flows increased. At maximum
design flows, aerators can be added and the depth increased with weir
to allow the system to function as an aerated flow-through system.
Complete construction plans were prepared with specifications and cost
estimates. Services during construction included construction staking,
periodic inspection, pay estimate review, final inspection and as-built
drawings.
Project List
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