SS9901-CS010710TurnerCollie 'Braden Inc. MEETING MINUTES
Subject: DeForest and Sandy Lake Wastewater Lift Stations and Force Mains Improvements
Job No.: 15 31124 001
Place: City of Coppell
Date of Mtg.: July 10, 2001
Attendees: Ken Griffin - Coppell Bob Reach - TCB
Glenn Hollowell - Coppell Ted Sugg - TCB
Ted Duck - Coppell Jennifer Ratcliff- TCB
Date Prepared: July 10, 2001
Prepared By: Jennifer Ratcliff
1. Review Report
· Ken asked if it was necessary to keep the existing 16" force main in place from DeForest.
It was determined that the 16" force main would remain in place for use in an emergency
or during maintenance of the new 30" force main.
2. Review Recommendations
a. DeForest Wastewater Lift Station
· Ken likes the proposed location of the new lift station because it is further from the
existing homes.
· The City wants the brick wall to be at least 20 feet from the new lift station structure on
all sides.
· Ted D. is concerned about the recommendations for the SCADA system at both lift
stations. The Preliminary Design Report is not very specific. The City wants to be very
specific about the type of system to be installed. They want the new system to be the
same as the existing system.
· Bob suggested that the City meet with the electrical engineer during final design to
discuss the specific details of the control system to ensure that the plans specify a system
the City will be happy with.
· Glenn and Ted D. do not want to use VFDs. They would prefer constant speed pumps at
both lift stations.
b. Sandy Lake Wastewater Lift Station
· Ted D. would prefer to pump around Sandy Lake during the renovation process to avoid
using the dry well as a temporary wet well. This should be feasible if the new DeForest
lift station and related force main are built first so the flow at Sandy Lake is reduced.
· Glenn and Ted D. would prefer to purchase and install 3 new pumps for Sandy Lake
instead of using 2 new pumps and the existing Ingersoll Dresser pump.
c. Force Main Alignment
· Ken asked why the force main alternative that was recommended (FM-8) is not one of
the least expensive. It was explained that when looking at the total construction cost of
the entire system (lift stations and force mains), FM-8 is the second lowest cost with only
FM-5 lower. However, FM-5 would have hydraulic problems due to low velocities
through the force main when the Sandy Lake Lift Station is operating and the DeForest
Lift Station is off.
DeForest and Sandy Lake Wastewater Lift Stations and Force Mains Improvements
July 10, 2001
Page 2
· Ken is concerned about the alignment's effect on the trees in the median of MacArthur
between DeForest and Sandy Lake. Ted S. said this will be addressed in final design,
and the trees will be avoided wherever possible or the force main will be bored under the
trees. However, along MacArthur on the south end of the force main, the trees will be
removed as part of a planned roadway widening nroject, so open cut can be used.
· Ken said there is a new 30" water line in C-5.m~ll Court that may complicate the
alignment along that street. There are also 16", 30", and 36" water lines that would have
to be crossed· The existing 30" water line to be crossed is approximately 18' deep and
the 16" is approximately 6' to 8' deep. Glenn suggested open cut installation and
encasemento ,,~~
· It was also suggested that 1 Court be avoided by going along the perimeter of the
pump station. This alignment would only require crossing one water line.
· Along MacArthur just north of Belt Line, there is a CMAQ project which proposes to
remove the existing median to add a second left turn lane. It would be best if the force
main could be constructed prior to the proposed turn lane. TCB should contact Ivan
Nicodemus to find out when the CMAQ construction is scheduled and whether or not the
force main construction can be added to the CMAQ construction.
· An alternate route was suggested along Riverchase to avoid the CMAQ project, but it
was determined that there isn't enough room to construct the force main between the
shopping center on MacArthur and the apartments east of the shopping center.
· The City would prefer that the force main be tunneled under the median openings in
MacArthur to avoid removing existing pavement.
d. Odor Control
· The City wanted to know why drum scrubbers were recommended instead of the carbon
adsorption system (which is the current method of odor control at DeForest). Bob
explained that the carbon adsorption system is not as reliable in humid conditions as the
drum scrubber. Also, the media from the drum scrubber is non-hazardous and therefore
easier to dispose. Ken wants to make sure that the ventilation point is higher than the
rooftops in the neighborhood.
· Ken asked about venting along the force main. Bob said ventilation through an air
release valve may be necessary at the high points. Ted D. said the air release valves are
not difficult to maintain. They only need to be checked every 6 months.
e. Generators · Bob is concerned about the noise made by an on-site generator and does not think one
should be located at DeForest.
· The City has decided not to purchase on-site generators as part of this contract.
3. Construction Contracts
a. Lift Stations
· The City would prefer to have one construction contract for both lift stations together.
b. Force Mains
· The City would prefer to split the force mains into three construction contracts.
· The first contract (and first priority) is the section of 30" force main going south from the
Sandy Lake Lift Station to the TXU easement. St. Joseph's has agreed to provide the
City with a 30' easement under their fire lane along this alignment. The City would
DeForest and Sandy Lake Wastewater Lift Stations and Force Mains Improvements
July 10, 2001
Page 3
prefer to construct the force main prior to construction of the fire lane which is scheduled
for fall 2001.
· The second contract is the section of 20" force main along the median of MacArthur
from Bethel School Road to Belt Line. In addition to the CMAQ project at Belt Line, the
City is planning to tear out the median to add a third southbound lane in MacArthur. The
City would prefer to construct the 20" force main at this time and possibly as part of the
City's widening contract.
c. Generators
· No contract will be required for on-site generators.
4. Final Design Authorization
a. Notice to Proceed
· The City approved the recommendations in the Preliminary Design Report and gave
verbal notice to proceed with final design.
· Ken will prepare and send an official Notice to Proceed the week of July 23.
b. Surveying
· Bob asked if the City would approve of aerial survey. Ken asked about the accuracy of
the aerial survey. The aerial survey is accurate to within 1 foot horizontally and the
desired accuracy can be specified for vertical measurements. The aerial survey would be
supplemented with ground survey to tie down flow lines, etc. Ken and Glenn will accept
aerial surveying as long as the plans provide the contractor with enough information for
construction.
· The engineering and surveying costs were originally based on 14,000 LF of force mains.
The length of force main required has increased to approximately 16,000 LF. Therefore
additional funds may be necessary for engineering and surveying. TCB will evaluate this
requirement and advise the City. Ken said the City would review and consider a request
for additional authorization.
c. Geotechnical Engineering
· Once the surveying and geotechnical engineering are completed, the preliminary layout
for DeForest will be prepared and reviewed with the City before proceeding with the liR
station final design.
d. Design Standards
· The City prefers a 1"=20' scale on plan/profile drawings. They also prefer 22"x34"
sheets so they can be reduced to half size on 1 l"x17" sheets.
e. Easements
· The City is in the process of obtaining a 30' easement from St. Joseph's just east of
Sandy Lake for the new 30" force main.
· It may be necessary to obtain an easement from TXU for the proposed, alignment of the
new 20" force main. Ken thinks this may be difficult because TXU does not want other
utilities to parallel their lines, although he said there is an existing 42" water line in the
TXU easement. He suggested looking at putting the new 20" force main along the east
side of the TXU easement.
· Glenn suggested looking into connecting the existing 6" and 8" sewer lines from
MacArthur between Condor and Starleafto the new 20" force main discharge point.
From MacArthur, it may be possible to convey the flow from Sandy Lake by gravity to
DeForest and Sandy Lake Wastewater Lift Stations and Force Mains Improvements
July 10, 2001
Page 4
the TRA line. However, because this is a high point along MacArthur, the line may have
to be very deep, so this alignment may not be feasible.
· The next step is to contact TXU (Ken provided Ted S. with a contact name and number)
to see if they will allow the proposed force main in their easement.
Bob pointed out that easement preparation is not part of the scope of work. However,
TCB can perform this task as an additional service, if required.
5. TRA Coordination/Permit
· Ken asked if the new 20" force main would tie into the existing 30" TRA line or the
existing 33" TRA line. Bob explained that the Preliminary Design Report shows the 20"
force main tying into the 33" TRA line, but the actual connection point would be
coordinated with TRA during final design.
Bob asked if the City would prefer that TCB coordinate with TRA directly or through the
City. Ken said he would prefer that TCB coordinate directly with Randy Brooks of TRA.
6. Schedule
a. Design
· Bob thinks the third force main contract and the lift stations contract should be ready for
bid in the second quarter of 2002.
· The first force main contract (through the St. Joseph's tract) should be designed as soon
as possible so it will be ready for construction in fall 2001.
b. Construction
· The City does not think that the season will have much impact on construction.
· Ken is concerned that the construction cost estimate is too low. Bob said a more detailed
construction cost estimate will be prepared once survey information is available. Ken
wants to be kept informed if the construction cost estimate increases.
· Ken said the City has $2.5 million available for the DeForest Lift Station and force main,
and will be able to get another $1 M for Sandy Lake Lift Station and force main.
Distribution: File
Attendees