HomeMy WebLinkAboutItem 05 - SH 114/SH 121MEMO TO
FROM
MEETING DATE:
SUBJECT:
RECOMMENDATION:
ITEM 0
HONORABLE MAYOR AND MEMBERS OF THE CITY COUNCIL
ROGER NELSON, CITY MANAGER4/
FEBRUARY 3, 2004
ENGINEERING SERVICES CONTRACT AMENDMENT — SH
114 / SH 121 MIS
City Council consider approving an amendment to the existing consultant engineering
services contract with Turner, Collie & Braden, Incorporated (TC&B) relative to the SH
114 / SH 121 MIS project in an amount not to exceed $50,000.00, authorize staff to
execute said amendment and take any necessary action.
FUNDING SOURCE:
Funds for this contract amendment are available in 03 GO Bonds, Account No.: 178-
78107-015
BACKGROUND:
The development of the SH 114 / SH 121 MIS has continued to be a very labor-
intensive undertaking in both City Staff time and consultant's time.
City Council has previously approved a contract with Turner Collie & Braden,
Incorporated on June 18, 2002 in the amount of $50,000.00 for Traffic Analysis Services
in the SH 114/ SH 121 Corridor and an amendment on August 19, 2003 in the amount of
$27,360.00.
Since June, 2002, TC&B has developed additional access routes and interchange
configurations at various locations throughout the corridor and prepared preliminary
schematics of the more complicated additions. These additions were developed and
specific trouble spots were analyzed utilizing NCTCOG 2025 traffic volumes and
operations -specific computer models to insure that they were viable proposals.
The proposed additions were incorporated into the NCTCOG Model with some
additional access modifications suggested by the NCTCOG Staff.
O:\agenda\8-19-03\MIS Engr Amendment TC&B
January 28, 2004 (1:32PM)
TC&B completed their tasks and the access and interchange configuration was
proposed to TxDOT based upon 2025 traffic projections available at the time.
Subsequent to this submittal, TxDOT Staff in the Austin office prepared 2025 traffic
projections for the corridor that were dramatically higher than any seen prior to that time.
With these much higher volumes, portions of the City's access and interchange proposal
were not feasible.
City Staff and NCTCOG Staff attended numerous meetings to reconcile the TxDOT
volumes with NCTCOG's volumes. That task has been completed with agreed upon
volumes much closer to NCTCOG's projections. NCTCOG Staff has included the
proposed access and interchange configurations into their traffic model and the model
has assigned traffic volumes to each of the individual elements of the proposal.
Through the use of more site-specific, operations -oriented computer models, TC&B
confirmed that the desired access locations were feasible with the agreed upon 2025
traffic volumes, identified any necessary geometric changes from the initial proposal,
and reviewed recommendations with City Staff.
Prior to presenting the final recommendations to NCTCOG Staff and TxDOT Staff, a
revised set of 2025 volumes dated September 15, 2003 were generated by NCTCOG
utilizing updated demographic projections. These revised 2025 volumes are now the
official volumes for planning all future projects funded through NCTCOG in the
Metroplex.
TC&B must now:
• convert the revised 24 hour traffic volume assignments from the new 2025 volumes
to design hourly volumes
• reanalyze critical weave sections north of DFW Airport with the new 24 hour traffic
assignments
• reanalyze levels of service (LOS) using highway capacity software to confirm validity
of access additions north of DFW Airport using VISSIM software
• reanalyze levels of service (LOS) using highway capacity software to confirm validity
of access additions west of International Parkway
• analyze LOS for the FM 1709 / SH 114 / Northwest Highway Interchange using
Synchro software
identify geometric options to address new volume assignments
0:\agenda\8-19-03\MIS Engr Amendment TC&B
January 28, 2004 (1:32PM)
0 review reanalysis and geometric options with City Staff and NCTCOG Staff.
0 incorporate preferred geometric changes into SH 1141 SH 121 Schematic.
TC&B and City Staff will present final recommendations to NCTCOG Staff, then meet
with TOOT Staff to discuss the proposed access package. This will insure that the
City's access and interchange proposal will function satisfactorily from a geometric as
well as an operational perspective before we submit the final package to TOOT.
City Staff is attempting to expedite the MIS process and receive environmental
clearance for this project as soon as possible.
Staff recommends approval.
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