ST9904-CS001011 121 - WEST SECTION 10/11/00
Project Limits: From SH 121 Business to West of Lake Vista Drive
Project Length: 2.60 Miles
Estimated Cost: $27.0 Million
General Discussion: The project consists of adding freeway main lanes and ramps inside of the existing
frontage roads. The project will ultimately be a six lane divided freeway designed for 70 mph. Auxiliary lanes
are provided between Denton Tap and MacArthur ramps and also between MacArthur and Lake Vista ramps.
Major intersections are provided at Denton Tap Road, MacArthur Boulevard and Lake Vista Drive. Traffic
signals will be modified at Denton Tap and MacArthur. Traffic signals will be added at Lake Vista Drive.
Existing crossovers at Ridgemont and Rockbrook will be closed. New bridges will be provided at the overpass
at Denton Tap Road, the stream crossing east of Ridgemont, the overpass at MacArthur, and the stream crossing
east of MacArthur, a total of 8 structures. The overpass at Lake Vista Drive is included in the IH 35E
interchange project currently under design by TxDOT. Retaining walls will be included at MacArthur
Boulevard and on the west side of Lake Vista Drive. The existing frontage road drainage system is in place and
all drainage outfalls for the project have been provided. Traffic control and lane closures should be limited to
points where ramps connect with frontage roads and where new bridges will cross over Denton Tap Road and
MacArthur Boulevard. The construction sequence plan will minimize lane closures to the extent possible.
Notice to Proceed: Anticipated start date - November 1, 2000
Design Duration: 18 months
Completion Date: Anticipated completion date - May 1, 2002
Design Team: Halff Associates is the prime consultant, Sub-consultants include Wendy Lopez Associates for
surveying and drainage, Ibarra Consulting Engineers for utility coordination, C&P Engineering for traffic signal
design, Terra Mar for geotechnical engineering and Swift Technologies for project web site.
Exhibit "B"
Engineering Cost Estimate for 121 from 35E west to 121 Business
Paving, Drainage and Bridge Improvements (13,700 LF)
Halff Associates Inc.
August 2000 AVO 1008.00.0898
Item No. Description Quantityunlt Price Amount
i Grading 810,382 CY 6.00 84,862,292
2 Pavement - mainlanes 121,053 SY $75.00 $9,078,975
3 Pavement - ramps 8,043 SY $100.00 $804,300
4 Pavement - shoulders 62,028 SY $40.00 $2,481,120
5 Erosion control 1 LS 150,000.00 $150,000
6 Traffic control 1 LS 200,000.00 $200,000
7 Drainage 13700 LF 150.00 $2,055,000
8 Signals 3 EA 100,000.00 $300,000
9 Bridges 1 LS 5,296,700.00 $5,296,700
10 Striping and signage 1 LS 500,000.00 $500,000
Subtotal $25,728,387
Cost contingency 5% $1,286,419
Total Cost $27,014,806
CONSTCOST 1 10/9/00
ATTACHMENT B
SERVICES TO BE PROVIDED BY HALFF ASSOCIATES - (THE ENGINEER)
PROJECT DESCRIPTION: West of 114 35E the project currently has three lane frontage roads
in each direction. The main lane structure that will cross IH 35E will begin at station 2207+00,
west of Lake Vista and end at station 2283+00 east of the Elm Fork of the Trinity, a total
distance of 7,600 feet. This structure is to be built as part of the SH 121/IH 35E interchange and
is not part of the design section. The SH 121 improvement project comprises construction of
main lanes and ramps in this section constructed fully between the existing frontage roads.
Interchanges are proposed at Lake Vista, MacArthur and Denton Tap Road. All of the
interchanges in the section are overpasses. Traffic control will be minimal except at intersections
where new bridges will be constructed. The majority of the earthwork in this section will be fill.
A large header bank for the main lane construction is already in place at the west side of Denton
Tap Road.
Drainage outfalls include Denton Creek at the west end of the project and a newly constructed
improved channel near the center of the project. Drainage design for the project will be
coordinated with the newly constructed frontage road plans.
The project ends at the interchange with SH 121 business. The majority of the interchange at SH
121 business has been constructed, leaving the main lane connection to be completed.
Signals currently exist at MacArthur and Denton Tap Road, un-signalized crossovers include
Lake Vista, Rockbrook and Ridgemont. Both Rockbrook and Ridgemont crossovers will be
closed by the construction. Design of temporary and permanent signals may be included in the
project design. A signal at Lake Vista should be considered due to inadequate sight distance to
the west, which will become more of a problem during construction, as the wall and header bank
on the west side is constructed. Additionally in the vicinity of Lake Vista and also at MacArthur
the right-of-way narrows thus requiring retaining walls to be considered as part of the SH 121
improvements.
SCOPE OF SERVICES
Right of Way Data (130)
* Utility Adjustments
· Highway design data shall be furnished for Utility Adjustments and ROW determination as
required
Roadway Design Controls (160)
Field Surveying and Photogrammetry
· Field Surveying
· Primary Project Control
· Establish horizontal control points
· Establish vertical control points
· Secondary Project Control
· Project control base lines
· Photogrammetric ground control
· Other field surveying
· Measure ties to STATE ROW monuments or to angle points in existing ROW line
· Establish bench mark circuit throughout the project
· Cross section drainage channels
· Tie existing underground and overhead utilities (location, elevation, and direction), includes
location of accessable ground utilities only
· Obtain elevation of manholes and valves of utilities
· Pavement Design
· Geometric Design
· Horizontal and vertical alignment
· General Guidelines for Project Development
· Grading Design
· Horizontal and vertical alignment
· Typical sections
· Design cross sections
· Determine cut and fill quantities
Drainage (161)
· Hydrologic Studies, Discharges
· Drainage area maps showing existing conditions and proposed improvements
· Hydrologic data/discharge determination
· Hydraulic Design and Documentation
· Hydraulic computations
· Layout, Structural Design and Detailing of Drainage Features
· Culverts
· Storm sewers
· Subsurface drainage at retaining walls
· Storm Water Pollution Prevention Plan (SW3P)
Signing, Markings and Signalization (162)
· Signing and Markings Layout
· Summary of Small Signs Tabulation
· Summary of Large Signs Tabulation including all Guide Signs
· Sign Detail Sheets
· Traffic Signals
· Layout
· General requirements
· Summary of quantities
Miscellaneous (Roadway) (163)
· Foundation Studies
· Retaining Walls
· Structural details
· Retaining wall layout (PLAN)
· Retaining wall layout (ELEVATION)
· Estimate
· Summary of quantities
· Typical x-section
· Traffic-Control Plan, Detours and Sequences of Construction
· Miscellaneous Drafting/Standards
· Compute and Tabulate Quantities
· Miscellaneous Structures
· Estimate
· Specifications and General Notes
Bridge Design (170)
· Foundation Studies
· Preparation of Structural Details
· Preparation of Bridge Layouts
· Bridge layouts (PLAN)
· Bridge layouts (ELEVATION)
· Additional layout requirements for waterway structures and bridge classification culverts
· Bridge Classification Culvert Details, Estimates, Quantities, and Specifications
· Bridge Total Quantities and Cost Estimates
· Bridge Special Provisions and Specifications
· Bearing Seat Elevations
· General Guidelines for Bridge Design
Additional Responsibilities
· Easements, Letters of Permission, etc.
· Coordination of Utilities
· Meetings
· Specifications, special provisions, special specifications
· Project Manager/Engineer Communications
· The engineer shall designate one Texas Registered Professional Engineer to be responsible
throughout the project for project management and all communications, including billing,
with the State's Project Engineer. Any replacements to the engineer's designated Project
Manager/Engineer must be approved by the State. Engineering documents produced for the
department's engineering projects shall be signed, sealed and dated or CADDSEALED in
accordance with Administrative Order No. 5-89 and Administrative Circular No. 26-91.
· Engineer shall establish a project web site for the duration of the project
.... I ol g,3o
121 - WEST SECTION
Project Approach
1. Obtain aerial survey from TxDOT, supplement with on the ground topography where needed, survey
and map the right of way and existing utilities. Perform geotechnical testing.
2. Coordinate any required utility relocations.
3. Layout horizontal and vertical alignment for main lanes and ramps. Develop cross sections, bridge
layouts, retaining wall layouts and horizontal and vertical alignment for storm drainage systems.
4. Prepare traffic control and sequence of construction plans, main areas of focus will be the intersections
with Denton Tap Road, MacArthur and Lake Vista.
5. Prepare structural details for culverts, bridges and retaining walls.
6. Layout signage, striping, signals, erosion control and other miscellaneous items.
Design Team: Halff Associates is the prime consultant, Sub-consultants include Wendy Lopez Associates for
surveying and drainage, Ibarra Consulting Engineers for utility coordination, C&P Engineering for traffic signal
design, Terra Mar for geotechnical engineering and Swift Technologies for project web site.
SH 121 Existing-Denton County