17-144 - 144th Avenue Widening – Washington Street to Franklin Street, Project No. 17-144

Project Description:  Thornton requires that the following Engineering and Design Services be performed by the Consultant as it relates to the above-referenced Project and constitutes the basis for this Agreement.
 
The Services include the engineering, surveying, planning, and coordination necessary to construct the widening of 144th Avenue from Washington Street to Franklin Street.
 

• The 144th Avenue typical roadway section will include two (2) travel lanes in each direction from Washington Street to Franklin Street, and will taper from a proposed five (5) lane section at Franklin Street to the required four (4) lane section west of Franklin Street, across most of the Big Dry Creek floodplain.
• A continuous center turn lane will be added west of the Big Dry Creek crossing for the existing oil and gas access to the south; widening into the dual left lanes at the newly constructed intersection at 144th Avenue and Washington Street.
• Curb and gutter will be installed along 144th Avenue where needed for stormwater drainage purposes.  If possible, it is desired that open shoulders exist, if drainage swales can be contained in the Right-Of-Way (ROW).
• The existing width of 144th Avenue will be milled, overlaid, and restriped within the Project limits.
• One (1) bike lane shall be included in each direction from Washington Street to Franklin Street.
• Electrical drawings and coordination required for Project streetlights.
• Coordination with school or property owner for potential right turn into Stargate.
• The Consultant shall coordinate Project design with the adjacent 144th Avenue and York Street Drainage Project currently under design.  This design includes the widening of 144th Avenue from Franklin Street to York Street.
• ROW acquisition will be required with this Project.
• Consultant shall coordinate with Thornton Traffic Engineering Division to develop the best typical section for the Project budget and Scope.
• A culvert extension will be required where the German Ditch passes under 144th Avenue.  Consultant shall coordinate with Thornton and the ditch company for design approval and necessary ditch crossing agreements. 
• The Big Dry Creek culvert shall be designed to pass the ten (10) year storm event (at a minimum) as determined by the 2011 Big Dry Creek Major Drainageway Plan (developed by Urban Drainage Flood Control District), without encroachment onto the edge of asphalt.  If multiple culverts are required, weirs or offset inverts will be required such that normal dry weather flows pass through only one culvert. 
• Design of any embankment armoring needed to prevent erosion during overtopping.
• A pedestrian trail is required along the north side of 144th Avenue between the Washington Street intersection and the existing pedestrian trail from the Quail Valley subdivision near Franklin Street.  Consultant shall provide a complete design for the trail. 
• Drainage improvements and grading are required for the street widening improvements.
• A new water quality facility will be required to replace the existing wet water quality basin on the north side of 144th Avenue located just west of the Big Dry Creek crossing.
• A hydraulic analysis will be required to demonstrate a “no-rise” condition for the Base Flood Elevation, post construction, for the Big Dry Creek floodplain.
• Coordination with Thornton’s Environmental Consultant on Wetlands and 404 permitting will be required.  
  Thornton requires that the Consultant perform the following Engineering Services as it relates to the above-described Project and constitutes the basis for this Agreement. Services include, but are not limited to:
• Complete construction plans, specifications, bid plans, and package as required for construction of improvements.
• Development of eight (8) legal descriptions and revisions for ROW and easement acquisition process for four (4) parcels as defined by Thornton’s Project Manager.
• Complete ROW plans in accordance with Colorado Department of Transportation (CDOT) and Thornton’s standards.
• Coordinate with all utility companies to obtain mapping and locations, as necessary.
• Potholing and location of all utilities.
• Drainage and water quality facility design for this Project. 
• Electrical drawings and coordination required for Project streetlights.
• Engineering required for all pedestrian crosswalks, ramps, and sidewalks within Project limits.
• One (1) Public Meeting to be held during the Final Design Phase.

• Utility, stormwater, demolition, traffic control (to be recommended by proposers), signing and striping, etc., including any and all drawings required for successful advertising of this Project.The approximate design, ROW, and construction budget is four million seven hundred forty-six thousand dollars ($4,746,000).
   
  The Services shall be completed in phases as further described in EXHIBIT “A” CONSULTANT’S SCOPE OF SERVICES. 
   
  To be minimally qualified for consideration for award, proposing firms must have successfully completed three (3) projects in Colorado that have a similar degree of complexity and cost within the past five (5) years.