Enosburg BRO 1448(40)Bridge 48 on TH 2 Over the Tyler Branch

Alternatives Presentation

TH 47 BR 46

PROJECT LOCATION

Meeting Outline

• Purpose of the Meeting• Structures Section re-organization• Existing bridge deficiencies• Alternatives considered• Summary and recommendation-

Purpose of Meeting

• Present the alternatives that we have considered• Explain the constraints to the project• Help you understand our approach to the project• Provide you with the chance to ask questions.• Provide you with the chance to voice concerns• Build consensus for the recommended alternative -

Phases of Development

Project Definition Project Design Construction

Project

Funded

Project

Defined

Contract

Award

Identify resources & constraints

Evaluate alternatives

Public Participation

Build Consensus

•Quantify areas of impact

•Environmental permits

•Right-of-Way Process

•Utility Coordination

•Develop plans, estimate and specifications

Accelerated Bridge Program

• Began in January 2012• Bridges are deteriorating faster than we can fix them• Accelerated Bridge Construction (ABC) is key• Impacts to property and resources is minimized• Standard details repeated on many projects• Shift from individual projects to programmatic approach• Accelerated Project Delivery• Goal of 2 year design phase for ABP (5 years

conventional)• Goal of 25% of projects into Accelerated Bridge Program-

Project Initiation & Innovation Team

• Part of re-organization in January 2012• Currently team of 5• All projects will begin in the PIIT• Very efficient process• Look for innovative solutions whenever possible• Involved until Project Scope is defined• Hand off to PM to continue Project Design phase -

Project Background

• Priority 20 in the Town Highway Bridge Program• The structure is owned and maintained by the Town• TH 2 is a Class 2 Town Highway• Existing bridge is a single-span steel beam bridge with a

concrete deck (replaced with temporary Mabey bridge)• Span of 47 feet and width of 18 feet• The bridge was built in 1924• Bridge is structurally deficient and has a Federal

sufficiency rating of 9.0 (out of 100) -

Project Background (Cont)

• Traffic Data

2015 2035

AADT 690 740

DHV 100 110

ADTT 45 55

%T 5.8 6.9

• Design speed = 50 mph (Note: 4 way stop proposed)

Description of Terms Used

Beams (Superstructure)

Deck

Abutment (Substructure)

Bridge Rail

EXISTING BRIDGE DEFICIENCIES

Deficiencies

• The deck, superstructure and substructure are in critical to poor condition

• The bridge width does not meet the current standard.

Inspection Report Information (Based on a scale of 9)

Deck Rating 3 Critical

Superstructure Rating 4 Poor

Substructure Rating 4 Poor

Channel Rating 5 Fair

18’

Width of Bridge

Bridge Side View

Existing Site Conditions• Bridge Width (Face-Face Rail) = 18’-0”• Design Speed Limit = 50 mph (Note: 4 way stop)• No Postings for Weight Restriction• Overhead Utilities present (cross over bridge)-

Layout Showing Constraints

Proposed Project

• Complete bridge replacement warranted• Use 10’ lanes w/ 2’ shoulders (24’ rail-rail width)• Approximately 48’ span• Improved intersection w/ 4 way stop -

Alternatives

1. Full replacement w/ abutments on bedrock

Proposed Bridge Typical

Alternative 1

Alternative 1 Profile

Bridge Closure Details• 4 week closure specified in contract• Timing of closure will be made w/ input from Town

(to minimize community impacts)• Town responsible for detour route (location,

signing, installing, maintaining)• One route adds 3 miles and is 11 miles end-end• Local share cut in half w/ closure-

Alternatives Matrix Alt 1

Construction Cost $640,000

Construction w/ Construction Engineering & Contingencies $864,000

Preliminary Engineering $160,000

Right of Way $0

Total Cost $1,024,000

Town Share (5% w/ closure) $51,200

Project Development Duration 2 years

Construction Duration 3 months

Mobility Impact Duration 4 weeks

Questions