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STATE OF VERMONT AGENCY OF TRANSPORTATION

Scoping Report

FOR

North Hero BF 028-1(30) US ROUTE 2, BRIDGE 5 OVER ALBURGH PASSAGE

April 26, 2016

Prepared by

GREEN INTERNATIONAL AFFILIATES, INC. Civ i l and St ructura l Engineers

Scoping Report North Hero

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Table of Contents I. Site Information .................................................................................................................................... 3

Need ........................................................................................................................................................... 3 Traffic ........................................................................................................................................................ 3 Design Criteria .......................................................................................................................................... 4 Inspection Report Summary .................................................................................................................... 5 Hydraulics ................................................................................................................................................. 6 Utilities ....................................................................................................................................................... 6 Right-Of-Way ........................................................................................................................................... 6 Resources ................................................................................................................................................... 7

Biological: ............................................................................................................................................... 7 Archeological: ......................................................................................................................................... 7 Historic: .................................................................................................................................................. 7 Hazardous Materials: ............................................................................................................................. 8 Stormwater: ............................................................................................................................................. 8

II. Safety ..................................................................................................................................... 8 III. Alternatives Discussion ........................................................................................................ 8

No Action ................................................................................................................................................... 8 Rehabilitation ............................................................................................................................................ 9 Alternative 1: Deck Replacement ............................................................................................................ 9 Alternative 2: Superstructure Replacement ......................................................................................... 10 Alternative 3: New Structure ................................................................................................................. 10

IV. Maintenance of Traffic ..................................................................................................................... 12 Option 1: Off-Site Detour ...................................................................................................................... 12 Option 2: Temporary Bridge ................................................................................................................. 12 Option 3: Phased Construction ............................................................................................................. 13 Option 4: Ferry ....................................................................................................................................... 13 Option 5: Maintaining Traffic on the Existing Bridge ........................................................................ 14

V. Alternative Contracting Methods ..................................................................................... 14 VI. Alternatives Summary ....................................................................................................... 15 VII. Cost Matrix1 ....................................................................................................................... 16 VIII. Conclusion .......................................................................................................................... 17 IX. Appendices .......................................................................................................................... 18

Appendix A: Site Photos ................................................................................................................................. 19 Appendix B: Town Map ................................................................................................................................. 23 Appendix C: Bridge Inspection Report ......................................................................................................... 25 Appendix D: Preliminary Hydraulics Report .............................................................................................. 27 Appendix E: Preliminary Geotechnical Report ........................................................................................... 29 Appendix F: Natural Resources Memo ......................................................................................................... 33 Appendix G: Archeological Memo ................................................................................................................ 35 Appendix H: Historic Memo .......................................................................................................................... 39 Appendix I: Community Input ...................................................................................................................... 41 Appendix J: Traffic Research Memo ............................................................................................................ 44 Appendix K: Level of Service Analysis ......................................................................................................... 47 Appendix L: Detour Route ............................................................................................................................. 50 Appendix M: Alternative Contracting Decision Matrix .............................................................................. 52 Appendix N: Plans .......................................................................................................................................... 54

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I. Site Information Bridge 5 is a state owned bridge located on US Route 2 in the Town of North Hero, approximately 0.2 miles east of the junction with VT Route 129. The bridge carries US Route 2 over the Alburgh Passage of Lake Champlain. The existing conditions were gathered from a combination of a site visit, the Bridge Inspection Report, the Route Log and the existing survey. See correspondence in the Appendix for more detailed information. Roadway Classification Minor Arterial Bridge Type 7 Span CIP Concrete Deck on Steel Plate Girders Bridge Length 826 feet Year Built 1954 Ownership State of Vermont

Need The following is a list of deficiencies of North Hero Bridge 5 and US Route 2 in this location.

1. Bridge 5 is Structurally Deficient.

2. The existing concrete deck is in poor condition with a rating of 4 and there are several recommendations in the inspection report for replacement.

3. The existing superstructure is fracture critical.

4. Although the structure meets current roadway width requirements, local officials have expressed concerns regarding near misses with fishermen on the bridge.

5. The railing is historic and may need to be replaced to meet current standards. Traffic A traffic study of this site was performed by the Vermont Agency of Transportation. The traffic volumes are projected for the years 2017 and 2037.

TRAFFIC DATA 2017 2037

AADT 2000 2400 DHV 270 320 ADTT 200 340

%T 7.9 11.5 %D 57 57

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Design Criteria The design standards for this bridge project are the Vermont State Standards (VSS), dated October 22, 1997, AASHTOs A Policy on Geometric Design of Highways and Streets, 6th Edition (AASHTO Green Book) and the VTrans Structures Design Manual dated 2010. The minimum standards referenced in the following table are for a Two Lane Minor Arterial roadway based on an ADT of 2,400, a DHV of 320, and a design speed of 40 mph.

Design Criteria Source Existing Condition Minimum Standard Comment Approach Lane and Shoulder Widths

VSS Table 4.3 12/5 (34) 11/4 (30)

Bridge Lane and Shoulder Widths

VSS Table 4.3 11/4 (30) 11/4 (30)

Clear Zone Distance VSS Table 4.4 No issues noted 14 fill 1:4 / 12 cut 1:3, 12 cut 1:4

Banking VSS Section 4.13 e = 7% 8% (max) Speed VSS Section 4.3 40 mph (Posted) 40 mph (Design) Horizontal Alignment AASHTO Green

Book Table 3-10b R=716.8, Both curves East and West of the bridge

R=716 for e = 7% and 40 mph design speed

Vertical Grade VSS T