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TZB/I-287 Environmental Review TEA / TUG Conference Bridge and Transit Recommendations

TZB/I-287 Environmental Review TEA / TUG Conference Bridge and Transit Recommendations October 6, 2008. Subjects. Rehabilitate or Replace TZB Transit Mode Recommendation Next Steps Finance Process. Part 1 Rehabilitate or Replace the Bridge. Hudson River Main Channel.

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TZB/I-287 Environmental Review TEA / TUG Conference Bridge and Transit Recommendations

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  1. TZB/I-287 Environmental Review TEA / TUG Conference Bridge and Transit Recommendations October 6, 2008

  2. Subjects • Rehabilitate or Replace TZB • Transit Mode Recommendation • Next Steps • Finance • Process

  3. Part 1 Rehabilitate or Replace the Bridge

  4. Hudson River Main Channel

  5. Evaluation Criteria Discriminating Criteria Notable Criteria

  6. 5 Bridge Sections Segment 1: Causeway Segment 2: West Deck Truss Segment 3: Main Spans Segment 4: East Deck Truss Segment 5: East Trestle

  7. Rock (Sandstone) Clay Approx 700 feet to rock Organic Soils Sand Clay 200-250 feet to rock Gravel Rock (Gneiss) Subsurface Conditions

  8. Concrete pile caps (Causeway)

  9. Buoyant Foundations

  10. Overview of TZB Status • The TZB is currently safe but will not last into the future without major upgrade 9/23/2014

  11. What does ‘safe’ mean? • AASHTO Bridge Specification • Strength • Serviceability • Fatigue/Fracture • Extreme Events Complies (but with reducing factors of safety) Does not comply Complies (but with reducing factors of safety) Does not comply 9/23/2014

  12. Why is the bridge suffering? • Structure was designed ‘thin’ (thin deck, timber foundations, reduced thicknesses, open sections) • Structure was designed ‘flexible’ (200 joints opened the bridge to chloride attack) • The number of components is high (almost 100,000 pieces) 9/23/2014

  13. Overall Condition Rating Vs. Cost $500 $400 7 - New Condition Cost of Repair (Millions) 7 $300 $200 $100 6 $0 5 - Minor Deterioration 5 Inspection Rating 4 Average condition rating 3 - Serious Deterioration Deficient 3 Bi-annual condition rating 2 1 - Failure 1 1975 1980 1985 1990 1995 2000 2005 Year

  14. Causeway – Deck Deterioration Spalled Concrete (yellow) Hollow Sound (Green) Notable Radar Discontinuity (Blue) Major Radar Discontinuity (Pink)

  15. Punch-Through Failure of the Deck (Under Repair) Causeway – Deck Repair Note deck thickness 6.75 inches

  16. TZB Causeway Piers and Foundations

  17. Underneath Causeway Cracked Concrete Under Drainage Outlet at Top of Pier (Repaired)

  18. Underneath Causeway Cracked Concrete Under Drainage Outlet at Top of Pier (Repaired)

  19. Underneath Causeway Cracked Concrete at the Base of the Pier

  20. Causeway Foundations Cracking at Side of Pilecap

  21. Causeway Foundations Timber Piles Below Pilecap

  22. Why the Causeway is Replaced Extent of the concerns and modifications makes causeway replacement essential

  23. Main Spans – Maintenance Challenge Steel Corrosion (Repaired)

  24. Example Plate Connecting Horizontal, Vertical and Inclined Members (Repaired) Main Spans – Gusset Plates

  25. Main Spans – Maintenance Challenge

  26. TZB Physical Condition - Summary • TZB is in Safe Condition • Deterioration Became Significant in 1980’s • 20 Years of Major Investment to Date • Expenditure is Increasing • Cycle of Deterioration and Repair Continues

  27. Seismic Example of model used for seismic assessment of the existing TZB main spans Soil layers Movie

  28. Seismic Corner of Buoyant caisson Example of local model used to assess the extent of cracking in the existing buoyant foundations Cracking Movie

  29. Seismic - Buoyant Caisson Replacement New Transfer Structure Existing Caisson New structure

  30. Buoyant Caisson Replacement Existing Replacement

  31. Rehabilitated Main Spans 10-20% of members to be retrofitted New Structure

  32. Construction Impacts Criterion – Riverbed Disturbance Rehabilitation Option 3 (BRT) Replacement Option 2 (BRT)

  33. Construction Impacts Criterion Rehabilitation Option 2 Rehabilitation Option 3 New Structure Replacement Option 1 Rehab

  34. Construction Impacts Criterion Rehabilitation Option 3 Replacement Option 2 New Structure Replacement Option 3 Rehab Structure

  35. Rehabilitation Options Option 4 Option 2 Option 3 Option 1 Replacement Options Option 2 Option 3 Option 1 Seven TZB Options

  36. Cost Criteria (2012 dollars) $6.6 $6.3 $6.4 $6.4 $5.2 $5.1 Capital Cost (Billions) $3.4 $1.5 $1.4 $1.2 $1.1 $0.9 $0.7 $0.7 NPV 150-year Maintenance Cost (Billions) Rehabilitation Options Replacement Options

  37. Executive Steering Committee Recommendation • Replacement of TZB Recommended • Rehabilitation of existing bridge in-kind is not viable • Does not meet project purpose and need • Retains serious vulnerabilities • Rehabilitation options require extensive new work • Costs are comparable to replacement options • River impacts comparable in all options • Rehabilitation options retain serious vulnerabilities • Existing main span retained is non-redundant • Retained main span will continue to deteriorate • Replacement options have high life cycle (150 yrs)

  38. Part 2 Transit Mode Recommendation

  39. Inventory of Transit Alternatives

  40. Analysis of Transit Modes • All alternatives were subject to a rigorous analytic process • Transit ridership • Highway impacts • Travel time benefits • Capital and operating costs • Preliminary environmental impacts • Not an FTA NEW STARTS Application Analysis; yet concise • Results in Transit Mode Selection Report

  41. Best Performing Alternative • Alternative 4Dis the best performing alternative, comprised of the following components: • Regional Bus Rapid Transit network • High Occupancy Toll (HOT) lanes on bridge and highway in Rockland • Exclusive bus lanes along Route 119 and Westchester Avenue • New BRT stations (may become joint bus/rail stations) • Routes serve Orange/Rockland Counties, White Plains, I-287 Corporate Parks, Port Chester, SW CT • New two track Commuter Rail Line • Links Port Jervis Line to Hudson Line • Tunnel, at-grade and viaduct sections in Rockland County • New Rockland County stations • Underground connection to Hudson Line in Westchester

  42. Most Total Trips on New Service

  43. Delivers Highest Ridership Increase • Generates highest transit ridership (cross-corridor, to NY, total) compared to other EIS alternatives studied • Almost 40% of ridership (CRT, BRT) would be new to transit, thus diverting cars off the roadway network

  44. Diverts Most Trips from Automobiles • Alternative 4D diverts 8,400 cars in the peak period which represents about 21% of auto trips originating in Orange/Rockland and destined for Manhattan

  45. Delivers Fastest Travel Times • Delivers faster travel times to NYC than existing or currently planned (i.e. ARC) transit alternatives • As much as a 45 minute savings versus existing rail trips from eastern/central Rockland County to Manhattan’s east side • BRT saves 50 minutes on trips between Suffern and White Plains vs no-build • Highest aggregate travel time savings • 8,100 hrs/day in AM peak period vs existing rail • 4,200 hrs/day (AM peak) saved vs bus from Suffern to White Plains

  46. Total Transit Capital Cost(Year 2012 Dollars) $1.0 B for BRT (Rockland/Westchester) $6.7 B for CRT (Suffern to Hudson Line)

  47. Net Cost per Passenger Mile 3A 3B 4A 4B 4C 4D $3.00 $0.00 $1.00 $2.00 Annualized Capital + Annual OperatingCosts = Total Annual Transit Cost Net Cost per Passenger Mile = Total Annual Transit Cost – Annual Fare Revenue Total Passenger Miles Average Net Cost per Passenger Mile--4D $1.45

  48. Complements ARC Project • Provides West-of-Hudson commuters with east/west Midtown Manhattan terminal choice • Adds track capacity for Manhattan trips ARC SERVICE 30% ARC riders divert TZ SERVICE 40% ARC riders 60% New riders

  49. Air Emissions Reductions (tons in the AM peak period in 2035)

  50. Net Fuel Savings – Gallons (AM Peak Period)

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