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Johnson Street Bridge Condition Assessment
Preliminary Findings – Additional Information
April 23, 2009
1. Review preliminary findings based on April 2nd presentation
2. Clarify assumptions of Condition Assessment Overview
3. Seek approval in-principle for rehabilitation or replacement
4. Other Considerations
5. Moving project towards “Shovel-Ready”
6. Next Steps
Overview
Condition Assessment Overview
• Upgrades required for bridge components:– Structural [excluding seismic]– Mechanical– Electrical
• Bridge is safe!
• Significant condition issues – rehabilitation required immediately otherwise condition will continue to deteriorate
• Rehabilitation in future may not be an option if major work not done soon
Seismic Vulnerability
• Victoria located in most earthquake prone zone in Canada
• Bridge not designed to any seismic standards
• Seismic upgrading necessary for:– Infrastructure investment protection; and– Public safety [post-disaster design of Magnitude
8.6]
Rehabilitation Strategy
• “Order of Magnitude” cost approximately $25M - $30M [not for budget purposes]– Extends bridge life about 40 years– Preliminary estimate only. Not based on detailed
engineering design information• Geotechnical review required• Detail on pier foundation condition to be
confirmed [i.e., submerged timber piles]• May be other unknowns once work commences• Cost may rise significantly [e.g., 4th Street Bridge
experience in San Francisco]
Existing Bridge Cross-Section [m][looking west]
2.5 3.12.59.0
3-lanes
sid
ew
alk
trail rail
~ 22.3 [outside width]
~ 17.1 [deck width]
I I
Note: Not To Scale [NTS]
Requested Information on 4th Street Bridge San Francisco
• 2-lane, single-leaf bascule bridge designed by Joseph Strauss; built in 1917; historic; no rail; carries vehicular, cyclist and pedestrian traffic
• Scope, Schedule and Budget:– Major seismic retrofit, rehabilitation [i.e., mechanical, electrical,
overhead power and control systems] and to add light rail tracks
– Scheduled for 18 months; started 2003, completed in 2006
– Original estimate of $17M; final estimated cost between $34M - $55M [contractor versus city]
• Currently in litigation due to delays and claim of at least $17M budget over-run
4th Street Bridge, San Francisco cont’d
• Challenges Encountered:– Geotechnical / foundation / counterweight issues– High-pressure water line had to be relocated
unexpectedly, but buried under ~5 m of mud
Before After
Note: Photos from City and County of San Francisco website
Replacement Strategy for Comparison Purposes
• “Order of Magnitude” cost about $35M - $40M – 100-year design life– Preliminary estimate only. Not for budget purposes. Not based
on detailed engineering design information
• Includes on-street commuter bike lanes, but not enhanced multi-use trail
• Nominal work on approach roads to tie into bridge• Underground works to be reviewed• Standard engineering designed bridge, not “iconic”• Cost will increase with additional elements or features
[e.g., architecturally-significant bridge; wider cross-section, approach road reconfiguration, etc.]
Replacement Strategy for Comparison Purposes cont’d
• Need geotechnical information in harbour and along shoreline
• Need to investigate soil contamination issues
• Need to consider archaeological issues
• Does not include upgraded approaches to the bridge [i.e., east and west approaches / bridgehead area]
Typical Cross-Section Replacement Bridge [m]
2.5 5.61.89.0
3-lanes
sid
ew
alk trail & rail
~ 20.7
I I
Note: Not To Scale [NTS]
bik
e la
ne
1.8
bik
e la
ne
Heritage Assessment – Existing Bridge
• High social historical value
• High value as an engineering landmark
• High contextual value
• High overall heritage value
• Gateway to Downtown area
Social Historical Value[Bridge Opening Day, January 11, 1924 - Photos courtesy of City of Victoria Archives]
Looking east at Johnson / Wharf intersection
Looking east at Johnson / Wharf intersection
Looking east at Johnson / Wharf intersection
Looking west along Esquimalt Road
Heritage Value After Rehabilitation
• Heritage value impacted by rehabilitation work
• Still deemed to be acceptable by Heritage Consultant [Commonwealth]
View of Existing Structure With Laced
Diagonal Bracing
View of Rehabilitated Structure With
Plated Diagonal Bracing
Rehabilitation – Laced Beams
Embodied Energy and Life Cycle Assessment
• Rehabilitation: 8.4 M megajoules [over 40 years]1
• Replacement: 8.3 M megajoules [prorated over 40 years] 2
• If completed in 24 months, full closures may be required and Embodied Energy for Replacement Option will likely exceed Rehabilitation Option
• Completing rehabilitation work on bridge without closures could add a year, thus increasing Embodied Energy
[1] Does NOT include original bridge. Assumes temporary closures.
[2] Based on staged construction over 48-months to minimize full closures.
Life Cycle Costing [100 years][preliminary estimates]
• Notes: 100 year comparison; does not include Discount Rate to simplify comparison; NOT for budgeting purposes, discusson only; other details required
ScenarioInitial
Cost [$M]Future
Costs [$M] Total [$M]
1
Rehabilitate with Seismic Upgrade and Replacement in Year 40
$30 $56 $86
2Replace and Maintain to Year 100
$40 $20 $60
Other ConsiderationsRehabilitation v. Replacement
• Safety
• Support of Alternative Transportation
• Accessibility
• Environmental
• Approach Road / Bridgehead Reconfiguration
Safety
Rehabilitation• Limited cross-section, some widening
possible but extremely challenging and expensive [added cost]
• Retains s-curve [not desirable]• No on-road bike lanes• Substandard trail width on rail bridge
[no separation to rail]• City owns liability of trail on rail bridge
due to substandard width / separation• Conflict point between E&N Rail and
Galloping Goose Trail [GGRT] users
Replacement• Flexibility in design elements
• Includes on-road bike lanes
• Eliminates conflict point between E&N Rail and trail users
• Can eliminate s-curve [added cost]
• Ability to widen current GGRT to 5 m along bridge [added cost], which will eliminate liability of existing trail on bridge
• Improved safety to accommodate Trail users across bridge into Downtown
Alternative Transportation
• 30,000 vehicles per day across bridge, in addition to pedestrians, cyclists, transit and a commuter train
• CRD Regional Growth Strategy:– TravelChoices Study defined mode-share targets for
Region to be achieved by 2026:• Pedestrian mode share of 15%• Cycling mode share of 5%• Transit mode share of 10%
• Intended to help reduce SOV dependency and improve triple-bottom line [i.e., less GHG, improved quality of life and economic vitality]
Alternative Transportation – Convergence of Regional Multi-Use Trails
Lochside Trail
GallopingGoose Trail
Proposed E&N Trail
Johnson Street Bridge
Alternative Transportation cont’d
Rehabilitation• No on-road commuter bike lanes on
bridge• Retains existing multi-use trail width
of ~2-2.5 m• Linkage to future Harbour Pathway
and E&N Rail Trail• Provides limited pedestrian / cyclist
linkage to Downtown area
Replacement• Provision of on-road bike lanes to
Downtown
• Can accommodate wider multi-use trail [added cost]
• Enhances livable community objectives [e.g., Dockside, Roundhouse, Railyards, etc.]
• Enhances local and regional transportation objectives
• Linkage to future Harbour Pathway and E&N Rail Trail
Accessibility
Rehabilitation• Bridge built in 1924• Not built to today’s
accessibility standards• Surface treatment of trail
should meet ADAAG barrier-free design standards [width, obstacles, maintenance]
Replacement• Will meet current standards
for accessibility [ADAAG] and barrier-free standards
• Could expand sidewalk & Trail to enhance standard [added cost]
Note: ADAAG = American Disability Association Accessibility Guidelines
Environmental[Estimated Embodied Energy over 100 yrs]
Rehabilitation + Replace8.4 M mj [40 yrs]
9.8 M mj [replacement
prorated 60 yrs]
Notes: mj = megajoules1. Existing bridge not included in calculation2. Based on 48-month staged construction
Replacement7.3 M mj [100 yrs]
5.4 M mj [road & rail reconfiguration]
12.7 M mj [100 yrs] 218.2 M mj [100 yrs] 1
Approach Road / Bridgehead
Rehabilitation• Retains existing approach
road configuration• Reconfiguration may be
possible on east side only, but challenging and expensive [added cost]
Replacement• Opportunity to consider
reconfiguration of approaches [added cost] to rationalize road network movements and possibly create surplus lands
• Requires detailed review and traffic modelling work
Working Towards “Shovel-Ready”
• Still awaiting federal Infrastructure Grant announcement. “Shovel-ready” yet to be defined
• City approach to “shovel-ready”:– Create Johnson Street Bridge Project Team [inter-departmental]– Retain Owner’s Representative / Engineer and Communications
Coordinator– Review underground utility [public & private]– Initiate Permitting Process [CEAA, Transport Canada, First
Nations, Archaeological review, DFO, GVHA]– Initiate preliminary geotechnical investigation [foundation and
contamination]– Develop Communication Strategy and Plan
Next Steps
• Receive approval-in-principle of preferred option• Confirm scope of work [e.g., bridge width, length, approach roads]• Engage affected stakeholders• Develop preliminary and detailed design drawings; delivery method• Refine costs, schedule and details• Review Traffic Management Plan• Report back to Council with refined costs and design• Develop Communications Plan• Review funding opportunities• Prepare application for “shovel-ready” project• Prepare Borrowing Bylaw based on preferred option and refined
cost estimates
Project Team
• Project Manager: City of Victoria– Mike Lai, Asst. Director of Engineering
Transportation & Parking Services
• Prime Consultant: Delcan– Mark Mulvihill, Vice President
Infrastructure– Hugh Hawk, Technical Director
Bridge, Structures & Marine Works
• Heritage Consultant: Commonwealth– Harold Kalman, Principal
Commonwealth Historic Resource Management Ltd.