colorado street bridge suicide mitigation … · • the open spandrel arch design with nine...
TRANSCRIPT
1
COMPREHENSIVE PARNASSUS HEIGHTS PLANMARCH 12, 2018
COLORADO STREET BRIDGESUICIDE MITIGATION ENHANCEMENTS DONALD MACDONALD ARCHITECTS + GPA + BIGGS CARDOSA
COMMUNITY OUTREACH MEETING – SEPTEMBER 26, 2019
AGENDA
donald macdonald architects
Team Introductions 30 min
Project Overview
Guiding Principals
Breakout Session: 30 min
• Environmental / Historical Elements
• Vertical Barrier Mitigation Strategies
• Aesthetics
Community Comment / Q&A 30 min
• Golden Gate Bridge Suicide Deterrent, San Francisco, California
• Ironworkers Bridge, Vancouver, British Columbia
• Cooper River Bridge, Charleston, South Carolina
INTRODUCTIONS:
DONALD MACDONALD ARCHITECTS TEAM
Suicide Deterrent Projects:
Bridge Architects
Project Overview
Case Study: Precedent Studies
• Informs Colorado Street Bridge Project with Lessons Learned
• Comprehensive Design Research and Analysis
donald macdonald architects
Golden Gate Bridge Suicide Deterrent and Wind Retrofit Project
Looked at existing suicide deterrents around the world
Comprehensive Literature Review
Case Study: Precedent Studies
donald macdonald architects
Golden Gate Bridge Suicide Deterrent and Wind Retrofit Project
Case Study: Precedent Studies
donald macdonald architects
Golden Gate Bridge Suicide Deterrent and Wind Retrofit Project
PROJECT OVERVIEW• Task Force Research / Mitigation
Alternative Intervention Proposals
Full Length Vertical Barrier
• Historic Precedent
• Architectural Vulnerabilities• Alcoves• Pilasters and Balustrade• Ends / Approaches
• Operations, Maintenance and First Responder Impacts
Key Project Meetings
Key Project Milestones
Environmental Clearance
PROJECT OBJECTIVES: DESIGN AN EFFECTIVE BARRIER/DETERRENT, IN CONFORMANCE WITH THE SECRETARY OF THE INTERIOR’S STANDARDS FOR THE TREATMENT OF HISTORIC PROPERTIES, AESTHETICALLY COMPLIMENTARY TO THE EXISTING BRIDGE.
donald macdonald architects
EXISTING STRUCTURESuperstructure replaced during 1990’s Seismic Retrofit
All structural components we will be attaching to are “new”.
ENGINEERINGEXISTING CONDITIONS ASSESSMENT
donald macdonald architects
Replace Cap Re-Use Existing Connection Plate
Deep Cores
Engineering ApproachesCONNECTION CONCEPTS
Design Approaches
donald macdonald architects
Alcoves and Pilasters
CONSTRUCTION CHRONOLOGY
• Listed in the NRHP in 1981 under Criteria A and C with a period of significance of 1913. • Criterion A: it represents Pasadena’s “economic and physical need for facilitating automobile traffic
across the Arroyo.”
• Criterion C: it is a “transitional structure in design, combining modern scale with period finish and detail.”
COLORADO STREET BRIDGE: NATIONAL REGISTER OF HISTORIC PLACES SIGNIFICANCE
CHARACTER-DEFINING FEATURES• The overall massing, proportion, and neo-classical design of the
bridge• The curved alignment of the bridge• The board-form finished, reinforced concrete design• The open spandrel arch design with nine parabolic arches (six spans
of 113 feet, two spans of 151.5 feet, and one span of 223)• The continuous arch ribs of each parabolic arch• The spandrel columns and spandrel walls that are carried by the
arch ribs • The decorative bases and capitals of the spandrel columns• The piers that form the terminus of each parabolic arch• Six smaller, arched spans with girders, that form the termini of the
bridge• Detailing on the spandrel walls at the ends of the bridge• The length (1,467.5 feet) and height (148.5 feet) of the bridge• The cross girders that tie the arch ribs together• The cantilever supported by “small arches,” but the arches are better
described as brackets• Sidewalk refuge bays with U-shaped benches above each pier• Square piers that flank the refuge bays and support the light fixtures
Standards for Rehabilitation – U.S. Secretaryof the Interior’s Standards and Guidelines for Archeologyand Historic Preservation (36 CFR 61)
National Historic Preservation Act,Section 106—Evaluation ProcessRequired with Federal Funding – Same Standards Apply
Fundamental Principals
REHABILITATION IS DEFINED AS THE ACT OR PROCESS OF MAKING POSSIBLE A COMPATIBLE USE FOR A PROPERTY THROUGH REPAIR, ALTERATIONS, AND ADDITIONS WHILE PRESERVING THOSE PORTIONS OR FEATURES WHICH CONVEY ITS HISTORICAL, CULTURAL, OR ARCHITECTURAL VALUES.
THE REHABILITATION STANDARDS ACKNOWLEDGE THE NEED TO ALTER OR ADD TO A HISTORIC BUILDING TO MEET CONTINUING OR NEW USES WHILE RETAINING THE BUILDING’S HISTORIC CHARACTER.
Mental Health Professionals
Resource Agencies
Emergency Service Providers
Historical Organizations
ENVIRONMENTAL PROCESS
The project is being designed to avoid significant impacts and is expected to fall under aCategorical Exemption or Statutory Exemption under CEQA:
• Class 1 Exemption 15301. Existing Facilities.The project involves negligible or no expansion of the use of the existing facility.
• Class 31 Exemption 15331. Historical Resource Restoration/Rehabilitation.
The project is consistent with the Secretary of the Interior’s Standards for the Treatment of Historic Properties with Guidelines for Preserving, Rehabilitating, Restoring, and Reconstructing Historic Buildings.
• Statutory Exemption 15269. Emergency Projects.The project is necessary to prevent or mitigate an emergency.
Design Approach
donald macdonal
donald macdonald architects
Effectiveness - Issues Related to: Barrier height and shape,
Eliminating toe holds and other means of climbing,
Sealing off the bridge ends
First responder's ability to communicate and access jumpers breaching portions of the barrier
Other Active and passive measures
donald macdonald architects
Historic and Character Defining Features - Issues Related to: Sensitivity to preserving the existing balustrade,
fencing, and keeping the alcoves accessible Sensitivity to modifying the light pilasters and poles
(heights) Environmental concerns the group has that this
project will impact.
donald macdonald architects
Bridge Aesthetics - Issues Related to Sensitivity to particular views of the
bridge, (specific viewpoints: residential areas, arroyo, freeways, etc.)
Sensitivity of views from the bridge, drivers and pedestrians
Discuss integrating current design with the beaux-arts architecture (proportions, massing solids and voids)
donald macdonald architects
Effective Vertical Barrier Strategies
Historic / Environmental Process
Aesthetic Design Considerations
BREAKOUT STATIONS:
Breakout Discussion
Q&A
Upcoming Public Meetings