HomeMy WebLinkAboutStaff Report 7209
City of Palo Alto (ID # 7209)
City Council Staff Report
Report Type: Action Items Meeting Date: 11/7/2016
City of Palo Alto Page 1
Summary Title: Review Adobe Creek/Highway 101 Pedestrian Overcrossing
Project Design Concept Approval
Title: Review and Potential Direction to Add Optional Enhancements and
Associated Costs for the Adobe Creek/Highway 101 Pedestrian Overcrossing
Project, Capital Improvements Program Project PE-11011
From: City Manager
Lead Department: Public Works
Recommendation
Staff recommends that Council:
1) Review the 15% design and estimated costs of optional enhancements for
the Adobe Creek/Highway 101 Pedestrian Overcrossing Project; and
2) Determine whether any optional enhancements should be added to the
project, and accordingly direct staff to amend the contract with Biggs
Cardosa Associates, Inc. and increase the budget for the Adobe
Creek/Highway 101 Pedestrian Overcrossing Project, Capital Improvements
Program (CIP) Project PE-11011.
Executive Summary
This report provides an update on the design of the baseline bridge with core
additional elements, and a review of the potential optional enhancements to the
project and their associated costs. The design team, Biggs Cardosa Associates,
(BCA) has developed a 15% design for a 12-foot wide baseline bridge, which
consists of: a bowstring steel truss principal span, concrete approaches, an
eastern approach overlook platform, western approach alternative access
(originally anticipated to be a stairway), enhanced lighting, Adobe Creek Reach
City of Palo Alto Page 2
Trail head improvements, and educational signage. The baseline bridge is
expected to meet the project’s $13 million budget. The optional enhancements
that could be added to the project by Council include an eastern approach ramp
plaza, enhanced railings and fencing, enhanced amenities, modification of
principal span and approach structures to provide a 16-foot clear width, and five
alternative principal span steel truss structure types. Staff will return to Council
with a design services contract amendment and budget adjustment in December
should optional enhancements be selected. The anticipated Google contribution
of $1 million is not yet included in the $13 million budget and could be used to
fund optional enhancements, or act as a contingency to offset any increased
project costs (such as higher than anticipated construction cost escalation), or
reduce the City’s general fund contribution of $4.65 million to the project. If
County of Santa Clara Board of Supervisors is amenable, the $4.5 million funds in
County Trail Funds relinquished by Stanford University may be an additional
source of project funding.
Background
Council approved the design contract with Biggs Cardosa Associates, Inc. (BCA) on
May 23, 2016 (Staff Report ID# 6578). The contract includes Phase 1, 65% design
development services for a bird-friendly, 12-foot wide, prefabricated bowstring,
standard steel truss bridge that spans Highway 101 with concrete approaches and
meets the $13 million total project budget. The design intent is to combine a basic
bridge with core additional elements (western stair, signage, Adobe Creek Reach
Trail, enhanced lighting and overlook), with the potential to add optional
enhancements identified during the design competition that would increase the
bridge cost beyond the $13 million budget. Council directed staff to return at the
15% design level, prior to commencing the environmental assessment, to review
the design concepts, graphics and estimated costs for optional enhancements.
Staff received positive feedback in August and September on the 15% design
bridge alignment, access and maintenance from Pedestrian and Bicycle Advisory
Committee (PABAC) and Santa Clara Valley Water District (SCVWD)
representatives.
City of Palo Alto Page 3
Discussion
Baseline and Core Additional Project Elements
The baseline bridge is a 12-foot clear width (14 feet total width), bowstring steel
truss principal span, with additional steel truss spans over East and West
Bayshore Roads, and concrete approach ramp structures. The core additional
elements include an eastern approach overlook platform, western approach
alternative access (originally anticipated to be a stairway), enhanced lighting,
Adobe Creek Reach Trail head improvements, and educational signage. The
baseline and core additional project elements are configured to meet the $10
million construction budget and $13 million total project budget. Attachment A
provides the 15% concept plans and design renderings. The core additional
elements are also described in Attachment A, and are briefly summarized below.
Eastern Approach Overlook Platform
The eastern approach overlook offers sweeping views of the Baylands and Adobe
Creek setting. The overlook provides an opportunity for additional amenities.
West Bayshore Road Improvements and new Adobe Creek Reach Trail
The bridge geometry and sidewalk bike path and roadway interface is an
opportunity to improve access for pedestrians and cyclists. Integrating the
existing sidewalk into the bridge approach ramp removes the need for a stairway
and provides cyclists with a dedicated bike lane over Adobe Creek Bridge on West
Bayshore Road.
Best practices in bikeway design support a one-way separated bikeway on each
side of West Bayshore Road. The new Adobe Creek Reach Trail will connect West
Bayshore Road to East Meadow Drive with a new west plaza and trailheads. The
new trailheads, sidewalk and bike lane details will be further developed and
presented to the community.
Enhanced Lighting
Ground-mounted and handrail lighting provides low-impact direct pathway
lighting and reduces light spilling beyond the bridge and pathways. Lighting poles
along the western approach will limit light pollution by incorporating shields to
push light away from the Barron/Adobe confluence. Interactive lighting offers an
artistic element and will be explored further. Lighting levels will dim using an
City of Palo Alto Page 4
astronomical clock to reduce light output while meeting photometric
requirements.
Optional Enhancements
Optional enhancements to the project include a plaza at the eastern approach
ramp entrance, enhanced railings and fence mesh, enhanced amenities, a 16-foot
(rather than 12-foot) span and approach width, and five alternative principal span
steel truss types. Some of the principal span truss alternatives utilize the same
truss types, with a distinction of whether the structure clear-spans only Highway
101 and uses additional spans to clear East and West Bayshore Roads, or clear-
spans Highway 101 and one or both of the frontage roads. Attachment B provides
the 15% concept plans and design renderings for the optional enhancements. The
optional enhancements are described in Attachment B, and are briefly
summarized below.
Plaza at Eastern Approach Ramp
Walkway and cyclist access to the San Francisco Bay Trail and proposed bridge is
an opportunity to create a trailhead and improved interface with the current
roadway, and bike and pedestrian paths.
Enhanced Railings and Fence Mesh
Railings integral with fencing and fence density, and patterns of mesh can avoid
impacts to wildlife while providing an aesthetic alternative.
Enhanced Amenities
Benches, interpretive signage and drinking fountains will improve user comfort
and education opportunities. Salvaged wood from the Baylands boardwalk
decking could be repurposed for benches, deck elements and informational
signage.
Structure Width Increase to 16 feet
12 feet of continuous clear width is consistent with the design guidelines in the
City of Palo Alto Bicycle + Pedestrian Transportation Plan for shared-use paths
and is greater than the minimum standard. California Department of
Transportation (Caltrans) minimum guidelines use an 8-foot minimum width
including shoulders. However, a 16-foot deck width would allow for separation of
bicyclists and pedestrians. A structure width of 16 feet is expected to be feasible
City of Palo Alto Page 5
only for the baseline bowstring truss structure type and the three other principal
span steel truss alternatives (as described below) that utilize three spans rather
than a single, longer span. For reference, the existing Highway 101 crossing at
Palo Alto’s Embarcadero pedestrian/bike bridge is 6.5 feet wide, while the
Highway 101 Mountain View bike bridge is 10 feet wide.
Principal Span Steel Truss Alternatives
Bridge spans vary in span length, width, aesthetic treatments, cost and
complexity. A three-span bridge consists of one 165-foot long prefabricated steel
structure spanning Highway 101 with two concrete or steel structure spans at
East and West Bayshore Road. A single span bridge consists of one 200-foot to
240-foot long prefabricated steel structure spanning Highway 101 and East
and/or West Bayshore Roads.
Costs of Optional Enhancements
Table 1 provides the estimated additional cost for each optional enhancement. If
Council determines that any optional enhancements should be included in the
project, the contract with BCA will require an amendment to cover the additional
design work and increase the CIP project budget. As noted in the Public and
Private Funding Possibilities section below, the anticipated Google contribution of
$1 million could be used to fund optional enhancements, act as contingency to
offset any increased project costs (such as higher than anticipated construction
cost escalation) or reduce the City’s general fund contribution to the project. A
portion of the County of Santa Clara $4.5 million recreation grant may be a
possible funding source.
City of Palo Alto Page 6
Table 1: Summary of Optional Enhancements and Additional Costs
Optional Enhancements Additional Cost*
Plaza at eastern approach ramp $0.42 million
Enhanced railings and fence mesh $0.47 million
Enhanced amenities $0.13 million
Increase span and approach widths to 16 feet $2.4-3.5 million
Truss type alternative 1: Bowstring (1 span, self-
weathering)
$2.12 million
Truss type alternative 2: Closed (3 spans, self-
weathering)
$2.9 million
Truss type alternative 3: Closed (1 span, painted) $1.93 million
Truss type alternative 4: Sloped Open (3 spans, self-
weathering)
$0.71 million
Truss type alternative 5: Inclined U-frame (3 spans,
painted)
$2.25 million
*These figures represent the total of planning-level construction estimates and
design fees, 3 years at 3% per year inflation to mid-point of construction, 10%
mobilization and a 20% contingency.
Maintenance Considerations
Painting or Galvanizing Steel
A painted or galvanized steel bridge can have a life over 50 years, but regular and
proper maintenance can typically extend the life to 75 to 100 years. Painted and
galvanized structures require periodic inspection, repair, repainting over the life
of the structure and sometimes blasting and re-coating.
Self-Weathering Steel
Self-weathering steel can have a life over 50 to 75 years. The chemical
composition of the steel eliminates the need for painting as the steel forms a
protective layer on its surface under the influence of the weather. However, the
regular and prolonged exposure to moist environments, such as regular coastal
fogs and wetlands can negatively affect the life as the protective layer may not
stabilize but instead continue to corrode. The bridge span over Highway 101
combined with wind is in a relatively dry environment and is not a significant
concern.
City of Palo Alto Page 7
Project Coordination
The City’s Public Art Program is currently compiling a pool of prequalified artists
with previous experience working on similar transportation projects. After
completing a selection process and early in the bridge design phase, the City plans
to have the artist join the design team to identify opportunities to incorporate
artwork in the design. Due to the limited budget, the design team will work with
the artist to leverage existing budgeted bridge design elements to maximize the
impact of the artwork.
Coordination with Pacific Gas and Electric (PG&E) and with SCVWD will ensure the
approach structures do not compromise existing utility and creek access. The
touchdown on the west side of the Adobe/Barron Creek channel and the new
Adobe Creek Reach Trail requires coordination and approval from SCVWD. A Joint
Use Agreement with SCVWD will be negotiated before final design begins and
finalized before the undercrossing closes permanently when construction begins.
Caltrans coordination is underway with a November project team meeting to
share the 15% design and geotechnical soil boring program information. A
Cooperative Agreement with Caltrans will be required before construction begins.
Staff will return to the community, boards, commissions, PABAC, SCVWD, Caltrans
and private/public utilities during the design phase once Council directs staff on
the optional enhancements.
Public and Private Funding Possibilities
County/Stanford Trails Funds
Stanford University and the City submitted a joint $8.5 million grant application in
2012 and Stanford was awarded $4.5 million from the Santa Clara County
Recreation Fund established by the County/Stanford Trails Agreement. Since that
time Stanford University has relinquished the $4.5 million grant funding and built
the Stanford Perimeter Trail with its own funds. If the county is amenable, the
relinquished $4.5 million in grant funds could be allocated to the project.
Currently, County of Santa Clara staff asked City staff to refrain from making a
formal request while internal discussions are occurring. Any use of the funds is
subject to the approval of the Santa Clara County Board of Supervisors.
City of Palo Alto Page 8
Google Contribution
A contribution of $1 million from Google is planned to supplement the current
$13 million project budget or to offset the City’s current funding allocation. If the
Google contribution is used to supplement the current $13 million budget, it
could be used to fund optional enhancements at Council’s direction, or could be
maintained as a contingency fund to offset any increases in project costs.
OBAG Cycle 2 Funds
Staff anticipates approval of the request for $4.35 million in OBAG Cycle 2
construction funds pending Santa Clara Valley Transportation Authority’s
selection process this fall. The OBAG funds could not be coupled with BEP funds
for Category 1 projects described below.
Bicycle Expenditure Program (BEP) and Future County Sales Tax Funds
The 2040 Valley Transportation Plan (VTP) and the Santa Clara Valley
Transportation Authority Bicycle Expenditure Plan identify the $9.5 million
overcrossing project for Category 1, BEP funds. The project also appears in the
draft list of bicycle and pedestrian projects that may be eligible for future county
sales tax funding. The unpredictability in sales tax revenue makes planning for
long‐term future funds uncertain.
Resource Impact
Funding for this project is included in Capital Improvement Program (CIP) project
(PE-11011) - Highway 101 Pedestrian/Bicycle Overpass Project. If Council directs
staff to add any optional enhancements, the project budget will need to be
increased.
The current project funding is as follows:
Funding Source Funding Amount
Santa Clara County Recreation Fund $4.0 million
OBAG Cycle 2* $4.35 million
General Fund $4.65 million
Sum: $13.0 million
City of Palo Alto Page 9
*Approval of the OBAG Cycle 2 funds, which replace Surface Transportation
Improvement Program (STIP) funds deleted by the California Transportation
Commission due to a funding shortfall, is expected in fall 2016.
Policy Implications
The project is consistent with the Comprehensive Plan goals, policies and
programs.
Goal T-3: Facilities, services and programs that encourage and promote
walking and bicycling.
Goal T-14: Improve pedestrian and bicycle access to and between local
destinations, including public facilities, schools, parks, open
space, employment districts, shopping centers, and multi-
model transit stations.
Policy T-25: When constructing or modifying roadways, plan for usage of
the roadway space by all users, including motor vehicles,
transit vehicles, bicyclists, and pedestrians.
Timeline
Schedule and milestones:
Phase 1:
Begin environmental assessment and 35% design – November 2016
Potential BCA contract amendment for optional enhancements
based on Council direction – December 2016
Complete 35% design and public review meeting – Fall 2017
Complete environmental assessment – Winter 2017
Complete 65% design – Winter 2017
Phase 2:
Authorize Phase 2 and Phase 3 services – Fall 2017
OBAG Cycle 2 access to funding – October 2018
Phase 3:
Begin construction, construction administration – early 2019
Complete construction – early spring 2020
City of Palo Alto Page 10
Environmental Review
Selection of the optional enhancements does not constitute approval of the
project. Pursuant to the California Environmental Quality Act (CEQA), a draft
Mitigated Negative Declaration analyzing the proposed project, including the
selected optional enhancements, will be prepared for public review and for
consideration by advisory and decision-making bodies prior to project approval.
Because the project may include federal funding, the City will file for a categorical
exclusion under the National Environmental Policy Act (NEPA).
Attachments:
Attachment A: 15% Project Concept Plan and Graphics (PDF)
Attachment B: Optional Enhancements Conceptual Renderings (PDF)
City of Palo Alto
15% PS&E Concept Plan and Graphics
Baseline + Core Additional Elements
PATTACHMENT A
Eastern Approach
Overlook
PRINCIPAL SPAN
STRUCTURE
Enhanced Pathway Lighting
Informational /
Educational
Signage
Alternative Principal Span Study
Structure Clear Width Study
Enhanced Railing Design
Enhanced
Amenities
Package
Western Approach
Access
WESTERN APPROACH
STRUCTURE
PROJECT PLAN VIEW
BASELINE + CORE + OPTIONAL ENHANCEMENTS
Eastern Plaza
EASTERN APPROACH
STRUCTURE
West Bayshore Rd
Improvements
Adobe Creek
Reach Trail
Trailhead at W. Bayshore Road
CORE
LEGEND:
OPTION
N
PRINCIPAL SPAN
STRUCTURE EASTERN APPROACH
STRUCTURE
WESTERN APPROACH
STRUCTURE
PROJECT OVERVIEW
LOOKING NORTH
N
EASTERN APPROACH OVERLOOK
This overlook will provide users the opportunity to pause, rest, view and appreciate the adjacent Baylands Nature Preserve. The architecture of the overlook
will compliment the main bridge structure elements, including railings and concrete facing textures and colors.
The overlook will be decked with a wood finish to make the area more distinguishable from the main pathway and to give it some warmth in texture and
color. The decking and the bench elements could be constructed from recycled and repurposed existing timber decking from the adjacent Baylands
Boardwalk Project.
Amenities such as benches and informational/educational signage will also be located on the overlook to further enhance the experience for the users.
WESTERN APPROACH ACCESS
An access structure will be incorporated into the baseline Western Approach Structure.
For northbound pedestrians along West Bayshore Road, the access structure can
reduce the length of travel by roughly 500 feet.
Three initial alternatives were considered: 1) Access Stair Option 1: Located near the
interface of the Principal Span and Western Approach Structure; 2) Access Stair Option
2: Located lower along the path where the overcrossing structure becomes supported
on fill; and 3) Access Ramp/Raised Sidewalk: Located between the existing parking lot
and the Adobe Creek Bridge.
The access ramp/raised sidewalk alternative is preferable since it creates equal access
to mobility impaired trail users and it provides a pedestrian bypass allowing the existing
bike lane along West Bayshore Road to be made continuous across the existing Adobe
Creek Bridge. It also provides a functional ADA compliant alternative access which can
be used as primary ingress/egress if and when the SCVWD closes the trail access area
for their channel sedimentation maintenance.
Access Ramp/Raised Sidewalk
(Looking SE)
WEST BAYSHORE ROAD IMPROVEMENTS
Currently the existing bicycle lane drops off at the Adobe Creek Bridge
at West Bayshore Road and the bike lane and sidewalk merge into an
approximately 5-foot wide single raised shared sidewalk. A feasible
and economical means to accommodate a separate bicycle and
pedestrian facility at West Bayshore Road at Adobe Creek was
investigated.
We reviewed widening the existing roadway structure to accommodate
the bicyclists and pedestrians but the multiple utilities carried by the
existing structure are problematic and would require considerable
retrofit of the existing structure. Based on conversations with the
SCVWD, it was preferable to limit the amount of intrusion into the creek
from both the bridge structure and its associated retaining structures.
The access ramp/raised sidewalk alternative allowed us the opportunity
to essentially accomplish the desired goal with one element.
Access Stair
Option 1
Access Stair
Option 2
Access Ramp/Raised
Sidewalk (Baseline)
WEST APPROACH
STRUCTURE
PRINCIPAL SPAN
Demolish Exist Sidewalk
for Bike Lane
City of Palo Alto
Enhanced Lighting
LIGHTING DESIGN CONCEPT
Lighting design will be provided for the pedestrian overcrossing at Adobe Creek that
contributes to the project goals of providing connectivity while addressing
environmental concerns. Paths are to be illuminated during night hours to support
pedestrian and bicycling activities, with lighting levels reflecting the transition from
higher illuminated urban areas on the western side to the lower lighting of the
Baylands to the east.
The Western Approach will require higher lighting levels for better uniformity ratios to
the surrounding environment. Pole mounted luminaires provide uniform illumination
along the pathway and at landscaping leading to the Overcrossing. Lighting poles
with full cutoff above the 90° plane and no back lighting will be used in order to
limiting light pollution as well as light trespass along adjacent river.
As the pathway approaches the Principal Span, lighting is to be integrated into the
railing where possible to create a consistently illuminated pathway. Vertical
placement will allow for more forward throw, pushing the lighting further towards the
center of the pathway. Direct view of any light source is to be shielded from adjacent
vehicular vantage points to reduce glare and distraction for drivers.
This type of installation would be located at key points at the Overcrossing focusing
on the user experience from the pathway in order to minimize visibility from vehicular
and the Baylands.
White luminaires, along with additional levels of lighting controls, allow the lighting
color and output to transform in response to environmental changes or pedestrian
and bicycle activity creating a reactive or interactive public art experience.
Lighting at the Eastern Approach and overlook is to be integrated into
urban infrastructure such as railings and benches. Illumination levels
should be minimal in order to reduce environmental impact on the
Baylands Nature Preserve. Lighting elements will be lowered in elevation
and light output.
Steplights will be integrated into railings where possible, providing low
levels of functional lighting along the pathway to meet photometric
requirements while minimizing environmental impact. Ground mounted
marker lights will also be used to define the edge of the overlook curb while
providing additional lighting at the pathway. Warm color temperatures
will be used to reduce impact to migratory birds and other wildlife.
Lighting controls will be utilized to reduce light output during hours with
limited activity. Light levels dim down on a set time schedule synced
with the astronomical clock. As people approach, sensors detect their
presence, allowing the lighting to change in response to pedestrian and
bicycle activity.
LIGHTING DESIGN CONCEPT
WESTERN APPROACH
AERIAL
VIEW
I LIGHTSWITCH®
WESTERN APPROACH
DAYTIME VIEW NIGHTTIME VIEW
NTS
PRINCIPAL SPAN
DAYTIME VIEW NIGHTTIME VIEW
NTS
EASTERN APPROACH
DAYTIME VIEW NIGHTTIME VIEW
NTS
City of Palo Alto
Adobe Creek Reach Trail
Highway 101 Multi-Use Path Overcrossing
Palo Alto, California PJ315 Palo Alto Highway 101 POC 2016 09-28.indd
September 30, 2016
WEST PLAZA 0 5’10’20’
TREE TO BE REMOVED
ADOBE CREEK REACH TRAIL LOOKING NORTH
TRAILHEAD LOOKING SOUTH
LOCA Tl ON MAP
NO SCALE
ADOBE CREEK REACH TRAIL
PALO AL TO, CA
INDEX OF DRAWINGS
DR AWING NO. SHEET
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DESCRIPTION
TITLE SHEET
LAYOUT PLAN
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12-131 12/19/14 PROJECT NO. DATE
Adobe Creek
Reach Trail
15% Design
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Adobe Creek
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15% Design
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15% Design
Layout Plan
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City of Palo Alto
Optional Enhancements
ATTACHMENT B
City of Palo Alto
Alternative Principal Span Study
Baseline Option 1 Option 2 Option 3 Option 4 Option 5
Principal Span Type
Prefabricated Steel Bowstring Pratt Truss X X
Prefabricated Steel Closed Box Truss X X
Prefabricated Steel Open Warren Truss X
Prefabricated Steel Inclined Warren Truss X
Principal Span Length
3 Span (60' / 165' / 70')X X X X
1 Span (240')X X
Principal Span Width
12' Clear X X X X
Varies (12' Min / 14' Max)X X
Principal Span Finish
Self Weathering Steel X X
Painted Steel X X X X
Cast-in-Place Concrete Side Spans X
Principal Span Advantages / Disadvantages
Low Profile Structure (Top of Deck to Soffit) Which Keeps Approach Structure Length to
a Minimum X X X X X X
Open Structure Type Provides High Visibility to Trail Users Contributing to Public Safety
and Discourages Graffiti X X X X X X
Prefabricated Superstructure Eliminates the Need for Falsework over Highway 101 X X X X X X
Prefabricated Superstructure Eliminates the Need for Falsework over Bayshore Rd X X X X X
Sructure Clear Spans Highway 101
(No Foundation Work Required in Hwy 101 Median)X X X X
Structure Clear Spans Highway 101 and East and West Bayshore Road
(No Foundation Work Required in Hwy 101 or Hwy 101/Bayshore Rd Medians)X X
Structural Form Provides a Unique Aesthetic to the Bay Area and Provides Visual
Interest to both the Trail Users and Traveling Public X X X
Top of Principal Span Structure is Located Below the Top of Tree Canopy Height
(Roughly 35 feet or Less Above Highway 101)X X X X
Structural System can Support Widening the Pathway to 16 foot Clear Width
(16' Clear Width Allows Separation of Bicyclists and Pedestrians)X X X X
Truss Elements are Inclined Away from the Pathway Providing Architectural Interest
and a Wider Functional Pathway for Trail Users X
Fabrication Facilities are Readily Available to Prefabricate the Principal Span Elements
(Several Prefabricators can Product this Structure Type and Span Length)X X
Span Length or Superstructure Complexity will Likely Require Fabrication at a Specialty
Fabrication Facility X X X X
Significant and/or Complicated Field Splicing will be Required to Transport due to the
Height, Width or Complexity of the Main Span Structure X X X
Description
ALTERNATIVE PRINCIPAL SPAN STUDY
STRUCTURE FEATURES AND ADVANTAGES / DISADVANTAGES COMPARISON
70’
(BASELINE)BASELINE: PREFAB BOWSTRING TRUSS (THREE SPANS)
ARCHITECTS
MESH
SCALE: 1"= 40'-0"
r HANiRAIL
H
SECTION A-A SCALE: 1•= 10'-o•
18
1 . PREFAB BOWSTRING TRUSS (ONE SPAN)
ARCHITECTS
.. -_;:·: .... -~-----.. ..
SCALE: 1"= 40'-0"
'MIN
70
2 . STEEL CLOSED TRUSS (THREE SPANS)
ARCHIT ECTS
--------
SCA E: 1"= 40'-0"
--
18' MAX 18' MAX 18' MAX
3 . STEEL CLOSED TRUSS (ONE SPAN) : I
ARCHITECTS
EXAMPLES
'
CALE: 1"= 40'-0"
·-----
SLOPED OPEN TRUSS (THREE SPANS)
15
70’
10
4
70
5 . INCLINED U-F'RAMED TRUSS (THREE SPANS) : I
ARCHIT ECTS
SECTION A-A
City of Palo Alto
Structure Clear Width Study
NOTES:
1. Typical baseline ramp structure shown.
2. Widened cross section not suitable for all principal
span study options based on difficulties associated with
transportation and on-site fabrication.
3. Widened cross section will impact SCVWD
maintenance and debris removal operations at
Adobe/Barron Creeks.
4. West approach structure cross section must be
tapered to 12' max clear at trailhead to avoid impacts to
the existing SCVWD maintenance ramp.
5. The widening of the path may not be able to be
accommodated through the entire length for certain
options. The cost impacts for this alternative will vary
from approximately $2,000,000 to $3,000,000.
City of Palo Alto
Eastern Plaza
Highway 101 Multi-Use Path Overcrossing
Palo Alto, California PJ315 Palo Alto Highway 101 POC 2016 09-28.indd
September 30, 2016
EAST PLAZA 0 5’10’20’
Highway 101 Multi-Use Path Overcrossing
Palo Alto, California PJ315 Palo Alto Highway 101 POC 2016 09-28.indd
September 30, 2016
CHARACTER IMAGES
Planting Bands
Drinking Fountain/Bottle Filler
Public Art at Trailhead Concrete Seatwall and Railing
Decorative Concrete Bay Restoration PlantingBoardwalk Pavement
Bike Racks Interpretive SignageTrash/Recycling Receptacles
City of Palo Alto
Enhanced Railing Design
BASELINE: TOP MOUTED GALVANIZED POST
WITH METAL CHAIN LINK
RAILING ENLARGED VIEW EAST APPROACH
CHAIN LINK
HANDRAI
-----
ARCHITECTS
WEST APPROACH
ENHANCED RAILING OPTIONS
OPTION 1: 2 X 4 METAL MESH INFILL RAILING
MESH
E MEMBERS
OPTION 2: CABLE RAILING
....._
OPTION 3: DECORATIVE MESH INFILL RAILING
I'-.
OPTION 4: 2 X 2 METAL MESH INFILL RAt~G
ARCHITECTS