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O D O T B R I D G E D E S I G N & D R A F T I N G M A N U A L R E V I S I O N R E Q U E S T
TECHNICAL SERVICES
Bridge Engineering Section Office Phone: (503) 986-4200 Fax Number: (503) 986-3407
DATE: April 10, 2017 TO: Alex Lim
Bridge Design Standards Engineer
FROM: Alex Lim Phone: 503-986-3402 Bridge Design Standards Engineer
ODOT SUBJECT: Proposed Revision to Bridge Design & Drafting Manual RE: BDDM Section 1.16 – ADA Compliance for Bridge Work Problem Statement: Provide guidance on the ADA application to the unique situations created by bridge rehabilitation and maintenance projects. Proposal: Add Section 1.16 as follows:
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Americans with Disabilities Act Compliance for Bridge Projects The Americans with Disabilities Act of 1990 (ADA) prohibits discrimination and ensures equal
opportunity for persons with disabilities in employment, state and local government services, public
accommodations, commercial facilities, and transportation. Implementation guidelines, standards, and
court decisions provide guidance on how to comply with the law.
Although these sources are applied to transportation construction and maintenance decisions, there is
limited guidance about specific work activities on bridges. This document provides guidance on the ADA
application to the unique situations created by bridge rehabilitation and maintenance projects.
GENERALGUIDANCEThe ADA regulation prohibits discrimination against people with disabilities by government entities.
Government entities must make services accessible and usable to all people, including people with
disabilities. For the purpose of this document, the sidewalk of a bridge is a service that, if provided, must
be accessible and usable by people with disabilities, regardless of whether the bridge is in an urban or
rural setting. The Oregon Department of Transportation (ODOT) has an obligation to ensure that a
bridge sidewalk is accessible and usable. ODOT addresses that obligation in several ways. Through the
ADA Transition Plan, all pedestrian facilities are brought into compliance over time. Specific work will
also trigger a requirement to bring certain ADA facilities into compliance at the same time as the work is
performed. Examples of specific work that triggers ADA improvements include when a new bridge is
constructed, when new sidewalk is added to a bridge, or when the level of work on a bridge is
considered to be an “alteration.” Activities that reduce the accessibility of sidewalks from meeting
standard to being below standard or that reduce the accessibility of a below‐standard service are not
allowed. Additionally, a project’s scope of work must not be modified solely to avoid triggering ADA
upgrades.
ODOT has established design standards that govern ADA‐related design features.. Deviations from the
design standards require a design exception.
PathofTravelWhen alterations affect the usability of or access to a bridge sidewalk, it is necessary to ensure that the
path of travel to the sidewalk is readily accessible to people with disabilities to the maximum extent
feasible. The path of travel must be unobstructed and continuous so that the altered sidewalk may be
approached, entered, or exited from approaching sidewalks, streets, and shoulders.
In rural areas or where sidewalks are not present, expect pedestrian travel on or along the roadway
except where prohibited. The pedestrian access route would be in the shoulder or in the roadway when
there is no shoulder. When a sidewalk is not present, treat the shoulder or roadway as a service when
determining the impact of alterations.
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WORKACTIVITYTRIGGERSThe US DOJ/FHWA memorandum1 defines an “alteration” as: A change that affects or could affect the
usability of all or part of a building or facility. Alterations of streets, roads, or highways include activities
such as reconstruction, rehabilitation, resurfacing, widening, and projects of similar scale and effect.
Activities defined as maintenance by the US DOJ/FHWA on streets, roads, or highways, such as filling
potholes, are not alterations. Upgrade each facility or part of a facility that is altered to be readily
accessible and usable by individuals with disabilities to the maximum extent feasible.
Examples of alterations of bridges include rail retrofit, widening, bridge deck concrete overlays, and
asphalt concrete overlays when part of a full width paving project that extends beyond the bridge.
Further, when changes are made that affect the accessibility or usability of the sidewalk, ADA features
need to be addressed. An existing bridge is considered to have a sidewalk when the horizontal surface is
30 inches nominal. Conversely, when the surface is less than the defined width, it is not considered to be
a pedestrian facility. Pedestrian facilities can exist in the shoulder or in the roadway on bridges without
sidewalks.
The work types in the list below are not considered “alterations” and are considered maintenance
activities. The list is not exhaustive. Evaluate additional activities on the basis of their impact to the
usability of the pedestrian facility; activities that cause such impacts are considered “alterations”.
Individual activities that do not result in changes to usability of the pedestrian facility:
o Structural deck overlays, premixed polymer concrete overlays, deck seals, and ACWS
overlays, provided these activities do not overlap the pedestrian facility (sidewalk,
shoulder, and/or crosswalk)
o Thin bonded polymer system overlays and deck seals that do or do not overlap the
pedestrian facility (sidewalk, shoulder, and/or crosswalk)
o Deck repair patching, repair of deck soffit, full depth deck repair when these activities
do not span the length of the bridge or more than ¾ of the width of the pedestrian
facility (sidewalk, shoulder, and/or crosswalk)
o Under deck superstructure repair
o Spot sidewalk repair
o Repair of sidewalk soffit, repair of longitudinal sidewalk beams, repair of cantilevered
sidewalk supports
o Bridge Painting, cathodic protection
o Repair in‐kind of existing bridge rails
o Concrete patching of superstructure elements, prestressed components, concrete
surface finishing
o Bonded structural strengthening (FRP, titanium, other metals, surface or near‐surface),
resin injection of concrete cracks
o Seismic retrofits
o Expansion joint repair or replacement
1 http://www.fhwa.dot.gov/civilrights/programs/doj_fhwa_ta.cfm
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o Bearing device cleaning and lubrication
o Substructure or Foundation repair
TemporaryTrafficControlandWorkZonesFor temporary traffic control and construction work, avoid impacting the pedestrian path of travel to the
maximum extent feasible. If an existing pedestrian route is available and is impacted by work activities,
provide a temporary ADA‐accessible route for pedestrian traffic. For example, if an existing shoulder
across a structure is two feet wide, provide a two‐foot temporary pedestrian access route for pedestrian
traffic.
If an existing pedestrian route meets ADA requirements and is impacted by work activities, provide
temporary ADA‐accessible facilities for pedestrians and ADA road users. The type and extent of
accommodations used to mitigate pedestrian route impacts may change depending on the scope and
duration of the work activities. Provide a safe, accessible means to convey users of the route to the
destinations originally provided by the existing pedestrian access route.
Include temporary advance notification signing (ten days prior to impacting the facility) and the
following for the temporary pedestrian access route, as applicable to the type and configuration of the
temporary route:
1. Temporary signing:
a. In advance of a pathway closure point at the nearest alternate route point
b. At the pathway closure point
c. Along the route, at junctions or decision points, for both directions
2. Temporary sidewalk ramps
3. Temporary, detectible surfacing
Depending on the type and duration of work, the temporary pedestrian access route may use:
1. Pedestrian detours using local infrastructure
2. Pedestrian on‐site diversions
3. Escorted travel through the impacted areas
a. Vehicular escort by public or private means
i. Contracted shuttle buses with on‐call or scheduled services
ii. Voucher system for local bus network or cab services
b. Pedestrian escort on foot (e.g. Contracted worker/Flagger)
4. Temporary lane/shoulder closures – Repurposing the space for pedestrian routes
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IntersectionsonBridgeStructuresIn some cases, intersections are located on bridge structures. The ADA requires providing or upgrading
curb ramps at intersections in projects that either provide sidewalk or alter streets, roadways, or
highways that span from one intersection to another. If a bridge alteration project includes an
intersection it triggers the obligation to provide ADA compliant curb ramps at the intersection. Refer to
Appendix 1: DesignofBridgeCurbRamps or Appendix 2: Examples for additional
guidance.
RailRetrofitorReplacementFor installation of bridge rail retrofit or bridge rail transitions at bridge ends, do not decrease the width
of an existing sidewalk unless the final sidewalk width satisfies ADA requirements. A design exception is
required for sidewalk clear width less than ODOT standard width.
Bridge rail replacement requires ADA upgrades unless a design exception is obtained.
SidewalkandPassingSpacesWhen the work activities on the sidewalk are considered to be an alteration, the pedestrian access route
must be readily accessible to people with disabilities. Address accessibility barriers which include narrow
passages or routes lacking sufficient turning or passing space.
Narrow passages are required to contain a 5 feet by 5 feet of level (≤2% slope), clear turning or passing
space when the passage is longer than 200 feet. Common places where a sidewalk is less than 5‐feet
wide are alongside bridge structural elements. Even if passing spaces are available, the reduced width
at a bottleneck may preclude access to some users. Generally, as long as the bottleneck enables at least
4‐feet of sidewalk access, ADA requirements for width are met. Where the bottleneck reduces the
sidewalk less than 4‐feet or where the width of the sidewalk itself is less than 4‐feet, an accessibility
barrier exists. For bridges with existing sidewalks having less than 4 feet of horizontal surface, improve
the sidewalk width to at least 4 feet with 5‐foot by 5‐foot passing spaces at intervals no greater than 200
feet along the path, or 5 feet of width throughout the path. For bridge sidewalks greater than 4 feet
wide, but less than 5 feet wide, provide turning spaces when the bridge length is 200 feet or greater.
Deviations from the design standards due to historic or technical considerations require a design
exception.
DESIGN CONSIDERATIONS
HistoricBridgesFor bridges that are considered a historic resource, ADA modifications may threaten or destroy the
significance of historic features of the bridge. It is important that the Region Environmental Coordinator
and the Historic Resource Coordinator to work with the State Historic Preservation Office (SHPO) when
there is a project on a historic bridge; this includes ADA considerations. Where upgrading accessibility
would conflict with federal law regarding historic preservation, neither law supersedes the other.
Assess the impact of the ADA upgrades and determine whether an Adverse Effect is made to the historic
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significance of the bridge structure. Achieve the ADA accessibility requirement to the maximum extent
feasible within the constraints that it does not have an Adverse Effect on historic preservation.
When there is a conflict between federal historic preservation requirements and ADA requirements, a
Design Exception is required to validate and justify any deviation from meeting ADA standards. A
required supporting document in the Design Exception is a letter from SHPO declaring that an adverse
effect would be caused by meeting the full requirements of the ADA. In the letter, describe whether
incremental ADA improvements would create adverse effects.
TechnicalInfeasibilityandDesignExceptionADA compliance requirements are not the same as ODOT geometric design standards. The Roadway
design exception process is used when geometric standards cannot be achieved for a number of good
reasons. ODOT also uses the Roadway design exception process to document when it is technically
infeasible to meet all the ADA criteria. Early coordination before DAP with the ODOT Roadway
Engineering Unit regarding impacts to either the ODOT geometric standards or the ADA facility is
especially important. Justification for not meeting standards is a required section of the design
exception request. While costs can be used to justify exceptions to geometric standards it is not a
justification for ADA criteria. See Chapter 14 of the ODOT HDM – Design Exception Process2 for the
design exception process.
4RStandard4R or modernization projects are considered the highest level of design and as such ODOT geometric
standards for horizontal and vertical alignments, super elevation, lane width, shoulder width, sidewalk
width are expected to be used. Document the justification for any non‐standard feature not meeting the
geometric design standards in a design exception request. ODOT geometric standards for sidewalk width
are wider than the minimum ADA compliance width but the ODOT geometric standard of 7 foot wide
sidewalks are required unless there is an approved design exception.
3RStandard3R or Rehabilitation projects are more common than 4R projects. These projects are able to retain
many of the existing geometric features even when they do not meet full ODOT geometric design
standards. On a 3R project a sidewalk that does not meet the full 7 foot width but does meet the ADA
criteria of a 5 foot wide sidewalk, a design exception is not required. When the sidewalk width is below
5 foot, a design exception is required and mitigate the non‐standard width by providing a 5 foot by 5
foot level landing every 200 feet along the sidewalk. Other geometric features that are non‐standard
need to be evaluated by the Roadway designer for design exception requirements.
1RRoadPaving1R or Resurfacing projects are the most common project type. These projects have a narrow scope
defined to just surface treatments. When road pavement surfacing extends from one intersection to
another, and stays at either the edge of pavement or the curb line when crossing through intersections,
2 https://www.oregon.gov/ODOT/HWY/ENGSERVICES/Pages/design_exceptions.aspx
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provide or upgrade curb ramps at all transverse crossing locations. Document curb ramps that include
technically infeasible features with a design exception request.
SingleFunctionStandardSingle Function projects are very limited in scope. The feature addressed in a single function project is
to use 4R design standards for that specific feature. Design exceptions are not required for non‐
standard geometric elements not impacted by the single function work. If the sidewalk is not being
modified, but the railing is being modified, which reduces the width of the sidewalk below ADA
minimum width, a design exception is required. If the reduction in usable sidewalk width retains the
minimum ADA width, but not the ODOT standard width, a design exception is required for not meeting
the ODOT standard.
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Appendix 1: DesignofBridgeCurbRampsWhen an alteration project includes a bridge with a sidewalk, upgrade any pedestrian curb ramps to
meet ADA compliance. In most cases, a bridge sidewalk is adjacent to:
a shoulder
a sidewalk
an adjacent intersection
The following guidance is for designing accessible transitional ramps for each of these facilities.
BridgesidewalktoashoulderBridge sidewalks may either be aligned within the shoulder of a roadway or they may be partially or
completely outside of the shoulder area. Requirements for the ramp from the sidewalk to the shoulder
are: a cross slope of less than 2% (1.5% design), a running slope of less than 8.33% (7.5% design) and a
level landing with cross and running slopes less than 2% (1.5% design). If the end of the existing bridge
sidewalk does not have a cross slope of less than 2%, provide an additional sidewalk panel that
transitions the sidewalk cross slope to the 2% cross slope. The following describe ramp treatments
based on their alignment to the shoulder
a. Tapered shoulder ramp
When a bridge sidewalk is partially or completely outside of the shoulder area, provide a level
landing that acts as a turning space at the bottom of the ramp and a tapered shoulder to
transition users to the existing shoulder as illustrated in Figure 1.
Figure 1: Bridge curb ramp to tapered shoulder with
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b. Continuous shoulder ramp
When the bridge sidewalk is within the full width of the shoulder provide an ADA compliant
ramp from the sidewalk to the shoulder. The image in Figure 2 illustrates a transitional panel at
the end of the bridge sidewalk to transition from the existing cross slope of the bridge to a panel
with an ADA compliant cross slope of 2% at the top of the ramp.
Figure 2: Bridge curb ramp to continuous shoulder with transitional panel
BridgesidewalktoanapproachingsidewalkBridge sidewalk curb heights are generally greater than standard curb heights. Provide a transition panel
between existing roadway sidewalk and bridge sidewalk. Ensure the transitional ramp has a running
slope less than 8.33% finished (7.5% design) and a cross slope of less than 2% finished.
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BridgerampsatanintersectionsIntersections are presumed have crosswalks at all approaches. Crossings must be ADA accessible. When
sidewalks exist at an intersection, ADA compliant curb ramps are required. Unless technically infeasible,
provide two curb ramps at each corner; one to serve each direction of pedestrian travel. Follow ODOT
Standard curb ramp guidance for ADA compliant curb ramp design.
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Appendix2:Examples
Paving in Lane
Project: Paving between fog lines through intersections. Existing Conditions: Roadway with paved shoulder. Bridge with sidewalks (width ≥ 30”).
Required: ADA ramps at all crossings, but ramps not required to bridge sidewalk.
Full‐width Paving Near Bridge Approach
Project: Full‐width paving on highway surrounding bridge. Existing Conditions: Roadway with paved shoulder. Bridge with sidewalks (width ≥ 30”).
Required: ADA ramps to bridge sidewalks.
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Full‐width Paving to Bridge
Project: Full‐width paving to edge of concrete bridge deck. Existing Conditions: Roadway with paved shoulder. Bridge with sidewalks (width ≥ 30”).
Required: ADA ramps to bridge sidewalks.
Rail Retrofit
Project: Rail retrofit that would reduce the clear width of the existing sidewalk below 4 feet. Existing Conditions: Roadway with paved shoulder. Sidewalk width insufficient to accommodate wheelchairs and rail retrofit.
Required: Ramps installed along highway to sidewalks with increased clear width to 4 feet. Lane width decreased to allow for increased sidewalk width. 5 foot by 5 foot sidewalk passing spaces on bridges over 200 feet long. Design Exception may
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be required for lane width.
Full‐width Paving Over Bridge with Brush Curb
Project: Full‐width paving over bridge. Existing Conditions: Roadway with paved shoulder. Bridge without sidewalk (<30” width).
Required: Ensure that path of travel is maintained along shoulder.
Rail Retrofit – Brush Curb
Project: Rail retrofit on bridge with brush curb (width <30”). Existing Conditions: Roadway with paved shoulder. Bridge without sidewalk (<30” width).
Required: Ensure that existing path of travel is maintained along shoulder.
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1.16 (RESERVED)
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Analysis / Research / Other Supporting Data:
None Attached:
Bridge Engineering Section Response:
Accepted for consideration as submitted Accepted for consideration as noted Proposal tabled, see Remarks Proposal not accepted, see Remarks
Remarks:
Craig Shike Bridge Design Standards Reviewer
Date
Alex Lim Bridge Design Standards Engineer
Date 5/3/2017
Cc: file