Journal of Public Works & Infrastructure (2010)


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Journal of Public Works & Infrastructure (2010)

  1. 1. Journal of Public Works & Infrastructure Volume 2 Number 3Asset management for ADA complianceusing advanced technologiesFranz LoewenherzReceived: 6th October, 2009City of Bellevue, Transportation Department, 450 110th Ave. NE, Bellevue, WA 98009, USATel: +1 425 452 4077; E-mail: floewenherz@bellevuewa.govFranz Loewenherz has more than 18 years evaluation update to assess its programmeof transportation industry experience responsibilities for existing pedestrian facilitiesworking in both the public and private in the public rights-of-way. The Citysectors. In his current position as a senior employed innovative technologies to documenttransportation planner with the City of Bel- barriers and prioritise improvements wherelevue, Washington, he is involved in a most needed. Implementation of this technologywide range of planning assignments development and compliance effort involved aincluding the light rail route extension coordinated staffing and funding commitmentfrom Seattle to Bellevue, the City’s pedes- from the City of Bellevue, Federal Highwaytrian and bicycle master plan, and corri- Administration and King County, with techni-dor studies that assess land use and cal support from Starodub Inc., an engineeringtransportation interactions. He is project services firm. This case study examines onemanager of the City of Bellevue’s Ameri- medium-sized city’s approach to conducting acans with Disabilities (ADA) sidewalk and comprehensive asset data inventory and pedes-kerb ramp inventory. trian facility condition assessment.ABSTRACT Keywords: ADA, sidewalk, kerbThe Americans with Disabilities Act 1990 ramp, inventory, inertial profiler(ADA), is a landmark civil rights law that technologyprohibits discrimination based on disability.Title II of the ADA requires state and local INTRODUCTION[ED1]governments to make their programmes and ser- The City of Bellevue is a community ofvices accessible to persons with disabilities. 120,000 residents. According to the 2000This requirement extends not only to physical census, approximately 15 per cent of Belle-access at government facilities, programmes and vue residents live with a developmental,events — but also to pedestrian facilities in physical and/or mental disability. Buildingpublic rights-of-way. To comply with the pedestrian facilities now and for the futureADA, every state and local government is means taking into consideration not onlyrequired to prepare a self-evaluation report to the reported disabilities of residents butidentify programme access issues. From this, a also the physical and cognitive changestransition plan is required, with a schedule that many individuals experience over theidentifying corrective measures to achieve a bar- course of their lifetimes. Looking to the Journal of Public Works & Infrastructurerier-free environment. In 2008, Bellevue under- future, an increased percentage of the Vol. 2, No. 3, 2009, pp. 00–00 # Henry Stewart Publications,took an ADA sidewalk and kerb ramp self- population with disabilities is expected as 1755–0955 Page 1
  2. 2. Asset management for ADA compliance using advanced technologies the category of citizens 75 years of age and disabilities to reach their desired destina- older is growing at a rate more than four tions in the community and to enjoy the times as fast as the general population in benefits of city services, programmes and Bellevue. It is estimated that 85 per cent of activities. Where sidewalks are provided, Americans who live to their full life expec- public agencies are required to ensure that tancy will suffer a permanent disability. continuous, unobstructed sidewalks are The City of Bellevue has a long and dis- maintained in operable working condition. tinguished history of working to address This guidance is supported by a steady the transportation needs of its residents stream of cases interpreting ADA provi- with disabilities. On 16th November, sions. 1992, the Bellevue Council adopted Reso- On 22nd January, 2004, in the case of lution 5586, establishing a programme to Barden v Sacramento, the 9th Circuit Court promote full participation for all people ruled that sidewalks were a ‘programme’ who use the City’s services and pro- under ADA and must be made accessible grammes. In April 1997, Bellevue received to persons with disabilities. Prior to this a Certificate of Appreciation from the decision, it was commonly understood that Governor’s Committee on Disability Issues the minimum requirement for achieving and Employment. The award focused on programme accessibility, in an existing making facilities accessible, addressing public right-of-way that is not otherwise access barriers to internal and external cus- being altered, was through the installation tomers, and providing flexibility in the of kerb ramps at locations where existing workplace. pedestrian walkways cross kerbs. The The City of Bellevue remains com- court decision in the Barden case relied mitted to ensuring that the civil rights of upon the language in ADA regulations people with disabilities are preserved and requiring city ADA transition plans to that it complies with regulations stipulated include a schedule for the installation of in the Americans with Disabilities Act kerb ramps at intersections, holding that 1990 (ADA). Bellevue’s comprehensive this requirement would be meaningless if plan (Policy TR-26) directs staff to: the sidewalks between kerb ramps were inaccessible. The Barden decision made ‘address the special needs of physically clear that public entities are required to challenged and disabled citizens in invest in the repair of public sidewalks and planning, designing, implementing, and maintain them free from barriers, physical maintaining transportation improve- defects and other conditions that may deny ments, particularly non-motorised pedestrians with disabilities access to side- improvements, and other transportation walks. facilities, and in delivering transportation Ignoring the law can be expensive now services and programmes, in accordance that it is understood that pedestrian paths with the Americans with Disabilities fall under ADA. In 2007, the City of Chi- Act’. cago settled one of the largest ADA cases in history, agreeing to spend US$10m a This policy commitment is carried forward year for five years on sidewalk accessibil- in all phases of project and service develop- ity, in addition to the US$18m it spends ment provision. annually on sidewalk maintenance. Furthermore, poorly maintained pedestrian ADA COMPLIANCE infrastructure can lead to expensive perso- Accessible sidewalks enable people with nal injury lawsuits.Page 2
  3. 3. Goodger, Parker and GuyPROJECT APPROACH data quickly, the ‘yes/no’ clipboardIn 2008, Bellevue undertook an ADA side- approach does not offer a precise under-walk and kerb ramp self-evaluation update standing of which areas have the mostto assess its programme accessibility need.responsibilities for existing pedestrian facil- Bellevue determined that a new solutionities in the public rights-of-way. The pro- to quickly and accurately document theject followed a three-phased approach: (i) type, severity, and location of sidewalkdata collection; (ii) database analysis; and and ramp barriers in the City would be(iii) barrier ranking. As indicated in Figure most efficient. A number of options were1, the self-evaluation process involved the considered for gathering data on its 321disability community in the identification miles of sidewalk and 4,586 kerb rampsof priorities for improving pedestrian locations (1,041 locations lacked rampaccessibility in Bellevue. access), including traditional survey and light detection and ranging. Based on earlyPhase 1: Data collection tests, the City concluded that either ofThe traditional ADA inventory process is these approaches could cost more thantime-consuming and imprecise. Most juris- US$1m.dictions undertaking ADA sidewalk and City staff learned about inertial profilerkerb ramp inventory efforts rely on data systems, which have used to measure pave-collectors to choose between a ‘yes’ or ‘no’ ment defects since the 1970s. Profilers areresponse in recording ADA compliance. typically mounted on motor vehicles andWhile this enables jurisdictions to collect used in both the aerospace and roadwayFigure 1[ed11]: Visual representation of Bellevue’s project approach Page 3
  4. 4. Asset management for ADA compliance using advanced technologies construction industries for measuring the surface variations that can make a sidewalk smoothness of pavement surfaces on air- difficult to navigate. A tray and handle-bar craft landing strips and the highway mount support a notebook computer that system. An interdepartmental team at the offers an interactive, real-time display City of Bellevue partnered with federal during data collection. The accompanying and regional agencies to adapt this profiler software produces a text file compatible technology to the task of inventorying and with the City’s geographic information mapping the degree to which sidewalks systems (GIS) asset management database. and kerb ramps in the City’s right-of-way Bellevue staff worked with colleagues at meet ADA standards. the FHWA and King County to ensure The technology, developed through a that the resulting technology would be of pilot programme with the Federal High- broad benefit to federal, state and local way Administration (FHWA), uses an government entities. From a cost savings ultra-light inertial profiler (ULIP) perspective, the total project expense of mounted on a Segway scooter (Figure 2). US$285,000 in staffing, software and hard- The device’s displacement laser, three ware reflects a 70 per cent saving over the accelerometers, optical trigger, distance amount originally estimated to conduct a measurement instrument, and gyroscope traditional survey or light detection and are designed to measure the sidewalk sur- ranging approach. Specific partnership face at a rate of 10,000 records per second. contributions included: Together, these devices capture highly- accurate information about slope and small . City of Bellevue: Staff in both the trans- portation and IT departments collabo- Figure 2: City of Bellevue’s ULIP and Segway rated in overseeing this project. Staff human transporter equipment managed the three-agency partnership, field-tested the technology, verified results using other measurement systems, collaborated with FHWA and Starodub, Inc. engineers to refine the software, and developed programming scripts that synthesise ULIP data records into the city’s GIS system. These staffing costs were US$70,000. . Federal Highway Administration: The FHWA is responsible for ensuring access for persons with disabilities to pedestrian facilities within the public right-of-way. The Office of Pavement Technology agreed to have Starodub, Inc. fabricate the ULIP (at an estimated cost of US$120,000) in 2006. The device was loaned to Bellevue at no cost to the city. FHWA provided an additional US$50,000 in 2007 for software refinements. . King County: As a transit operator in the region, King County is responsiblePage 4
  5. 5. Goodger, Parker and Guy for the provision of ADA kerb-to- kerb measurement devices, such as digital paratransit service as a safety net for smart-level readings, before a decision was persons whose disabilities prevent use of made to employ this technology citywide accessible non-commuter, fixed-route (see Figure 3). bus service. The Department of Acces- During the 2008 citywide inventory sible Services regards the data generated effort, the city employed quality assurance/ from the ULIP technology as saving quality control (QA/QC) protocol for time and money they would otherwise validation testing of the software and hard- spend conducting accessible pathway ware. The ULIP technology’s efficacy was assessments. For the opportunity to confirmed in 2008, when two field techni- partner in Bellevue’s research cians were able to inventory the city’s endeavour, King County provided entire pedestrian system within a few US$45,000 to support the two staff months’ time. One technician operated the members involved in the inventory ULIP and conducted the sidewalk inven- process and assisted with the public tory (321 miles), and a second technician outreach process. rode a bicycle and used a Topcon GMS-2 handheld GPS receiver to conduct theBecause it was a new technology, the City kerb ramp inventory (4,586 locations).of Bellevue sought confirmation that the The National Cooperative Highwaydata acquired from the ULIP platform Research Program’s ADA Compliance atwould be reproducible and accurate. Transportation Agencies: A Review of Prac-During the 2007 trial period, Bellevue and tices identifies the technical precisionStarodub, Inc. staff undertook numerous offered by Bellevue’s approach as a besttests comparing grade and cross-slope mea- practice. The report notes that ‘efforts suchsurements from the ULIP and alternative as those at the City of Bellevue, Washing-Figure 3: Validation testing graph showing very good agreement between the ULIP (four runs) andsmart-level data Page 5
  6. 6. Asset management for ADA compliance using advanced technologies ton, that rely on the collection of large first step in arriving at these site-specific datasets at extremely fine spatial and tem- calculations. poral disaggregation levels have the poten- During the data-processing step, the user tial to significantly automate the specifies the grade and cross-slope window identification of non-compliant locations size in feet to be applied in a moving aver- in the field’.1 age computation to the ASCII text files from the ULIP data acquisition. Figure 4 Phase 2: Database analysis shows the resulting grade ranges corre- The City of Bellevue’s ADA sidewalk and sponding to ten window sizes. As indi- kerb ramp database provides geographic cated, the most pronounced sidewalk data with both positional accuracy — the profile values are noted when the window digital representation of how a barrier con- size is in the 300–600 mm (1–2 ft) range. forms to the actual location found in the In this test site, one can see that with a field (better than what is possible with 300–600 mm (1–2 ft) window size, the streaming GPS); and attribute accuracy — grade value approaches 8 per cent. The the digital representation of a barrier is larger the window size value, the more represented in a manner consistent with dampened out the features of the sidewalk actual conditions found in the field (per- profile. So, at a 15 m (50-ft) window size, centage running slope, percentage cross- the test site appears to have a flat grade slope, inches of vertical separation, etc). profile. Defining the window size (travel length Guidance in defining the window size for computing representative measure- over which to assess the data was found in ment) for data processing was a critical the FHWA’s Designing Sidewalks and Trails Figure 4: The effects of different grade windows on data output valuesPage 6
  7. 7. Goodger, Parker and Guyfor Access. This report advises that grade review of data.and cross-slope ‘should be measured over GIS played a pivotal role in the project2-ft [600 mm] intervals, the approximate from data acquisition (organising the mil-length of a wheelchair wheelbase, or a lions of data points generated during thesingle walking pace’.2 Adherence to the study) to creating a web-based mappingFHWA interpretation of features in the interface for asset management and com-data set provided quality assurance in the pliance monitoring. The resulting ADAattribute accuracy of the resulting database. sidewalk and kerb ramp self-evaluation is Once the field data collection and valid- documented on the City’s intranet. Thisity checks were performed, it was neces- internal web interface maps all non-stan-sary for the raw data to be processed so dard data points related to kerb ramp loca-the data could be stored in the City’s cen- tion and compliance rating — at thetralised GIS database for analysis and block-face level — including sidewalkreporting. To facilitate the data conver- obstructions, heaving, running slope andsion, Bellevue staff created Python scripts cross-slope (Figure 5). Additional function-and tools using linear referencing to pro- ality of this geospatial database includes thecess ULIP raw data into a useful GIS form. ability to search and/or turn off certainAutomating the process with scripts and barrier types and generate reports of thecustom interfaces was important both to barrier information.limit manual efforts and to allow for daily The ADA viewer interface creates aFigure 5: City of Bellevue’s web-based ADA mapping viewer interface Page 7
  8. 8. Asset management for ADA compliance using advanced technologies platform from which staff can retrieve . Sidewalk maintenance and repair information on ADA barriers in the public programme: The streets division right-of-way, informing the following personnel clear vegetation and debris accessibility programmes: from sidewalks adjacent to arterial streets, inspect sidewalks for damage, . New development: New development or and when needed, repair walkways. redevelopment projects must include sidewalks and kerb ramps. Phase 3: Barrier ranking . Citizen request programme: Citizens The ADA guidelines indicate which fea- submit requests to have a new kerb tures in the public rights-of-way are non- ramp installed or have an existing kerb standard but do not say which of these ramp repaired at any location within non-standard features should be replaced the City. first. After determining which facilities do . Annual installation, repair, and mainte- not meet standards, the City developed a nance programme: The City’s transporta- prioritised list of improvement require- tion department repairs sidewalks and ments in conjunction with the disability installs new kerb ramps annually as part community (Figure 6). of routine maintenance. Bellevue’s GIS-based barrier ranking . Street-related capital improvement projects: analysis results in a combined activity and Sidewalks and/or kerb ramps are impedance score for every sidewalk and installed and/or repaired in all street- kerb ramp in Bellevue. A high activity related capital improvement projects (eg score is representative of areas where street widening or other street pedestrian activity (especially among per- upgrades). sons with disabilities) is likely to be great- . Overlay construction projects: The City est, based on demographic, land use and includes the installation of kerb ramps transportation conditions. A high impe- as part of street overlay projects. dance score is representative of areas where Figure 6: Criteria influencing the barrier ranking scores. Bellevue used GIS to overlap data layers, each representing one of several characteristics, and determine the cumulative intensity of all characteristics throughout the city.Page 8
  9. 9. Goodger, Parker and Guythe quality of existing pedestrian infra- detailed information on these and otherstructure is poor for persons with disabil- ADA considerations can be found atities, based on barriers documented in the and kerb ramp inventory. The reports.htm):key principle here is to assign a high rank-ing on a needs basis, not necessarily to the . Sidewalk cross-slope: As indicated insidewalks and kerb ramps in the worst Table 2, over 50 per cent of Bellevue’scondition but rather to those that would cross-slope measurements 8 per cent areprovide the most benefit to people with attributable to driveway aprons. Thisdisabilities. number increases as cross-slope values The point values assigned to the various increase, with 70 per cent of cross-slopenon-standard features in the impedance measurements 10 per cent attributable tocalculation arose from consultations with driveway aprons. Overall, 19 per cent ofmembers of the disability community in all non-standard cross-slope measure-Bellevue. The outreach effort included sur- ments are attributable to drivewayveys, focus groups, public meetings and aprons constructed like ramps, withconversations with residents at sidewalk steep, short side flares (Table 2).and kerb ramp locations. . Sidewalk grade (running slope): According to ADA Accessibility GuidelinesRESULTS (ADAAG), the sidewalk grade shouldBellevue’s pedestrian facilities are evaluated not exceed 5 per cent. However, gradesagainst a number of ADA standards in the are often too difficult to control in theCity’s sidewalk and kerb ramp self-evalua- sidewalk environment because sidewalkstion report. The following are the grade follow the path of the street and theand cross-slope accessibility considerations: natural topography of the area. Belle-(i) maximum grade is 5 per cent on con- vue’s GIS database played a pivotal roletinuous runs; (ii) sidewalks adjacent to in determining which of the non-existing roadways may follow grade of standard sidewalk grade profiles wereroadway; and (iii) cross-slope shall not deemed technically infeasible due toexceed 2 per cent. As reflected in Table 1, topographic roadway factors. Bellevue32 miles (82 per cent) of non-standard staff developed a GIS script that enabled agrade measurements are found to have comparison of every non-standardprofiles of 5–8.33 per cent. Below are sidewalk segment to the grade of thesome of the findings on grade and cross- adjacent roadway. Adjacent roadwayslope from the inventory effort (more grade profiles were derived from a digital elevation model, a representation of ground surface topography. CriteriaTable 1: Results of sidewalk cross-slope ana- were then used to filter out 95 miles oflysis non-standard sidewalk grade locations deemed technically infeasible. Bellevue’sGrade category Length (miles) % decision to screen profile data is consistent with currently recommended best5–8.33% 32 82 practices from the US Access Board and8.34–10% 4 10 FHWA to make allowances for the10.01–12.5% 2 512.5%+ 1 3 sidewalk grade of the associated roadway.Total 39 100 . Kerb ramp panel grade and cross-slope: Table 3 reflects the combined grade and Page 9
  10. 10. Asset management for ADA compliance using advanced technologies Table 2: Results of sidewalk grade analysis Cross slope within Cross slope without Cross slope Total length Driveway Buffer Driveways % Attributable category (miles) (miles) (differences) Driveways 2–4% 134 18 116 13 4–6% 49 9 41 17 6–8% 15 5 10 31 8–10% 7 4 3 54 10%+ 7 5 2 70 Total 212 40 172 19 Table 3: Results of kerb ramp grade and cross-slope analysis Ramp running slope <8.3% 8.3%–10% >10% Ramp cross slope (Standard) (Non-standard) (Non-standard) Totals <2% (Standard) 502 (14%) 224 (6%) 369 (11%) 1,095 (31%) 2%–4% (Non-standard) 459 (13%) 209 (6%) 338 (10%) 1,006 (29%) >4% (Non-standard) 564 (16%) 253 (20%) 1,300 (37%) 1,410 (100%) Totals 1,525 (43%) 686 (20%) 1,300 (37%) 3,511 (100%) cross-slope statistics for Bellevue’s kerb ramp facilities. Data collected from existing 3,511 kerb ramps. As indicated, this assessment enable city staff to: (i) 502 (14 per cent) kerb ramps in Bellevue determine if a sidewalk or kerb ramp were found to have both a standard meets intended design specifications and running slope (<8.3 per cent) and guidelines; (ii) catalogue feature and main- standard cross-slope (<2 per cent). At tenance information; (iii) identify portions the opposite end of the spectrum, 593 of sidewalks needing accessibility improve- (17 per cent) kerb ramps in Bellevue ments; (iv) quantify the extent of the work were found to have both high running required; and, (v) add pedestrian informa- slope (>10 per cent) and high cross- tion to the City’s GIS database. The barrier slope (>4 per cent). Feedback from the ranking analysis used in this process was disability community indicates that the product of a public consultation pro- ‘warp’ (the combined effect of high cross cess, which the City believes reflects the and running slopes) negatively impacts interests of Bellevue residents and responds accessibility. to the stated needs of people with disabil- ities in the community. NEXT STEPS The development of Bellevue’s ADA Bellevue’s ADA sidewalk and kerb ramp transition plan update relies heavily on the self-evaluation report is a comprehensive barrier identification and rankings con- analysis of the city’s existing sidewalk and tained in the sidewalk and kerb ramp self-Page 10
  11. 11. Goodger, Parker and Guyevaluation. Transportation staff have been approaching their ADA compliance pro-working to complete the department’s gramme:transition plan update process by Spring2010. To do this, key assumptions regard- . The ADA provides comprehensive civiling barrier prioritisation, corrective action right protection to individuals withcosts, programming, and supportive poli- disabilities. ADA Title II requires everycies need to be evaluated and documented. state and local government to prepare aOnce completed, the transportation self-evaluation plan to identifydepartment’s transition plan update for the programme access issues. From this, apublic rights-of-way will be integrated transition plan is required showinginto the citywide transition plan that policies and practices to achieve aaddresses the other key areas of ADA barrier-free environment. Failure toaccessibility: access to public facilities and manage ADA compliance properly hasto city programmes and services. Comple- prompted action by the Department oftion of the update to the citywide transi- Justice and proven costly to many citiestion plan is anticipated in 2010. throughout the country due to an The relationship between the self-eva- increasing amount of litigation.luation report and the ADA transition plan . Public works departments are facingis illustrated in Figure 7. increased pressure to determine cost- effective and efficient methods forLESSONS LEARNED compliance with ADA accessibilityThe following information is intended to standards. Because agencies at all levelsassist other local government agencies are required to respond to ADAFigure 7: The relationship between the self-evaluation report and the ADA transition plan Page 11
  12. 12. Asset management for ADA compliance using advanced technologies mandates, developing partnerships outreach effort that provided a wide increases the cost-effectiveness of range of stakeholders from the disability compliance efforts. The coordinated community with improved access to staffing and funding commitment from the decision-making process. This the three participating agencies approach to community engagement is (FWHA, King County and the City of consistent with ADA Title II guidance Bellevue) made it possible to undertake requiring governmental entities to Bellevue’s proposal to assess the applic- ‘provide opportunity to interested ability of inertial profiling technology persons and groups to participate in in identifying existing facilities that self-evaluation leading to transition limit access for persons with disabilities. plan’. . As a new technology, the City of . GIS played a pivotal role in the project Bellevue sought confirmation that data from data acquisition (ie organising the acquired from the ULIP platform were millions of data points generated during repeatable, reproducible and accurate. the study) to project prioritisation (ie Numerous tests were carried out determining priorities for improve- comparing grade and cross-slope ments and displaying the corresponding measurements from the ULIP and alter- locations on a variety of mapping inter- native measurement devices (eg digital faces). The result is a mapping interface smart-level readings). Bellevue and on the City’s intranet that documents FHWA staff undertook a rigorous all non-standard data points related to review of the data before a decision was sidewalks and kerb ramps. The ADA made to employ this technology in a viewer interface creates a platform from citywide inventory effort. During the which city staff can retrieve information citywide inventory effort, the city on barriers in the public right-of-way, employed QA/QC protocol for valida- informing the City’s corrective tion testing of the software/hardware measures on where to make repairs to equipment. sidewalks and kerb ramps. . After several years in development, . The City is using the data from the self- Bellevue’s ULIP is the first technology evaluation inventory to program of its kind that enables jurisdictions to needed implementation resources complete an ADA condition assessment through the ADA transition plan time inventory quickly and accurately. Belle- horizon. A number of mechanisms are vue’s project — identified as a best in place to make sidewalks accessible to practice in Asset Management Approaches people with disabilities, including to ADA Compliance — is distinguished sidewalk maintenance, kerb ramp from the efforts of other jurisdictions retrofit and pavement overlay because actual values for running slope, programmes. In addition, the City is cross-slope and vertical separation are incorporating ADA improvements into captured along sidewalk block-faces its capital projects and as permit condi- rather than by field staff quickly traver- tions for development. sing a sidewalk network, determining . The rewards of ADA compliance come compliance through a simplistic ‘yes/no’ in many forms, not least of which is evaluation. establishing an accessible community . Bellevue’s self-evaluation report and that provides the public, including transition planning efforts were persons with disabilities, with access to informed by an extensive public the transportation network andPage 12
  13. 13. Goodger, Parker and Guy independent mobility regardless of age, physical constraint or income. Pedes- trian facilities are an essential part of the community infrastructure that indivi- ___________________________ duals use to gain access to the goods, 1Please check all figures have been services and social contacts that support appropriately cited in the text (NB Figs 7- their day-to-day existence and quality 9 renumbered as tables, as per journal of life. People with disabilities are better style) able to participate in the community if sidewalks and kerb ramps are accessible 2TS: Figure 1 near here because it is easier for them to reach 3TS: Figure 2 near here their desired destinations. 4TS: Figure 3 near here 5TS: Figure 4 near hereREFERENCES 6TS: Figure 5 near here1 National Cooperative Highway Research 7TS: Figure 6 near here Program (2008) ‘ADA Compliance at 8TS: Table 1 near here Transportation Agencies: A Review of 9TS: Table 3 near here Practices’, NCHRP 20-07 Task 249, Trans- 10TS: Figure 7 near here portation Research Board, Washington, 11Hi-res jpgs required for all artwork DC, available at: NotesDocs/20-07(249)_FR.pdf (accessed 16th December, 2009).2 Kirschbaum, J. B. et al. (1999) ‘Designing Sidewalks and Trails for Access’, Federal Highway Administration, Washington, DC, available at: gov/environment/sidewalks/ (accessed 16th December, 2009). Page 13