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From page 9...
... 9   This section summarizes the state of practice and other information related to the development and use of SPFs for pedestrians and bicycles. Section 2.1 summarizes the published literature reviewed relevant to the objectives of the research.
From page 10...
... 10 Pedestrian and Bicycle Safety Performance Functions pedestrian fatalities have eclipsed 6,000 annually. Before 2016, the last year that more than 6,000 pedestrian fatalities occurred in a year was 1990 when 44,599 fatalities occurred on the nation's highways in the United States.
From page 11...
... Literature Review and Survey of Practice 11   NHTSA 2020)
From page 12...
... 12 Pedestrian and Bicycle Safety Performance Functions Counting Method Accuracy Cost Advantages Disadvantages Methods to Overcome Barriers Manual on-site counts Depends on training and human error (1%–25%) Labor - High Equipment - Low Ease of implementation • Requires trained observers • Only for short-term counts • Standardized training • Volunteers Video (Manual)
From page 13...
... Literature Review and Survey of Practice 13   count data. Some agencies have been using passive and/or active monitoring of mobile devices.
From page 14...
... 14 Pedestrian and Bicycle Safety Performance Functions time (which is significantly high for manual counts)
From page 15...
... Literature Review and Survey of Practice 15   In a survey of over 60 practitioners, FHWA found that 87 percent had no experience extrapolating short-term counts over longer periods of time (FHWA 2011)
From page 16...
... 16 Pedestrian and Bicycle Safety Performance Functions not currently exist, and existing databases cannot accommodate continuous counts (Nordback et al.
From page 17...
... Literature Review and Survey of Practice 17   significantly reduce the costs of conducting manual counts and engage citizens and grow support for counting programs. 2.1.2.2.2 Practices for Building Support for Counting Programs and Procuring Funding Public and political support is a vital part of successful pedestrian and bicycle counting programs because funding is needed to support the program.
From page 18...
... 18 Pedestrian and Bicycle Safety Performance Functions useful for operations and planning purposes (e.g., time-dependent signal timing plans or planning for special events)
From page 19...
... Literature Review and Survey of Practice 19   Pinellas County, Florida, has also used surveys to determine trail usage for transportation purposes (Schneider et al.
From page 20...
... 20 Pedestrian and Bicycle Safety Performance Functions requires careful use of data and institutional review board (IRB) approvals.
From page 21...
... Literature Review and Survey of Practice 21   2.1.3.1 Count Data Most commonly available pedestrian and bicycle count data are collected for a short period around motor vehicle peak daytime travel periods. These short-duration counts are less directly useful for safety analyses because they primarily represent exposure for the time period and time of year when the data were collected.
From page 22...
... 22 Pedestrian and Bicycle Safety Performance Functions program. The CODES program addresses all motor vehicle crash types, including pedestrian and bicycle crashes.
From page 23...
... Literature Review and Survey of Practice 23   2008) , and a similar approach was developed using small grid cell pedestrian analysis zones in Portland, Oregon (Clifton et al.
From page 24...
... 24 Pedestrian and Bicycle Safety Performance Functions General Information Count Information Model Information Model Location Source Type of CountSites Count Period(s) Used for Model Model Output Model Type Charlotte, NC UNC Charlotte (Pulugurtha and Repaka 2008)
From page 25...
... Literature Review and Survey of Practice 25   2.1.5 Methods for Estimating Pedestrian and Bicycle Safety Performance The research team identified several examples of pedestrian and bicycle SPFs developed directly from crash data for application at the local, state, and national levels. Additional examples of agencies that have applied other approaches to estimating pedestrian and bicycle safety performance were also identified, along with several tools developed to prioritize pedestrian and bicycle infrastructure improvements.
From page 26...
... 26 Pedestrian and Bicycle Safety Performance Functions Equation 2-1 is the base model for three-leg signalized intersections in the final form.
From page 27...
... Literature Review and Survey of Practice 27   Nbike is the predicted number of intersection bicycle crashes during the study period, and k is the overdispersion parameter. The models are not specific to any particular intersection type or configuration.
From page 28...
... 28 Pedestrian and Bicycle Safety Performance Functions Effect Category Total Pedestrian Crashes Crashes Involving Pedestrians Crossing and Motorists Going Straight Estimate Std. Error Estimate Std.
From page 29...
... Literature Review and Survey of Practice 29   Effect Category Bicycle Crashes: Total Intersection Crashes Bicycle Crashes: Opposite Direction Intersection Crashes Bicycle Crashes: Angle Intersection Crashes Estimate Std. Error Estimate Std.
From page 30...
... 30 Pedestrian and Bicycle Safety Performance Functions Total 2U −19.530 0.38*
From page 31...
... Literature Review and Survey of Practice 31   Total 2U −25.170 0.960 0.00 3T −4.110*
From page 32...
... 32 Pedestrian and Bicycle Safety Performance Functions Total 3ST −14.744 0.778 0.394 1.214 3SG −11.092 0.575 0.232 1.000 4ST −11.173 0.618 0.188 1.184 4SG −-6.958 0.256 0.227 0.884 FI 3ST −15.567 0.873 0.353 0.939 3SG −10.889 0.551 0.204 1.000 4ST −11.555 0.659 0.157 0.083 4SG −7.834 0.340 0.203 0.702 PDO 3ST −13.646 0.340*
From page 33...
... Literature Review and Survey of Practice 33   To accomplish the objectives of the project, data were collected in four Michigan cities including Ann Arbor, East Lansing, Flint, and Grand Rapids. Data collected included: • Nonmotorized crash data.
From page 34...
... 34 Pedestrian and Bicycle Safety Performance Functions Equations 2-5 and 2-6, Intersection Models exp= .
From page 35...
... Literature Review and Survey of Practice 35   A random effects negative binomial model was developed using 5 years of crash data (2007 to 2011) to predict the number of pedestrian and bicycle crashes combined.
From page 36...
... 36 Pedestrian and Bicycle Safety Performance Functions limited research at the time to demonstrate that it also occurred at an element level (intersection and link) and for specific crash types.
From page 37...
... Literature Review and Survey of Practice 37   The key findings from this model include: 1. Bicycle crash potential per kilometer increases as the link length between major intersections reduces.
From page 38...
... 38 Pedestrian and Bicycle Safety Performance Functions The list of variables considered in the models was as follows: • Manual motor vehicle and bicycle counts for each movement, which were scaled up to AADTs. • Speeds of free-flowing vehicles traveling through the roundabout as they entered and circulated through the roundabout for each approach (collected in the field)
From page 39...
... Literature Review and Survey of Practice 39   benefits of on-road bicycle facilities at traffic signals. This included bicycle lanes on the approach legs of the intersections, bicycle lanes on the departure legs of the intersections, bicycle storage boxes, and wide curb lanes.
From page 40...
... 40 Pedestrian and Bicycle Safety Performance Functions when right-turn drive)
From page 41...
... Literature Review and Survey of Practice 41   The variables collected for this study were extensive but can be grouped under the following five categories: • Detailed signal layout and geometry. • Signal operation (e.g., signal phasing, cycle times, estimated degree of saturation, and coordination)
From page 42...
... 42 Pedestrian and Bicycle Safety Performance Functions The coefficients for motor vehicle and pedestrian volumes in Equation 2-17 are similar, which indicates they are equally important factors. Wider approaches are predicted to have more crashes.
From page 43...
... Literature Review and Survey of Practice 43   for another. Similarly, bicyclists' safety can be compromised by improvements that are made to an intersection to make it safer for motor vehicles and/or pedestrians.
From page 44...
... 44 Pedestrian and Bicycle Safety Performance Functions Having identified pedestrian and bicycle crash-contributing factors, ODOT screened the state and urban nonstate networks separately to prioritize locations where multiple crash-contributing factors were present. The network screening process involved five general steps: 1.
From page 45...
... Literature Review and Survey of Practice 45   prioritize sites based on pedestrian and bicycle crash-contributing factors. ODOT applied the scoring methodology to rank 9,490 segments (0.1 mi each)
From page 46...
... 46 Pedestrian and Bicycle Safety Performance Functions objective to develop a scoring method with weights derived from data analysis, as compared to best judgment or a subjective scoring system. To develop the scoring method, data were collected from 188 random segments and 184 random intersections.
From page 47...
... Literature Review and Survey of Practice 47   Variables Levels Internal Weight Score Traffic direction One-way 3.63 17Two-way 1.00 0 On-street parking Yes 3.81 17No 1.00 0 Posted speed limit (mph) < =25 1.00 0 30 1.28 6 35 1.64 8 > 35 2.70 12 Presence of TWLTL Yes 2.92 14No 1.00 0 Total population density (per square mile)
From page 48...
... 48 Pedestrian and Bicycle Safety Performance Functions Variables Levels Internal Weight Score Bikes per day (STRAVA) < =200 1.00 0 201–800 1.50 15 > 800 2.48 25 Major AADT (2014)
From page 49...
... Literature Review and Survey of Practice 49   segment, and the star ratings (1 through 5) are assigned for specific bands of the road safety score.
From page 50...
... 50 Pedestrian and Bicycle Safety Performance Functions Road User Crash Type Roadway Feature Coded into ViDA Pedestrians Along the roadway Sidewalk Curvature Quality of curve Sight distance Lane width Delineation Grade Road condition Speed management, traffic calming Vehicle parking Shoulder rumble strips Street lighting School zone warning Crossing an intersection leg Number of lanes Median type Pedestrian crossing Pedestrian crossing quality Intersection type Intersection quality Pedestrian fencing Skid resistance, grip Street lighting Sight distance Vehicle parking Speed management, traffic calming School zone warning Bicyclists Run-off Lane width Curvature Quality of curve Delineation Street lighting Road condition Grade Skid resistance, grip Along the roadway Facilities for bicycles Curvature Quality of curve Sight distance Lane width Delineation Grade Road condition Speed management, traffic calming Shoulder rumble strips Vehicle parking Skid resistance Street lighting Crossing the major/minor road Intersection type Intersection quality Property access points Skid resistance, grip Facilities for bicycles Street lighting Sight distance Intersection channelization Speed management, traffic calming Pedestrian crossing Table 20. Roadway features that impact the likelihood of pedestrian and bicycle crash types in usRAP.
From page 51...
... Literature Review and Survey of Practice 51   be compared. That is, a segment with a lower star rating may be expected to have fewer fatalities than a segment with a higher star rating simply because fewer people are using the facility.
From page 52...
... 52 Pedestrian and Bicycle Safety Performance Functions SWOV used hierarchical, multiple regression models to investigate the relationship between cycling infrastructure characteristics and bicycle crashes (Wijlhuizen, Dijkstra, and van Petegem 2014)
From page 53...
... Literature Review and Survey of Practice 53   priority for undergoing pedestrian and bicycle safety improvements. The Ped and Bike ISI scores are an evaluation of each approach leg of an intersection rather than the intersection as a whole.
From page 54...
... 54 Pedestrian and Bicycle Safety Performance Functions Ped ISI = 2.372 – 1.867SIGNAL – 1.807STOP + 0.335THRULANES + 0.018SPEED + 0.006(MAINADT×SIGNAL) + 0.238COMM SIGNAL Signal-controlled crossing 0 = no1 = yes STOP Stop-controlled crossing 0 = no1 = yes THRULANES Number of through lanes on street being crossed (both directions)
From page 55...
... Literature Review and Survey of Practice 55   2.1.5.11 ActiveTrans Priority Tool Lagerwey et al.
From page 56...
... 56 Pedestrian and Bicycle Safety Performance Functions HSM-approved CMFs; rather, Part D of HSM2 will provide information on how to select and apply CMFs and direct users to the CMF Clearinghouse to find high-quality CMFs. The following subsections summarize recently developed CMFs the research team considered for use as adjustment factors with the pedestrian and bicycle SPFs developed as part of this research.
From page 57...
... Literature Review and Survey of Practice 57   2.1.6.2 Install Pedestrian Hybrid Beacons (PHBs) Zegeer et al.
From page 58...
... 58 Pedestrian and Bicycle Safety Performance Functions mobility. PEDSAFE includes 67 engineering, education, and enforcement countermeasures in the toolkit.
From page 59...
... Literature Review and Survey of Practice 59   Countermeasure Estimated Crash Reduction Central hatching 10%–25% Pedestrian crossing – unsignalized 25%–40% Pedestrian fencing 25%–40% School zones 10%–25% Sight distance (obstruction removal) 25%–40% Skid resistance 25%–40% Pedestrian footpath 40%–60% Pedestrian refuge island 25%–40% Regulate roadside commercial activity 10%–25% Parking improvements 10%–25% Intersection – signalize 25%–40% Shoulder sealing 25%–40% Speed management 25%–40% Street lighting 10%–25% Pedestrian crossing – signalized 25%–40% Traffic calming 25%–40% Restrict/combine direct access points 25%–40% Pedestrian crossing – grade separation 60% or more Service road 25%–40% Table 27.
From page 60...
... 60 Pedestrian and Bicycle Safety Performance Functions 2.2 Survey of Practice The research team conducted a survey of transportation agencies, practitioners, and researchers to learn about their experiences related to the development and use of pedestrian and bicycle SPFs. The research team also contacted select agencies to gather information about their pedestrian and bicycle count programs, inventory datasets, and crash datasets.
From page 61...
... Literature Review and Survey of Practice 61   Select international pedestrian and bicycle safety experts: • Chairs of the following TRB standing committees, sections, and task forces for distribution to committee members and friends: – Standing Committee on Transportation Issues in Major Cities (ABE30)
From page 62...
... 62 Pedestrian and Bicycle Safety Performance Functions Other responses: • We conducted a bike/pedestrian network screening to identify crash hot spot locations or roadways and intersections with worse safety performance than comparable facilities based on crash type, history, and crash rate. We analyzed the level of traffic stress for cyclists for all roads in our Transportation Planning Organization (TPO)
From page 63...
... Literature Review and Survey of Practice 63   Combination responses: • Pedestrian data collection is episodic, not routine. When done, we use manual and video.
From page 64...
... 64 Pedestrian and Bicycle Safety Performance Functions inventory but has video log systems from which pedestrian/bicycle infrastructure data can be collected through image processing or manual collections. However, no such effort has been carried out, due to lack of staff time, funding, or video processing expertise.
From page 65...
... Literature Review and Survey of Practice 65   • Strava. • Currently, we rely on our local planning partners to do the counts as part of their planning process.
From page 66...
... 66 Pedestrian and Bicycle Safety Performance Functions • If we have any issues at all, it'll be related to the fact that Oregon is a self-reporting state. Overall, our crash data is very good, where it exists.
From page 67...
... Literature Review and Survey of Practice 67   What steps have been taken to overcome these barriers to collecting pedestrian safety performance data? (Please specify if you have access to any internal or external reports that provide best practices to overcome these challenges.)
From page 68...
... 68 Pedestrian and Bicycle Safety Performance Functions • Do not know of any, but there may be steps taken by others in the agency. • We are discussing it but no concrete plans yet.
From page 69...
... Literature Review and Survey of Practice 69   • Have investigated some methods to collect counts but have not implemented or tried any technologies. • Reliance on Regional Planning and DOT data.
From page 70...
... 70 Pedestrian and Bicycle Safety Performance Functions reports. There are also only two staff members that focus on Bicycle and Pedestrian efforts.
From page 71...
... Literature Review and Survey of Practice 71   • Some minimum level of effort has been completed. Using usRAP to document pedestrian activity along the functional classified routes.
From page 72...
... 72 Pedestrian and Bicycle Safety Performance Functions Other responses: • We have good data but need additional counts for more accurate crash * rate*
From page 73...
... Literature Review and Survey of Practice 73   • We devote staff time to reading crash report narratives and confirming that a cyclist was involved in the crash, the severity of the crash, the geolocation of the crash, and whether or not the crash occurred on private property. We have developed a ‘how to' document for cleaning the data.
From page 74...
... 74 Pedestrian and Bicycle Safety Performance Functions • SDOT is ramping up exposure data collection for bicyclists throughout the city. Previous data was ad hoc and has been found to be lacking in our desires moving forward, so we have to develop a new standard for data before accuracy can be confirmed.
From page 75...
... Literature Review and Survey of Practice 75   • We have hired additional staff, and we are increasing our current budget to purchase more Eco Counters (permanent counter locations) and maintain our existing temporary counter program that utilizes Trafx counters (temporary counters are deployed at various locations across the region for approximately 2-week periods)
From page 76...
... 76 Pedestrian and Bicycle Safety Performance Functions • We devote staff time to update infrastructure databases, but it is a significant undertaking. We intend to update databases annually moving forward to minimize the time required for each update.
From page 77...
... Literature Review and Survey of Practice 77   Other responses: • Safety Analyst was used and has been discontinued. • We have developed in-house tools for network screening using SPFs on segments.
From page 78...
... 78 Pedestrian and Bicycle Safety Performance Functions Predictive Method for Urban and Suburban Arterials 1 (Low)
From page 79...
... Literature Review and Survey of Practice 79   Bicycles: Predictive Method for Rural TwoLane, Two-Way Roads 1 (Low)
From page 80...
... 80 Pedestrian and Bicycle Safety Performance Functions Six-lane arterials 11.8% (4)
From page 81...
... Literature Review and Survey of Practice 81   • Presence of marked crosswalk and/or beacons. • Any measure that is used to enhance crossing would be most important (but would like to see all the ones above)
From page 82...
... 82 Pedestrian and Bicycle Safety Performance Functions Roadway Segments: Presence of dedicated bicycle lane 85.3% (29) Presence of protected/separated bicycle lane 76.5% (26)
From page 83...
... Literature Review and Survey of Practice 83   • Lighting, signal head info, and complexity of intersection (number of potential conflicts, number of potential movements, etc.)
From page 84...
... 84 Pedestrian and Bicycle Safety Performance Functions Other responses: • All of our pedestrian counts are done through individual projects and are not done on a regular basis. • At bottlenecks.
From page 85...
... Literature Review and Survey of Practice 85   7. For what type(s)
From page 86...
... 86 Pedestrian and Bicycle Safety Performance Functions 10. If any option in Question D9 is selected, on average what are the durations of these bicycle counts?
From page 87...
... Literature Review and Survey of Practice 87   13.1 If YES to Question D13, please describe the types of surrogate volume data that are collected for pedestrian activities. Response: 1 2 Vehicular traffic volumes Unofficial counts done with the Jamar board Known Estimated mode split based on state or national averages N/A Known Estimated mode split calibrated to individual jurisdictions N/A Sometimes Counts obtained for a subset of the population (e.g., ride tracking app)
From page 88...
... 88 Pedestrian and Bicycle Safety Performance Functions 14.2 For what type(s) of roadway segments and intersections have these surrogate measures been estimated for bicycle activities?
From page 89...
... Literature Review and Survey of Practice 89   17. Does your agency have access to any nontraditional data sources that might indicate frequency of crashes involving pedestrians and/or bicycles (e.g., police reports or hospital records)
From page 90...
... 90 Pedestrian and Bicycle Safety Performance Functions • Almost all proposed CMFs were strongly desired for both pedestrian and bicycle crashes at both intersections and roadway segments. The top responses (> 64% approval)
From page 91...
... Literature Review and Survey of Practice 91   coming years. Roughly 380 sites are regular count locations, which the Public Works Department counts in a 3- to 4-year cycle.
From page 92...
... 92 Pedestrian and Bicycle Safety Performance Functions Vehicle annual average daily traffic (AADT) is recorded but may be in computer-aided design (CAD)
From page 93...
... Literature Review and Survey of Practice 93   2.2.2.5 Location/Agency: Delaware Valley Regional Planning Commission (DVRPC) , Philadelphia, Pennsylvania The DVRPC is the federally designated Metropolitan Planning Organization (MPO)
From page 94...
... 94 Pedestrian and Bicycle Safety Performance Functions Oregon DOT conducted a study, Risk Factors for Pedestrian and Bicycle Crashes (Monsere et al.
From page 95...
... Literature Review and Survey of Practice 95   is by developing standard training materials and count forms for volunteers. Standard reporting sheets are also a good practice to aid the development of a common way to store data.
From page 96...
... 96 Pedestrian and Bicycle Safety Performance Functions but some models were developed for roadway segments. In some instances, SPFs were developed for specific crash types such as pedestrians and bicyclists crossing and motorists traveling straight through the intersection or pedestrians and bicyclists crossing and motorists making a left turn.
From page 97...
... Literature Review and Survey of Practice 97   Category Contributing Factor Pedestrian Bicyclist Roadway Segment Intersection Roadway geometric and operational characteristics Number of lanes Lane width Shoulder width Presence of bicycle lanes Presence of on-street parking Presence of median Vertical grade/slope Horizontal curve Quality of curve Presence of shared-use paths Sidewalk width Presence of bus stops Number of driveways Presence of midblock crossing Presence of lighting Delineation Shoulder rumble strips Sight distance Road condition Posted/operating speed Speed management/traffic calming Distance to closest marked crosswalk or intersection Distance to nearest traffic signal Functional class One-way versus two-way traffic Number of through lanes being crossed Number of left-turn lanes Number of right-turn lanes Presence of marked crosswalk Type of traffic control Pedestrian crossing quality Pedestrian fencing Skid resistance/grip Presence of pedestrian-activated flashers or beacons AADT Pedestrian volume Bicycle volume Number of left- and right-turning vehicles Percent heavy vehicles Pedestrian delay Land use Land use (commercial, industrial, institutional, residential) Block size Presence of school zone Presence of alcohol sales establishments Urban/rural Demographics Age Population density Household size Mean household income Ethnicity Single-family residential Vehicle numbers in housing units Table 29.
From page 98...
... 98 Pedestrian and Bicycle Safety Performance Functions Category Treatment/Countermeasure Along the roadway • Sidewalks, walkways, and paved shoulders • Pedestrian fencing • Regulated roadside commercial activity • Shoulder sealing • Restrict/combine direct access points At crossing locations • Curb ramps • Marked crosswalks and enhancements • Curb extensions • Crossing islands • Raised pedestrian crossing • Lighting and illumination • Parking restrictions • Pedestrian overpass/underpass • Automated pedestrian detection • Leading pedestrian interval • Advance yield/stop lines • Central hatching • School zones Transit • Transit stop improvements • Access to transit • Bus bulb-outs Roadway design • Bicycle lanes • Lane narrowing • Lane reduction (road diet) • Driveway improvements • Raised medians • One-way/two-way street conversions • Improved right-turn slip-lane design • Skid resistance • Speed management Intersection design • Modified T-intersections • Intersection median barriers • Curb radius reduction • Modified skewed intersections Signals and signs • Traffic signals • Pedestrian signals • Pedestrian signal timing • Traffic signal enhancements • Right-turn-on-red restrictions • Advanced stop lines at traffic signals • Left-turn phasing • Push buttons and signal timing • Pedestrian hybrid beacon (PHB)
From page 99...
... Literature Review and Survey of Practice 99   Category Treatment/Countermeasure Shared roadway • Roadway surface improvements • Lighting improvements • Parking treatments • Median/crossing island • Driveway improvements • Lane reductions (road diet) • Lane narrowing • Street track treatments • Pedestrian fencing • Regulate roadside commercial activity • Shoulder sealing • Speed management • Road surface rehabilitation • Restrict/combine direct access points On-road bike facilities • Bike lanes • Wide curb lanes • Paved shoulders • Shared bus-bike lanes • Contraflow bike lanes • Separated bike lanes Intersection treatments • Curb radius reduction • Intersection markings • Turn restrictions • Crosshatching • Sight distance Markings, signs, and signals • Optimizing signal timing for bicyclists • Bike-activated signal detection • Sign improvements for bicyclists • Pavement marking improvements • School zone improvements • Rectangular rapid flashing beacons (RRFBs)

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