HSM Applications to Multilane Rural Highways and Urban Suburban Streets Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – Prediction of Safety Performance for Urban/Suburban Multilane Highway and Comparison to Substantive Safety Performance - Session #6 Instructor: Session #6– Exercise II –– Prediction of Safety Peformance for suburban/urban Multilane Highway and Comparison to Substantive Safety Performance Photo is IL 64 case study in “before” condition of 4lanes with double yellow separating the opposing traffic lanes and 8 foot gravel shoulders Session 5 –Exercise I

Apply Urban/Suburban Multilane Crash Prediction model Exercise II – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Learning Outcomes: Apply Urban/Suburban Multilane Crash Prediction model Compare predicted safety performance to actual safety performance Instructor: Please review the Learning Objectives for Session #07 Exercise II Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn IL 64, DuPage County, Illinois: IL Route 64, an east-west state highway initiates at Lake Michigan in the City of Chicago and terminates at the Mississippi River at the west border of Illinois. In DuPage County, 1987 population of 780,000, IL Route 64 is known as North Avenue traversing the cities of Elmhurst and Villa Park and through rural unincorporated areas west to St. Charles Illinois in Kane County. IL Route 64 was improved to 4 lanes in the 1960’s throughout this length with intersection improvements at major crossroads such as other state routes and county routes consisting of left turn lanes and traffic signal control during the 1960’s and 1970’s. Instructor: IL 64 Geometric Plan information Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Instructor: IL 64 location map Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Geometric Information: Cross-Section: Four 12-foot wide lanes with double yellow centerline dividing the opposing directions of travel (Undivided) 8 foot wide aggregate shoulders 12 foot wide left turn lanes at all major intersections No left turn lanes at minor street intersections nor at commercial driveways Parking prohibited No highway illumination other than some minor intersection lighting by local municipalities and the County Highway Department Instructor: IL 64 Geometric Plan information Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Study Section: Length of Section = 0.97 miles ADT = 37,000 vpd No Horizontal Curves; 2.8% vertical curve west of Shopping Center for 0.35 mi Driveways: Minor Residential driveways 7 Minor commercial driveways (< 50 parking spaces) 7 Major commercial driveways (> 50 parking spaces) 11 Total # of Driveways 25 Instructor: Let’s keep the data the same as in Slide 3-6 --- Please note that one additional major driveway has been added to the driveway total – a new shared driveway to a McDonalds and a Portiollo’s and the Portiollo’s traffic is nearly double that of the McDonalds. Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Study Section: Number of Unsignalized Intersections with left turn lanes 0 Number of Unsignalized Intersections without turn lanes 9 Trees and Power poles 18.0 feet from edge of pavement with spacing of 160 foot apart, one side Signalized Intersections: Bloomingdale Road 16,100 AADT Shopping Center (north and south) 2,400 AADT Main Street-Glen Ellyn 16,700 AADT Instructor: IL 64 Geometric Plan information Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Unsignalized Intersections: Mildred 700 AADT Virginia 700 AADT Bernice 700 AADT Western 700 AADT Pearl 1,500 AADT Diane 700 AADT Evergreen 700 AADT Amy 700 AADT Newton 700 AADT Signalized Intersections: Bloomingdale Road 16,100 AADT Shopping Center (north and south) 2,400 AADT Main Street-Glen Ellyn 16,700 AADT Instructor: North Avenue IL 64 intersection information for the mile segment from Bloomingdale Road on the west to Glen Ellyn Road on the east Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Study Section: Crash data for 1986, 1987, 1988 – 3 years Total Injury Crashes Crashes Day Night Rdwy Segment 84 26 57 27 SubTotal: 84 26 57 27 Instructor: “Before” crash data from IDOT Safety Section from the Phase I study for North Avenue IL 64 project Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Crash data for 1986, 1987, 1988 – 3 years Intersections: Total Injury Day Night Mildred 9 2 6 3 Virginia 12 3 9 3 Bernice 16 3 11 5 Western 11 4 7 4 Pearl 22 6 16 6 Diane 16 5 11 5 Evergreen 11 4 7 4 Amy 7 4 4 3 Newton 12 5 8 4 Bloomingdale Rd 170 68 122 48 Shopping Center 18 5 13 5 Main St-Glen Ellyn 146 45 100 46 Totals: 450 154 314 136 Instructor: “Before” crash data from IDOT Safety Section from the Phase I study for North Avenue IL 64 project Total Crashes for the 12 intersections = 450 crashes Injury Crashes for the 12 intersections = 154 crashes Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Study Section: Crash data for 1986, 1987, 1988 – 3 years Total Injury Crashes Crashes Day Night Rdwy Segment 84 26 57 27 12 Intersections 450 154 314 136 Totals: 534 180 371 163 Instructor: “Before” crash data from IDOT Safety Section from the Phase I study for North Avenue IL 64 project Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Predict the Crash Frequency Performance for the segment using the Suburban Multilane Undivided model (4U) for the following: Base Model Multiple Vehicle Non-Driveway Base Model Single Vehicle Non-Driveway Driveway Related Crashes CMF’s for Parking, Roadside Objects, and Lighting Predicted Crashes with CMF’s Applied Pedestrian Crashes Bicycle Crashes Total Predicted Crashes for Segment Instructor: go thru Task #1 and the eight (8) sub tasks – subtask a through h - in Task 1 Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn From the Crash Frequency Prediction analysis, perform the following: Is the actual Crash Frequency Performance for the geometrics for IL 64 less than the Predicted Crash Frequency Performance? Instructor: go thru task 2 And the crucial aspect is the substantive safety performance (actual crashes per year) safer than the predicted number of crashes or not; if not, then the safety performance needs improvement Instructor should hold on this slide while the workshop participants do tasks 1 and 2 – should take about 20 minutes Substantive Safety Performance = ? Predicted Safety Performance = ? Safer than Predicted YES/NO? Session 5 –Exercise I

Nrs = (Nbr + Npedr + Nbiker) Cr Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Procedure for safety prediction for a roadway segment: Combine base models, CMFs, and calibration factor Nrs = (Nbr + Npedr + Nbiker) Cr Nbr = Nspf rs (CMF1r x CMF2r x … CMFnr) Instructor: from Chapter 12 of the Draft Highway Safety Manual on Roadway Segments. Remind participants of the prediction models and associated variables. Nspf rs = Nbrmv + Nbrsv + Nbrdwy Use Worksheet Exercise II Session 5 –Exercise I

Nbr = Nspf rs(CMF1r x CMF2r x .. CMFnr) Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Nbr = Nspf rs(CMF1r x CMF2r x .. CMFnr) Where: Nbr = Predicted number of total roadway segment crashes per year with CMFs applied Nspf rs = Nbrmv + Nbrsv + Nbrdwy = 19.2 crashes/yr CMF’s = Crash Modification Factors for roadway segments (Parking, Roadside Objects, and Lighting) Instructor: from Chapter 12 of the Draft Highway Safety Manual Now that we’ve calculated Nspf rs we can move on and calculate Nbr which appllies the CMFs to the predicted crash frequency for base conditions. Session 5 –Exercise I

Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn From the Crash Frequency Prediction analysis, perform the following: Is the actual Crash Frequency performance for the geometrics for IL 64 (Driveways, parking, and lighting) less than the Predicted Crash Frequency? Substantive Safety Performance = Instructor: and the answer to “safer than predicted is…..” NO, it is not safer and it is not safer by a factor greater than 3 Please keep in mind that the crashes for the 9 side roads are included in the before segment crashes ____crashes per year Predicted Crash Frequency = ____ crashes per year Less than Predicted ? YES/NO Session 5 –Exercise I

Applied Rural Multilane Crash Prediction model Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Exercise II – IL 64 North Ave from Bloomingdale Rd to Main St – Glen Ellyn Learning Outcomes: Applied Rural Multilane Crash Prediction model Compared predicted safety performance to actual safety performance Instructor: please review Learning Objectives for Session #7 – Exercise II Session 5 –Exercise I

Questions and Discussion Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop April 2009 Questions and Discussion Session 5 –Exercise I