1 Safety Data in a GIS Environment: New Tools for the Four Es Sponsored by the Iowa Department of Transportation Office of Transportation Safety Reginald R. Souleyrette Tim R. Strauss Iowa State University Prepared for the 24th International Forum on Traffic Records and Highway Information Systems July 26-28, 1998 Minneapolis, Minnesota

2 Why Crash Analysis Systems? >100 persons killed/day (>37,000 in 1996) 8.8 million crashes per year in USA 2.3 million injuries vast amount of uncoordinated data powerful/low cost computing potentially huge B/C source: NHTSA 1997

3 Past/present ALAS (PC-ALAS) PC-based system User-friendly interface, easy to learn About 700,000 crashes over 10 years Provides easy access to data Several Uses: –obtain accident statistics by time and location –query database by accident/driver characteristics –generate reports on-screen, to a file, to the printer

4 Current Difficulties Node numbers must be identified from tables or paper maps Difficult to analyze patterns Does not readily support integration of additional data Hard to identify crash “hot spots” and to analyze causes and countermeasures

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6 Past/present ALAS

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12 GIS-ALAS Project Goals Develop geographic/map-based ALAS Use Power of GIS Portable, accessible, windows based Free users from node maps statewide coverage supports highway safety analysis facilitate integration with other data

13 Software Selection GIS World list –distribution –development language –vendor stability short list (pre-Geomedia) –ESRI (ArcView, Arcview Publisher, ArcExplorer, MapObjects) –Mapinfo –Caliper (Maptitude)

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15 Software Selection (cont.) ESRI chosen –ISU site license (low cost development) –dynamic segmentation –network analysis –tech. Support (ISU GIS Facility) –FHWA platform –web application (MapObjects, Internet Mapper) –ArcExplorer, ArcPublisher May migrate later

16 Crash Locations text Text - node ID, x, y MapBasic interpolation program MapInfo Crash Locations CAD node file MGE (unit conversion) Text - node ID, lat, long MapInfo Node Locations Paper crash records DB2 - ID - from node - to node - distance - crash information MIF ArcView Crash Locations x’ y’

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18 DB2 - ID - location information - A (crash) records - B (driver 1) record - B (driver 2) record - … - C (1st 3 injuries) record - C (2nd 3 injuries) record -... Crash Information Paper crash records MapBasic defines 3 tables A, B and C MapInfo text MIF ArcView Crash Information (for ArcView-ALAS) text fortran ABBBC ArcView Crash Information (for Explorer-ALAS)

19 Background Data IDMS Base Records (DOT) - ADT - pavement type - lane width -... CAD Roads (DOT) - State - County - Local Text file - vertices - information MapInfo/MapBasic aggregate to county level MIFArcView CAD Hydrology (DOT) DXF Rail (BTS) BTS preprocessor

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21 Avenue Scripts

22 PC ALAS GIS ALAS

23 Usability Study Evaluate capabilities Assess documentation Identify bugs and problems in data Identify differences between users' and designers' perceptions Report user difficulties Report on success of revision

24 Logical Query

25 Spatial Query

26 Visual Display of Crash Frequencies

27 Possible error Error Checking

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32 Animal-related Crashes

33 Applications: Collision Diagram Software Interface

34 Emergency Response Applications Emergency response areas Nearest facility/shortest path to crash Impact of “Avenue of the Saints” on emergency response CODES - linking crash and hospital records

35 EMS Response Areas

36 Aerial Photo Integration

37 Fire Districts Response Changes

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39 Software enhancements Fire Service Application/Avenue of the Saints Model integration Training Ongoing Efforts

40 x Nearest node 2nd nearest node in opposite direction 150 ft N W N W from 3405, to 3412, 150 ft.

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