1. Creating and Using an Intersection Inventory
Sharing the WYDOT Experience

2. WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting
My Main Points
An Intersection Inventory is a valuable safety asset
Creating one is challenging, but worth it
The time is right to pursue
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

3. The “Intersection Equation”
+ ≠ −
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

4. An Intersection Inventory - Is…
A defined database structure
List of intersections
And their attributes
Related legs
Linkable
By geo-location, unique ID
With crash data
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

5. An Intersection Inventory – Why?
Consolidates useful data
Can assign crashes
Facilitates Analysis
Selecting the intersection (crashes)
HSM Predictive modeling
Relative ranking
Comparison with “like” intersections
Enables associated tools
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

6. Exponential References
I 25 Business
US 85
South Greeley Highway
I 25 Business
WY 212
W College Dr
WY 212
E College Dr
US 85
South Greeley Highway
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

7. Creating an Intersection Inventory – How?
Define data model
Populate the list
Add in the attributes
Handling the gotcha’s
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

8. LRS Processing – Before
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

9. WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting
LRS Processing - After
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

10. Handling Special Cases
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

11. WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting
Even More Complicated
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

12. Introducing Our Intersection
Located in Casper
Major Route
WY 258 / WYOMING BLVD
Direction: N/S
Highway
Minor Route
E 2ND ST
Direction: E/W
Signalized: Yes
Number of legs: 4
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

13. Intersection Inventory – In Use
Categorize (“like” intersections)
Assign crashes
Analyze
View/Edit
Report
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

14. WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting
Assign Crashes
Simple algorithm: If within 250 feet of the intersection, then assign to the nearest intersection.
(500 feet on major route of a rural intersection)
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

15. Analyze – Relative Ranking
Signalized 4-leg On-System
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

16. WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting
Analyze – Top Level
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

17. Analyze – Types of Crashes
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

18. Analyze – Data Presentation
Intersection Collision Diagram
A graphical representation of the crash types that on each leg (by quadrant).
Does not indicate location.
South-
bound
West-
bound
East-
bound
North-
bound
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

19. Analyze – Crash Locations
Showing the location (as entered by the officer) of each crash assigned to the intersection.
Color indicates injury severity
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

20. View/Edit the Intersection Data
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

21. And the Intersection Legs…
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

22. Intersection Inventory – The Time is Right!
ARNOLD
GIS capability
Progress on Segments
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

23. Questions? For off-line follow up, feel free to contact
– State HW Safety Engineer
– Consultant to WYDOT

24. WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting
Take-Away Points
An Intersection Inventory is a valuable safety asset
Creating one is challenging, but worth it
The time is right to pursue
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

26. Backup Slides

27. Maintaining the Intersection Inventory
Periodic processing of the LRS
Flag changes (new/modified/removed)
Updating attributes
Populating additional attributes
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

28. MIRE FDE (non-local paved)
Unique Junction Identifier (120).
Location Identifier for Road 1 Crossing Point (122).
Location Identifier for Road 2 Crossing Point (123).
Intersection/Junction Geometry (126).
Intersection/Junction Traffic Control (131).
AADT (79)
for Each Intersecting Road
AADT Year (80)
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

29. Attributes - Intersection
INTERSECTION_ID
AREA_TYPE_CODE
CITY_ID
COUNTY_ID
FACILITY_TYPE
GEOMETRY
INTERSECTION_LIGHTING_ID
INTERSECTION_NAMES
INTERSECTION_ROUTES
JUNCTION_GEOMETRY_TYPE_ID
JUNCTION_NUMBER_OF_LEGS
JUNCTION_OFFSET_TYPE
JUNCTION_TRAFFIC_CONTROL
JUNCTION_TYPE_ID
MAJOR_ROUTE_DIRECTION
MAJOR_ROUTE_ID
MAJOR_ROUTE_NAME
MAJOR_ROUTE_RM
MINOR_ROUTE_DIRECTION
MINOR_ROUTE_ID
MINOR_ROUTE_NAME
MINOR_ROUTE_RM
RELATED_INTERCHANGE
ACTIVE
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

30. WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting
Attributes - Legs
INTERSECTION_ID
INTERSECTION_LEG_ID
ROUTE_ID
ROUTE_NAME
FROM_RM
TO_RM
LEG_AZIMUTH
LEG_DIRECTION
TWOWAY_VS_ONEWAY
AADT
AADT_YR
LEG_WIDTH
ENTERING_SIGHT_DISTANCE_L
ENTERING_SIGHT_DISTANCE_R
ACCELERATION_LANE_LENGTH
LTURN_OFFSET
LTURN_OFFSET_DISTANCE
LTURN_OFFSET_TYPE
LTURN_PHASING
MEDIAN
MEDIAN_EXISTS
NUMBER_ENTERING_LANES
NUMBER_LEFT_TURN_LANES
NUMBER_RIGHT_TURN_LANES
NUMBER_THROUGH_LANES
RIGHT_TURN_CHANNELIZATION
SAFETY_FEATURE_OPTIONS
SPEED_LIMIT
TRAFFIC_CONTROL
TURN_PROHIBITIONS
TYPE_OF_DETECTION
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting

31. Analysis – Direction of Force
WYDOT's Intersection Inventory - Joe McCarthy, JDI Consulting