Spatial database for intersections.

Intersections are one of 10 areas of emphasis listed in Kentucky’s most recent Strategic Highway Safety Plan (SHSP). Crashes that occur at intersections represent approximately 25% of all collisions in Kentucky (Kentucky Traffic Collision Facts). Representatives from the Kentucky Transportation Cabinet (KYTC) have expressed that a maintainable intersection database is needed to reduce the number of crashes. Because state transportation agencies have become increasingly reliant on spatially explicit data, a spatially-enabled intersection database would benefit many areas of transportation. In 2003, the Kentucky Transportation Center (KTC) conducted a research study on vehicle crashes at intersections. The dataset produced during that research has since become the primary database used by the Cabinet for intersection safety analysis and prioritization ranking. Unfortunately, this database was created to analyse safety over a fixed time period and is now out-of-date. The objective of this research study is to develop a comprehensive database that inventories all intersections in the state of Kentucky-- one that includes the points where all state-maintained and locally maintained roadways intersect. The major impetus for creating this database is to equip KYTC with the knowledge it needs to prioritize intersections for safety improvements. To that end, it is important to categorize intersections so they can be compared with one another. Comparisons must focus on similarly functioning sites instead of generating one priority list that ignores important geometric and operational differences. The database that resulted from this study can be updated using an automated process. It can identify any changes to roadway geometry that would alter the attributes of intersections. In addition to point features used for locating intersections, this database accounts for each intersection’s zone of influence. This encompasses the area around intersection points at which crashes are assumed to be attributable to the intersection. (Author/publisher)