Crash Mapping Notes

1. Data is provided by the New York State Department of Transportation based on MV-104 forms filed by police precincts.

2. Maps are created using Microsoft MapPoint North America 2004.

3. All crash locations are mapped to either intersections or midpoints between those intersections.

4. Crash locations that appear to not be on intersections or at the midpoint between two intersections should only be considered valid in the following case: if the surrounding crashes seem to shifted off of the actual intersections in a similar manner, there may be a small disagreement between the location of the intersection and the actual location due to errors in surveying or coordinate translation.

5. If the discrepancy cannot be explained by surveying/translation errors, the crashes have usually been described as the midpoint between two non-adjacent intersections. Since midpoint crashes are mapped according to the average of the locations of two intersections, crashes described as the midpoint between two non-adjacent intersections will produce an extraneous data point and should be ignored, as the location of the crash is not precise.

6. In certain parts of the city, crash records are not included in our data set.  This includes Central Park, Prospect Park and Battery Park City, among other locations including other large parks.

7. If you are working on traffic calming and traffic safety issues in your NYC community and have questions regarding the crash data in your neighborhood, please e-mail them to info@transalt.org.