Washington College GIS has formed a partnership with the Maryland State Police, with the assistance of data provided by the State Highway Administration, to analyze traffic accidents statewide through density mapping. This is performed by collecting all traffic accident data for the entire state of Maryland, and dividing this data into the 22 Maryland State Police Barrack Districts. The study area for each barrack includes crashes on interstates, US highways and state highways, but excludes municipalities, where other police agencies have jurisdiction. Within barrack boundaries the data is again separated by all accidents, impaired accidents, and aggressive driving accidents. For the purposes of data classification an accident is considered impaired if the driver was found to be under the influence of drugs, alcohol or a combination of the two. Accidents with aggressive driving are defined by the cause of the accident which is designated in the police report.
Once the data is divided appropriately maps are created for each barrack which show all accidents, impaired driving accidents, and aggressive driving accidents. These maps are then used to create Hot Spot maps for each of the three categories, which visually demonstrate areas of statistically high crash density. Other maps are created that focus on each hotspot individually in order to show exact locations of crash occurrence. Further analysis is then performed which breaks crashes down by time of day, and by day of the week.
Such an analysis allows the State Police to make best use of their limited resource by deploying them to areas of greatest need, as designated by the hot spots. Further use of the day and time data allows for further manipulation of resource allotment and use, while the classification of crashes into impaired and aggressive enables use of this data by tasks forces, such as the Governor’s Task Force on Drunk Driving to target enforcement and to educate law enforcement on areas of high concentrations of these types of accidents.