Data Item |
Baltimore, MD |
Charlotte, NC |
El Cajon, CA |
Howard County, MD |
Crash data |
Maryland CODES data from National Study Center for Trauma and MSUniversity of Maryland-Baltimore |
Charlotte Department of Transportation (DOT) |
California Highway Patrol Crash Database (SWITRS) |
Maryland CODES data from National Study Center for Trauma and MSUniversity of Maryland-Baltimore |
Intersection traffic counts |
From Baltimore Traffic Management Centers (TMCs), Maryland State Highway Administration counts, MPO (BMC) counts, and vendor loop data |
Database of total intersection entering volumes, hardcopied TMCs, midblock counts, and approach volumes on signal plans |
El Cajon turning movement counts and permanent station countsLink volumes from the area MPO (SANDAG) |
Howard County TMCs and midblock ADTsMaryland State Highway Administration (MDSHA) TMCs and midblock ADTs |
Number of approach lanes, medians, turn lanes |
Aerial photos from Baltimore GIS data |
Signalized: Most are from detailed signal plans, a few from aerial photographsUnsignalized: Estimated from aerial photos |
Signalized: Signal plansUnsignalized: Aerial photos, signal warranting study reports, and drawings of adjacent intersections |
Signalized: Howard County and MDSHA signal plans, aerial photos |
Intersection "change" data |
Baltimore historical timing sheets |
No signal timing change data available. |
El Cajon historical signal timing sheets |
From historical signal plans and log maintained by Howard County staff |
Traffic signal phasing data |
Baltimore printouts of current signal timing |
Charlotte signal timing system |
El Cajon printouts of current signal timing |
Howard County and MDSHA signal plans |
LEDs and backplates |
No data available |
From signal drawings |
Used by El Cajon, but no formal installation dates were available |
From log maintained by Howard County staff |
RLC installation date |
City of Baltimore Traffic Engineering Division |
Charlotte DOT |
El Cajon Traffic Engineering Division and Police |
Howard County staff |
RLC signing |
City of Baltimore policy |
Charlotte DOT policy |
El Cajon Traffic Engineering Division policy |
Howard County policy |
RLC ticket protocol |
City of Baltimore Traffic Engineering Division |
Charlotte DOT |
El Cajon Traffic Engineering Division |
Howard County staff |
Data item |
Montgomery County, MD |
San Diego, CA |
San Francisco, CA |
Crash data |
Maryland CODES data from National Study Center for Trauma and MSUniversity of Maryland-Baltimore |
California Highway Patrol Crash Database (SWITRS) |
California Highway Patrol Crash Database (SWITRS) |
Intersection traffic counts |
Montgomery County ADTs and TMCs |
San Diego machine counts and turning movement counts |
San Francisco ADT files, hardcopied turning movement counts and approach countsState-maintained ADTs |
Number of approach lanes, median presence, presence of turn lanes |
Signalized: Signal plans supplemented with aerial photosUnsignalized: Intersection drawings on TMCs |
Signalized: Signal plans (outdated), aerial photographs, non-scale drawings from reportUnsignalized: Work-order requests, sketches on turning movement counts, and coders assumptions based on volume |
Signal plans, pavement marking drawings, and aerial photographs |
Intersection "change" data |
Montgomery County historical signal timing files |
San Diego historical timing files |
San Francisco historical timing cards |
Traffic signal phasing data |
Montgomery County signal timing files |
San Diego signal timing files |
San Francisco signal timing files |
LEDs and backplates |
These data are not maintained |
Requested but never received from City of San Diego maintenance staff |
Although the city uses LEDs, it was not able to provide installation dates |
RLC installation date |
Montgomery County Department of Public Works (DPW) |
City of San Diego Traffic Engineering Division |
San Francisco Department of Parking and Traffic (DPT) |
RLC signing |
Montgomery County DPW provided general information |
City of San Diego Traffic Engineering Division policy |
San Francisco signing database |
RLC ticket protocol |
Montgomery County DPW |
City of San Diego Traffic Engineering Division |
San Francisco DPT |