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6 destinations for travel by all modes and are generally served Table 2-1. Rating system for sidewalk coverage. by the highest-frequency, highest-capacity transit services in Rating Criteria for planners Criteria for laypersons a region. Most streets do not have A person cannot walk there; he/she 1 Ridges are generally the best locations for traditional line- sidewalks. must use the street. Many streets do not have haul transit services, including rail and fixed-route bus 2 sidewalks--there are many It is difficult to walk there--there are lots of gaps in the sidewalk. services, since they have a relatively high number of trip gaps in sidewalks. ends within walking distance and since the mix of uses There are sidewalks on at A person could walk there but it 3 least one side of most streets. would not be very easy or pleasant. provides a source of relatively high, all-day travel demand. It is fairly easy to walk there but There are sidewalks on nearly Points are among the most difficult locations to effectively 4 every street, but not always on there are some places where it could be improved (e.g., serve with fixed-route transit. Not only are points geo- both sides. crosswalks, lighting needed). graphically dispersed, but their travel demand also tends to There are sidewalks on both It is very easy to walk there be concentrated at certain times of day. As a result, these 5 (extensive sidewalks, crosswalks, sides of nearly every street. pedestrian crossing lights). places tend to be poorly served by transit. Frequently, they receive little or no service at non-peak times, are served by dedicated trips or scheduled route deviations that can con- Design fuse customers, or require customers to walk a long dis- tance to a mainline bus route. Design was measured in terms of sidewalk and street con- Plains are also notoriously difficult to serve with fixed- nectivity and whether the area would qualify as an "urban place." route transit because of the low density, the coarsely grained Sidewalk connectivity was chosen as an indicator of the ability mix of land uses, and the lack of well-connected pedestrian for pedestrians to walk to transit stops. This was evaluated on a facilities frequently found in suburban residential areas. scale of 1 to 5, with 5 indicating the highest level of sidewalk coverage. As shown in Table 2-1, the numerical measures are correlated with descriptions from the perspective of a pedes- trian or a planner, depending on the training level of the rater. Land-Use Assessment In assessing the land-use conditions within the transit ser- Table 2-2. Rating system for street connectivity. vice areas, the research team considered the "four D's": density, Rating Description Aerial View diversity, design, and deterrents to driving. These measures 1 Very low level of street coverage; mostly a few were chosen in order to evaluate the level of transit support- collectors or arterials with a iveness of each service area. few cul-de-sacs. Density 2 Cul-de-sacs and curvilinear roads predominate; there are The density indicator was measured by calculating the few areas with grid coverage. number of people, households, and employed people in the study area. Data were most often available at the traffic analysis zone (TAZ) level provided by the metropolitan 3 Significant grid coverage but planning organization (MPO) in that region. In some cases, also a number of areas with particularly for numbers of people and households, data cul-de-sacs and dead ends. were provided in different units of geography, such as cen- sus tracts. 4 Extensive grid network with a few cul-de-sacs and dead ends. Diversity To assess the diversity of activities occurring in each ser- vice area, the research team evaluated the mix of industries and land uses present. Industry data on employment in each 5 Complete grid network with no cul-de-sacs or dead ends. service area, when available from MPOs or other sources, were summarized and presented as well. Land-use data in GIS format were also obtained from MPOs, at times at the parcel level.