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42 Figure 5. Facility costs spreadsheet. Demand use, facility planning, and community design, bicycling and walking differ substantially. The cost, demand, and The next process estimates the induced demand as a result benefit tool for this project were developed specifically of the facility. In doing so, the guidelines consider the exist- with bicycle facilities in mind. Many elements of the tool, ing bicycle commute share, residential density at 400, 800, however, can be applied to pedestrian facilities. For exam- and 1,600 m from the facility, household size, and length of ple, cost information can readily be adapted for pedestrians facility. The guidelines have default settings for each metro- to the existing cost model, given the constraints described politan area. However, the user has the ability to change in this section. On the other hand, demand and benefit cal- these figures if better information about the area around the culations would need to be considerably modified to meet facility is available (Figure 6). the unique characteristics of pedestrians. This section describes the manner in which the designed tool could be applied to matters of pedestrian planning and some of the Output issues involved. The guidelines present the user with easy to read tables showing the costs of a new facility and the induced demand Important Issues to Consider and benefits related to mobility, recreation, health, and reduced auto use (Figure 7). It is helpful to draw attention to two points when consider- ing specific facilities. The first is that there are facilities devel- APPLICATION TO PEDESTRIAN FACILITIES oped specifically for pedestrian use and most of the time only pedestrian use (e.g., sidewalks, stairs, and street crossing Introduction improvements). Other facilities suitable for bicycle use, how- ever, tend to be used by pedestrians as well. The second point Some of the difficulty in planning for bicycling and walk- is that pedestrians, in a strict definition, are meant to include ing is that the bulk of the literature and subsequent planning people walking, versus variants such as running and skating. tools typically aggregate these two modes. For abstract or There is an important difference in terms of speed and typical general purposes this may suffice; the two modes are almost distances covered that impact how demand and benefits will always aggregated in transportation research. In terms of daily be impacted by facilities.

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43 Figure 6. Demand inputs. Figure 7. Output of guidelines.

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44 The first distinction between facility types primarily affects costs. Bicycle facilities may exclude pedestrians or be shared cost estimates. Facilities that are intended for mixed use with pedestrians and other non-motorized users. Table 8 including bicycles can obviously be addressed using the cost identifies, based on location, shared facilities for cyclists and tool in the guidelines. However, it may not be possible to esti- pedestrians as well as exclusive facilities. mate costs for facilities that are for pedestrian use only, unless Having identified the correspondence between the bicycle the physical characteristics of the facility have a close parallel and pedestrian facility type, the next step is to identify the to the bicycle facilities included in the model. construction elements required for exclusive pedestrian facil- Demand and benefit estimates tend to be more influenced by ities. Updating the cost model to include construction ele- the second point. Specific facilities and environments that may ments for sidewalks and trails would require minimal effort be very useful to walkers may not be as suitable for higher as most construction elements are already included in the speed alternatives like running and skating. Conversely, the cost model. value of a continuous off-road facility may be greater for Table 9 identifies construction elements that are exclu- higher-speed users, which in turn will influence how far they sive to bicycles and pedestrians as well as those that are will go out of their way to use these facilities, which will shared. Note that most elements are shared and included in impact demand. the existing model. A final matter is that walking is 10 times as common as bicy- To use the tool to estimate the cost of the bicycle facility, cling. An estimated 70% of adults walk at least once per week the user inputs information (such as path width) for the (in the NHTS baseline sample) while about 7% bike. Because applicable elements of the pedestrian facility type, thereby generating the appropriate cost estimate. so many people walk already it seems unlikely that new facil- ities will have a significant impact on total demand, although they may influence where walking is done. The major impact Demand on benefits will likely be the value of improved safety or gen- eral conditions for the already large number of existing pedes- Demand in terms of new bicycle users is generated based trians, rather than the value of additional activity by new users, on an extrapolation from existing mode share of bicycle com- as was the case with many of the bicycling benefits. muters to find the number of new users attributed to a given facility. This is based on two different calculations: first, esti- mating the total number of bicyclists in an area based on the Costs commute share and second, estimating the number of new cyclists as a function of the current number. Both of these Costs and benefits obtained from a self-contained project such as a multipurpose trail, striping of an existing roadway for calculations are based on the results of the research done for bicycles, or construction of a sidewalk next to an existing road- this project. way, are relatively easy to estimate by applying the guidelines. Development of an equivalent demand estimation method- However, bicycle facility costs as an element of much larger ology for pedestrians should be considered carefully. There road construction costs are more difficult to reliably estimate. is no reason to believe a priori that observed relationships In like manner, the guidelines can be more readily applied between recreational and commuter bicycling would hold to self-contained pedestrian paths than sidewalks built as part for walking or other potential facility uses. Nor is there any of roadway projects, particularly in urban environments. reason to think that there would be a similar relationship Urban roadway projects will often include essential elements between marginal improvements to facilities and the amount to create a quality pedestrian facility which include not only of walking. Indeed, there are good reasons to believe that the sidewalk material but also street trees, landscaping, these relationships would not hold. benches, trash bins, and public art--all of which are often important to creating inviting pedestrian environments. 1. Adequate facilities for walking are much more wide- The cost model was designed to estimate bicycle facility spread (e.g., sidewalks). There may not be good facili- construction and design cost for all types of on-street and ties on specific roads, but most people have some place off-street facilities, equipment such as racks, and real estate that is reasonable for walking. In general, because of the TABLE 8 Conveyance Location Bicycle Shared Pedestrian Street Bike Lane Paved Shoulder Shared Street Shared Lane - - Adjacent Street Side Path - Sidewalk Cycle Track - - Off-Street Multipurpose Path Walking Trail Stairs

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45 TABLE 9 Construction elements Bicycle Shared Pedestrian Pavement Markings Earthwork Benches Bicycle Parking Pavement Bus Racks Drainage Landscaping Bridges Underpasses Signs Traffic Signals Barriers Lighting Security Real Estate Operations Costs Maintenance Costs wealth of existing pedestrian facilities, new pedestrian The conclusion that follows from these points is that not facilities are less likely to create major changes to the only is the bicycling demand model in the guidelines not overall opportunity set as they often do for cycling. They applicable to pedestrians; in fact, it cannot even be adapted seem unlikely to have a major impact on the total amount because of the significant differences in the underlying of walking, although they may impact where it is done circumstances for the two user types. and the benefits that it provides (e.g., providing a side- In two respects, estimating pedestrian demand is simpler walk connecting two formerly auto-oriented centers). and more reliable than estimating bicycling demand. First, 2. In more developed areas, pedestrians are generally sep- because walking is so much more common, there will not be arated from traffic; therefore, off-road facilities do not such large variations across different cities or between differ- create the same kind of unique advantages that they ent parts of the same city. Because it is more common, it would do for bicycles, at least in the case of walking (this be much easier to complete representative counts in a given would be different in rural areas). However, for run- area to estimate local demand. Furthermore, local variations ners and skaters, their higher speeds and longer dis- are smaller; it is therefore appropriate to estimate demand on tances could mean that facilities without frequent a new or improved facility based on known demand on a intersections could be advantageous. similar facility at a different location. 3. The relevant travelshed for walking is smaller than for The second reason estimating pedestrian demand is more cycling. Most walking trips are quite short; unless a straightforward stems from the fact that walking facilities facility is extremely close to a person's home or work, are also more common. For any facility with given charac- they are unlikely to use it much. There could still be teristics--a sidewalk in a suburban commercial area--it is drive-in traffic for recreational walking, but only if the likely that one or more very similar facilities exist in the same facility is special in some way (e.g., scenic). urban area, and if not, then almost certainly in some other 4. Cycling also tends to be more influenced by attitudes similar city. Thus estimating demand by comparing existing and facilities; rates of commuting are an indicator of facilities is more feasible for walking facilities than it is for these attitudes and facilities that can also be used bicycling facilities, and probably more accurate as well. This to predict recreational cycling. Commuting and recre- is likely true of mixed use as well as pedestrian-only facilities, ational cycling to some extent benefit from the same although some basic research to confirm these hypotheses kinds of conditions. Walking does not seem subject to would be valuable. the same cultural and facility limitations. Furthermore, commuting by walking is strongly constrained by local land use density due to the short distances involved, Benefits whereas walking for recreation is not. So there is no rea- son to believe that there would be a strong relationship Three bicycling benefits included in the guidelines rely between commuting and total walking at a neighbor- in part on demand estimates. The number of new bicyclists hood or even an urban area level, as there appears to is multiplied by a per-person dollar amount to calculate be for cycling. health, recreation, and mobility benefits. Of these, health and

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46 recreation could directly apply to pedestrian facilities with- ence survey to assign value to five types of bicycle facilities. out further study, assuming an established methodology for A similar survey could be used for pedestrian facilities, but estimating induced pedestrian demand. It could be assumed would require a new framework for considering different that pedestrian facilities would generate $128 per year in types of facilities. health benefits to new pedestrians who did not formerly The externalities benefit assumes that new bicycle com- engage in physical activity. The same assumption would muters induced by a new facility will generate benefits in the hold true for recreation; new pedestrians would value their form of less congestion and air pollution. The former relies on recreational time at the same rate as their cycling counter- the fact that bicycle facilities typically separate cyclists from parts. autos. Applying this logic to pedestrian facilities presents the The mobility benefit also relies on an estimate of demand, problem that increased pedestrian traffic, even on sidewalks, but cannot be applied directly to pedestrian facilities. The can actually increase automobile traffic congestion at inter- methodology employed to assign value to bicycle facilities sections. For this reason, the methodology employed to cal- did not consider pedestrian facilities. To determine the mobil- culate the externalities benefit would need to be substantially ity benefit, the research team used an adaptive stated prefer- modified to apply it to pedestrian facilities.