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The BCI model can also be used to assess long-range transportation plans and the alternatives that may be proposed. The following example illustrates how the model can be used to plan for a bicycle corridor. A suburban area on the west side of the city is currently growing at an exponential rate and is expected to triple its population base within the next 10 years. Consequently, there is a need to either upgrade the major arterial that currently provides access between this area and the central business district or build a new roadway to accommodate the expected increase in traffic. The present arterial is a four-lane facility with a variety of retail and commercial development along the roadside with virtually no right-of-way for additional lanes.
Based on a cost-feasibility study, the decision was made to build a new roadway with a 1.2-m bicycle lane to accommodate bicyclists. Since there is no provision for bicyclists on the current arterial, this plan initially sounded like a major victory for bicycling commuters. The proposed roadway is a six-lane arterial with a projected traffic volume of 50,000 vpd and a posted speed limit of 75 km/h. The travel lanes will be 3.6 m wide, trucks are expected to comprise 5 percent of the volume, and 10 percent of the traffic is expected to turn right into driveways or onto minor streets. All of these data were entered in the data entry worksheet as shown in figure 11 for Planning Example - Proposed New Arterial. The results, shown in figure 13, indicate that the BCI for this new proposed arterial will be 5.47. This value translates into a LOS F and indicates that the facility will be extremely incompatible for bicycling. So while the addition of a bicycle lane looked like a good idea, the reality is that the combination of other geometric and operational characteristics would create an unfriendly environment for bicyclists.
Since increasing the bicycle level of service to LOS C or better on the new proposed arterial could simply not be done within the right-of-way constraints, it was necessary to look for alternatives to provide a bicycle route within this same corridor. One alternative proposed by the local resident engineer consisted of removing the bicycle lane from the new facility and using the cost savings resulting from the reduced right-of-way needs to improve the old (existing) arterial to accommodate bicyclists. Once the new arterial is built, traffic on the existing roadway is expected to decrease to 15,000 vpd. The percentage of trucks is also expected to decrease to 2 percent while the percentage of traffic making right turns is expected to increase to 20 percent since a greater number of users of this roadway will now be individuals interested in patronizing one of the local businesses. The estimated 85th percentile speed is expected to remain at 75 km/h. The current configuration of lanes on this roadway is four 3.4-m through lanes (two in each direction) and a substandard 3.8-m two-way-left-turn lane (TWLTL). The proposed new configuration eliminates the TWLTL, increases the through lanes to 3.6 m in width, and includes 1.5-m bicycle lane on both sides of the roadway. This information was entered in the data entry worksheet in figure 11 for Planning Example - Re-designed Existing Arterial. The results, shown in figure 13, indicate that the BCI for this new proposed arterial will be 3.04. This value translates into a LOS C and indicates that the bicycling compatibility level will be moderately high. Ultimately, these results indicate the need to revise the plans for the new arterial, including reducing the right-of-way required, and the need to plan on reconfiguring the existing roadway to create a more user-friendly roadway for bicyclists.
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