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Direct User Benefits or Disbenefits noise impacts are likely to be insignificant because existing bus service is being replaced by a BRT ser- Travel time changes: Travel time savings would vice. Therefore, the research team ignores noise costs arise from a project that converts an arterial lane to in this analysis. BRT due to the reduction in travel time for transit pas- sengers who originally used the existing bus service. Indirect Benefits Auto drivers would also likely see a change in travel time due to a reduction in arterial capacity and also A BRT project is likely to have other benefits that a reduction in traffic volume (due to some auto mode are not directly related to the amount of travel on the shift to transit). Travel time benefits are valued in facility, but arise as an indirect effect. These could terms of the hourly wage rate, under the assumption include the following: that time not spent in travel can be used for other activ- ities having economic value. Land development impacts involving a change Travel cost savings: Savings or increases in in the use and value of properties located near travel costs include out-of pocket vehicle operat- the new BRT corridor. ing and ownership costs and are directly related to Savings in parking costs for drivers who switch the change in the number of vehicle miles traveled modes from auto to the new BRT service and/or by auto drivers. Vehicle operating costs include the reduction in the need to provide vehicle park- costs of fuel, oil, maintenance, insurance, and depre- ing in the CBD. ciation associated with vehicle wear. Travel costs also Savings in reliability that would accrue to BRT include the fares paid by transit riders on the exist- riders. ing bus service and the new BRT service. Economic impacts from enhanced accessibil- Crash costs: If some auto drivers switch their ity to employment. travel mode to the new BRT service, costs related Savings in operating costs for the transit agency to vehicle crashes will decline. While some part of due to the higher efficiency of the BRT service. crash costs are perceived by travelers and included Quantification of indirect benefits is challeng- in their calculation of travel cost through insurance, ing for a cost/benefit analysis focused on a single the costs to other drivers and the costs to state and BRT project. In this study, the research team does municipal governments of responding to crashes are not quantify indirect benefits of the BRT project for typically not perceived by travelers when making two reasons. First, it would be difficult to isolate the travel decisions and must be calculated separately impacts of the BRT project alone since these indirect (ECONorthwest 2002). benefits are influenced by several external factors. Second, the business and employment benefits are Direct Social Benefits typically not included in project-level analyses since Environmental impacts or externalities, includ- they are assumed to be transfers from other regions ing savings in emissions damage costs and noise or from parts of the same region. costs experienced by those not using the BRT facil- ity, are considered the direct social benefits of the SECTION 4 ILLUSTRATIVE ANALYSIS project. Emission reduction: The change in emissions The most critical component of a cost/benefit cost damages are directly related to the change in the analysis for a BRT project is the estimation of impacts number of trips and vehicle miles traveled by auto on vehicle delay and transit ridership. While the drivers. To the extent that the new BRT corridor can calculation of these impacts will differ with every encourage drivers to take transit, emissions are likely project, it is possible to evaluate hypothetical proj- to decline. However, a BRT conversion could have ects using plausible ranges for key parameters so a negative impact on total vehicle emissions if con- as to illustrate how these parameters influence the gestion on the remaining mixed-flow travel lanes outcome. increases significantly. In this section we describe a cost/benefit analysis Noise Reduction: Motor vehicle noise imposes for a hypothetical BRT project to illustrate how the an economic cost on those living or working in close benefits of such a project are affected by key param- proximity to the facility. For this hypothetical project, eters such as traffic volume, change in travel time, 6

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and baseline mode shares. The results of this analysis using the HCS. The research team also estimated the are expected to help transportation agencies under- number of additional buses that would be required to stand the types of conditions under which convert- accommodate the increased ridership from the mode ing a lane to a BRT lane is likely or not likely to have shift. Using assumptions for transit and auto speeds net benefits. before and after the BRT project, the research team estimated the change in travel time in vehicle hours traveled (VHT) for drivers and transit users, com- Methodology paring No Build with a BRT Dedicated Lane Alter- Our analysis compares a No Build baseline alter- native. We multiplied that change by value of time native with a BRT alternative that involves taking a parameters to monetize the delay benefit/disbenefit. mixed flow lane from a three-lane arterial and using Based on the change in ridership and the number it for dedicated BRT. The analysis involves defining of auto drivers that shift to transit, we calculate the a number of assumptions regarding the physical char- change in vehicle miles traveled (VMT) for the No acteristics of the facility, its traffic controls, traffic Build case and the BRT case. This is used to estimate volume, and baseline travel characteristics. We con- the changes in vehicle operating costs for users. Esti- sider ranges of values for several key variables that mates of change in VMT were also used to calculate would cover the range of conditions likely to be expe- change in emissions damage costs and crash costs. rienced by transportation agencies. The research team used a discount rate of 7% to We begin with an assumption for baseline daily discount the costs and future stream of benefits, per person throughput--equivalent to the number of per- guidance from the Office of Management and Bud- sons traveling in the corridor by automobile or bus get (OMB 2003). The OMB guidance states that a service. From this assumption we calculate peak hour real discount rate of 7% should be used as a discount and peak direction vehicle volume and transit riders. rate "as a default position." The 7% rate is an esti- The total person throughput is assumed to remain mate of the average before-tax rate of return to pri- constant. Benefits and costs accrue due to changes in vate capital in the U.S. economy. The guidance also travel time and mode shift. recommends that analysts use other discount rates to We use the Highway Capacity Software to calcu- show the sensitivity of the estimates to the discount late automobile speed and delay for the No Build and rate assumption. For instance, lower discount rates BRT project, for each combination of input variables. are appropriate in cases where the project or policy To determine the likely change in transit ridership due does not primarily impact the allocation of capital, to improved transit service, we used elasticity values rather it directly affects private consumption. The from the literature to estimate the following: alternative most often used is sometimes called the Ridership increase from travel time savings: "social rate of time preference." This simply means the rate at which society discounts future consump- range assumed is -0.5 to -0.7 for work trips and tion flows to their present value and has averaged lower for general trips (Kittelson 2007, Cam- around 3% in real terms on a pre-tax basis. The OMB bridge Systematics 2009). To add in the effect therefore recommends providing estimates of net of increased reliability, -0.1 may be added benefits using both 3% and 7% discount rates; the (Cambridge Systematics 2009). The research research team applied a 3% discount rate as part of the team used -0.6 in this analysis. sensitivity analysis. Table 3 lists some of the fixed Ridership increase from reduced transit head- assumptions, variables, and calculated parameters in ways (increased frequency): range assumed is the analysis. -0.4 to -0.5 (TRB, 2005; Kittelson 2007). Finally, the research team conducted a sensitiv- The research team used -0.4 in this analysis. ity analysis by altering the values of key variables, These additional riders are assumed to shift their including mode shares, average daily traffic, BRT travel mode from auto to transit, thus keeping the total headway, and BRT speed. Altering the user costs for number of travelers in the corridor the same before autos and transit will also lead to a change in benefits; and after the BRT project. Based on the increase in however, the research team did not include this in the transit ridership, the research team calculated the sensitivity analysis. Fares on transit were assumed to change in traffic volumes on the remaining general be the same in the existing bus service and in the new purpose lanes and the corresponding change in speed BRT service. 7

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Table 3 Assumptions, variables, and calculated parameters. Calculated Parameters Fixed Assumptions Variables (both mixed flow and BRT lanes) Capital, operating, and Total auto and transit travel Average vehicle miles traveled (VMT) maintenance costs demand in a corridor (persons) Vehicle delay, LOS Urban Street Class III Mode shares Person delay Discount rate User costs for autos and transit Average auto speed Number of lanes Average BRT speed Vehicle throughput Signal timing and spacing Average BRT headway Person throughput Average vehicle occupancy (autos and transit) Transit ridership growth rate Auto ridership growth rate Transit ridership elasticity wrt travel time Transit ridership elasticity wrt bus frequency Average wage rates To assess the costs, the research team gathered The analysis also assumes that all existing transit data regarding assumptions for BRT costs as a func- riders will transfer to the new BRT service, implying tion of physical characteristics of the facility and sta- that all existing transit buses on the corridor will be tions, vehicle type, and operational characteristics replaced by BRT. For the Base Case analysis, the pre- (Kittelson 2007). All costs and benefits are reported project auto and transit mode shares in the corridor in constant 2009 dollars. are assumed to be 85% and 15%, respectively. Exam- ples of pre-project mode shares on arterial BRT cor- ridors are difficult to find, but we believe this assump- Assumptions and Sources for Data Inputs tion for mode shares in corridors where BRT is being Overall Assumptions considered is likely to be conservative. For instance, the feasibility study for the proposed BRT corridor The cost/benefit analysis described in this report on Geary Boulevard in San Francisco estimates that is for an urban BRT line created on a three-lane arte- buses serve as much as 25% of the trips made in the rial by taking one lane, leaving two general purpose Geary corridor during the PM peak hour (SFCTA, lanes in the corridor. The analysis considers traffic 2007). volumes and speeds in the peak periods and peak direction of traffic. The peak traffic period is assumed Arterial Speed and Volume Assumptions to be 6 hours in duration, including three AM and three PM hours. The percentage of traffic volume The Highway Capacity Software, which applies assumed to be in a single peak hour is 10% of the methods defined in the Highway Capacity Manual average annual daily traffic (AADT), with 60% of (Transportation Research Board 2000), was used to the peak volume assumed to be in the peak direction. estimate the relationship between hourly traffic vol- Because we are considering a BRT line into the CBD, ume and speed. As defined in the Highway Capac- it is reasonable to assume that there is minimal traffic ity Manual, the research team selected the Class III congestion and work travel in the reverse direction. arterial for the analysis. Therefore, we do not calculate benefits in the reverse The research team made assumptions for road- commute direction. The research team also assumed way characteristics, signal characteristics, and traffic that benefits would be minimal during off-peak peri- characteristics. Road characteristics include arterial ods, and did not calculate any off-peak benefits. The class, free flow speed, number of through lanes, and research team assumed benefits occur for 300 days median treatment. Signal characteristics include sig- per year, based on a range of 250365 as seen in nal density, vehicle arrival type, signal type, signal the literature. cycle length, and green-to-cycle length ratio. Traffic 8

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Table 4 Input assumptions for HCS arterial the Highway Capacity Manual, as well as professional planning analysis. experience and observation. The average travel speed during the peak hour was calculated based on the spec- Urban Street Class III Street Type Urban Principal Arterial ified volume and road characteristics. Table 4 lists Intermediate Minor the assumptions used in the HCS analysis. The analy- Arterial sis was done for an 8-mile segment of the corridor; Free Flow Speed (mph) 35 both transit riders and auto drivers are assumed to Left-Turn Bays Yes travel this length in a single trip. Median Yes Segment Length (mile) 8 Capital Costs Signals per mile 6 Arrival Type 5 TCRP Report 118 presents a range of capital Operational A highly favorable costs for BRT systems, depending on facility type, Characteristics progression on an station type, vehicle type, fare collection system, urban street, which and other information and safety systems. We used receives high priority this source to estimate capital costs for the hypo- in signal timing. thetical example. For the illustrative analysis, the Signal Type Actuated research team assumed the scenario of a lane within Cycle Length (sec) 80 the existing roadway profile, at-grade typical sta- Effective Green Ratio 0.5 tions (enhanced), standard vehicles, off-board fare Directional Distribution 0.5 collection, the availability of traffic signal priority, Factor passenger on-board information, and other standard Adjusted Saturation 1750 ITS, safety, and security systems. Table 5 shows Flow Rate (passenger the assumptions for capital costs that were used in cars per hour of green the analysis, along with the full range of costs for per lane) different BRT features. Lane construction costs are Planning Analysis 0.1 Hour Factor for unfinished pavements and exclude right-of-way Peak Hour Factor 0.9 acquisition costs, but include engineering and design % turns from Exclusive 20 costs. Capital costs are assumed to be spent over Lanes 2 years, starting in 2011. BRT Operations and Maintenance Costs characteristics include the directional distribution fac- Annual BRT operation and maintenance costs tor, adjusted saturation flow rate, planning analysis were assumed to be $10,000 per lane mile (in 2004 hour factor, peak hour factor, and percent turns from dollars), assuming minor reconfiguration or widen- exclusive lanes. ing of the arterial, based on figures provided in TCRP The input values for these characteristics were Report 118. These were converted to constant 2009 determined based on the range of values suggested in dollars for use in the analysis. Table 5 Capital cost assumptions. Capital Cost Assumptions Value ($) Notes/Units Lane within existing roadway profile 2,700,000 Cost per lane mile At-grade station with enhancements 30,000 per station New Articulated Vehicles 675,000 average per vehicle On-board fare collection 17,500 average per vehicle Traffic Signal Priority 30,000 per intersection Passenger on-board information 4,000 per vehicle Other (ITS, safety, security systems) 90,000 70,000120,000 per vehicle, depending on features Source: TCRP Report 118: BRT Practitioner's Guide, 2007 Notes: All component costs reported above are in 2004 dollars and were converted to constant 2009 dollars for use in the analysis. 9

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BRT Operational Characteristics analysis, it is more realistic to assume a zero value for the change in travel time costs rather than a neg- The results of the cost/benefit analysis are highly ative value. dependent on how the project changes travel time and wait time for transit riders. Numerous existing Auto Operating Costs BRT systems have demonstrated substantial reduc- tions in travel time and headways compared to con- These costs include ownership costs and were ventional bus service. For the purposes of the base assumed to be 54 cents per mile using figures from case example, the research team relied on the average the American Automobile Association (AAA 2009) bus speeds presented in the FTA's Characteristics that include costs of fuel, maintenance, tires, insur- of Bus Rapid Transit for Decision-Making (2009). ance, license, registration and taxes, depreciation, and We assume an average stop spacing of 0.2 miles and financing and are based on an assumed 15,000 miles average dwell time of 30 seconds. In this situation, driven per year. bus speeds on general purpose traffic lanes (No Build alternative) are estimated to be 7 mph. Bus speeds Transit Fare on dedicated arterial street bus lanes (BRT alterna- tive) are estimated to be 11 mph. This reflects a 36% The research team assumed the average adult sin- improvement in transit travel time. gle trip bus fare to be $1.30, based on statistics avail- The research team assumed an average bus head- able from the American Public Transport Association way of 10 minutes under the No Build alternative. (APTA 2007). Using 60-foot articulated buses with a maximum capacity of 80 passengers, this headway implies a Vehicle Occupancies maximum transit throughput of 480 riders per hour Average auto occupancy during peak hours was in the peak direction. For the BRT alternative, the assumed to be 1.2 and transit occupancy was assumed research team assumed an average bus headway of to be 80 passengers for both standard existing articu- 6 minutes, or a maximum transit throughput of 800 lated buses and BRT buses. riders per hour in the peak direction. This capacity is sufficient to accommodate the transit demand under Emissions Rates and Emissions Damage Costs all the BRT scenarios analyzed in this report. Emissions rates for light duty vehicles were avail- Value of Travel Time able from the EPA (2005) and damage costs were EPA figures assumed in the National Highway Traf- The research team assumed value of time esti- fic Safety Administration's (NHTSA) Corporate mates of 50% of wage rate for in-vehicle time and Average Fuel Economy for MY 2012-MY 2016, 100% of wage rate for access, waiting, and trans- Passenger Cars and Light Trucks (NHTSA 2009), fer time (ECONorthwest 2002). The average wage reported in 2007 dollars (see Table 6). These costs rate in constant 2009 dollars was assumed to be were converted to constant 2009 dollars for calcu- $26.29 per hour for transit riders and auto drivers lating the cost/benefit ratio. The change in emissions (U.S. DOT 2003). for buses has not been taken into account. While the Note that auto drivers who shift to BRT are likely emissions per bus-mile will remain constant, bus to incur an increase in travel time, and thus an increase emissions are likely to be higher in the BRT case in travel costs. Therefore, these travelers would expe- rience a net travel time disbenefit. Consistent with other literature, the travel time disbenefit to auto Table 6 Emission rates and emission damage drivers is not assigned a negative cost, but rather costs assumed. is assumed to be zero. This is because, while auto Emission Rates Emissions Damage drivers diverting to BRT experience this travel time (grams/mile) Costs ($/ton) disbenefit, it is clear there must be benefits other than travel time that cause drivers to switch to BRT. VOCs 1.36 1,300 These can include benefits such as the convenience NOx 0.95 5,300 of not driving, increased productivity due to the use SOx 0.008 31,000 Particulates 0.01 290,000 of travel time for doing other work, less stress, and CO2 369 20 so on. Since these benefits cannot be captured in this 10

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because bus VMT will be higher. However, this year over the life of the project in constant 2009 dol- increase in bus emissions due to increase frequency lars. Costs of infrastructure and station construction, has a negligible effect on the net benefits of the on-board fare collection, vehicles, traffic signal pri- project. ority, as well as other on-board information, safety, and security systems constitute the total capital costs. Crash Costs The research team estimated these costs based on Crash costs per vehicle mile traveled for light the assumption of a bus lane on an urban arterial duty vehicles was available from the EPA and was constructed within the roadway profile. The largest assumed to be $0.023, as referenced by NHTSA proportion of costs (60%) is for construction of a (NHTSA 2009) and reported in 2007 dollars. These BRT lane within the existing right-of-way, followed costs were converted to constant 2009 dollars for by purchase of new articulated buses (28%). Our calculating the cost/benefit ratio. analysis for the hypothetical case shows that fifteen new buses would be required to accommodate the increased ridership. The increase in ridership is within Results the bounds of the maximum peak hour peak direction The research team calculated costs and benefits BRT capacity in the assumed corridor. for all categories over a period of 22 years, assum- Table 8 shows the different categories of bene- ing initial construction costs over a period of 2 years fits (and disbenefits) that accrue to users and non- and discounting future benefits and Operation and users of the arterial under in the base case scenario Maintenance (O&M) costs over a period of 20 years (40,000 daily person throughput). A project of this after construction. nature that involves reducing capacity for autos while Table 7 shows the total capital costs under vari- creating a BRT lane is unique from other stand-alone ous cost categories and the O&M costs incurred every transit projects in that it results in a substantial dis- benefit to auto users, while bringing substantial ben- efits to transit riders. This reduces the net user benefit Table 7 Costs of converting an arterial lane to a in terms of travel time and out-of pocket cost savings BRT lane for hypothetical corridor*. that can be expected from the project. Based on the research team's assumptions, the analysis shows that Capital Costs Constant 2009 $ the benefits to transit riders exceed the disbenefits to Construction of lane within $24,531,494 auto drivers by a factor of approximately 3.5. Smaller existing roadway profile for savings occur due to the reduction in crash costs and 8-mile corridor1 emissions, which depend on the reduction in VMT by At-grade stations2 $1,362,861 auto drivers diverting to BRT. The sensitivity analy- Articulated buses3 $11,499,138 sis in the next section shows how these benefits vary On-board fare collection system3 $298,126 under alternate assumptions. Traffic Signal Priority4 $1,635,433 Passenger on-board information3 $68,143 Other (ITS, safety, security $1,533,218 systems)3 Table 8 Annual peak period benefits of converting an Capital costs assumed over $40,928,413 arterial lane to BRT (40,000 daily person throughput). two years Annual O&M Costs5 $90,857 Annual Peak Period Benefits Constant 2009 $ *Costs above based on unit costs in Table 5, converted to constant Benefits for transit riders $4,107,426 2009 dollars. continuing to use transit 1: Costs are for unfinished pavement, exclude right of way costs, Disbenefits for auto drivers -$1,189,190 and include engineering and design costs. continuing to drive 2: Total costs for 40 stations, assuming 5 stations per mile on 8-mile Savings in crash costs $425,733 corridor. Savings in emissions $321,014 3: Total costs for 15 vehicles. damage costs 4: Total costs for traffic signal priority on 48 intersections, Total Annual Peak Period $3,664,982 assuming 6 intersections per mile on 8-mile corridor. (AM and PM) Benefits 5: Includes costs of street lighting and routine maintenance. 11