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62 because of high traffic volumes. Conditions that support the TABLE 18 construction of curb extensions related to bus operations RANGE OF CAPITAL COSTS FOR ADDING NEW TRANSIT LANES ON URBAN STREETS include: Type of New Arterial Cost Range (exclusive of right-of- Street traffic speeds are relatively low. Transit Lanes way and with uncolored pavement) General traffic volumes are relatively low (fewer than Curb or off-set lanes (bus) $2 to $3 million per lane-mile 400 to 500 vehicles per hour). Median transitway (bus) $5 to $10 million per lane-mile Right turns are relatively low (particularly for larger Median transitway (LRT) $20 to $30 million per track-mile vehicles such as trucks). Source: TCRP Report 90 (4). Bus stop patronage and overall pedestrian volumes are substantial. On-street parking is available. Two travel lanes are available in the particular direction costs are substantially higher. In Boston, the reconstruction (to allow passing of stopped buses). of 2.2 miles of Washington Street for the Silver Line Phase 1 There is interest on the part of local business/property cost $10.5 million per mile, of which about 20% was for owners for such treatments. brick-paved sidewalks and crosswalks, architectural street lighting, and landscaping. Curb extensions can only be applied where it is possible to widen the sidewalk either at an intersection or mid-block. For The O&M cost for dedicated bus lanes includes the costs use as bus stops, curb extensions are typically associated with for street lighting and routine maintenance (e.g., pothole filling near-side bus stops. If far-side stops are developed as curb and resurfacing, cleaning, and snow plowing). The incremen- extensions, blockage to general traffic caused by the bus stop- tal O&M costs for a dedicated bus lane depend on the nature ping should not result in unacceptable queuing and potential of the situation before and after the dedication. If the dedicated traffic conflicts at the intersection. Thus, with far-side curb bus lanes were formerly devoted to either parking or general extensions, two travel lanes are desirable. traffic, there would be no incremental operating and mainte- nance costs other than those associated with more frequent Other conditions that may limit the use of curb extensions maintenance given the greater wear and tear associated with include two-lane streets, complex drainage patterns, and high bus operation. bicycle traffic on the street. The O&M costs of the new dedicated bus lanes themselves are not the only O&M cost impact. If a bus lane saves enough CAPITAL AND OPERATING COSTS time such that a decrease in the number of buses necessary to provide a given level of service is possible, there will be a Median Transitways and Bus Lanes decrease in transit operating and maintenance costs as well. The cost of implementing dedicated bus lanes depends on the existing roadway configuration and the extent of the planned If the proposed dedicated lanes result from a widening, the changes to accommodate dedicated lanes. Unit costs for both incremental O&M costs would be modest; certainly under initial construction and subsequent lane operation and mainte- $10,000 per lane-mile per year (based on national average O&M costs for arterial streets). nance can be obtained from local government and state DOTs in the respective community. Most transit agencies have fully allocated or marginal O&M cost models that have vehicle hours and peak vehicle Capital costs are affected by ROW needs and costs, the requirements as primary input. Analysis of revenue service design details of the existing street (e.g., Are utilities to be travel speeds and times is necessary to determine the degree to moved? Is a median to be cleared and paved? Will sidewalks which both of these would be decreased as the result of the be rebuilt?), and the design details of the new lanes them- dedicated bus lanes. selves. If existing lanes are used with no new construction, the initial capital costs will primarily be limited to modest re-striping and signage costs. Transit Signal Priority According to TCRP Report 90, published in 2007, the Costs for implementing TSP along a transit corridor will range of costs for adding new bus lanes is as identified in depend on the configuration of the existing signal control Table 18 (4). system, with higher costs associated with signal upgrades, equipment/software for the intersection, vehicles, or the Where existing lanes are converted to bus lanes, capital central traffic control and transit management systems. costs may range from $50,000 to $100,000 per mile for re-striping and signing. Where street reconstruction is Costs specifically associated with TSP are highly dependent required to provide new bus lanes, as noted in Table 15, the on whether the TSP system will be localized to a corridor or

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63 centralized and integrated into a transit or regional traffic Queue Jumps and Bypass Lanes management center. To implement a conditional priority system, the central signal system may be integrated into the The cost of a queue jump or bypass lane will vary widely based transit management center. A key assessment in determining on whether or not there is an existing right-turn lane or shoul- cost is whether or not existing traffic control software and der present to develop a transit queue bypass. If existing road- controllers are compatible with TSP. Estimates for traffic way lanes or shoulders are available to develop an adequate signal controller replacement range between $3,500 and queue jump or bypass lane treatment, then the costs of the $5,000, depending on the vendor and the functionality pre- installation will focus on roadway signing and striping modi- scribed for TSP. Costs for communication links needed to fications and the provision of a separate signal for the queue integrate these traffic signals into the existing signal system jump treatment. For applications in the United States, the sign- and costs for future signal system upgrades would be extra ing and striping costs have ranged from $500 to $2,000. The and would vary depending on the specific signal system con- cost of a bus queue jump signal is estimated to range from figuration and extent of TSP application. In general, if exist- $5,000 to $15,000, based on the type of detection deployed. A ing software and controller equipment can be used, costs queue jump signal with loop detection typically has a lower can be under $5,000 per intersection; however, costs can cost than with video detection. increase to $20,000 to $30,000 per intersection if equipment needs to be replaced. The development of a new separate lane for buses for a bypass or the development of a new or lengthened right- or Costs for transit detection vary significantly based on the left-turn lane will be dependent on the availability of ROW, ultimate technology chosen. Table 19 provides ranges and existing utilities present, and other roadside features. Costs for typical capital and operating costs for different TSP detection new lane construction will vary widely based on the extent systems. of roadway reconstruction, utility modification, and ROW TABLE 19 COSTS OF DIFFERENT TSP DETECTION SYSTEMS Equipment Operating and Jurisdictions Cost/ Equipment Maintenance Using This System Technology Intersection Cost/Bus Costs Detection Optical Optical emitters Moderate Moderate Emitter Portland; San ($8,000 ($1,000) replacement Francisco; $10,000) ($1,000) Tacoma; Kennewick, WA; Houston; Sacramento; ,and others Wayside Radio frequency High Low ($50) Tag replacement King County, Reader technology. Uses ($20,000 ($50) WA vehicle-mounted tags $40,000) and wayside antenna, which must be located within 35 ft of transit vehicle. Radio transmits and decoder reads rebound message. Smart " Loops Loop amplifier detects Low ($2,500 Low Same as loop Los Angeles; transmitter powered per amplifier; ($200) detector Chicago; by vehicle's electrical use existing Pittsburgh; San system. loop detector) Mateo County, CA GPS GPS receivers Moderate High N/A Broward County, mounted on transit ($6,000 ($2,500) FL; San Jose vehicle. Line of sight $10,000) not required for detection. Wireless Applies unused Moderate Moderate High if Cellular Los Angeles bandwidth. Use of (Under (under Digital Packet County mesh networking. $10,000)-- $1,000) Data system, low Dependent on if LAN number of access points N/A = not available; LAN = local area network. Source: TCRP Report 118 (2007) (5) and JTA ITS Signal Priority Program Study Final Report (2008) (31).