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160 Evaluation and Performance Measurement of Congestion Pricing Projects 11. Singapore Electronic Road Pricing Singapore's Land Transport Authority (LTA) is a statutory board under the Ministry of Trans- port with responsibility over the country's roads and public transportation systems, including heavy and light rail, buses, and taxis. LTA was formed in 1995, consolidating four prior public- sector entities: the Registry of Vehicles, the Mass Rapid Transit Corporation, the Roads & Trans- portation Division of the Public Works Department, and the Land Transport Division of the then Ministry of Communications. Singapore is a city state of approximately 4.7 million people living in an area of 269 square miles-- roughly 3.5 times the size of Washington DC--making it the second most densely populated country in the world. Historically, roadway traffic congestion has been a significant issue for the country, especially on routes to and within the CBD located along the middle of its southern coast. LTA's stated objectives are to Deliver a land transport network that is integrated, efficient, cost-effective, and sustainable to meet the nation's needs Plan, develop, and manage Singapore's land transport system to support a quality environ- ment while making optimal use of transport measures and safeguarding the well-being of the traveling public Develop and implement policies to encourage commuters to choose the most appropriate transportation mode This last objective characterizes LTA's management of the road network, as it seeks to opti- mize use of its relatively finite road capacity while establishing policies that strongly encourage consideration of public transportation. LTA has set a target of making 70 percent of all morning peak-hour trips on public transport by 2020. Examples of policies that aggressively manage auto- mobile use and allow for at least equal consideration of alternative modes include a vehicle quota system, significant ownership and registration fees, and a hybrid congestion pricing scheme-- the Electronic Road Pricing (ERP) system. 11.1. Overview of Singapore's Congestion Pricing Singapore's Electronic Road Pricing system is a combination of area and cordon pricing that controls access into Singapore's CBD and along major access routes. The genesis of the ERP sys- tem dates to 1975 with the introduction of a manual area (radial cordon) pricing scheme for the CBD called the Area Licensing System (ALS). To enter the CBD's established Restricted Zone (RZ), an area license (coupon) had to be purchased and displayed, which was manually verified at check points. The original RZ for the ALS was determined through manual observation. In the mid-1990s, cordons along three major expressways leading into the RZ--the Road Pricing System (RPS)--were progressively introduced to complement the ALS. In September 1998, the manual ALS and RPS were replaced by the current Electronic Road Pricing system, retaining each system's cordons. The ERP system uses overhead gantries and antennae to communicate with devices installed in users' vehicles (In-vehicle Units) that use reusable credit card-like stored-value smartcards to deduct an appropriate ERP charge. The ERP charge is generally levied for entry into the RZ weekdays between 7:30 AM and 8:00 PM. Also, inside a major shopping district in the RZ, the charge is levied on weekdays and Saturdays from noon to 8:00 PM. Along major expressways and arterials approaching the RZ, the charge is gen- erally levied weekdays from 7:30 to 9:30 AM. Overall, the charge varies by vehicle type (passen- ger car/taxi, motorcycle, and heavy and very heavy goods vehicles), by gantry, and per 1/2-hour on a fixed schedule with adjustments possible every 3 months to maintain smooth traffic flow.

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Congestion Pricing Case Studies 161 The "85th percentile" criterion is applied in making this adjustment, whereby 85 percent of road- way users perceive improved conditions (LOS/speed) following the adjustment. The authority explained publicly prior to the introduction of the ERP system that they would attempt to maintain revenue neutrality with the ERP charge. As evidence, annual revenues have remained relatively flat since the introduction of the ERP system in 1998. Revenue from the ERP system, itself, is not directly reinvested into the transportation system. It is remitted to the Ministry of Finance and placed in the country's general coffer for subsequent disbursement among all government services according to need. It is noted that the public is accustomed to the pricing scheme and does not require direct evidence of reinvestment into transportation for continued acceptance. 11.2. What Is Monitored? The ERP program is administered by the Land Transport Authority. Performance monitor- ing documentation from the authority is not publicly available, but the performance monitor- ing criteria are communicated publicly. The full spectrum of LTA's performance evaluation is summarized in the accompanying Facility Performance Monitoring Summary Matrix. The matrix is a comprehensive record of all current, known metrics used to monitor performance on the facility, organized by evaluation category. Provided in the matrix for each metric used are frequency of collection, purpose, a simple indication of importance, and particular characteriza- tions of the metric that relate back to agency/facility goals or applications. An expanded version of the matrix providing sources of information and other notes is included in the Final Report for NCHRP 08-75 which is available on line. The matrix is intended to be a visual overview of LTA's complete monitoring effort, easily comparable to other cordon- or area-priced facilities with sim- ilar matrix summaries. A more qualitative discussion of how these metrics are applied in practice and which ones are the most significant is provided below. Not all metrics noted in the matrix are discussed here. The underlying performance characteristics of the ERP system that are measured and tracked carefully by LTA include an array of standard traffic theory and traffic engineering metrics/techniques specifically focused on the speed of traffic. For example, speed-flow analy- ses are performed for all travel routes (expressways, major arterials, and minor arterials) to examine congestion levels relative to target LOS. Performance measurement data is taken from five sources. An integrated data processing platform handles each of the inputs and allows for data collation and storage for analysis. 1. A fleet of roughly 7,000 taxis, equipped with GPS, and acting as floating cars--proxies--for the speeds of all roadway users 2. ERP gantries capable of measuring point speeds 3. Expressway traffic cameras (currently under expansion to arterials) located on average 500 meters apart that collectively can compute mean-space speeds 4. Loop detectors 5. Onsite origin-destination surveys Aside from traffic theory applications and critical speed-flow and mean-space speed calcula- tions, other higher level metrics are monitored and tracked for use by senior management within LTA and the Ministry of Transport. These include time to travel from benchmark locations throughout Singapore (this applies to public transport as well as roadways), system availability, and the quantification of delay into economic loss. Environmental effects and safety are not directly monitored, as these aspects are thought to correlate positively with the successful application of the ERP program and congestion reduction. Finally, when communicating system performance and

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162 Evaluation and Performance Measurement of Congestion Pricing Projects Congestion Pricing Case Studies 163 Table 11-1. Singapore Electronic Road Pricing summary matrix.

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164 Evaluation and Performance Measurement of Congestion Pricing Projects policy decisions with the public, traffic speed is used as a simple, easy-to-comprehend metric with which to characterize system operation, rather than presenting the full detail of traffic theory computations. 11.3. Other Essential Data Gathering Activities Customer input is solicited from periodic survey work and taken into account during ERP's pricing policy review. LTA staff report that public acceptance is moderate--the benefits of hav- ing the system in place generally outweigh the negative reaction to paying the charge. It was noted that the most challenging public policy issue with pricing is public acceptability, i.e., to pay for something that was previously "free," which continues to occur with the periodic expansion of cor- dons. Hence, numerous public communications programs are necessary to keep the motoring public informed. 11.4. Why Performance Evaluation Takes Place and How Performance Monitoring Data Is Used The primary function of performance evaluation is to maintain uncongested conditions within the RZ and the routes feeding into it by continually monitoring collected traffic data. For- merly, an optimal range of speeds was assigned to specific road types, and, if monitored perfor- mance below this set speed envelope was observed, a pricing policy correction could be initiated. However, it was found that not all roadway users perceived these speed ranges as correlative with satisfactory service for the price paid. Consequently in 2008, the criterion was changed to the "85th percentile" measurement as described previously. Currently, ERP's pricing policy is reviewed on a 3-month cycle taking into account the wealth of collected data and computed traffic engineering metrics based on speeds. This review dura- tion is considered optimal to allow time for traffic patterns to readjust--passing through a tran- sient period and accounting for altered driver behavior. A formal process is followed to make an adjustment to the ERP charge schedule. Approvals are required from the Minister of Transport, and the new rates are formalized through appropriate legal documents or law. In addition to adjustments to the ERP rate schedule, outward expansion of the area cordons defining the RZ and the cordons along major expressways and arterials may be deemed neces- sary, requiring additional gantries. Travel demand modeling identifies future potential cordon locations, which are monitored closely for expansion consideration. The process for cordon expansion is more involved than ERP rate adjustments and can necessitate a parliamentary-level decision. Early communication to the public is used to make it aware of potential future gantry installations, but implementation occurs only when deemed absolutely necessary. Overall, the number of gantries has roughly doubled since the introduction of ERP in 1998 as vehicle popu- lation increased over the last 12 years.