Report summary Express Lanes Reliability Measures Task Work Order 19 prepared for Florida Department of Transportation prepared by Cambridge Systematics, Inc
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- 2.5HOT Lanes vs. ETLs
- HOT Lanes
- Express Toll Lanes
- 3.0Data Sources, Performance Measures, and Indices
2.4RevenueAnother area of performance measurement for ELs is revenue. Both gross and net revenue are important to the success of maintaining and possibly expanding an EL system. Each EL system has a different objective when it comes to revenue. Generally, ELs are viewed as a management tool and revenue is not the priority; although the system should garner sufficient revenue as to cover cost of operations. Toll setting to maximize revenue may have an adverse effect on the overall system performance. If the tolls are set too high, traffic will avoid the ELs. If traffic avoids using the ELs, the travel time/speed performance may look good in the ELs, but much worse in the GP lanes. Therefore, the toll pricing objectives should be examined if ELs are not meeting the desired performance targets. 2.5HOT Lanes vs. ETLsWithin the FHWA’s Priced Managed Lane Guide, there are a number of different terminologies used to define the types of managed lanes where pricing is used to control access and performance. The two definitions within the guide that are closest to what Florida is proposing as ELs are HOT lanes and ETLs. HOT LanesHOT lanes use price, occupancy, and access restrictions to manage the number of vehicles traveling on them, thereby, maintaining free-flow traffic conditions, even during peak travel periods. Typically, qualifying HOVs may use these limited-access highway lanes for free or at a reduced cost. Motorists in vehicles that do not meet passenger occupancy requirements may choose between the GP lanes or paying for premium conditions in the HOT lanes. HOT lanes use electronic toll collection and traffic information systems that make it possible to provide variable, real-time toll pricing for non-HOV vehicles. Motorists receive information on price levels and travel conditions via variable message signs, providing potential users with information they need to decide whether to use the HOT lanes or the GP lanes. Express Toll LanesETLs are dedicated managed lanes within highway rights of way that motorists may use by paying a variably priced toll. They also are typically located next to the median to encourage travel for longer distance trips. Unlike HOT lanes, ETLs charge all vehicles – including HOVs – for passage. In some cases, they may also offer discounted passage for HOVs, but ETLs do not incentivize ride sharing to the extent that HOT lanes do. Enforcement is much simpler and less costly than HOT lanes because there is no need to enforce vehicle occupancy. ETL concepts are also attractive to transportation agencies that want to use toll revenues to cover the cost of new construction and operation. Interstate 95 is a critical corridor serving passenger vehicles, freight, and transit in southeast Florida. This is a heavily congested corridor in Miami-Dade, where typically travelers experience peak-period travel times that are twice as long as free-flow travel times. With limited right of way, there are few options for adding capacity the traditional way through new lane construction. FDOT District 6 sought intelligent transportation systems (ITS) remedies to improve the mobility along I 95 in Miami-Dade County. The most monumental of these solutions was the creation of the ELs. The way express lanes are being planned and constructed in Florida makes them a facility within a facility. These facilities are either a conversion of an existing lane(s) or the construction of new lane(s) on the left-hand side of the GP lanes. The ELs in Miami-Dade County were created by converting an existing HOV lane into two toll lanes. The ELs are separated from the GP lanes by plastic delineators. In order to access the ELs, traffic must weave across the GP lanes to get to or from the ELs. The exception is if a direct ramp connection to the ELs is provided. In most cases, the access connections being planned are at-grade. The dynamic congestion pricing methodology used for 95 Express adjusts tolls based on traffic conditions in the ELs only and not on conditions in the GP lanes. The goal is to keep traffic moving in the ELs at 45 mph 90 percent of the time during peak periods. ELs may be used free of charge by registered carpools of three or more persons; registered hybrid vehicles; registered South Florida vanpools; motorcycles; and transit, school, and Greyhound buses. Trucks are prohibited. 3.0Data Sources, Performance Measures, and Indices3.1Data SourcesFDOT has acquired the National Performance Measurement Research Data Set (NPMRDS) data through a licensing agreement with the FHWA. The NPMRDS data includes travel speeds for the interstate system dating to October 2011. This data provides five-minute travel times of passenger cars, trucks, and all vehicles1 on Traffic Message Code (TMC) links collected by probe vehicles. TMC links are a probe data vendor industry standard definition of roadway segments. Because an express lane system is a separate facility within a facility, it should also have its own TMC links. The NPMRDS data does not provide separate speed and travel time data for the ELs TMCs. Currently, the NPMRDS is not a viable data source for reporting on EL performance. On December 5 2013, Cambridge Systematics obtained access to the historic HERE data through the FDOT ITS Office. The ITS HERE data provides more comprehensive coverage than the NPMRDS data. This data set includes all of the State Highway System (SHS), most local roads, and separate data for ELs. The EL HERE travel time and speed data is not factored in the current reporting of EL performance measures. However, if the confidence in the existing data source diminished, the ITS HERE data should be considered as a source for monitoring the performance of the ELs. This would require conflating traffic volumes to the HERE travel speed data. Conflation is a big task requiring hundreds of man hours and considerable resources. ITS detector data is a consistently utilized source of travel speed data. ITS instruments are able to capture real-time travel speeds and report travel time data in two-minute increments. This level of granularity is sufficient for performance monitoring and reporting. Because properly functioning ITS instrumentation is critical in updating price algorithms, the EL sensors are regularly serviced. A primary reason ITS sensors are not regularly used to collect volume data is because they are not maintained. However, this is not the case for the EL sensors. They have been found to be a reliable source for both volume and speed data and should be the source for travel time data on express lanes. Table 3.1 provides a comparison of the types of data sources that are available for use. NPMRDS, INRIX, and HERE data are current sources used by FDOT; TOM TOM data is also commercially available, but not commonly used. Table 3. Commercially Available Travel Time and Speed Data Sources
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