Airport Curbside and Terminal Area Roadway Operations (2010)

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

57 This chapter presents examples of commonly occurring air- port curbside and roadway operational problems and poten- tial improvement measures. Analyses and evaluations of airport curbside and terminal area roadways generally involve the following steps: 1. Identify the Problem(s)—Problem identification includes determining the causes of existing congestion, delays, imbalances in demand, and/or whether the existing (or proposed) roadway network can accommodate anticipated future requirements. 2. Document Goals and Objectives—Documenting the rele- vant goals and objectives of airport management (and other stakeholders) with respect to roadway operations is a key step in the analysis and evaluation process. The relevant objectives may include such broad categories as • Providing safe and secure operations for airport users; • Providing desired levels of customer service for airline passengers, visitors, employees, and other airport users; • Accommodating existing and future requirements; • Accommodating regional mobility needs/encouraging the use of public transportation; • Supporting regional air quality goals; • Supporting the airport’s ability to maintain or enhance airfield capacity by ensuring that changes to roadways and curbsides do not negatively affect airfield opera- tions or capacities; and • Maintaining and enhancing the net revenues generated by the airport. Detailed descriptions and definitions of goals will allow the development of airport-specific objectives that can be used to compare and evaluate alternative improvement measures. 3. Identify and Develop Potential Improvements—The potential improvement measures described in this chapter can serve as a starting point for improvements that address commonly occurring airport curbside and terminal area roadway operations. Tables 6-1 and 6-2 present commonly occurring problems and potential improvement measures for terminal area roadways and curbsides, respectively. These tables also indicate the relative benefits resulting from implementation of the improvement, although the actual benefits will vary significantly depending on the road- way configuration and nature of the problem at the specific airport. 4. Evaluate the Potential Improvements—The alternative analytical methods described in previous chapters can be used to quantify the changes expected to result from the potential improvements, to assess their advantages and dis- advantages, and to identify the preferred improvement(s). 5. Reach Consensus on the Preferred Improvement—A key step in the implementation process is to build consensus supporting the selection and implementation of the pre- ferred alternative. An evaluation process that quantifies the extent to which the potential improvement would support the stated goals and objectives of airport management (and other stakeholders) provides a foundation for achieving consensus. 6. Implement the Preferred Solution—This step could involve design and construction activities, operational improvements, or changes in airport management policies. Typical Terminal Area Roadway Problems Operational and physical problems can adversely affect the ability of terminal area roadways to accommodate traffic effi- ciently and safely. In this section, 10 types of deficiencies that may occur in an airport environment are identified. These defi- ciencies typically can result in queues or delays; many airport roadways exhibit one or more of the deficiencies described in this section. C H A P T E R 6 Improving Airport Curbside and Terminal Area Roadway Operations

58 Table 6-1. Typical terminal area roadway problems and improvement measures. Table 6-2. Typical curbside roadway problems and improvement measures. Note: Relative success of an improvement measure may vary significantly depending upon factors unique to an individual airport. Note: Relative success of an improvement measure may vary significantly depending upon factors unique to an individual airport.

Insufficient Roadway Capacity A roadway has insufficient capacity if, during the analysis period, the roadway operates at LOS D or worse (see Chapters 4 and 5 for definitions of levels of service). LOS D refers to con- gested roadways and is an unacceptable basis for planning air- port roadways. Specific implications of insufficient roadway capacity include (1) congested roadway sections with queues extending to upstream roadways, (2) motorists experiencing frequent congestion and significant delays, and (3) a generally unsatisfactory airport experience. Insufficient Merging Capacity Insufficient merging capacity results when a roadway does not provide sufficient capacity at points where two or more streams of traffic combine into a single stream. This deficiency results in roadway delays, congestion, and traffic queues extending back from the merge point. Merge segment capac- ity is determined by the volume of entering traffic, operating speeds, and number of lanes upstream and downstream. Inadequate Weaving Distance Inadequate weaving distance results when a roadway does not provide sufficient length or travel lanes to accommodate the traffic volumes at the point where two or more streams of traffic traveling in the same direction cross or merge, causing vehicles to decelerate (or stop) while waiting for adequate gaps in the traffic stream. This deficiency results in (1) vehicle delays and queues, (2) higher accident rates, and (3) slower speeds and flow rates. Factors influencing required weaving dis- tances are operating speeds, traffic volumes (merging, weaving, and flowing through the segment), and the number of lanes that vehicles must cross to complete the desired maneuver. Lane Imbalance Lane imbalance results when a roadway segment, before a diverge or after a merge, contains two (or more) fewer lanes than the combined total number of lanes entering or exiting the segment. For example, at a point where two three-lane roadways merge, the downstream segment must consist of at least five lanes or a lane imbalance will result. At a point where a roadway diverges into two two-lane roadways, the upstream segment (prior to the diverge) must consist of at least three lanes. A lane imbalance can cause increased delays, sudden diverge or weave maneuvers, increases in the required roadway weaving distances (e.g., the number of lanes to be crossed), and higher accident rates. Proper lane balance helps reduce or avoid forced merges, weaves, and sudden maneuvers. For example, when a two-lane roadway splits or diverges into two roadways, lane balance can be achieved by providing a third lane prior to the diverge point that allows motorists access to either of the two downstream roadways (e.g., an “either-or” lane) or by extending a lane downstream past the merge/diverge point and then dropping the lane using design guidelines appropriate for the roadway speed (e.g., taper distances). Directional Information Overload Directional or wayfinding information overload occurs when more information (or decisions) is presented to a motorist than the motorist can read, comprehend, and react to in the available time (and distance). This overload causes driv- ers to weave suddenly, miss exits, make sudden or erroneous movements, or, in extreme cases, stop in the roadway (or on the shoulder) to read the signage. It is desirable to avoid presenting more than two decisions or more than four lines of text on each directional sign. If more than four lines of text must be used on one sign at an airport, it is necessary to prioritize the information and avoid using unfamiliar or inconsistent terms. Insufficient Decision-Making Distance Insufficient decision-making distance is defined as an insuf- ficient distance (or time) for motorists to read, comprehend, and react to information regarding a decision that must be made. This situation causes drivers to weave suddenly, miss exits, make wrong turns, or, in extreme cases, stop in the road- way to read the message or back up to the decision point. Fac- tors contributing to providing the necessary decision-making distance include travel speed, message content, visibility of the decision point, and visibility of the directional signage. Insufficient Queuing Space Queuing space represents the area required to accommodate vehicles stopped at an entrance (or exit) to a parking lot or other facility, traffic signal or turn lane, or vehicle inspection area so that vehicles in the queue do not interfere with traffic flow on the adjacent roadway or travel lanes. For example, a parking facility entrance should have sufficient space to accom- modate vehicles queuing at the ticket issuing machines with- out having the queue extend onto the adjacent roadway. (See Figure 6-1.) Unexpected Lane Drops/Inadequate Taper Lengths Unexpected lane drops and inadequate taper lengths (the distance required to introduce a new lane or drop an exist- ing lane) result when a through lane unexpectedly ends and motorists are required to unexpectedly merge quickly into an adjacent lane. Required taper lengths, which vary according to 59

roadway operating speeds, are intended to allow sufficient distance for lane channelization and vehicle merging. Un- expected lane drops reduce roadway capacity and travel speeds, as motorists who become “trapped” in a lane are required to merge quickly (interfering with the flow of other vehicles in adjacent lanes). Unexpected Transition from High-Speed to Low-Speed Roadway Environment Some motorists do not realize they need to slow down as they exit from a regional roadway (which may operate at more than 55 mph) and approach a terminal area roadway (which may operate at less than 30 mph) until they encounter a sharp curve at the entrance to the terminal or vehicles stopped in the roadway. This situation is particularly true at airports where a limited access highway, designed to freeway stan- dards and capable of accommodating freeway speeds, connects the regional roadway network with the terminal area roadways (see Figure 6-2). Motorists may be provided few visual clues that the driving environment is changing and requires them to decelerate. Additionally, speed limit signs may get lost among the many other signs and distractions associated with roadways approaching an airport terminal. This transition is compounded by the reduction in roadway capacity that accompanies the reduction in speed: a three-lane access roadway operating at 55 mph (or more) has more capac- ity than a three-lane curbside roadway operating at 30 mph (or less). If the traffic volume on the access roadway is the same as that on the curbside roadway, it is necessary to provide addi- tional travel lanes on the curbside roadway to compensate for the reduction in travel speed. Often, the volumes are not con- stant, as some traffic exits for non-terminal area destinations, such as parking and rental car facilities. Missing Movements Missing movements are defined as a desired travel path or traffic movement that is not provided on an airport roadway network. If a movement is missing, motorists may need to exit and re-enter the airport or travel extra distance. For example, at most major airports, motorists can proceed directly from the enplaning curbside to short-duration parking and from short- duration parking to the deplaning curbside without leaving the terminal area. The absence of roadway segments provid- ing these direct movements increases traffic demand on the return-to-terminal roadways and vehicle miles of travel. Potential Terminal Area Roadway Improvement Measures Potential improvements to terminal area roadway opera- tions are presented in the following categories: • Physical improvements, • Operational measures, and • Airport policies. 60 Figure 6-1. Insufficient queuing space at parking entry at Tulsa International Airport. Figure 6-2. Transition from high-speed to low-speed airport roadways at Baltimore/Washington International Thurgood Marshall Airport.

A general planning principle for the design and operation of airport roadways is to separate traffic generated by airline passengers and visitors from that generated by employees, air cargo, and services or deliveries. At airports with multi- ple entrances/exits, this can be accomplished by having one entry/exit serving airline passengers and the other serving non- passenger traffic. At airports with one access road, this can be accomplished by having nonpassenger traffic exit the access roadway well in advance of the terminal area, and by provid- ing a separate service roadway for these vehicles. Appendix B (Bibliography) lists selected references regarding the design and improvement of roadways and intersections and relevant design standards and guidelines relevant to air- ports. These references should be reviewed prior to implement- ing any roadway improvement, particularly those that require the design of new roadways or modification or reconfiguration of the layout of existing roadways. Potential Physical Improvements to Enhance Roadway Operations Widen Roadways Additional roadway capacity can result from the following: • Constructing new lane(s). Additional lanes can be con- structed if sufficient available right of way is clear (or if it can be cleared) of obstacles, such as existing or proposed build- ings, underground utilities, aviation limit lines (where FAA restrictions govern acceptable land uses), or other fixed obstacles. Construction costs and schedules are a function of the roadway alignment, extent and type of construction, obstacles to be relocated (if any), need to maintain and pro- tect other vehicular and pedestrian traffic during construc- tion, and other factors. • Reconfiguring existing lanes. Additional lanes can be cre- ated by reducing the widths of existing roadway lanes to form additional lanes. For example, five lanes can be cre- ated on an existing four-lane roadway by reducing lane widths (e.g., from 13 feet or 12 feet to 11 feet or 10 feet) and by simultaneously reducing the width of, or converting, roadway shoulders or paved gutter strips into travel lanes. Unless existing drainage structures must be replaced or relocated, the cost of such reconfiguration is very low. • Lengthening tapers/correcting lane imbalances. Roadway construction is required to correct inadequate roadway tapers or lane imbalances. The length of a roadway taper depends on the posted speed. For example, a 250-foot-long taper is required on a 35 mph roadway to add (or end) a 12-foot-wide travel lane. Providing the required lane bal- ance may require construction of a full lane (upstream or downstream) for a longer distance. Highway design guides listed in Appendix B, including those published by AASHTO, provide additional information on this topic. • Adding exclusive left- or right-turn lanes. The capacity of at-grade intersections, particularly signalized intersections, can be improved by providing exclusive left-turn lanes (thereby eliminating conflicting traffic movements from a signal phase) or adding free-flow right-turn lanes. Reconfigure Roadways • Eliminating three-way decision points. It may be possible to eliminate a three-way decision point without requiring major roadway reconstruction, by moving one of the deci- sion points upstream and thereby converting the three-way decision point into two separate two-way decision points, which is preferable and easier for motorists. • Lengthening weaving area. It may be possible to improve an unacceptable weaving operation by closing one exit from the weaving area and directing traffic to a subsequent down- stream exit leading to the same destination. For example, at Seattle-Tacoma International Airport, traffic operations on a return-to-terminal roadway were improved by directing recirculating traffic toward the airport exit and then to a path that leads back to the terminal, thereby extending the length of the weaving area. At Los Angeles International Airport, a movable gate arm is used to close a roadway to traffic on the busiest days of the year, requiring vehicles to follow a slightly longer path, but extending the length of the weaving area. Such improvements can be implemented for minimal cost (e.g., replacing a roadway directional sign and installing a barrier, if necessary). • Improving queuing space. Queuing space can be improved by either providing additional storage space or increasing flow rates through the point of constraint. For example at the entry or exit of a parking facility, queuing space can be increased (1) by relocating the gate arms at the entry or con- trol booths at the exit plaza to provide additional storage space or (2) by increasing traffic flow rates at the control point by replacing the existing access control technology (e.g., replacing an existing ticket issuing machine with a card reader recognizing employee parking badges, or an automatic vehicle identification [AVI] transponder on commercial ground transportation vehicles). For example, with use of a credit card in/credit card out parking access control system, more vehicles can be processed per lane than with a cashier, and the need to print and issue parking tickets may be reduced or potentially eliminated. Improve Roadway Wayfinding Signs It may be possible to improve roadway guide signs by replacing complex, existing signs with simpler signs that can 61

be more easily understood by motorists. This can be accom- plished by attempting to simplify and prioritize the message content, reviewing the text and font, and using standard phraseology where possible. The use of dynamic message signs may also be helpful in certain instances (e.g., parking controls and space availability). Construct and Operate Traffic Operations Center At airports with complex roadway networks and multiple parking facilities, it may be possible to improve traffic flows by constructing and operating a traffic operations center, simi- lar to those in many large urban areas (see Figure 6-3). Using video cameras, traffic detectors, and other technologies, the traffic operations center allows airport staff to monitor air- portwide traffic operations, direct airport traffic officers to congestion points, close or open parking facilities or road- ways, change advisory signs, and perform other operations to improve the flow of traffic. Potential Operational Measures to Enhance Roadway Operations Speed Reduction Measures It may be necessary to encourage motorists to decelerate as they approach the terminal area, particularly at airports where a limited access highway connects the regional roadway net- work with the terminal area roadways. Measures to encourage motorists to obey posted speed lim- its and slow down as they approach the terminal area include • Pavement texture. Contrasting pavement textures (e.g., brick, cobblestone, or gravel textures) can be cast into strips of concrete pavement to create a warning signal (i.e., a rum- ble strip) for motorists as they approach a slow-speed area. It is possible to increase the frequency and volume of the warning signal by reducing the distance between successive strips. • Dynamic warning signs. Radar-activated speed limit signs can be installed to detect the speed of approaching vehicles and indicate to drivers how fast they are traveling. For vehicles exceeding the posted speed limit, the display could flash red. • Automatically activated pedestrian signals. Pedestrians crossing a roadway can automatically activate signals embed- ded in the roadway pavement. • Enforcement. Police enforcement measures and tools that are commonly and frequently used in non-airport environ- ments can be used to enforce posted speeds, including park- ing police vehicles in a visible location. Transportation Demand Management When used in an urban or regional setting, transportation demand management (TDM) measures are used to discourage single-occupant, private vehicle trips by promoting ride- sharing or the use of public transit, and to encourage motorists to drive outside peak hours. At airports, the most productive application of TDM is to encourage airport employees to share rides or use public transit to reduce the number of vehicle trips. For example, some airport operators and other employers have established work schedules that call for employees to work 9 out of every 10 days (e.g., take every other Friday off by work- ing longer hours on other days). Other airport operators offer discounted transit passes or partially subsidize the commuting expenses of employees who agree to use transit and forego the use of parking facilities. Intelligent Transportation Systems A variety of intelligent transportation system (ITS) applica- tions are available to encourage the efficient and safe use of transportation facilities. At airports these applications include pricing mechanisms (increasing parking costs), the use of AVI and global positioning system (GPS) technologies to monitor the location and number of trips made by commercial vehi- cles or shuttle buses, and a variety of systems for distribut- ing traveler information to arriving motorists (e.g., airline schedules/delays and parking space availability). Traveler information can be distributed using the Internet, mobile tele- phones, highway advisory radios, flight information display systems (e.g., those located on deplaning curbsides or within cell phone lots), or dynamic signage presenting parking space availability information or warning overheight vehi- cles approaching areas with limited vertical clearance. 62 Figure 6-3. Transportation operations center at Frankfurt Airport.

Potential Airport Policies to Enhance Roadway Operations Promote Transit Airport operators generally encourage the use of public transportation by supporting the construction and operation of rail transit services and by promoting the use of rubber- tired public transit services. Specific actions used by airport operators to promote passenger (and employee) use of bus service include allocating the most convenient terminal curb space for bus stops, installing signs indicating bus schedules and expected waiting times, installing transit ticket vending machines at visible locations in the terminal building, provid- ing employees with a guaranteed ride home in the event of emergencies, and subsidizing selected modes to reduce the cost to passengers. Encourage Remote Terminals with Express Bus Service An example of a remote terminal is an intercept parking lot that provides scheduled, express bus service for airport passengers and employees to and from the airport terminal. By encouraging the use of efficient access modes, these ter- minals reduce the number of vehicle trips on airport road- ways. The operators of the airports serving Boston and Los Angeles subsidize remote terminals and express bus services (e.g., the Logan Express and Los Angeles Flyaway services) and similar privately operated services are provided at Kennedy, Newark Liberty, and San Francisco International Airports and LaGuardia Airport. (See Appendix B for addi- tional information.) Encourage Consolidated Rental Car Buses or Courtesy Shuttles Consolidated rental car shuttle buses used at airports that have consolidated rental car centers replace the courtesy vehi- cles operated by individual rental car companies and thereby reduce the number of vehicle trips on airport roadways. The consolidated rental car shuttle buses can be operated by a rental car industry consortium or by the airport operator (using a third-party contractor) on behalf of the rental car companies. Some airport operators have successfully encour- aged hotels/motels to operate consolidated courtesy vehicles or shuttle buses. Manage and Control Commercial Vehicle Operations Numerous measures are available to manage and control commercial ground transportation vehicle operations. These measures, which primarily affect curbside roadway operations, but may also improve other roadway operations, are described in the remainder of this chapter. Typical Curbside Roadway Problems Operational and physical problems can adversely affect the ability of airport curbside roadways to accommodate traffic safely and efficiently. Typical problems include those listed in this section. Insufficient Curbside Roadway Capacity Insufficient curbside roadway capacity exists when curbside requirements (lengths) are greater than 1.3 times the usable curbside length and/or the through lanes on a curbside roadway operate at LOS C or worse. When curbside demand exceeds available capacity, motorists experience significant delays and queues, as evidenced by high levels of double and triple parking throughout the entire curbside, which, in turn, reduces the capacity and travel speeds of the curbside roadway through lanes. As noted previously, curbside roadways must provide both adequate curbside length (stopping space) as well as adequate throughput capacities. Any deficiencies in one area will adversely affect the other. Factors that contribute to a lack of curbside roadway capacity are described in the following paragraphs. Imbalances in Demand Imbalances in curbside demand occur when the total length of curbside space available is sufficient to accommodate curb- side demand, but most of the demand occurs at, and overloads the capacity of, one segment of the total curbside area. For example, if one or more airlines on one concourse serve most of the peak-hour airline passenger activity, then curbside traf- fic will be concentrated at the doors leading to the portions of the terminal building occupied by these airlines, leaving the remainder of the curbside areas empty or underutilized. Gen- erally, it is not feasible to relocate the assigned airline ticket counter or baggage claim area locations solely to balance curb- side demand. Insufficient Number of Travel Lanes A curbside roadway that does not provide sufficient capac- ity to accommodate existing or future requirements at LOS C or better typically has an insufficient number of travel lanes. Generally, curbside roadways with four lanes or more provide sufficient capacity because two travel lanes remain available even when double parking occurs. Congestion and delays may occur frequently on curbside roadways having three lanes or 63

fewer as any double parking severely restricts through traffic. Similar restrictions also occur when vehicles are allowed to stop on the inner and outer lanes of a four-lane curbside, leav- ing only the two center lanes for through traffic. Pedestrian Crosswalks and Pedestrian Activity Pedestrians crossing a curbside roadway restrict the vol- umes of through traffic that can be accommodated. Delays caused by crosswalks are related to the volume of pedestrians walking across a curbside roadway, the proportion of time that pedestrians occupy a crosswalk (properly or improperly), and the number of crosswalks located at curbside. Traffic flows and safety also can be adversely affected by pedestrians stepping into the roadway to avoid columns or other obsta- cles, hail vehicles, or board/alight from a vehicle stopped in a through lane. Driveways Serving Adjacent Land Uses Driveways serving adjacent land uses (e.g., parking lots or rental car ready/return areas) may impede the flow of curbside traffic when vehicles in the lane farthest from the terminal decelerate (or accelerate) as they enter (or exit) the driveways serving the adjacent land uses. Vehicle queues formed at the entrances to these land uses may extend back onto the curb- side roadways. Insufficient Curb Length Insufficient curb lengths result from curbside demand that is greater than 1.3 times the usable curbside length, which also occurs when there is significant double parking. Inefficient Allocation of Curb Space Inefficient allocation of curb space results where the total available space is adequate to accommodate demand, but the available space has been divided into (or allocated among) many categories of ground transportation services such that some categories are allocated more curb space than required while others are not allocated enough. This situation may occur when curb space is allocated to vehicles that rarely serve the airport (e.g., charter buses), demands have changed as a result of the introduction of new services, or the space has been broken into small segments that do not correspond to the operational or maneuverability needs of the assigned class of ground transportation service. Similarly, inefficient allocation of curb space results when the amount of curb associated with a specific airline does not match the relative share of passenger traffic served by that airline. Unusable Curbside Roadway Geometry Unusable curbside roadway geometries exist when vehicles cannot stop to load or unload passengers because of the curved alignment of the roadway, narrow sidewalks, or other physical obstructions. Many terminals have curved curbside road- ways, but generally the radii of these roads are very large and motorists do not perceive that they have stopped along a curvi- linear section. However, some curbside roadways have small radii or tight curves that hinder a motorist’s ability to park par- allel to the sidewalk or to enter or exit this space. Motorists may be unable to park adjacent to curbsides having narrow side- walks (e.g., the ends of island curbside areas) or columns (or other obstacles) adjacent to the roadways. Large bollards, which are sometimes placed on terminal building sidewalks to protect pedestrians and the terminal building from vehicles that may accidentally jump the curb, may interfere with the ability of motorists to open/close their doors or enter/exit their vehicles. Narrow sidewalks also may force pedestrians to step into the roadway (with their baggage) to bypass columns, queues of passengers formed at skycap positions, benches, or other obstacles. Excessive Dwell Times Excessive dwell times result when vehicles (either private or commercial) are allowed to remain at the curbside when not actively loading or unloading passengers. In the case of some commercial vehicle providers, excessive dwell times are per- mitted by airport rules and regulations. Excessive dwell times may reflect insufficient police presence or visibility, or permis- sive airport policies and may occur even if the dwell times of most vehicles are within reasonable limits and fewer than 10% of vehicles remain at the curbside for excessive periods. Potential Curbside Roadway Improvement Measures Potential curbside roadway improvements to enhance operations are presented for the following categories: • Physical improvements, • Operational measures, and • Policy measures. Physical Improvements to Enhance Curbside Operations Widen Curbside Roadways Additional curbside roadway capacity can be provided by the following: 64

• Adding lanes to an existing curbside roadway. Widening a roadway from four lanes to five lanes, for example, can increase through-lane capacity and allow the roadway to better accommodate double- or triple-parked vehicles as well as the interruption to through traffic caused by vehicles entering and exiting curbside lanes. • Constructing new curbside roadway(s) and center island curbside area. Constructing a second (or third) roadway parallel to an existing curbside roadway can increase (almost double) the capacity of a curbside area. The amount of addi- tional capacity realized from such an improvement is a func- tion of the resulting effective length and the allocation of space. Private vehicle motorists are reluctant to use curb- sides perceived as being less convenient. Customer service and the attractiveness of a curbside waiting area can be enhanced by providing weather protection for passengers at curbside areas not located immediately adjacent to a termi- nal building or under a building canopy. Similarly, shelters with benches can improve the service levels for customers waiting for scheduled transportation services or courtesy vehicles. • Constructing a new bypass roadway. At airports with mul- tiple terminals, construction of a bypass roadway can reduce the volume of through traffic on a curbside roadway and increase the level of service. Lengthen Curbside Roadway It may be possible to extend the length of a curbside area past the terminal building façade if conveniently located doorways are available to serve motorists using these extensions. Com- mercial vehicles can be assigned to extended curbside areas, particularly infrequent users of the airport, such as charter vehicles. Private vehicle motorists prefer to stop in front of the terminal building and are unlikely to use extended curbside areas unless they are perceived as convenient. Construct Additional Curbside Level At airports with a single-level curbside roadway serving a multilevel terminal building, additional capacity can be pro- vided by constructing a new elevated curbside roadway. For example, in 1984, a second-level curbside roadway was con- structed above the then single-level curbside roadway at Los Angeles International Airport. A second-level curbside road- way also was added at Hartford’s Bradley International Air- port. Such a capacity enhancement requires that the terminal building either have multiple levels or be modified concur- rently with the roadway expansion. Generally, it is considered impractical to add capacity by constructing a two-level curbside to serve a single-level build- ing or a three-level curbside to serve a two-level terminal building because passenger terminal building layouts dictate curbside roadway designs (rather than vice versa). A roadway that does not match a building’s floor elevation would require separate vertical circulation elements to allow passengers to transition between the terminal building and roadway. Con- sequently, the decision to construct a second-level curbside roadway, for example, is driven by the design of a new termi- nal building or planned expansion of an existing terminal building. Remove Pedestrian Crosswalks Additional capacity can result from the following: • Merging crosswalks. Roadway traffic operations can be improved by merging crosswalks to reduce the number of locations where vehicular traffic flow is interrupted. Such changes may reduce the level of service for some pedestrians, because they would be required to walk farther. In the extreme case, it may be necessary to install fences or barriers to discourage jaywalking, and potentially to use traffic sig- nals or traffic control officers to control pedestrian traffic. • Relocating pedestrian traffic. Roadway traffic operations can be improved and pedestrian levels of safety enhanced by constructing pedestrian bridges above, or tunnels beneath, a curbside roadway and removing at-grade pedestrian cross- walks (see Figure 6-4). Since the path would require pedes- trians to change grades (while transporting baggage), it would be necessary to make the new path more attractive than an alternative at-grade path, or to construct fences or other barriers to discourage passengers from continuing to cross the curbside roadway at grade. • Controlling pedestrian activity. Pedestrians crossing a roadway can automatically activate signals embedded in 65 Figure 6-4. Elevated pedestrian bridge at Los Angeles International Airport.

the roadway pavement to improve pedestrian safety and control pedestrian and vehicular traffic flows. Provide Alternative Passenger Pickup/Drop-Off Areas Alternative or supplemental curb space can be developed to augment the capacity of the areas adjacent to the terminal building. Examples of alternative passenger pickup or drop- off areas include • Curb space within a parking garage. Several airports have curbside areas within parking garages allocated for commer- cial ground transportation or private vehicles, or space adja- cent to the garage that is not directly accessible from a terminal building. These areas are particularly attractive when grade-separated pedestrian access is provided between the terminal and the parking structure. Examples include – A curbside roadway located within a garage allocated to commercial vehicles (e.g., Seattle-Tacoma International Airport); – A commercial vehicle passenger pickup area/curbside space located at a close-in parking structure away from the terminal (e.g., Indianapolis International Airport); and – A curbside roadway located within a parking garage allocated to private vehicles (e.g., Lambert-St. Louis International, Salt Lake City International, and LaGuardia) (see Figure 6-5). • Commercial vehicle courtyards. A commercial vehicle courtyard is a parking area adjacent to or near the terminal building reserved for use by commercial vehicles picking up or dropping off airline passengers. These areas are referred to by various terms, such as “ground transportation center” or “intermodal center.” Courtyards and dedicated curbside roadways can augment the capacity of a curbside area (or relieve congestion) by providing additional passenger pickup (or drop-off) areas. These areas can benefit commer- cial vehicle operations as the operators need not maneuver through private vehicle traffic to enter and exit their assigned spaces, and are allowed longer dwell times in these areas. Commercial vehicle courtyards are provided at the air- ports serving Atlanta, Fort Lauderdale, Newark, San Fran- cisco, and Tampa. The airports serving Denver, Nashville, Orlando, San Francisco, Toronto, and Washington, D.C. (Dulles) have three-level curbside areas (see Figure 6-6) with one entire level reserved for commercial vehicle use. Although these commercial vehicle areas operate in a man- ner similar to courtyards, they are not considered potential curbside improvement measures because, as noted earlier, their implementation requires the appropriate terminal building configuration. • Remote curbsides. At Chicago O’Hare International Air- port, commercial vehicles pick up and drop off passengers on a roadway located between the on-airport hotel and the central parking garage. Underground tunnels link this site (the Transportation Center) to the terminal buildings. An enclosed and heated/air conditioned passenger waiting area with seating is provided in the parking garage adjacent to the Transportation Center. At San Francisco Inter- national Airport, a supplemental remote curbside is avail- able to serve the drivers of private vehicles meeting arriving passengers. This supplemental curbside is located adjacent to a remotely located Consolidated Rental Car Facility and automated people mover station. The station, intended primarily for use by rental car customers, allows passengers to easily travel to the supplemental remote curbside. 66 Figure 6-5. Supplemental curbside inside parking structure at Salt Lake City International Airport. Figure 6-6. Three-level curbside at San Francisco International Airport.

Operational Measures to Enhance Curbside Capacity Reduce Curbside Requirements The following measures are intended to enhance curbside capacity for certain vehicle modes by reducing the amount of curbside required by other vehicles. • Restrict curbside use to authorized vehicles. The use of curbside areas (or portions of curbside areas) can be restricted to authorized commercial ground transportation vehicles. Numerous airport operators limit the use of com- mercial vehicle lanes by posting “authorized vehicles only” signs at the entrance to these lanes, or by installing gate arms activated by AVI transponders, proximity cards, or other devices. Unauthorized commercial vehicles (e.g., those without airport permits or AVI tags) cannot gain access to these areas. As noted in subsequent paragraphs, commercial vehicles may be required to abide by other airport regula- tions limiting their use of curbside roadway areas. • Develop cell phone lot. A cell phone lot (also referred to as a park and call lot) is a free parking area located away from the terminal where a motorist picking up a deplaning pas- senger can wait until the passenger has gotten off the plane, claimed baggage, arrived at the curbside, and called the motorist to indicate their arrival at the curb. Cell phone lots enable motorists to use curbside areas efficiently because (1) the airline passengers can tell the drivers exactly where they are (or will be) located at the curb, (2) if the curbside area is congested, the passenger and motorist can arrange an alternate pickup location (e.g., a different curbside area), and (3) the motorist will avoid being forced to leave the ter- minal area and possibly recirculate multiple times (e.g., if the airline passenger was not ready when the motorist first arrived at the curbside). The operators of some airports (e.g., those serving Phoenix and Salt Lake City) have placed out- door flight information display monitors or dynamic signs presenting this information within cell phone lots to assist waiting drivers (see Figure 6-7). At other airports (e.g., Tampa International Airport), such signs have been installed on the deplaning level curbside to aid waiting motorists and encourage them to exit the curbside when flights are delayed (see Figure 6-8). Several airport opera- tors have or are developing on-airport convenience stores or retail centers where the parking area can be used as a cell phone lot (e.g., Denver International Airport). • Provide attractive or free short-term parking. Motorists can be encouraged to park in a conveniently located short- term parking lot if they are confident that they can easily find an empty, reasonably priced space. Encouraging motorists to park while accompanying an airline passenger to/from the terminal rather than using the curbside areas reduces curbside requirements. The extent of the reduced demand is a function of the proportion of motorists attracted to park- ing who would not have otherwise parked. To encourage the use of short-term parking, some airport operators offer free parking for up to 30 minutes. However, analyses of before- and-after data at Seattle-Tacoma International Airport indi- cate that 30 minutes of free parking had a negligible effect on curbside requirements. • Encourage the use of public transit. As described in the previous section on Potential Airport Policies to Enhance Roadway Operations, by encouraging airline passengers to use public transit, airport operators can reduce airport road- way and curbside traffic. Numerous methods are available to encourage the use of public transit, including allocating preferential curb space to publicly or privately operated public transit services. 67 Figure 6-7. Flight information display system at cell phone lot at Salt Lake City International Airport. Figure 6-8. Flight information display system at deplaning curbside at Tampa International Airport.

Reduce the Speed of Curbside Roadway Traffic Measures to encourage motorists on curbside roadways to operate safely or to slow down and watch for pedestrians cross- ing the roadway include the following (in addition to those described above under roadway operations): • Use speed humps and speed platforms or tables. These devices are forms of raised roadway pavements placed across a travel lane to force motorists to slow down. These devices are generally used on roadways operating at less than 25 mph. The key differences between these devices are their length and the amount of speed reduction achieved. Speed humps are 6 to 12 inches high, and about 4 to 6 feet long with a gradual sloping approach. Speed platforms or tables are flat-topped speed humps that are long enough for an entire vehicle to rest on top, and that can function as raised pedestrian crosswalks. Speed platforms can reduce traf- fic speeds, help indicate the locations of crosswalks to motorists, and minimize grade changes for disabled pedes- trians crossing the curbside roadway. It is necessary to con- firm that adequate vertical clearance will be possible prior to installing a speed hump or platform on the lower level(s) of a multilevel roadway. The use of speed bumps—raised devices 2 feet long or shorter with abrupt slopes—is strongly discouraged. • Roadway width restrictions. Narrower lanes or physical constraints on roadway widths can encourage motorists to drive slowly. Curbside roadway widths can be constrained by reducing the number of roadway lanes, or lane widths at crosswalks, the ends of median islands, and other locations. Improve Curbside Enforcement Police enforcement procedures commonly used elsewhere can be used to enforce curbside traffic operations at airports. Enforcement of dwell times and unattended vehicle prohibi- tions typically receive more attention than speeding on curbside roadways. Some airport operators contract with a tow truck operator parked at, or near, the curbside entrance to discourage motorists from leaving their vehicles unattended, remaining at the curbsides too long, or engaging in other improper behavior. Some airport operators employ traffic control officers (TCOs) rather than licensed law enforcement officers (LEOs) for curbside operations because of their effectiveness (TCOs can focus entirely on traffic control and are not dispatched to other assignments) and cost (TCO wages are typically lower than those of LEOs); thus, an airport operator can hire more TCOs than LEOs. Revise Curbside Allocation The space allocated for individual categories of ground transportation services can be revised by • Modifying the amount of space allocated. The amount of space allocated to each category of ground transportation service (including private vehicles) can be increased or decreased to respond to changes in airline passenger activity or curbside requirements, introduction of new transporta- tion services, or new airport policies. • Moving assigned spaces. The assigned space can be relo- cated to a better (or worse) location near a major exit door serving a major airline or to an inner curbside from an outer curbside. • Combining or separating spaces. The curb space allo- cated to different categories of ground transportation can be merged or separated. For example, all courtesy vehicles can be required to use a common curbside area rather than sep- arate space being allocated for the courtesy vehicles serving hotels, parking lots, and rental car companies (or these ser- vices can be separated). • Requiring single-stop operations. Improved utilization of available curb space can result from requiring commercial vehicle operators to drop off and pick up passengers at the same location (e.g., having courtesy vehicles drop off and pick up their customers on the upper level). This require- ment reduces the number of stops and amount of spaces required by these vehicles. Requiring commercial vehicles or public transit to drop off and pick up customers at a single location also reduces customer service by requiring more level changes and longer walks. • Using off-peak areas. Improved utilization of existing curb space can result from requiring commercial vehicle opera- tors to drop off and pick up passengers at underutilized areas of the terminal building. An example would be requir- ing commercial vehicles to drop off customers at the bag- gage claim area during the enplaning peak hour or to pick up passengers at the ticketing area during the deplaning peak hour. Modify Commercial Ground Transportation Vehicle Operations Airport operators can establish ground transportation rules and regulations that govern how, where, and when a ground transportation vehicle operator is allowed to use air- port roadways. The following section provides additional information. Potential Airport Policies to Improve Curbside Operations Airport operators can require commercial vehicle opera- tors picking up airline passengers to abide by airport rules and regulations governing (1) the roadways each operator may use, (2) where commercial vehicle operators are allowed to stop on the airport roadways to drop off or pick up passen- 68

gers, (3) the maximum dwell times permitted, (4) the speed limits and other restrictions they must obey, and (5) the fees they must pay to operate on the airport. Examples of these policies and regulations are provided below. Airport operators may require the operators of commer- cial ground transportation services to pay a variety of fees to recover costs or manage demand. These fees include those charged on an annual or monthly basis per company or per vehicle, and cost-recovery fees typically calculated based on the ground transportation operator’s volume of vehicle trips or volume of airport-related business. Demand management fees include fees penalizing operators that remain in the curb- side area in excess of a specified maximum dwell time, exceed a daily or monthly limit on the number of courtesy vehicle trips, and violate established minimum time intervals between successive courtesy vehicles they control. Airport operators may use these fees to improve curbside traffic oper- ations, discourage unnecessary trips—including those made by an operator seeking to advertise its product or service (i.e., operating moving billboards rather than transporting customers)—reduce vehicle emissions and improve air qual- ity by encouraging the use of alternative fuel vehicles or con- solidated shuttle vehicles through the use of discounted fees, or achieve other objectives of the airport operator. 69