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Chapter 2. Inputs to the Scheduling Process 2.2 External Factors passenger load The number of passengers carried The first four requirements have the word "knowledge" in them. This is a reminder that there on one or more vehicles at any is no substitute for knowing your individual transit agency's or company's policies, service point on a route. Of particular budgets, goals and objectives, and the areas served. These underlie all aspects of schedule interest is the maximum passenger development. This manual assumes you are familiar with your agency's policies as well as your load on a route or segment. routes and how they interact with each other. A detailed working knowledge of the transit sys- tem is one of the most fundamental requirements for a scheduler. This understanding assists in making the many value judgments that are required during the scheduling process. service standards Performance requirements ex- Fieldwork is very helpful in keeping your knowledge of your system up to date. The kinds of pressed in system policies. Service things that you should look for when you are out in the field include: how adequate is the standards are normally established running time; what do the passenger loads look like at various points along the route; where in areas such as cost efficiency are places that cause potential delays; is there a better place to turn around at the end of the (cost per unit of service), service route; are the number of wheelchair boardings greater than what would be considered average effectiveness (boardings per unit for other routes on the system. Getting out of the office once in a while also is a good change of of service), cost effectiveness (cost pace from the routine. As Yogi Berra once said, "You can observe a lot by watching." and subsidy ratios), passenger loading, and schedule adherence. The last three decades of government financial assistance have brought a uniformity of prac- Many agencies also have service tices to most transit organizations. This has served to produce documents that set standards policies that guide the development for schedulers. Such documents as the Five Year Service Plan and its annual updates establish of routes and schedules. Also or update route design criteria and service standards. A financial plan goes hand in hand with known as "service guidelines." the Five Year Service Plan. It may call for expansion of service, service reductions, or both at the same time, depending on the goals of the service plan and the realities of the available funding. Sometimes circumstances will change quickly during a budget year, requiring major branch changes to the service. The scheduler must be aware of the general direction of the transit One of two or more outer route system; these strategic reports are a useful source of information. segments served by a single route. 2.3 Inputs to the Scheduling Process Union Contracts--Collective Bargaining Agreements Union contracts or collective bargaining agreements carry specific requirements that affect how service is scheduled, blocked, and cut into driver runs. Even systems that have no union tend to have their own rules that have developed over time. Much will be said later about labor provisions, but we assume that you have read the contract and have highlighted those sections pertinent to the scheduler. 2-4

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Chapter 2. Inputs to the Scheduling Process Beyond the union contract are agency scheduling practices or preferences. Questions such as "do we prefer to avoid interlining?", "is our operating practice to avoid street reliefs after PM?", or "do we prefer not to schedule runs too close to maximum allowable spread time?" cover typical non-contract issues. In most cases there are many preferences and practices not covered in the labor contract, and these need to be understood. Route Design Depending upon the structure and size of your agency, as a scheduler you may or may not be responsible for (or have input into) design of routes. Either way, it is important to understand at least the basic principles in route design as they significantly affect the entire scheduling process. The extent of route changes varies widely from system to system. The route network may remain static or may be subject to varying levels of change. While schedulers overwhelm- ingly work on existing routes, they will be called upon at some point to build a schedule on an entirely new route and may be expected to add their expertise to the final design of the route. Service planners can plan routes that meet their exacting criteria, but it is up to the scheduler to make the route work operationally. An ongoing dialogue between schedulers and service The branch example above has two planners is necessary to develop routes and schedules that meet an agency's objectives. branches at its eastern (top) end: via An important element of making a route work operationally is running time. The scheduler's Braddock Ave. and via Springfield goal is to find the happy medium between too much and too little scheduled running time to Blvd. ensure reliability and efficiency in daily operations. This will be discussed in much greater detail in subsequent portions of the manual. Practical concerns such as identifying restroom opportu- headway nities at the ends of routes are also important in route design. The interval of time between two vehicles running in the same direction Route design also encompasses certain elements that either keep the route simple or add on the same route, usually expressed complexity. Some of these are: in minutes. See also "frequency." Branches Frequency is the inverse of headway: a headway of 10 minutes is equivalent Do we allow for one or more branch routings, normally at the outer end of the route? If so are to a frequency of one bus every ten the branches of equal length? Unequal branch lengths can become a source of inefficiency in minutes or six buses per hour. a schedule, particularly at wide headways, such as minutes or longer. The route on the left has two branches of equal length. The common portion of a route with branches is the trunk. Branches also affect the time spent on basic route definition tasks in scheduling packages, trunk which need high levels of accuracy for downstream systems. The common portion of a route with branches; more broadly, a section of a corridor served by multiple routes or trip types. 2-5

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Chapter 2. Inputs to the Scheduling Process Route Deviations These may incorporate different paths in the middle of the route, either as an alternating service pattern (the route above on the right is an example), as occasional trips (e.g., serving a school at bell times), or as time of day based service patterns (e.g., deviating into a shopping center during open hours). These may be combined with branches, which can further compli- cate the schedule, particularly if the scheduler mixes and matches the alternate trips with the branch trips. Short Turns These are points were the service ends short of the end of the route. These points may be selected by schedulers or planners and should ideally be chosen at a point that is some multiple of the running time and headway, unless interlining is allowed to offset. Otherwise, layover that is longer than necessary can result. They also ideally are at a point where on-board rider- ship is half or less than the number the schedule was designed to handle at the peak load point to avoid overloads on long trips. The turnback should be at a place where the bus can This route deviation example has take layover without obstructing traffic and where it can easily turn around for the return trip. a mid-route deviation, with trips Finally, a short turn should be instituted only if it reduces peak bus requirements for the route. alternating via Utopia Pkwy and We will give an illustrative example of what must be considered in scheduling turnbacks when Francis Lewis/Willets Point Blvds. we examine more complicated schedules later in this manual. Below is an example of a route with short turns in both directions. The solid line shows the short turn "core" route between the turnback locations, while the dotted lines show the full route. A trip that terminates at an interme- diate point instead of traveling the full length of the route. Short turning is frequently used to add capacity to a specific segment of the route. turnback The location where a short turn trip turns around to begin service in the opposite direction. An example of a route with short turns in both directions. interlining The solid line shows the "core" The use of the same vehicle on route between the turnback a block operating on more than locations, while the dotted one route with the same operator, lines show the full route. without returning to the garage during route changes. 2-6

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Chapter 2. Inputs to the Scheduling Process bus rapid transit (BRT) Loops A form of bus service that, through These can cover the outer or inner end of a route, or the whole route itself can be a loop, improvements to infrastructure, either in one direction or bi-directional. Large loops at the ends of a route have the advantage vehicles and scheduling, is of service to a larger area with just one route, but can cause long out-of-direction passenger intended to enhance service quality movements. Loops are also a headache for the scheduler. Where to put the layover? Wherever compared to an ordinary bus line. you place it--before, after, or in the middle of the loop--someone riding in the "wrong" direc- Features may include exclusive tion will have to sit on the bus during the layover. One way around this dilemma is to schedule right-of-way, signal priority, widely all layover time at the non-loop end of a looped route. spaced stops, higher capacity vehicles with special branding, Express, Limited, or Bus Rapid Transit (BRT) versus Local Operation stations, headway-based sched- Routes in larger cities may have enough ridership to be able to operate two classes of service ules, and off-bus fare collection. for all or part of the day. These different types of service operating on the same corridor have different stopping patterns, running times, and perhaps even time points. The complexity express service of scheduling local and express services requires an understanding of their interaction in an A service generally connecting operational sense, and will be addressed later. residential areas with activity Through-routing centers via a high-speed, non-stop route with limited stops at each end This is the process of combining routes on different sides of a central area, usually done to for collection and distribution. Park- achieve efficiencies in use of equipment, reduce the need for layover space, simplify routing and-ride lots are a common feature by reducing the number of turns required, and reduce the number of trips operating through of express service at the residential the central area. Through-routing in this manual refers to the full time operation of two routes end of the route. as a single route for all practical purposes. Interlining is defined as a random or systematic hooking of individual trips. Some systems mix up these two distinctions or see them as inter- changeable, but we will keep them separate in this manual according to the above rule to avoid limited-stop service confusion. A service typically operating on arterial streets that makes stops In addition to the design concerns noted here, a route needs to be planned at an operational only at major points along the level to check issues such as turns and clearances, to make certain that all streets shown on the route. Similar to express service, planning map are actually continuous and any bridges can support the weight of a bus. Never but without a lengthy non-stop rely solely on a map! segment. Cycle Time hooking At the risk of getting ahead of ourselves, we include cycle time here as a strong consideration in determining routing. Again we emphasize the need for the scheduler and planner to work The process of attaching the end of collaboratively to ensure all outcomes are sufficiently understood to make informed decisions. a trip in one direction to the begin- ning of a trip the other direction. A Let us provide an example--in this case a stand-alone route operating on a simple service block is a series of hooked trips. pattern of operation with low frequency and consistent running time throughout the day. If 2-7

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Chapter 2. Inputs to the Scheduling Process the running time is minutes either way and the headway is minutes, the route schedules time point efficiently. However, what if an extension of minutes is proposed? A designated location on a route Part of the decision-making process must be an understanding that the impact of the route used to control the spacing of design change will be an increase in operating costs of one vehicle. This is often not well under- vehicles along the route. As a rule, vehicles should not pass through stood at a generic planning level, where it is sometimes assumed that a % increase in route a time point either before or after length (the minutes added onto the existing ) will result in a % increase in operating cost. the specified time on the schedule. This is not so! For simple operations such as this, the cost is a step-function which increases A route may contain several time significantly each time a cycle time threshold is reached. points depending on its overall Obtaining Mileage length. As a rule of thumb, time point spacing is usually every seven The scheduler is required to calculate route distances for a range of purposes. Whether sched- to 15 minutes along a local route, uling manually or using a computerized scheduling package, mileage is used as an input at the and time points are designated route level to provide totals at a schedule level. where possible at major intersec- tions, major trip generators, and key Even if scheduling manually, mileage can be calculated using basic "off the shelf" geographic destinations. information system (GIS) mapping systems. Furthermore, simple tools such as "Google Maps" allow distances to be calculated with a high degree of accuracy and with little effort. Older through-routing methods still in use include mileage measurement from a paper map with a flexible tape measure or a map wheel and measurement in the field using vehicle odometers. A form of interlining in which a ve- hicle switches from inbound service If using a scheduling software package, mileage is an input to the program, which then au- on one route to outbound service tomatically calculates total mileage based on trip patterns and deadhead mileage. As of this on another route while continuing in writing, nearly all computer software packages also provide a built-in mapping routine which service throughout the day. allows the scheduler to input the route and its various service patterns and obtain accurate mileage from the map. The program then automatically generates total mileage for the fin- cycle time ished schedule. Equals the round trip running time plus layover time. This is also An added benefit of using the scheduling package for obtaining mileage is the fact that mile- known as "round-trip cycle time" or age between bus stops can be accurately derived. This information is much more necessary "round-trip time." now than in the past because it forms the input for such downstream applications as automatic stop announcement systems (voice annunciators). Some transit systems have the need to deadhead break mileage down by political jurisdiction, so this feature comes in handy for them as well. The time and distance that a bus The information can be obtained by the other methods mentioned earlier, but this is true needs to travel in places where it drudgery work of the type that computers were invented to relieve. In fact, automated mileage will not pick up passengers. Dead- calculation is one major improvement since the all-by-hand scheduling era. heading is typically required to get buses to and from their garage, or No matter which method is used, the information needs to be broken down for each time point- when bus operators need to travel to-time point segment, or even at a stop-to-stop level (which is then aggregated at time point-to- from one route or point to another time point and route levels). These segments can then be accumulated into service patterns, as during their scheduled work day. 2-8

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Chapter 2. Inputs to the Scheduling Process service pattern each separate way of serving a route is called. The number of trips for each service pattern can The unique sequence of stops be multiplied by mileage for that service pattern and then simply summed into a total for that associated with each type of trip on particular schedule. a route. If all trips operate from one Mileage is always divided between revenue and deadhead mileage. The former includes all end to the other on a common path miles when the bus is actually operating in passenger-carrying service. The latter is accumu- the route has one service pattern. Branches, deviations or short lated during times of operating to and from the garage or in operating out of service from one turns introduce additional service point on one route to another point, either on the same route or on another route. Deadhead patterns. Service patterns are a mileage is often broken down into garage deadhead mileage (all mileage operating to and fundamental component of schedul- from the garage as a deadhead trip) and interline deadhead mileage (all mileage on deadhead ing and provide the framework for trips that are generated as a means of linking one trip to another). Together, revenue and tracking running time, generating deadhead mileage constitute platform mileage. revenue trips, and identifying deadhead movements for the route. Geocoding Also referred to as "trip pattern," Geocoding is the process of obtaining the latitude and longitude of an exact location from a "variant," or "path." map. This approach is overkill for merely obtaining mileage for route segments, but becomes more critical when the exact locations of bus stops have to be known [typically important for downstream systems such as automatic vehicle location (AVL), automatic passenger platform time counter (APC), voice annunciation etc.]. Using GIS software or the mapping routines built into and mileage scheduling software packages, an exact lat-long fix can be obtained for every bus stop, includ- A phrase derived from the early ing multiple bus stops at major intersections. There are many uses for this information; two 20th century days when motormen examples are ( ) bus stop databases, which also store detailed information about the stop, and and conductors operated from the ( ) automated bus stop announcement systems. The latter make use of satellite technology to "platform" of a streetcar, platform know the bus' exact location along a route and its proximity to the next stop. The "next stop" time (or platform miles) includes all announcement is triggered at a certain distance from the stop. This technology is highly useful time or distance travelled when the in meeting the requirements of the Americans with Disabilities Act and would not be possible operator is operating the vehicle. without the ability to geocode the route and stops. Layover time and pull-in and pull-out time and distance are part Scheduling software with mapping capabilities has other uses that can save schedulers time. of platform time and mileage, but Many can automatically generate the most efficient routings between starting and ending report allowance and clear allow- points on a route and the garage, inclusive of updating the database containing running ance are not. Similarly, platform times and mileage. This practice must of course be tempered by an understanding of the road miles include all miles traveled network (e.g., avoiding narrow residential streets) and key congestion points. Ultimately the while the operator is operating the scheduler should review all outputs from such tools and adjust as necessary. vehicle. Service Standards Many transit systems publish service standards. These set forth, often in great detail, minimum service levels (known as policy levels) by time of day and day of week. Where demand requires 2-9

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Chapter 2. Inputs to the Scheduling Process service greater than these policy levels, the standards specify minimum and acceptable load Frequency and headway factors, which in turn determine headways. These standards can simplify some aspects of the Tip are both used to define scheduler's job by providing quantitative guidance in key areas. the amount of service provided, but increasing frequency (e.g., from 5 Service standards are typically set at a strategic planning or service planning level, but form to 6 trips per hour) is the same as a major input into the scheduling process. These standards may be formally adopted or may reducing the headway (from 12 to just be a working copy of a compilation of actual practices your system has developed through 10 minutes). Remember that reduc- the years. The discussion below covers some key items that are probably contained in your tions in headway actually increase system's service standards. the amount of service provided. Service Days What type of service is operated on each day of the week? Monday through Friday schedules are common, but that was not always the case. Many systems use a different Friday schedule span of service on some routes where traffic is particularly slow or where service operates later at night. Does the system operate on Saturday and Sunday? The service may or may not be the same on these The length of time, from the days. beginning of the first trip to the end of the last trip, during which service On larger systems, is there a holiday or otherwise reduced schedule operated on designated operates on the street. Span of holidays? Many systems operate Sunday schedules on "major" holidays. Major holidays are service can be expressed for a generally defined as New Years Day, Memorial Day, July , Labor Day, Thanksgiving Day, and route or for the system as a whole. Christmas Day. However, there are increasing demands to reduce service on so-called minor holidays, such as Martin Luther King, Jr.'s Birthday, the day after Thanksgiving, and Christmas Eve. Add to those regional holidays, such as Good Friday or Easter Monday, Columbus Day, Election Day, Veterans Day, and Presidents Day. How these are handled is designated in the Service Standards. Span of Service What are the operating hours of the route? Do the operating hours differ on weekdays from those designated for Saturdays and Sundays? What are the criteria for operating night service on a particular route? Do the operating hours apply to the whole length of the route, or all the branches? Policy headways A large share of service at many properties is determined by "policy headways." Policy head- ways set minimum service levels by policy rather than by capacity and demand; for example, all routes might operate every minutes in peak hours and every minutes in off-peak hours. For policy-based headways, there should be a standard defining when ridership levels would jus- tify added service. Policy headways can also be used to identify a minimum frequency of service. For example, a system could decide that each route would operate at least every minutes. 1 For a more complete overview of service standards, see TCRP Synthesis Report 10, Bus Route Evaluation Standards. 2-10

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Chapter 2. Inputs to the Scheduling Process loading standard Loading Standards The agency-established goal for The alternate approach to determining headways is demand-based, where the passenger passenger loads (not the maximum loads dictate the headways to be operated. Target loads are specified for different types of vehicle load, which is considerably routes during different times of day. For example, loading standards might call for average higher). The loading standard is loads of during peak periods and during the base period. Some loading standards may usually expressed as a percent- be expressed in other ways, such as percentage of seated capacity, number of standees (if any) age of seated capacity, as the allowed, or standees per available floor space. Schedulers and planners use detailed ridership maximum number of standees, or data to adjust headways so that the average peak load matches the standard (a simple division as the maximum load. The loading calculation in most cases). Depending on frequency of service, averages may be calculated for standard often varies over the day, each hour, each half-hour, or each -minute period. with peak-period loading standard higher than off-peak periods. Some Standards for Types of Equipment agencies also specify a time or Vehicle type or size can be dictated by many factors. These include passenger loads, accessibil- distance duration that certain loads ity, the road network, and capacity requirements. Scheduling may have the role of assigning are allowed (e.g., 150% for up to equipment to each route or to individual blocks in each route and therefore needs to be famil- 10 minutes). The loading standard iar with the characteristics of each type of equipment, primarily seating and standing capacity. is used to calculate demand-based headways during the various This task may be at the discretion of the scheduler or be mandated within the service specifica- periods of the service day. tion. The increasing popularity of low-floor buses, which have fewer seats than standard buses of the same length, has complicated the application of loading guidelines. Loading standards may be specifically called out for each type of bus, or may be set as a percentage of seated peak periods capacity. The hours during which ridership is highest, usually in the morning and Among the choices found on many systems, besides the standard 40 foot bus, are: afternoon commute times (e.g., 6 foot buses--ideal where loads are moderate and route to 9 AM and 3 to 7 PM). Sometimes clearances may be a problem. expressed as peak hour, the hour of highest ridership, it can also refer to foot buses--used on many shuttles serving residential to the period during which the most neighborhoods where boardings are light; perceived as more frequent service is operated, e.g., "neighborhood friendly". 45 foot "cruiser" bus peak 20 minutes. to foot "cutaways" (body on chassis, van or truck)--same applications as to foot buses, only with yet smaller vehicles. Some cutaways are now over feet long. base period foot articulated buses--deployed on heavier routes where the added carrying capacity can The hours between the AM and PM peak periods, during which rider- allow for wider headways and fewer operating resources to provide the same number of seats. ship is generally lower than in peak Not in common North American use, but similarly deployed, are double-deck buses. periods. Also known as "midday" or foot "cruiser" buses ("over the road" coaches)--an increasingly popular model for express and "off-peak period." park-and-ride service. Because of the high floor, number of steps and one-door configuration, they are not workable for local line service. 2-11

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Chapter 2. Inputs to the Scheduling Process Criteria for Adding or Eliminating Trips timed transfer The amount of service provided, both in terms of service span and frequency, is often dic- A transfer made easier and more tated by economics. However, a well designed system matches the level of service to service certain for passengers by the demand. Underserved routes may be overcrowded and may cause some riders to choose process of scheduling two or more other modes. Overserved routes are characterized by empty buses that could be better used routes to meet at a given location at somewhere else. Some routes are overserved over some portion of the route and underserved a specific time. A short layover may elsewhere. There is a temptation for public transit operators to be complacent in establishing be provided at the timed transfer standards for when service or parts of service should be added or eliminated based on produc- point to ensure that connections tivity. Ideally, for each service review, planners and schedulers have the ability to ask: "If I were can be made even if one vehicle is to start this route from scratch, applying all good planning principles, is this the level of service running slightly behind schedule. I would operate?" Timed transfers have become more important with the growth of Criteria need to be included in the service plan to set out how under-performing routes or hub-and-spoke network designs. segments will be eliminated. One particular system considers that any trip toward the end of the operating day regularly carrying less than five passengers is subject to being eliminated. Of transfer window course this number can vary according to the resources of the individual system. Also, circum- stances such as ridership on adjacent trips must also be considered. Often the last trip on a The layover time scheduled at timed transfer locations to ensure route is operated as a safety valve: it may have few regular riders, but it serves those who are that transfer connections can be delayed at work or elsewhere on any given day. made, and may also refer to the Other Considerations amount of time past its scheduled departure time that a vehicle can be Service standards might also dictate that headways be "clockface" wherever possible. Clock- held at a transfer location to wait for face headways are those that evenly divide into minutes and are capable of providing leav- a late arriving vehicle. ing times at the same time each hour. The pros and cons of this are explained later, but a quick summary would list ease of understanding for the customer as the major benefit and potential scheduling inefficiencies as the major disadvantage. service area Broadly, the area in which a transit Timed transfer requirements may also be explicitly stated by agency service standards, includ- agency provides service. This may ing locations and transfer window requirements. The scheduler is usually not concerned with also be defined as the area within a route spacing, but it is normally part of a service standards package. The amount of the service convenient walking distance (such area that is within the route catchment area (i.e., within a half-mile or quarter-mile walk, or as mile) of a route or a stop. For some other mandated criteria) may also be specified. GIS tools make the identification of the purposes of compliance with such areas relatively simple. Finally, much of the previous discussion on route design is usually the Americans with Disabilities Act, embodied in the service standards as well. service area is the area within mile of a fixed route service. Many transit systems consider unmet needs at regular intervals. These are often incorporated into early action plans that call for route expansion whenever operating budgets will allow. The scheduler, working with the service planner, needs to be aware of these and incorporate them into a service budget when planning an annual list of service changes. 2-12