Service Design
Bus Service Networks and their Advantages/Disadvantages
- The most important factor in the quality and adequacy of service provided by a fixed-route bus system is the design of the network of routes
- Radial patterns can continue to effectively serve work trips to downtown areas as long as there is a reasonable concentration of employment
- If downtown commercial activities are relocated to the suburbs, this type of transit network may not have convenient access to newer locations
- Grid-type bus route networks feature relatively straight, parallel routes spaced at regular intervals and crossed by a second group of routes with similar characteristics
- An advantage of a grid-type system for an area that has widely scattered activity centers is that riders can get to and from almost anywhere with one transfer, without having to travel back through a central point such as the CBD
- Another advantage is the relative simplicity of the system
- The disadvantage is that in order to get from any place, a transfer is often necessary
- For a grid system to work well:
- Frequent service should be furnished on almost every line with headways being every 15 or 20 minutes or less
- If population density or ridership is low and will not support frequent headways, it is doubtful that a grid system will be very successful
- One way to obtain certain characteristics of a grid system and still maintain the benefits of a radial system is to use a modified grid system that crisscrosses the lines and provides additional points where lines converge
- The lines also provide grid-type transfer opportunities to intermediate locations which wouldn’t be possible under a pure grid system
Geographic Characteristics
- There are many land use factors that impact travel mode:
- Regional accessibility
- Density
- Mixture of land use
- Roadway design and connectivity
- Parking supply and management
- Population density and employment density together have a significant impact on mode choice and ridership
- Ridership demand is more dependent on demographic and socio-economic trends
- Land use/urban design examples:
- Sidewalks
- Population density
- Employment density
- Parking fees/parking availability
- Availability of parking
- Average commute time
- Housing density
- Retail, commercial, service, industrial, employment density
- Average parcel size
- Pedestrian environment factors
New Service and Service Enhancements
- Service changes address issues of:
- Route efficiency
- Cost-effectiveness
- Operational feasibility
- Availability of resources
- Service standards are applied to:
- Improve route productivity while keeping customer impacts to a minimum
- Assure service is provided in a fair, consistent, and equitable manner, with consideration for transit-dependent areas/regions
- Provide a baseline for sservice planning of bus route alignments, and scheduling frequencies for all transit modes
- Transit agencies should continuously evaluate the performance of its services, analyze data and develop recommendations for service changes as justified using service delivery standards
Development of Sketch Plans
- Sketch planning is used to produce general order-of-magnitude estimates of transit service and resource and cost impacts
- Developing sketch service plans to meet passenger and operational needs provides planners with an idea of the feasibility of each specific plan
Resource and Cost Estimation Process
- Cost determination is the process of identifying the total cost of providing the service
- Expenses should be allocated to:
- Miles (maintenance wages and fringe, parts, fuel, tires, and accidents)
- Hours (driver wages and fringe)
- Vehicles (management, advertising, legal fees, office supplies, training, overhead items, and utilities)
- A variety of approaches are used for cost models in transit planning:
- Simple extreme: Average system cost per unit of service
- Complex extreme: Reschedule the whole system to look at the effects of a change and run-cutting
- Intermediate: Cost models with a limited number of variables per hour, mile, and vehicle
Demand and Revenue Estimation
- Transit use is generally measured through unlinked passenger trips and passenger miles
- One of the most common issues for transit planners is how to estimate demand changes tht might occur if various service characteristics or fares are changed
- When introducing rail extensions or BRT, such changes induce much larger changes in traveler behavior such as:
- Changes in overall tripmaking
- Origins
- Destinations
- Modes of travel
- Routes
- Time of travel
- Many forecasts have been overly optimistic in their forecasts of transit ridership, while underestimating actual costs
Fine Tuning of Plans through Approval Process
Improving Transit through Efficient Planning
Making the Tough Decisions of Service Reduction
- There are some occasions when transit systems are forced to:
- Cut service
- Raise fares
- Have layoffs
- The goal of service reduction is to reduce costs with a minimum impact on passengers, especially those with limited or no alternative transportation
Improving Capacity by Increasing Travel Speed
- To obtain higher capacity, one may increase the frequency of buses or increase the passenger-carrying capacity of each bus
- Improved speeds can result in a better headway at no additional cost if the average speed of a route can be increase by reducing bus stops or providing priority to transit
Planning and Scheduling Measures to Improve Reliability
- Reliability is one of the service characteristics most important to transit customers, while service quality and customer satisfaction have been linked to higher levels of retention, and possibly even ridership gain
- In theory, improving transit service reliability has been linked to increases in transit demand for particular routes and should also increase service productivity, given accurate schedules
- Methods for improving transit service reliability include:
- Implementing changes in driver behavior (through training)
- Better matches of schedules to actual service
- Control actions
- Transit signal priority (TSP)
- Modifying route design (length, bus stop consolidation, and relocation)
Coordination with other Transportation Organizations
- Transit service will need to become less stratified and more regional, with seamless connections for passengers traveling between one provider and the next
- Transportation programs share resources, facilities, and information, as well as coordinate trip reservations, scheduling, dispatching, and passenger trips
- A successful coordination effort will lead to changes in institutional structures (e.g., numbers of providers, funding sources used, etc.); services (e.g., service types, hours per day, areas covered, etc.); and performance (e.g., efficiency, effectiveness, and costeffectiveness)
- Some potential benefits of transit coordination efforts include:
- Benefits to transit riders/travelers
- More travel choices for commuters
- Increase mobility and independence for people who don’t drive
- Improve availability and convenience of medical trips
- Benefits to transit providers:
- Improved cost-effectiveness and use of resources
- Expansion of service area and client
- Improved visibility of transit service in the community
- Ability to leverage new funding sources
- Benefits to transportation system:
- Reduction in vehicle emissions
- Additional travel capacity without building more lane miles
- Benefits to employers and the workforce:
- Opportunity to attract new workers
- Reduced need for parking facilities
- Potential element of corporate pollution-reduction programs