What are the principles of an integrated public transport system?

An integrated public transport system is a public transport system that has ideally two or more forms of public transport (buses (local, feeder and transit), light rail/trams, commuter rail, transit rail or suburban rail) working together to adequately provide for the transport requirements of the town's/city's/region's populace.

"We cannot reduce congestion by building more roads since immediately we get more traffic to fill them up to the same speed as before. The only way to reduce congestion is to introduce better public transport facilities which reduce the number of people who travel by car on the roads."
Professor Martin Mogridge, University College London

Principle One: An integrated public transport system needs to have different (i.e. more than one) kinds of transport available. This ensures both adequate coverage and frequency of service.

Principle Two: An integrated public transport system has its transport services working together, by having compatible routes and timetables.

Principle 3: An integrated public transport system provides the city/ area in question with both enough transport coverage and enough service, by having transport coverage for ~90% of the area and frequent service (for an elaboration of what constitutes frequent, see Frequency of Services)

Principle Four: An integrated public transport system must provide access for the user, as well as provide options for their travelling needs.

There are several factors that can affect an integrated public system. These can include its connectedness, cost, availability/frequency of services, type of services used, access, traveling time, and level of both government and public support.

What types of services are normally used?

Bus services.

There are many different types of bus services in public transport, and there is some overlap in terms of function and nomenclature. However, the most commonly used terms in bus transport are:
  • Local bus service: Bus service providing both access and transport to a local area. Route completion time is usually about 40 minutes, and bus stops are located every 200 to 400m (1/8th to 1/4 mile). Average passenger journey is 3km (2 miles).
  • Feeder bus service: Bus service that provides transport to a transport hub/ activity centre from a local area.
  • Transit/ Commuter bus service: This bus service is different from the others mentioned. The bus route has three stages; catchment, transit and destination. The catchment stage is the first part of the journey. Most of the passengers get on, and very few get off. The transit stage is solely travelling. No passengers picked up or dropped off. This stage usually involves the body of the traveling, usually along a major road or highway/freeway. The destination stage is mostly letting passengers off, essentially the opposite of the catchment stage.

Light Rail/ Tram services.

These services are usually less numerous than the bus services (in terms of numbers of routes), but provide much more frequent service (i.e., every 5 to 10 minutes). They are generally slow, with average route times sometimes longer than an hour. In most cities, they do not extend outside the city centre and its surrounds, but in a few cities, they are quite destination oriented, sometimes extending into the far suburbs. Mostly, they share the roads with vehicles, and do not have right of way. This means that vehicles can get in the tram's way, and delay its journey. In traffic jams, this is even worse. For some reason, light rail usually runs down the middle of streets. This means that, not only do vehicles have to share the lanes, passengers have to cross to the middle of the road to board the tram. This is dangerous. Far better to have the tracks riding on the edges of the road, next to the footpath. That way, it can double as a bus lane and not hold up traffic for passengers to board. The downside to this: cost and loss of parking spaces. Such a shame!

Heavy Rail/ Trains.

The most understood form of public transport. Well, not really, but if you live in a city, you are probably more likely to think of trains than anything else at the thought of 'public transport'. They can be above ground, below ground, or elevated. They generally form the bare bones of any integrated public transport system. They are rigid and inflexible systems, however these same attributes mean they are predictable and dependable, in theory. In theory, trains should be the predominant forces driving the integrated system. This theory can quickly fall flat on its face when services are inadequate.

Note: this is merely an anecdote about the infuriating city I live in. It shall remain nameless. I live in a growth corridor suburb. This suburb has doubled in size in the last ten years. I used to be able to see across the farmland to the hills in the north. Now all I see are the grotesque houses all the new neighbours are building. Anyway, the buses are plentiful (one every 40mins at the end of the block, or walk 1km to catch another that come 20mins later), but the trains are not. The closest station is the second last on the line (from the city, or the second station when going to the city). The trains run every 20mins. In peak times, they have 6 cars and an express every hour. Regardless of which train you catch between 6am and 9am, by the time you reach the third station there is no room. Zip. Nada. Zilch. Sweet F all. You get the idea. 30 years ago, when the population of the surrounding area was about a quarter of the size, the timetable was precisely, exactly the same. Nothing has changed. The city itself has large transport woes. In terms of rail projects, the government is approximately 75 years behind the schedule. In 1916, the need for a CBD rail bypass was noted and plans were drawn up for feasibility. The project was done, it was begun in earnest in 1977, and completed in 1985. This meant that many more services could be run without having to turn the trains around. Nice in theory, but achieved little observable improvement.

Rail transport is divided into a few different types.

  • Rapid transit: This is generally defined as a service that has schedules at 40km/h (25mi/h) or more, and is designed for journeys longer than 6 to 8km (3.75 to 5 miles). Commuter rail is a form of this, but is more destination-oriented
  • Local-feeder services: These services are designed for the shorter journeys, and generally travel at 20 - 25km/h. This is also referred to as suburban rail

Government Support

The planning and implementation of an integrated public transport system is intrinsically tied in with urban/town planning. Since the planning of infrastructure is predominantly under the jurisdiction of government bodies, the extent to which public transport is incorporated and integrated into planning submissions is entirely reliant on those government bodies. If they are supportive of public transport, then the extent of incorporation is likely to be significant, and public transport may even be given some concessions of priority (like priority bus lanes or bus areas) over private traffic. If the government body is unsupportive of public transport, and instead favours private transport, it will plan accordingly. Simple as that.

Public Support and use can influence transport policy... well, maybe

Public support and patronage can also influence public transport services. If there is visibly enough support for service extensions, or there is enough demand for increased services, the government body may implement these demanded services. but this is not an easy achievement, as government bodies are somewhat notorious for being deaf, blind, and a little thick. You can form a community action group, and you could get a large petition going round, and you could have meetings with the planning bodies. But this is no guarantee of success. "Public transport costs money", "nobody uses it", "why can't people just drive?", these are just a few excuses the planning body may voice in response. But this is to cover a minor little detail they will not tell you. They do not support public transport, and they do not wish to spend money on it since they believe that it is a waste of money.

Public transport is planned using complex equations and data analysis tools

Surprisingly, this is true. Planning departments, in association with local government bodies, conduct demographic surveys in relation to public transport use. From this they determine whether more services are required, or if a different transport route would be better. For each public transport type (I'll list them again. They are:- buses {local, feeder and transit}, light rail/trams, commuter rail, transit rail or suburban rail), there is an access threshold. I don't actually know if this is the term used, but it encapsulates the idea well. The access threshold is the distance public transport users are willing to travel to use a particular type of public transport. You could also call it a public transport catchment area. This distance depends on many variables, like the geography of the area, both physical (face it, would you rather walk up a hill from your home to catch a bus, or walk further down the hill to the train station?) and human (would you catch a bus if the nearest stop was within the threshold distance, but you had to walk nearly twice that distance because of the street plan?), and the frequency and availability of the service have a significant impact as well.

So, what are these access threshold distances?

I know that the access threshold for most bus services is 400m, or a quarter of a mile if you use Imperial measurements. I can hypothesise the threshold distances for some of the other transport types, but please accept these as guesses. Light rail or trams would probably be about the same as buses, so I would guess they have a direct threshold/catchment area of about 400m. For these services, walking distance is the benchmark, both when you catch the service, and near your destination, if the service doesn't go to the door. However, light rail/ trams are a little different, as they may often have an indirect catchment area. These services often intersect with other transport types. Users may often get on at these intersections, having used another service to get there. Usually, this previous service was a bus (most likely to have been a local bus or a feeder service, as transit bus services are more destination-oriented and more likely to be the recipient service of such intersections, rather than the donor service.

So, what is important for an integrated public transport system?

Access. Simple as that. Almost deceptively simple. That would be because it is deceptively simple. Access to what? Places that planning bodies would call activity centres. We're talking shops, schools, community centres. Basically, anywhere people need to go. On the flip side of this is people's homes. The underlying principle of an integrated public transport system is to provide the option of getting person A to wherever they need to go, in a reasonable amount of time without much difficulty.

What does it need?

An integrated public transport system requires two things; micro-level planning and macro-level integration. Micro-level planning takes place in the neighbourhood. This is where the activity centres are identified and the local transport routes are planned to supply access to the activity centres. This neighbourhood is then supplied with access to a greater area, also through public transport routes. If the neighbourhood has destination-oriented transport like trains, light rail/trams or transit buses, then this step is bypassed, as these transport types require the inclusion of both intersections and feeder services. These intersections are also classified as activity centres, as they attract people.

Activity centres fit into one of three categories; principal activity centres (these are significant locations like a central business district or large town centre), major activity centres (these are smaller versions of principal centres, and include paces like significant town centres, suburban centres, etc), and neighbourhood activity centres (these are activity centres that are significant on a local scale, and include places important to a neighbourhood, like local shops, recreational and community facilities).

These activity centres are separated into two broad categories for public transport purposes. To meet the access needs of a population, the categories of activity centres are treated in different ways. Principal and major centres are linked using what is referred to as a ‘principal public transport network’. The outlined purpose of this principal network is to connect the significant centres with public transport. Some neighbourhood activity centres are also likely to be accessible with these services. The neighbourhood activity centres are accessed using a local network of services. These local networks are typically connected to at least one, and possibly more significant activity centres, as well as a number of neighbourhood centres. For an integrated public transport system to work optimally there must be a sufficient amount of intersection between the local and principal networks to provide both 'access' and 'options' to the user, so they can plan their journey.

The macro-level integration is largely made up of lots of intersections and large activity centres. Large shopping centres (they are also called malls, an ugly and unpronounceable word) are designated as either significant or principal activity centres. This is unsurprising, given the numbers of visitors every day. They often have bus terminals for many, many of the local bus routes. Not only does this mean access, this also makes an intersection for those routes. This is good all round. The shopping centre has public transpor acces to the local area, the local areas have access to the shops, and there is a feeder/intersection effect to boot. A feeder service is one that collects users and brings them to an intersection. An example is a local bus service that runs through the area between two neighbouring train stations. it terminates at the train stations, providing both the local area and the stations with access.