The Last Mile Problem
While rapid transit solutions such as light rail, heavy rail, commuter rail, and bus rapid transit (BRT) are popular ways to increase a particular area's transit network coverage, the fact that they stop only every mile on average to maintain a high average speed means that geographically most of an urban area will be beyond an easy walking distance to a station. The fact that many residences and businesses lay beyond an easy walking distance to a station is known as the "last mile problem", and is a barrier to better utilization of a rapid transit network. This article examines the modes in which the last mile could conceivably be covered.
People are often surprised by how long rapid transit patrons are willing to walk to a station. While a generally accepted rule-of-thumb is that people will walk 1/4 of a mile to a local bus stop, people are usually willing to walk up to a mile to a rapid transit station. Note that we cannot just draw a circle with a mile radius around a station and conclude that all locations within the circle are within walking distance, as non-contiguous street networks and cul-de-sacs may mean that while people may be within one mile of a station as the crow flies they are more than one mile in walking distance away from the station.
How can we attract more pedestrian access to a station? By doing two things. First, we need to make sure that the access points are pedestrian friendly. Nobody wants to walk along a desolate arterial highway with a speed limit of 45 mph. Note that this means in some suburban situations segregated bicycle / pedestrian paths may have to be built. Second, we need to provide good wayfinding along the access points. Notable in this regard is central Washington, D.C., which features many road signs that advise people of the direction and distance of the nearest Metro station.
One aspect of pedestrian access that is often overlooked is the actual entrance to the station. In an attempt to value engineer to save money, many recent rapid transit projects in North America, particularly projects with underground stations, have stations with only one entrance. Even Toronto has a fair number of subway stations with one entrance; stations that, due to changes in the fire code, the TTC is now adding second entrances to. Having only one entrance means that over half the station passengers are likely to have to cross at least one and possibly two major streets to even enter the station. If the traffic light cycle is long then it could take five minutes just to get from one side of the intersection to the station at the opposite side. Certainly, having at least two entrances to any station is key to pedestrian access.
Using a bicycle is an excellent way to traverse the last mile from the station, as long as we understand that space constraints mean that in the long term bringing bikes on the trains themselves is not workable. Providing secure bike parking at the station is imperative, and providing easy bike rental for cyclists to use at their destination is also important. While bike parking has long been present at many rapid transit stations, bike rental has increased in recent years, with an announcement that Long Beach, CA will install bike rental stations in 2013 meaning that they will join cities such as Denver in providing easy bike rental near popular destinations including rail stations.
One way in which the last mile problem could be overcome is via local bus. In fact, the success of Toronto's subway system is due to the large number of connections the subway makes with local bus routes. Here are three conditions that local bus service needs to meet in order to be a viable solution to the last mile problem:
- Local buses serving the station need to be very frequent . For distances of less than five miles, transit will only be a viable option if the average waiting time for a bus (defined as half the headway) is very short, preferably ten minutes or less. As such, if local buses are to be used to carry rapid transit passengers the last mile then they should operate at least every twenty minutes.
- Connecting fares need to be very low . In Toronto, there are free transfers between the bus and the subway and most passengers use both. In the East San Francisco Bay region, transferring between local buses operated by AC Transit and trains operated by BART is expensive (although less costly than paying two separate fares). Not surprisingly, not many passengers use both.
- The connection between the bus and the train needs to very easy, both spatially and time-wise . A given is to avoid the situation Paul Mees discusses in Melbourne, in which buses left a train station two minutes before the train arrives. An attached off-street bus bay, like what is found at a transit center, is much better than having the buses stop on nearby streets.
The least desirable way to bridge the last mile is via automobile, either via "kiss and ride" drop-off locations or park and ride lots , as any area dedicated to car infrastructure leaves less for transit-oriented development and the construction of buildings that can act as trip generators. However, since in low density suburban areas the only realistic option may be to arrive at a station by car, park and ride lots will continue to be necessary.