The Case For Quarter Mile Bus Stop Spacing

You know the feeling. You hop on local route XYZ, hoping for a somewhat speedy journey to work, home, or play. Maybe today the bus will hit the jackpot. Then the familiar sound comes once every block, a soothing voice speaks the words “Stop Requested.” Sometimes it happens the instant the bus is pulling away from its previous stop. Your inner Hulk flares up. But then! A glimmer of hope – a new block without anyone grasping for the yellow cord! But, somehow the Universe knows. Someone boards at the next stop anyway.

It doesn’t matter if it’s rush hour on the 4 or catching a southbound 6 at 9 PM after a Thursday night Gopher football game (ok, both personal experiences). To make matters worse, you become increasingly aware of how many cars without yielding to your bus trying to re-enter the stream. You curse those exiting when you miss the next green by mere seconds (and sometimes see the same person walk by you out the window!). The whole ordeal certainly contributes to local routes that average well below 10 mph operating speeds. What’s to be done?

Background

Let’s get some basics of transit service, passenger behavior, and other items out on the table for those curious.

• A “walk-shed” is the geographic area that transit planners assume a bus/rail/gondola/zeppelin stop or station will draw passengers from. This is typically assumed to be 1/4 mile for bus stops (more on that later)
• A transit service plan requires a tricky balance between operational efficiency and access to adjacent land uses. Spread the stops out too wide and you’re serving fewer people and destinations within a given walk shed (but speeding up service). Place them too closely together and you duplicate coverage areas and increase trip times, but serve more people and businesses.

In Minneapolis and St Paul, most of our streets (outside the CBDs, some of SE Minneapolis, and perhaps a few other odd neighborhoods) were largely built out as streetcars serviced new neighborhoods (with the main goal of getting those people to each downtown). To minimize number of intersections crossed per mile traveled, the blocks were built as rectangles, twice as long as they are wide. Minneapolis is largely structured north-south and St Paul east-west (following the streetcar routes), but the blocks are the same: 660′ long (1/8 mile) by 330′ wide (1/16th mile). This isn’t abnormal – many neighborhoods of midwestern cities that boomed during the streetcar era share similar block proportions and dimensions.

Actual walk-sheds depend on the connections that surround a bus stop. Oftentimes the term “radius” is used, but the reality isn’t always a circle. For the purposes of this post, I’ll assume a grid used in Minneapolis, St Paul, and many inner-ring suburbs. It may be less applicable where local routes serve areas without a robust pedestrian network

People are willing to walk different distances in different places to a bus. We’re also willing to walk different (often longer) distances to rail (or any transit with high perceived level of service). A bus walk shed is typically viewed as 1/4 mile, but cities across North America vary:

Many factors play into this: culture, local climate, daily weather, how pleasant the walk is, how safe the walk is, and how desirable the transit service is you’re walking to. Many European transit systems already recommend urban, local routes use 400-600m spacing (link, page 5) – roughly 1/4 to 1/3 of a mile.

Similarly, people assign different time costs to different portions of their journey – walking to or from a bus stop and waiting carries 2-3 times the personal cost of in-vehicle travel time. Put simply, people would rather sit on a slower bus but walk/wait less (especially if it’s cold or rainy).

The Case for Quarter Mile Spacing

No transit planner worth their chops would be surprised by the information above. In fact, Metro Transit is doing a great job focusing on the arterial BRT program, which implements wider stop spacing (among other huge improvements) on many key urban transit corridors. The average spacing ranges from 0.3 to sometimes above a half a mile, which is too far to justify dropping the existing local routes from the corridors.

But what about those remaining local lines? What about the other (many) routes in our transit system? What if we could speed up their service without spending much from transit’s limited capital and operating budget? What if doing so could allow a bus to run more frequently without adding any operating costs (or new buses)?

Most bus routes today (outside of the CBDs with shorter block faces) have stops every long block (or every second short block) – or every 1/8th mile (660′).  I propose we change this to a quarter mile (1,320′) standard. The former is certainly on the low end of most urban municipality standards, while the quarter mile is definitely on the high end (excluding those crazy Europeans, of course):

The Positives

While no bus in our system stops every block, every hour of the day (indeed, many low frequency, low rider routes go many blocks without making a stop), we can almost guarantee that consolidating stops will lead to faster run times for the popular ones. Research supports this – with studies showing an increase in bus trip speeds between 5.7 and 10 percent.  The same studies show mixed reviews on impact to bus schedule reliability, with one showing no impact and another having a positive impact. This could mean 3-5 minutes saved off a typical transit trip (depending on length, etc).

In addition to improved service by trip time, Metro Transit could use the operational efficiency to improve route frequency. Rough hypothetical example: 10 buses (and drivers, and diesel fuel, etc) are required to run a route every 15 minutes, allowing them to run faster gives options. A 10% improvement in speed could allow Metro Transit to use just 9 buses for the same level of service, OR keep 10 buses operating at better headways – 5 buses an hour is better than 4, right? Thus, transit riders could see improved trip times AND reduced average wait times at stops without Metro Transit spending a dollar more.

Any operational gains that aren’t pumped back into the system through service improvements could instead go into stop amenities.  Metro Transit maintains over 10,000 stops, yet as the Star Tribune excellently points out, they struggle to provide basic shelter at hundreds of shelters, many of them in urban locations. Heat, shelters, and better signage all cost money, and this provides a source.

The Drawbacks

Obviously, there’s a downside. Consolidating stops means serving fewer people (and businesses) within the same walk shed:

With stops every other block (green dots) and an assumed willing walk distance of 1/4 mile, we certainly leave some areas out that used to be “in” (blue). Furthermore, we add walk distance to a fairly significant chunk of land that was closer to an “every block” stop:

About 14% of the land area that used to be served now has a 2.5 to 5 minute longer walk, and a whopping 36% of the transit’s captive area must walk between 0 and 1/8 mile further (the red line being the most affected) – about 0 to 2.5 minutes.

However, we know that land use patterns have consolidated along the transit’s route over time. More businesses are at the legacy streetcar stops than several blocks away. Apartments, duplexes, row homes, etc are more common along the arterials than several blocks away. A “no GIS database” rough estimate would say 80-90% of riders would see marginal changes in walk distance.

Additionally (and despite the walk/wait time cost discussed earlier), the studies linked above show that ridership held steady after consolidation (Portland) and actually grew (Seattle) despite other system routes seeing ridership decline. I would wager a bet that faster and potentially more reliable service could 1) convince those who must walk further to continue to ride, 2) draw new riders from within the walk shed, and 3) make new (car-lite/free) development near stations more attractive.

Conclusion

Stop consolidation could be an extremely inexpensive (they’d still have to go remove those signs, print new schedules, market the changes, etc) means of improving service on every urban bus route. When done in combination with other (slightly more expensive) improvements such as all-door boarding (recently highlighted by Bill), better stop placement, signal preemption (or at least holding a green), we could see much needed improvements to bus speeds for very little cash.

Yes, there are other factors to consider, most important among them being those who an extra 3 minutes walking might truly be a challenge (disabled, elderly, etc). As boomers age this certainly becomes more of a challenge. We should evaluate the capability of Dial-a-Ride services to adequately serve these individuals, perhaps on a pilot route (and I define “adequately” as “equal to or better than current trip times”).

But if you believe the system-wide benefits are too great to ignore, share this with any high-ranking Metro Transit employee or Met Council councilmember you happen to rub elbows with at fancy dinner parties (I jest). OR, you can get serious and make comments on Metro Transit’s Transportation Policy Plan – there’s a hearing on September 17th. Additionally, Metro Transit’s Service Improvement Plan is in development and should be ready for comments in November. Share your thoughts, and use this post as a reference!