more on microtransit/DRT

[mindstalk]

I spent much of today reading some of the Transit Capacity and Quality of Service Manual, which is a long and 176 MB PDF that I expect to never read all of, since much of it is technical and numeric stuff of interest only if you're actually running a transit agency. But chapter 2 is largely talking about different transit concepts and types, which I did find interesting. And in particular it went into the history and various types of Demand Responsive Transit (DRT), and their productivity or ridership (passengers per vehicle-hour, or 'revenue hour').

general public DRT: the classic door to door "dial a ride" service. What's called microtransit now if it comes with a mobile app. Urban ridership of 2.9-4.7, higher than I expected. Rural 2.9 (multi-county) to 4.4 (municipal).

limited eligibility DRT: like paratransit, though also related services with restricted destinations (not allowed for ADA paratransit.) Ridership 1.5-4.35, with the high end in systems that restrict destinations e.g. to senior centers and human service agencies. ADA paratransit is even lower: "the largest city transit agencies achieve productivity levels from 1.3 to 2.3 passenger trips per revenue hour, with most below 2. Transit agencies in large cities have productivities ranging from 1.8 to 2.7 and, in small cities, from 1.8 to 3.8 passenger trips per revenue hour... In major metropolitan regions, for example, ADA paratransit productivity may be as low as 1 passenger trip per hour." I'm guessing that smaller cities mean shorter trips and thus better trip grouping and/or vehicle turnaround, plus maybe less congestion.

Connector/Feeder service: The description isn't detailed, but sounds like an agency SuperShuttle, service meant to connect to a transit station, though apparently it can do some local transport within a zone, too. Ridership 2-8. This section also mentions a rare win over fixed bus service, in Denver:

"The agency's first DRT connector service replaced a poor- performing fixed-route bus service in 1999 that carried 1.6 passengers per hour at a $78.46 subsidy per passenger trip. One year after implementation, the Call 'n Ride replacement service served 4.3 passengers per hour for a subsidy of $9.84 per passenger trip."

Dallas had a hybrid On-Call service, acting as a feeder during peak hours, and more flexible off-peak.

Zone Routes and Point Deviation: the descriptions don't give me a clear idea of what either one is, or how they differ. But riderships are '3' (one data point) and '2.5-4'. I guess I should give the descriptions. Zone: "Zone routes combine DRT service within defined zones along a corridor with scheduled departure and arrival times at one or more end points." Point: "Point deviation service, also called checkpoint dial-a-ride, operates within a defined area or zone, providing demand responsive service as well as scheduled service to a limited number of designated stops, without any regular route between the stops."

Route deviation, flexible-route, flex-route: A fixed-route bus, that also makes detours on request within a limited zone around the route, like 0.5 miles for example. Can also have a time budget for detours, like "20 minutes an hour" or "2.5 minutes an hour". Ridership 2.5-20 (!) with the high end not allowing much deviation.

I'd actually thought of this on my own, when trying to imagine a better model for paratransit. Say a grid of what I dubbed 'flexbus' routes, running at decent frequency. Seemed like it would likely be more responsive and reliable than the existing model, at the cost of needing to transfer for many trips. And the manual has a paragraph about how flex-route interacts with ADA requirements.

Flexible route segment: "Flexible route segment service is predominately fixed-route service but converts to DRT for a limited and defined portion of the route." Like doing DRT within one community, before driving to another community. Rare. Ridership 2.5-3.

Request stop: "Request stop service is predominately traditional fixed-route/fixed-schedule service but which also provides service to a limited number of defined stops close by the route at the request of a passenger. This is different from flag stop service in that the request stops are not directly on the route."

Sounds like a bus, except that it might detour to a specific mall or nursing home etc. if requested. No mention of how you get picked up; call in, I guess? Ridership from just one data point, at 6.

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Discussion: So, for all the variety, note that they rarely break 4 passengers per vehicle-hour, and never 5, with a few exceptions: many-to-one connections to a transit point (feeder/connector), or restricted deviations from what is otherwise a bus (flex-route and request-stop). (And paratransit suffers relative to general DRT because it has a smaller customer base, and those customers need longer wait times and more time to get on or off the vehicle, possibly including assistance going from the vehicle to their destination.) Nonetheless, apparently sometimes DRT does make sense, like that 1.6 passenger/hour bus line in Denver.

That said, a lot of this stuff doesn't seem very stable. The manual mentioned Dallas DART having both the On-Call service mentioned above, and flex-routes aka FLEX. I looked it up, and in the past few years DART replaced both with GoLink, which is basically a heavily zoned rideshare system (including falling back to UberPool): 32 zones, and you can't go between zones, so it's meant for very local service including connecting you to a transit stop. I couldn't find ridership for this. The manual says that the old flex-routes averaged 8 passengers/hour, but apparently even that wasn't enough to keep them from switching models. (Also says that if a route hit 10 passengers/hour for 3 quarters, DART would look into conversion to fixed route.)