BART, one of the SF Bay Area's transit systems, is on strike today, and people are scrambling for alternatives. The various new car-based transportation companies like Uber, Lyft and Sidecar are all trying to bump their service to help with the demand, but in the future I think there will be a much bigger opportunity for these companies.

The average car has 1.47 people in it, and the number is less on urban commutes. Since most cars hold 4-5 people, the packed roads have a huge amount of excess capacity in empty seats. While Lyft and Sidecar call themselves ridesharing companies, they are really clever hacks at providing taxi service. Lyft's original product, Zimride, is more ridesharing but aimed at the long-distance market. Many companies have tried to coordinate true ridesharing for commuters and people in a city, but with only limited success.

A transit strike offers an interesting opportunity. Without commenting on the merits of the sides in the strike, the reality is that we can do much better with the empty seat resource than we do, and a transit strike can prompt that.

Of course, the strike is already naturally increasing carpooling, and casual carpooling (also known as slugging) also gets a large boost. In the Bay Area, things are complicated because BART is the main alternative to the Bay Bridge, and that bridge is going to get very heavily loaded. Ferry service is increasing but it's still a 25 minute trip every 45 minutes from the various Ferry docks. The bridge and highways are increasing incentives for HOV-3+ carpools.

Casual carpooling tends to only get you to a rough area near your destination. In this case that may be OK, as other transit is still running, only BART is out. At the semi-official casual carpool stations, there are signed waiting places that get long lines for all the general destinations. You take what you can get, and it's also efficient in moving cars in and out.

Computer assisted carpooling could schedule people together who are both starting and ending their trip fairly close together, for maximum convenience and efficiency. If the trip starts at people's houses, or some common point, you don't have the casual carpool concentration issue. If you start from stops of the transit lines which are running, you still have a problem.

Because of the load on the bridge, the ferry seems attractive, though there you have a chokepoint, particularly in picking up people from the boat. To do that, you would need a parking lot with numbered spaces. People allocated to a car because of a common destination would be given a spot number, and walk to the car there as they get off the ferry. A simple curb (which suffices for casual carpools) would not be enough.

Companies like Lyft and Sidecar make use of people who want to become part-time taxi drivers. While they pretend (for legal reasons) that they are people who were "already going that way" who take along others for a donation, that fiction could become reality in a transit strike. Most carpoolers would probably take along extras for no money, or gas money, especially when they gain a special carpool lane or toll saving as they do on the Bay Bridge. There would also be value in Jitney service, where a "professional" driver (who is just driving for the money, officially or not) takes 3-4 passengers along the common route, and they all pay a reasonable share.

Within a city, that share could be competitive, even with the subsidized cost of transit, which tends to be close to $2/ride. Taxi fares are $2.50/mile plus a flag drop, which means a trip of 3-4 miles could be competitive if split among 4 people, and not that bad (considering the higher level of service) even on trips that are twice as long. (The Bay Bridge is 10 miles long so taxi fares will have a hard time competing with even the higher BART fare.)

Jitney service (shared door to door or on-demand fixed route) is quite popular outside the USA, and indeed there are many cities with active private transit systems and jitney systems. But most Americans are not interest in the inconvenience of going slightly out of their way to deal with the needs of other passengers, and so attempts at such rideshare here don't rule the world. It's probably too late for this strike, but the next transit strike might end up demonstrating there are other systems aside from transit that are efficient and cost-effective.

The interface would not be too different from existing systems, except people would specify how much inconvenience they would tolerate from having others in the vehicle and going out of their way, in exchange for savings.

When it comes to robocars, this might happen as well, and it could even happen with vans to provide a very effective shared system that still offers door-to-door. Robocars also offer the potential for mixed-mode vanpool trips. In such a trip, a single person robocar takes you to a parking lot, where 12 other people all arrive within the same minute and you call get into a van. The van does the bulk of the trip, and stops near your set of destinations in a parking lot where a set of small single-person robocars sit waiting to take people the last mile. This highly efficient mode should be able to beat any existing transit because of its flexibility and door-to-door service. The vans offer the ability to be luxury vans, with business class seats with privacy screens, so that upscale transit is also possible.