The Tenderloin gap, part III

The last two parts (12) of this series focused on a north-south bus north of Market, but we never laid out the remainder of its journey further south. I think there are two major strategies for such a route—bring it into a major connection point or continue with the north-south gridline. What would these look like?

The most easily accessible major connection point is 3rd & 20th, with connections to the T, 22, and 48. With such a design, this route would effectively be participating in a secondary downtown radial pattern along with these routes. The T brings people in from the north and south, the 22 from the west and far northwest, and the 48 from the southwest. This bus would then bring people in from between the 22 and the T. This is even more prominent once the T is sent through the Central Subway.

3rd-20th-option

If we were to do this, land use at the nexus would need to support this anchoring of many frequent lines. Mission Bay is nearby, but the neighborhood is somewhat concerned about its expansion southward. The area is already zoned “urban mixed use” (UMU), which is a conversion from old industrial land use types to support more residential and commercial development. Think lofts built in old warehouses with ground-floor retail, and the like. While we like mixed use zoning, most of the parcels in this area have height limits of between 40 and 68 feet. This does not allow for very much density, and surely would not be able to support a second radial pattern. Perhaps the new Warriors stadium will provide the Planning Commission with a reason to raise the height limits in the area, but I wouldn’t hold my breath for that. Given that the T and 22 are such high-frequency and high-capacity lines and we plan to add another one, we’d probably want to raise height limits to at least 100 feet to take advantage of this. The AHBP might have been useful to provide taller buildings with more affordable housing in the area. While raising the height limits is a possibility, it is a remote one and we might be overserving this area quite a bit in the meantime.

If we were to continue the gridline to the south, we have a perfectly nice candidate already available—the 19-Polk! Given that the 19 is already bracketed by this bus and the 47/49, all of which are designed to be more frequent, we can scrap the 19 and use its southern leg for this bus instead, which leads to an increase in service for those riders. Since the 19 hits Market so close to where this bus would, it seems duplicative to try and fit an extra gridline in Potrero Hill, and we would probably have to introduce some confusing hopscotch to serve 6th St instead of 8th. This isn’t ideal because 6th St doesn’t cross over into Potrero like 7th and 8th do, but 8th St would be overserved if we ran both this bus and the 19 on it.

19-option

Muni Forward

SFMTA’s Muni Forward plan has a number of service changes planned which, if implemented, change the calculus for the two options outlined above. Under the proposed changes, there will be a lot of rerouting on the east side. The 9R-San Bruno Rapid has added a stop in front of San Francisco General Hospital, so the 33-Ashbury/18th will no longer turn down Potrero Ave and go down to the hospital. Instead, riders will be expected to transfer at 16th St and take the 9R one stop south. The 33 will instead continue eastward and take over this current leg of the route for the 22-Fillmore, which uses 17th and 18th Sts to eventually end up at 3rd & 20th. The 22 will then be rerouted to use the current route of the 55-16th St, and serve Mission Bay. The 19 is also rerouted to serve SFGH under this plan, with the 48-Quintara/24th taking over its route to Hunter’s Point. A new 58-24th St will take over the eastern part of the 48’s route and go to 3rd & 20th.

This would break up the 3rd & 20th radial hub, as the frequent 22 is replaced with the less frequent 33, and the fairly frequent 48 is replaced with the infrequent new 58. Add all this to the zoning changes needed to maximize the benefit from creating this radial hub, and it looks like this option will not work for us in the long term.

On the other hand, replacing the 19 south of Market is still a good idea: our frequent gridline has an anchor (SFGH) and the route is fairly straight. Thus, our bus can take over for the 19 no matter how many of the Muni Forward recommendations are implemented.

19-option-muni-forward

This new route also has the advantage of getting rid of that confusing bit it encounters as it crosses over Cesar Chavez, although the route is shorter, so some riders will have to take the post-Muni Forward 48 to 23rd & De Haro or Rhode Island to get on the new bus. In any case, this is still better than the other option should the Muni Forward recommendations come to pass. The pain of making this connection will be ameliorated by the increase in frequency.

Overall I like rejiggering the 19 instead of creating an entirely new line, since I think it works better with the land use. The other option looks nicer from a network perspective, but it is viable only if Muni does not follow through on some of its proposed changes, and if we get some help from the city to upzone the 3rd & 20th area. In effect, this ends up being a change of the 19 route, which shouldn’t be such a big deal—Muni Forward is already full of big route changes!

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The affordability balancing act

I apologize for the long break, but personal issues kept me from putting together posts or coherent thoughts of any reasonable length about transit recently. I decided to broach land use because we will vote tomorrow on a number of things that are going to affect it for the foreseeable future. This is always going to be a topic that consumes much of the political energy in San Francisco unless we have a miracle or a really deep recession.

A lot of my arguments for transit development rely on transit being the great equalizer. Everyone in the city should be able to get anywhere reliably, reasonably quickly, and inexpensively. This makes it especially tragic when transit access is a reason for gentrification or displacement. We have seen this in the past—a well-known recent example is the gentrification along the L train in Brooklyn. Many have argued that running BART through the Mission was one of the primary reasons for its gentrification, as well. Other efforts to expand and improve transit in SF, such as Geary BRT, have raised concerns because they might lead to gentrification in the western areas. But this seems to put us in a bind! If we don’t improve transit in low-income, minority and poorly-connected communities, we fail to enact the goal of transit, which is to serve those people as well as everyone else. If we do, then improved access is seen as a nice amenity for wealthy people who want to move in, and when that happens, we’re not serving low-income and minority communities anymore!

What this means is that transit activists must also be affordable housing activists, or transit activism won’t be worth nearly as much. Housing along high-capacity transit lines must be dense and include lots of affordable housing. A number of policy developments are taking shape in this area. Proposition C, which we will vote on tomorrow, seeks to push the inclusionary zoning (IZ) percentage up to 25%, grandfathering in current projects between 13% and 14.5% depending on when they were proposed, and allow the Board of Supervisors to change the IZ percentage without bringing it to ballot. We gain a lot of flexibility in housing policy by passing this, so if we find that 25% is too high, it can be dropped later after study determines what requirement produces the highest number of affordable units. The Affordable Housing Bonus Program is an attempt to give developers density bonuses in exchange for more affordable housing, and eligible areas are generally centered on frequent transit lines. It’s been reduced in scope in response to fears about displacement, but will still be useful. Aaron Peskin wants to expand Scott Wiener’s in-law unit legislation to the entire city, which could potentially unlock a new source of rent-controlled units, as well.

The other major policy statement has come from Gov. Jerry Brown. Mr. Brown wants to institute as-of-right development if projects meet existing zoning codes and have 20% of their units as affordable, or 5-10% if in a “transit priority area.” This is defined as the area within a half mile of major bus lines, trains, or ferries. I think as-of-right development is generally a good idea as it is what has allowed Seattle and Brooklyn to get a handle on their increasing rents, and the amount of process required to approve projects in SF is absolutely brutal. It seems like the lower IZ requirement near transit lines is meant to remove as many barriers as possible to transit-oriented development, which is well-intentioned. However, transit line catchment areas are exactly the places we should be building the most affordable housing, and I’m afraid that this might backfire as proposed. Without lots of upzoning or enormous density bonuses, both of which would likely face huge political battles, it would be difficult to ensure a meaningful number of transit-accessible affordable units are developed. And we might have an even bigger problem than that—depending on the definition of “major bus line,” most of San Francisco might fall into the transit priority zone, and the effective IZ requirement might drop precipitously across the whole city!

I imagine the insanity of the crisis and of local housing policy led Mr. Brown to propose something so sweeping. It’s good to see that people are not only thinking about simple, incremental changes that won’t ruffle any feathers. However, we need to make sure this doesn’t gut our ability to provide transit-accessible housing for everyone, or we’ve missed the point of having good transit to begin with.

The 19th Avenue Subway

The Market Street Subway is a bottleneck for the Muni Metro system, since each of its lines eventually merges into it. Early documents show plans for a four-track subway under Market; alas, we didn’t commit to that project and now we are stuck with a two-track subway. Combine this with the fact that the surface segments of each line force Muni to run one- and two-car trains where the stations could handle a lot more and it’s easy to see that we’re leaving tons of capacity on the table.

The Central Subway pulls half a line out of the Market Street Subway, which probably won’t improve the situation since we still have five lines in the subway at all times. In addition, the new Parkmerced developments are going to add thousands of daily riders to the M Ocean View line, which runs in mixed traffic on 19th Ave and is prone to some of the worst gaps and delays in the whole system. Muni decided to look at improving this line next. They did some studies, offered some suggestions that seemed lacking in the long term, and collected a bunch of community feedback.

Last month, something interesting happened: Muni greatly increased the scope of the project. The details can be found here, and I encourage you to go read those before I poison your thoughts with my editorializing.

If completed, Muni will have built its first fully grade-separated metro line, and it would improve the situation throughout the system. The M would be free of just about all gaps and delays, and it would use 4-car trains, greatly expanding the capacity of the Market Street Subway. West Portal will be able to handle many more trains and people. St. Francis Circle will be free of the crazy signaling, the intersection will be less complicated, and pedestrians will be able to make more use of the metro there. 19th Avenue will generally become more pedestrian-friendly and the line will better serve SFSU and Parkmerced. It’s a fantastic proposal, in my opinion. There are a few interesting details I’d like to point out as topics for further discussion or clarification.

J Ocean View

If this project completes as planned, the J will take over service in Ocean View. (We might need to rename some lines, but I digress.) The choice of the J to take over this part of the journey is interesting because it has a number of features limiting its capacity at the moment. One of the more frustrating issues with the J is the inability to run even 2-car trains along the line, because some of the stops would render the second car inaccessible. However, the plan explicitly talks about running 2-car J trains. Muni plans to remove one of the problem stops (Liberty St on the private right-of-way), but I’m not sure that this is the only one (21st St might be too short, and possibly Glen Park). This might boil down to adding a few square feet of concrete here and there, but it’s something that Muni hasn’t mentioned to date in its other Muni Forward plans.

This also means that the J will spend a much higher percentage of its time above ground and in mixed traffic, since it doesn’t look like there are plans to give it a red lane south of 16th St. This might not be an issue for Ocean View commuters trying to get downtown because I assume they will take the J outbound to SFSU Station and transfer over to the M, and it will probably be faster than what they have now. However, we have to be careful that we aren’t getting rid of delays on the M by simply passing them on to the J. The J will need extra reliability improvements so it can remain a useful part of the rapid network.

The Curious Case of St. Francis Circle

If you look at the rail map in the project details, you might notice the very strangely laid out subway station at St. Francis Circle.

st-francis-circle.png

At first, I took this to mean that the M trains coming through would always stop on the west side of the platform no matter which direction they are headed towards, and similarly for the K on the east side.

one-level-platform

This seemed like a strange interpretation because Muni is making this immense capital expenditure to get rid of delays and yet this seems like it might cause a lot of them. This limits the maximum frequency of trains through St. Francis Circle because they must maintain stopping distance while a train from the other direction is passing through. It also means that the M and K have the same maximum frequency in the station, which is not the most efficient way to do things—as extra capacity is needed, it would be more useful to swap out K trains for M trains and have some K trains terminate at St. Francis Circle. Riders could then transfer to the longer M trains for the rest of the journey. The K seems to have the same problem as the J in that it can’t support trains longer than 1 car, so running more frequent M trains through seems like a no-brainer.

I did some digging around in NYC Subway track maps to see if I could find an analog for this sort of station, and the closest thing I found was Queensboro Plaza:

queensboro-plaza

From the map alone it seems like Queensboro Plaza is structured the same way, with one track going through the station for the 7 and <7> and the other track for the N and Q. This doesn’t make sense when you’re running trains every two minutes in both directions. However, Queensboro Plaza is actually a two-level station, where the Manhattan-bound trains from each line stop on one level and the outbound trains stop on the other level. Each train has two tracks going through the station. It’s possible SFMTA is planning a similar structure for St. Francis Circle station!

two-level-platform

The structure is a bit harder to see here, but the western side of the station would have M trains, and the eastern side would have K trains. This would allow them to run trains in both directions without a bottleneck, and would provide a way for the M and K to cross over each other without sharing a single switch. There are some drawbacks—building this station and track layout is probably way more expensive than the one-level layout, and the inbound and outbound tracks for each individual line don’t actually meet anywhere, meaning we couldn’t terminate K trains at this station like we wanted to. In the one-level world, we can pull a train into the station and just back it out when it’s ready to turn around. With the two-level design, we’d probably have to run them to West Portal and turn them around there, which defeats the point. (This might still help since we can pull the K trains back before the L trains merge into the subway towards Forest Hill, but M trains might be stuck waiting for K trains to turn around at West Portal anyway.)

I guess the moral of the story here is that I’m not really sure what they want to do with this station, but the track layout they’ve picked makes me a little worried that we will again run into capacity issues sooner than we’d like.

The Daly City Extension

The plan leaves room for the extension of the subway to Daly City BART. BART and Muni already have plenty of connections at Balboa Park, but this one would be pretty useful because data from the Transit Effectiveness Project/Muni Forward on how people use the 28 and 28R (formerly 28L) show that Daly City BART is a good anchor for the line. Linking SFSU with Daly City by a direct subway connection is probably a really good idea since those are the busiest stops along the corridor.

This would also offer a kind of redundancy with BART in that there would be two discrete grade-separated lines from Daly City to Embarcadero, which would improve the resilience of the whole system in San Francisco. If BART is having problems in the city, the M might be a good substitute for people commuting up from the south. Of course, this might cast the lack of integrated fares into sharp relief, but that’s a much more complicated issue for another post.

Similarities to New Muni Metro

Back at the end of 2014, Nextransit published the first part of their New Muni Metro plan. The principles behind the Ocean View plan and the New Muni Metro plan are similar, though New Muni Metro didn’t expect to launch into multi-billion dollar capital projects for a long time. But they realized that we already have a fully-grade separated line if we end the Market Street Subway lines at West Portal. All of the other lines are streetcars only and people transfer to the Market Street Subway at West Portal (K, L, M), Church (N, J), or Embarcadero (T). The New Muni Metro plan also involves some line fusion, with the J taking over the surface portion of the K, and the L taking over the surface portion of the M. This means we could run all of the surface lines more often without worrying about whether we’re overloading the subway, and the subway will be able to run longer trains all of the time because there won’t be any short stations along its path. Higher surface line frequencies plus long, extremely frequent subway trains will mean way more capacity and generally shorter trips, even if you have to transfer.

I think the most interesting part about the similarity is that it means Muni could probably experiment with this same kind of service, should capacity become an issue. I alluded to this in terms of substituting K trains for M trains in the St. Francis Circle station design, but we could theoretically do this with any type of train. Forcing people to transfer probably wouldn’t make everyone happy, but the trains would be less crowded this way, so it might work out!

However the details fall out, this is incredibly exciting news. Transit agencies often avoid making grand plans like this because the funding for grand plans has dried up, but if we know that we’ll be getting something this useful out of it, the political situation might be workable after all. We shouldn’t be afraid to dream big—even if these projects seem expensive, they’re necessary, and nobody will look back on it in the future and think it was money poorly spent. Let’s see how Muni builds on this in the coming years!

Missing the point with a second tube

I figured I’d talk about BART some more because they’ve made it into the news recently. They’re currently fighting a lot of issues, and people are understandably mad, but I don’t think the absurd set of constraints the agency has to operate under gets enough airtime. It’s made even worse by the fact that people are demanding more and more of them as time goes on. Please be patient with them!

As I wrote about last time, talk of running BART around the clock seems to be reaching a fever pitch. One of the big topics here has been the second Transbay Tube, and it seems like people believe that this is necessary and sufficient for 24-hour BART. I think we badly need the second tube, but for completely different reasons. It also seems unlikely to me that this is all we’d have to do to get the trains running all night and we’ll be sorely disappointed if we use this as a justification.

The second tube is an absolutely necessary capacity upgrade, and we can see why from BART’s planning documents. Right now, the Transbay Tube carries 24 trains per hour during peak commute time. This means we can put about 23,000 people across the Bay in one direction in an hour. Unfortunately, it seems like we’re coming close to hitting this number already! This is a huge problem, because we won’t be laying another tube for decades. In the meantime, BART has some ideas to squeeze a little extra capacity out of the current tube. One is to make all Transbay trains 10 cars long. They currently don’t have enough train cars for this one, but the Fleet of the Future promises a massive expansion. They’ll also have to work out those crazy voltage spikes and power issues. When all is said and done, it’ll allow a modest capacity increase to 25,000 or 26,000 people per hour. Another relies on signal upgrades which should be included in the next BART bond. The benefits include an increase in frequency from 24 trains per hour to 30, pushing the capacity further up to around 32,000 people per hour. This is a big help, and is definitely the best short-term strategy, but the Bay Area is expanding so quickly that this will only help for so long.

Enter the second tube: BART projects we’ll be approaching the 32,000 passenger per hour limit in about 35 years, so we should probably begin planning this tube now. It will roughly double Transbay capacity and keep BART humming along even if it surpasses 1 million daily riders. It would also provide some badly-needed redundancy in case something goes wrong with the current tube or a station approaching it. Because of the improvements to capacity and robustness of the whole system, it’s definitely a worthy investment.

The redundancy aspect has people setting their sights on 24-hour BART. After all, if you can run the trains in one tube, you can close the other one for maintenance. If you switch off between the tubes on consecutive days, you should always be able to keep one of the tubes open, and we can run trains all night, every night!

There are a number of problems with this line of thought. For example, just because we have four tracks crossing the Bay doesn’t mean we have four tracks anywhere else in the system (save MacArthur, but that’s not really useful for this aspect). The new tube could play out in one of two ways. One is that it crosses the Bay, connecting up to the existing Market Street Subway in San Francisco. Another is that it creates a new BART line within SF city limits with some connection to the current subway. The most popular formulation of this concept has the connection at Montgomery and the new line running down Post or Geary.

Both of these plans have choke points that aren’t the tube itself—namely, they dump out into two-track subways, and if you close those down, you still won’t be able to run trains. While studying the New York City Subway, I realized that the decision to quadruple-track the trunk lines was one of the most brilliant decisions they made, as it allowed them to run trains along those lines no matter what happened. Unless we have quadruple-track subways, we’ll never reach that same level of availability.

Of course, New York City runs the trains all night on every line, not just the ones with four tracks. Plenty of lines run on two tracks when they leave Manhattan. Some lines, such as the L, have only two tracks the whole way through! I wasn’t sure what to make of this, so I asked my dad (an ex-MTA employee) how it was possible. He gave me two answers: Bus substitution, and the dreaded Planned Service Changes.

Anyone who has been in a subway station in New York has likely seen the enormous boards detailing all of the ways in which service will deviate from the official patterns in the near future. Trains might skip particular stops or there might be breaks in service along the line, requiring free bus bridges along the gap, or transferring to other trains. Trains from one line might use tracks from another line for some duration of their trip to allow maintenance on their own tracks. These service changes allow the trains to run all night, every night, but they have some cost. First, they rely on the network’s massive amounts of redundancy to continue functioning. Second, they make everything really complicated. The NYC Subway is already this huge, complex system with many lines and hundreds of miles of track, and remembering the standard service pattern is hard enough. It must be impossible to keep up if they have to change it all the time!

In either of the scenarios for the second tube, this same strategy of service changes to avoid maintenance areas isn’t going to cut it. The system simply doesn’t have enough redundancy to support the kind of service changes the MTA can pull off, and building that infrastructure now would require many billions of dollars. Let’s look at what we’d have to do even if we only built extra tracks between MacArthur and 24th St Mission, which is basically the smallest area for which it makes sense. We’d be paying for an extra 3 miles of two-track subway on the SF side and 2 miles of one-track subway on the Oakland side, and we’d have to rework the wacky subway-to-elevated transition as the C tracks move into the 980 median. This would add at least $4 billion to the total, and that’s in the absolute best case scenario. Reworking the transition and construction in the stations would probably cause service outages. It would also only grant us 24-hour service on a very limited section of BART. (This isn’t necessarily a bad thing, since we may only want to run trains all night in the areas dense enough with the kind of activity to support them. I assume demand for all-night BART to Pittsburg-Bay Point is pretty low. It is meant to highlight the immense expense of adding this infrastructure.)

What can we do? I know I was something of a killjoy last time when talking about the problems with running BART all night on weekends, but I think the conclusions there are valid here as well. If we can’t rely on service changes and we don’t have the infrastructure to do maintenance concurrently with service, then we’re going to have to turn to our old friend, bus substitution. As I stated before, even the NYC Subway resorts to this, so it shouldn’t feel like a cop-out. Bus substitution isn’t ideal because it drops capacity and doesn’t provide service as rapid as with trains. If we’re going to provide 24/7 service, we might need to do bus substitution at any hour, even during the commute rush. This could be really painful for a lot of people, especially while BART is already having capacity issues! We can do a little damage control by adding more switches in between stops so we’ll only have to substitute over one station, but this requires some extra infrastructure and is probably a ways off if so. We can see examples of this in the wild, though: Chicago’s L has switches between most stations on the two-track segments of its Red and Blue lines, and this is no doubt an integral component to their ability to run trains all night on those lines.

I think the new tube and 24-hour service are often tied together needlessly in discussions about the future of BART in a way that makes it hard to talk about what the former is actually necessary for, and what is actually necessary for the latter. My position on it is:

  1. If we want to be running trains all night, every night, then we do need to wait for the second tube, but that’s not even close to everything we need. Miles of extra subway and lots of new infrastructure will need to be built. Whether or not that’s a worthy investment is beyond the scope of this post, but we shouldn’t make the mistake of thinking we can build the extra tube and be done with it.
  2. If we’re comfortable with bus substitution, then we can mostly already get 24-hour service, if we are willing to tolerate substitution across arbitrary segments of lines and possibly at arbitrary times. This is, again, a value judgement, but given the outcry over the recent issues on the PBP line, I think this would be unpopular.

It’s great to see the Bay Area taking aim at New York here, but we do have to realize that their system is much better suited to 24-hour service than ours is, and we have a lot of work to do if that’s something we want as well. Either way, we are going to need the new tube. We simply shouldn’t delude ourselves into believing it will solve our 24-hour issue as well.

The all-night compromise

As the Bay Area grows, I’ve been hearing more and more talk about how we need all-night BART. Running trains all night, every night is a complicated problem that requires a lot of extra infrastructure to solve, so people are asking what it would take to enact a less ambitious proposal: running the trains 24 hours on weekends only. This seems like a reasonable middle ground, since there will still be time for overnight maintenance during the week, and people will be able to use BART to get in and out of the city on weekends.

BART makes a number of claims about why it doesn’t run all night:

  • Every hour of scheduled maintenance is necessary to keep the system in a good state of repair;
  • This work has to be done every night;
  • The longer maintenance windows on the weekends allow them to perform more complicated maintenance work that can’t be done during the week.

Even if we could postpone the night work on weekends, we would need to move those hours somewhere. Trains are still running along Pittsburg-Bay Point tracks until about 1:30 AM every day. During the week, they start again at about 4 AM. On Saturdays, they start at 6 AM, and on Sunday the line opens at 8 AM. This means our weekend maintenance window totals 11 hours each week. We can distribute these hours almost evenly throughout the week, though I’d suggest extending the Sunday night maintenance window with the leftover hour in order to try and make up for the backlog on the weekend. This means we’ve got 4.5 hours of maintenance from Monday night to Thursday night, and 5.5 hours on Sunday night.

It turns out we can’t really postpone BART’s opening, since the 4-5 AM hour is an unexpectedly big commute period. This means we’ll have to pull those maintenance hours from night service, and close BART at 11:30 PM five nights a week. It’s likely this service change will have a much bigger and more negative impact than the addition of late-night trains on weekends. It will almost certainly fail the Title VI analysis that requires BART to study the impact of service changes on minority and low-income riders. Past attempts by BART to extend weekend service were nixed for this very reason.

It’s also worth asking if this service change is going to help a lot of people. Boston’s MBTA recently voted to wind down its late-night subway hours, citing maintenance backlogs that are piling up, high expense, and low ridership, as expected. However, I think this article brings up one of the most overlooked points in this discussion:

“There aren’t that many jobs that are only two nights a week. We think this late-night service is not a broad solution to economic access because it’s not a seven-night-a-week service.”
Charles Planck, MBTA Assistant General Manager

If transit is supposed to be a great economic equalizer, then this plan for weekend-only 24-hour service isn’t what we want. People will be able to stay out later on weekends, but we pay for it by getting rid of late weekday service that people are probably using to get home from work, and we’ll likely need extra maintenance windows during normal service hours when more people need BART.

This isn’t to say late-night transit isn’t important—it is! The question I’d rather consider is whether it should be on rails, and I don’t think we can justify that. AC Transit’s 800 and 822 bus lines provide owl service along BART lines, but they come once an hour. I know late-night ridership is low, but if they’re that unreliable, people might act like they’re not even there!

Muni runs owl bus service on a number of lines. Some of them are not very frequent, but the most frequent show up about every 12 minutes. The N-Owl substitutes for an important rail line and shows up every 15 minutes. Philadelphia’s SEPTA runs owl buses on weekends along its subway lines, and these buses also come every 10-15 minutes. Why do the BART owl routes have such poor frequency in comparison?

The reason may be the length of the line. The 14-Mission has a route length of about eight miles. The N-Owl clocks in at around nine and a half. SEPTA’s Market-Frankford Line is just under 13 miles long. By comparison, the 800 route is almost 27 miles long! This means that service at a certain frequency on the 800 will require roughly twice as many buses (and drivers, and so on) as on the MFL, or three times that of the N-Owl. (This is a fuzzy approximation since about eight miles of the 800’s route are spent on freeways, but that still takes time.) As such, huge frequency increases on these routes might be expensive, but they are definitely much cheaper than the work required to bring all-night rail to BART. I would also argue that it’s wasteful to build that infrastructure if we can’t get decent ridership on buses with 20-minute headways or better. Not only that, but this liberates us from the weekend-only stipulation, and that probably serves everyone better.

The all-night BART discussion is often framed as a question of how to run trains all night. This tunnel vision has prevented us from looking at other modes of transportation that are better-suited to solving the problem in the near term. When you think about this problem, I urge you to instead look at it as a question of how to provide service to the areas covered by BART, regardless of the kind of vehicle that does it.

Completing the grid: The Tenderloin gap, part II

Last time, I talked about what I felt was a gap in Muni service. I’ll try and sketch out a line that would fill in this gap.

Since we are talking about a gap in service between Van Ness and Stockton, the best way to start would be to try and send a line right down the middle. As they are nine blocks apart, the middle lies between Leavenworth and Jones. We’re going to want to pick one of those streets to serve as the base for our line. A bus along this corridor will serve:

  • Civic Center Station
  • Boedekker Park on Eddy
  • Tenderloin Playground on Ellis
  • St. Francis Hospital on Bush
  • Grace Cathedral and Huntington Park on California, bordering which are many large hotels as well
  • The Pacific Ave neighborhood commercial district
  • Michelangelo Playground on Greenwich
  • The squiggly bit of Lombard for tourists, Yick Wo Elementary, and George Sterling Park if you’re willing to hike up to it
  • Fay Park and the San Francisco Art Institute on Chestnut
  • Russian Hill Park on Francisco
  • Conrad Square, Aquatic Park, and Fisherman’s Wharf

We should also allow easy transfers to east-west lines in the area, which would be the 1, 2, 3, 5, 10, 12, 30, 31, 38, 45, and 47. Of these, the 1, 5, 30, 38, and 47 are part of the frequent grid, so connections with these are especially important.

Designing the line

Our first instinct might be to use both streets in a one-way split, but one-way splits have a number of drawbacks. They make lines more confusing, as I talked about last time. They also reduce the area that is within walking distance of both directions of the line—a good explanation of why (and why we want to avoid this) can be found here, with diagrams. Our hope is to minimize use of one-way splits where possible.

Leavenworth and Jones are zoned similarly in Nob Hill and Russian Hill, so that’s not going to inform our decision. Since the 19 exists on the Van Ness side, and northbound buses south of Geary are further away than Stockton, let’s try Jones first.

North of California, Jones is a two-way street, so we’ll use it for both directions of this new bus line. Most buses in this area go up to North Point, so that’s our main destination, and then riders will easily be able to transfer to the 47 to head east and west. The 30, E and F are also very close to North Point & Jones. We’re also going to need to turn the bus around, and we can do so with a small one way loop like on the 19, extending from North Point to Beach.

jones-simple

If we look closely at this map, though, we’ve done something impossible—Columbus Ave has a median in some areas, and one such place is right where Jones would cross it. We can’t go through here. Our proposal might include breaking up this median and only allowing Muni vehicles to cross. This would require a lot of extra signaling and would complicate traffic patterns on Columbus that the median was presumably intended to simplify, so I’m going to consider this unsatisfactory. We can look at some changes in routing that avoid this problem section of Columbus.

side-by-side-1.png

Both strategies take us to North Point. Each one has its own complication: the first suggestion makes the line a bit wiggly, and the one-way loop terminating the second option is needlessly large. I’ll choose the first option for now.

Below California, Jones is a one-way street running south. We can make the bus use Leavenworth for the northbound leg, turn right on California, left on Jones, and continue up with the path as mentioned before. We’re trying to avoid one-way splits as much as possible, but here it seems justified. These streets are one-way, and since they are less than 500 feet apart, the one-way split doesn’t affect the service area too much.

jones-full-route

For now we are running the bus down to McAllister, which is right before it hits Market. Let’s try out our route. We send an imaginary bus up from Market on Leavenworth, where it turns right on California, and left up Jones. We get to Green St and start going down a huge hill… in fact, this hill is so steep that our bus goes into free-fall!

The steepest grade any Muni vehicle negotiates is 22.8%, which is along the 24-Divisadero as it travels on Noe St between 26th St and Cesar Chavez. The 24 uses trolleybuses specifically because this hill was too steep for motorcoaches to climb at the time. Modern motorcoaches can do the job, as you might find when a Castro street fair closes off a whole bunch of streets and they can’t use the overhead wires anymore. The buses and trolleybuses might be able to transit steeper grades, but we’ll consider it an upper bound for now, since we don’t actually know if anything steeper will work. Jones between Green and Union is a 26.2% grade—even if we could get down this hill, it’s immediately followed by a 29% grade between Union and Filbert, and going back up later is definitely out of the question. (You can find official grade maps here.)

We can try and route around this hill as well, but we risk making the route too complicated. I’d rather move the base of the route from Jones to Leavenworth. The steepest part of the line north of California is a comfortable 22.2% grade between Union and Filbert, and the end of our route already moves over to Leavenworth anyway. This generally serves the same area while keeping the line as simple as possible. We’ll still try to use Jones south of California because Leavenworth is one-way northbound during that segment.

leavenworth-initial-route

Let’s try the imaginary bus again. We send it up Leavenworth, where it makes it all the way to North Point, loops around and starts back towards Market. We come down to California, make a left and then a right around the odd guard rail… and promptly bottom out on the crest! Jones has a 24.7% grade between California and Pine, so putting a bus on it is not a safe bet. This means we can’t use Jones here, either! We have to explore some backup plans.

  1. Use Hyde to get to Bush or Post, take it to Jones, and use that to go towards Market.
  2. Use Mason to get to Pine or Sutter and take it to Jones.
  3. Use Hyde the whole way down to Market.
  4. Turn one lane of Leavenworth into a contraflow bus lane.

southbound-options-map

Option #1 recreates some of the leapfrog one-way splits we saw in the confusing 27 route, which we’re trying to avoid in creating this line, so that’s not a good idea. Option #2 entails a 3 block wide one-way split, which is one of the problems with the 8 and 30 that we are trying to work around by having a mid-Tenderloin line. Option #3 is workable, but risks nudging the service area a little too close to the Van Ness bus brigade. It does not require drastic infrastructural changes, so we can keep it on the table for now.

Option #4 is very interesting. Contraflow bus lanes are often used to turn one-way streets into two-way streets for transit purposes. Other traffic will only be able to go northbound on Leavenworth, but buses will have exclusive access to a southbound lane. I don’t believe they are currently used in San Francisco. This requires a little bit of infrastructure work such as painting the lane red and adding proper signage, as well as adding traffic lights at each intersection. An intermediate proposal might use a contraflow lane for a short time until the bus can get over to Jones, probably via Bush or Post. However, Leavenworth is a large street south of Geary. If we are going to use the contraflow lane north of it to avoid the California crest on Jones, we might as well take a lane out of the wide part to improve simplicity and speed.

Here are our possible alignments:

southern-area-final-options

Through any of these options, we can connect Fisherman’s Wharf with Market at Civic Center Station.

Stop selection

Local buses in San Francisco stop every two to three blocks, so we can follow this model when picking stops. Ideally, we want to line up the stops with the east-west lines, so we can maximize its usefulness as a grid line.

full-map-final

If both the northbound and southbound trips use Leavenworth, then all of the stops north of Market are marked here. If we use Hyde for the southbound leg, we can use the same set of cross streets, but we’ll want an extra stop on Grove before continuing southeast on 8th St. The McAllister and Grove stops are very close to Civic Center Station. I also added an optional stop on Bush to serve the hospital more directly, since hospitals are destinations that you might want to add stops next to even if there are other stops nearby. For precedent on this in the current Muni network, check out the 9R-San Bruno Rapid, which stops in front of SF General Hospital on Potrero Ave even though it stops again one block away on 24th St.

Unfortunately, we are not done—this route only takes us to Market, and grid lines are more useful when you don’t have to think about where they start and stop. In the next installment, I’ll draw the rest of the line south of Market, and we can decide what a good anchor for the other side of this frequent line would be.

Completing the grid: The Tenderloin gap, part I

If you look at a transit map of San Francisco, you might find some surprising holes in the coverage. Perhaps we can learn something about network planning by trying to fill them in.

One of the more confusing examples of this is the lack of north-south lines running through the Tenderloin, Nob Hill, and Russian Hill. The Tenderloin is one of the densest areas in the city and has a lot of below-market-rate housing, so adding service would increase mobility for a lot of people. Nob Hill and Russian Hill are also very dense and poorly connected by transit, which means we have a big opportunity here.

Fisherman’s Wharf employers have trouble filling positions because the area is out of the way, and having more service there could bring in more employees and tourists. Because it is such a big destination and it just north of Russian Hill, it can serve as an anchor for one end of the line. Another important point on this line would be a connection to Muni Metro and BART.

Lastly, if we want a frequent grid that functions well, we have to make sure the grid lines are not spaced too far apart, or our reliably-covered areas will have huge gaps.

Let’s look at the current map of north-south lines to see what we’re up against.

ns-lines-map-full

You might look at this and say, “Coverage seems fine!” That’s true, but for such an important area, there is startlingly little frequent transit, and the lines aren’t very simple. If we evaluate each of these lines, the picture comes out much bleaker.

First, let’s look at the 19-Polk. North of the Tenderloin, this bus is basically a less reliable Van Ness bus. It runs less frequently, there is no owl coverage, and any speed problems plaguing Van Ness buses will be put to rest by Van Ness BRT in a few years anyway. I’d wager that any time the 19 saves by going faster is cancelled out by the extra wait. The portion in the Tenderloin has one-way splits, and they cross over each other a few times, making the route harder to remember. Perhaps it is useful for connecting some areas to Civic Center Station, but it seems to me more like the old 26-Valencia, which was an infrequent bus next to a bunch of really important and frequent lines running on Mission. The 26-Valencia was discontinued in 2009 for this reason.

Let’s update the map.

ns-lines-map-no-19

Next, let’s talk about the 27-Bryant. This bus has a number of problems. First and foremost, it does serve the Tenderloin, but its route is plagued with so many leapfrogging one-way splits that it’s impossible to remember where the stops are! It seems like planners were trying to follow an imaginary extension of 5th St northwest on the other side of Market. Dragging this diagonal line across a normal grid is a recipe for disaster and the incredibly confusing route proves this.

This line also has a poorly-anchored terminus at Van Ness between Washington and Jackson. I don’t know of anything there that will attract riders other that the connection to the 47 and 49 lines and possibly the Academy of Art. It seems like the decision to terminate the line there was an attempt to keep Tenderloin bus riders out of Russian Hill, especially when you compare the route of the 27 to its neighboring cable car routes (which we’ll get to in a minute).

In addition to problems with the alignment, the bus is not that frequent. I don’t think this is a suitable north-south line in the frequent grid. One more time:

ns-lines-map-frequent-only

The cable cars are interesting, because they are actually quite frequent. They are anchored at both ends by Union Square in the south and Fisherman’s Wharf/Aquatic Park and North Beach in the north. However, they are specifically routed around the Tenderloin, likely to avoid serving its residents. This shows they are aimed at wealthy Russian Hill/Nob Hill residents and tourists, and aren’t a useful part of the grid, either.

It is important to note that the Tenderloin used to have more cable car routes, and the cable cars used to be a more equitable mode of transit. This fell apart in the mid-1950s when the city government was trying to dismantle the Tenderloin. One of their weapons was removal of cable cars that went through the neighborhood, which city officials claimed were “dragging down” the city. The city said the cable cars were slowing down automobile traffic in Union Square, which it was desperately trying to expand into the Tenderloin. They also promised to replace the affected lines with buses as part of a “modernization” effort.[1]

It’s clear that this was a move to contain the Tenderloin and its people rather than improve the transit network. It wrecked transit access in the Tenderloin and we can still see the effects today. Here’s what we’re left with.

ns-lines-map-frequent-no-cable-cars

This is the north-south component of our frequent grid in this area. It looks a little bare, doesn’t it? This, too, has problems for anyone living in the center. The one-way splits on the 8-Bayshore and 30-Stockton are extremely wide (4 blocks apart!) and so the area which you can really call “covered” by those buses is greatly diminished. The 8-Bayshore is split all the way up to Columbus, making it especially useless in the middle area.

The distance between the Van Ness buses and the Stockton buses is also very far:

ns-lines-map-frequent-distances

Keep in mind that all of the northbound Stockton buses use Kearny when they are south of Sutter. That means your nearest frequent bus might be half a mile away, and south of O’Farrell, it might be even worse! In the average case, it’s still 8/10 of a mile between routes. Noted transit planner Jarrett Walker often talks about frequent grids in network design and says that parallel lines should be generally 1/2 mile apart and at most 3/4 mile apart, so a gap this large means we are underserving the middle area.

I think we’ve laid out the case for having another frequent north-south line here. Next time I’ll discuss what we should think about when we design it.


  1. The Tenderloin: Sex, Crime, and Resistance in the Heart of San Francisco by Randy Shaw, pp. 96-98