In between the airport connectors and mixed-traffic streetcars are some public transit proposals that would be potentially high-performing. This is a list of potential lines in the US that don’t get nearly the exposure that they deserve.

The basic rule of this post is that if it’s being built, or is on an official urban wishlist pending finding the budget for it, then it’s not underrated. Some of the most important transit projects in North America are in this category: Second Avenue Subway’s current and future phases, the Regional Connector, the UBC SkyTrain extension. What I’m interested in is lines that are only vaguely on any official wishlist, if at all, but could still get very high ridership compared to their length. It is possible that these underrated lines would turn out to be worse-performing if a study were undertaken and the costs turned out to be very high, but in no case was there an honest study. Sometimes there has been no recent study; other times there is one but it sandbags the project.

Finally, I am not including commuter rail projects on this list. Under current regulations and operating practices, nearly all North American commuter rail projects are wastes of money. Conversely, nearly all projects that assume modernization of practices are underrated. This swing, based almost entirely on organizational question, is why I’m excluding these projects from this list. The subway and light rail projects below are less sensitive to organizational questions.

Utica Avenue Subway

Location: New York

Concept: an extension of the 4 from Crown Heights along Utica Avenue to Kings Plaza, about 7 km. If Second Avenue Subway’s Phases 3 and 4 are built, then a branch can be built from Second Avenue to Williamsburg and thence under Bushwick, Malcolm X, and Utica, taking over the entirety of the line, with the 4 cut back to its current terminus; this is an additional 9 km to Second and Houston.

Why it’s underrated: the second busiest bus route in New York, the B46, follows Utica: see here for New York bus route rankings. The busiest follows First and Second, which are getting a subway. Two additional routes in the top ten, the B44 and the B41, follow Nostrand and Flatbush respectively, fairly close to Utica. The B46 has 48,000 weekday riders and the B41 and B44 have another 70,000 between them. Since subways are much faster than city buses, the expected ridership is much higher than 120,000, measured in multiples rather than in a percentage increase. In addition, the 2, 3, 4, and 5 are all busier coming to the Manhattan core from Uptown than from Brooklyn, so adding to their ridership from the Brooklyn end balances the loads better, and avoids the required increase in operating costs for the new riders.

What is being done right now: nothing.

Geary Subway

Location: San Francisco

Concept: a full subway from Market Street to the Outer Richmond District, about 9 km. This can connect to the BART subway, the Muni Metro tunnel, or a second Transbay Tube if one is built.

Why it’s underrated: the 38-Geary is the busiest bus route in San Francisco, with 57,000 weekday riders between the local, the limited, and the express buses: see here for San Francisco bus ridership. Parallel corridors are also busy: the 1-California has 29,000, the 31-Balboa has 10,000, and the 5-Fulton has 17,000. Some of the census tracts along the middle of the route, in Little Osaka Japantown, rank together with Los Angeles’s Koreatown as the densest in the US outside New York. BART’s current limiting factor is not the Transbay Tube, but the grades farther south in San Francisco, which lengthen the braking distance and make it impossible to run a full 30 trains per hour through the core segments; a Geary branch leaving south of Montgomery Street would reduce service to points farther south, but improve capacity for riders heading from Oakland to the San Francisco CBD.

What is being done right now: there were never subway plans, but there were light rail plans, which due to local merchants’ opposition to loss of space for cars were downgraded to a rapid bus. The city’s FAQ on the subject even has the cheek to portray the Boston Silver Line and the Los Angeles Orange Line as successes.

Downtown Relief Line

Location: Toronto

Concept: there are several different alignments, but all feature an east-west line somewhere between Queen Street and Union Station, with one or two bends to the north to intersect the Bloor-Danforth Line. The latter two alignments (using option 4B for the second one) feature about 12 km of tunnel; I do not know how much the first one has.

Why it’s underrated: only one subway line serves Downtown Toronto, the Yonge-University-Spadina Line. Bloor-Danforth is too far from the CBD, and requires a transfer. The transfer points are very crowded: as far as I can tell from this list, the central one, Bloor-Yonge, has 200,000 weekday boardings, apparently including transfers. Without figures that include transfers in other cities I can’t make comparisons, but I doubt any two-line, four-track station in New York has this many riders. Union Station is quite crowded as well, and DRL proposals include transfers to outlying commuter rail stations. Ridership on parallel streetcars is very high: there are 53,000 on King Street, 44,000 on Queen, and, if a more northern alignment for the DRL is chosen, 32,000 on Dundas.

What is being done right now: more studies; construction will almost certainly begin any decade now. Neither David Miller’s Transit City light rail proposal nor Rob Ford’s replacement of Transit City with subways included the DRL.

125th Street Subway

Location: New York

Concept: either Phase 5 or Phase 2.5 of Second Avenue Subway, going west along 125th to Broadway, with a station at each intersection with an existing north-south subway.

Why it’s underrated: east-west transportation in Manhattan is slow, even by the standards of Manhattan buses. The 125th Street buses in my experience are slower than walking; despite this, the various routes have about 90,000 weekday boardings between them, of which about 30,000 come from 125th Street itself. Second Avenue Subway Phase 1 is going to substantially improve east-west transportation, by serving Times Square and offering a two-seat ride from the Upper East Side to the Upper West Side and Central and West Harlem; however, passengers from East Harlem will still have to take a major detour to avoid the crosstown buses. While SAS offers a relief to the 4/5 and 6 lines, the 2/3 and A/D express lines are overcrowded as well, and a connection at 125th Street would divert some East Side-bound commuters.

What is being done right now: nothing, although (some) railfans who work at the MTA privately want to see such a line built.

Silver Line Light Rail

Location: Boston

Concept: replacement of the Silver Line buses along Washington Street with light rail, feeding into an existing Green Line portal, about 4 km of light rail.

Why it’s underrated: the Silver Line buses are the busiest in Boston, with 15,000 weekday riders on the buses to Dudley Square: see PDF-pp. 47-48 of the MBTA Blue Book. The ridership doesn’t justify a subway, but does justify dedicated lanes and rail. The Green Line tunnel has some spare capacity, has a portal pointing in the correct direction, and could take an additional train every 6 or 7 minutes, which would give riders in Roxbury faster trips through Downtown Boston.

What is being done right now: nothing – a study sandbagged the rail bias factor and assumed only 130 new transit riders on a Silver Line light rail service, making the project appear cost-ineffective.

Triboro RX

Location: New York

Concept: a circumferential subway line, with about 1 km of new tunnel and 35 km of route on preexisting rights-of-way, abandoned or lightly used by freight trains today.

Why it’s underrated: the biggest cost driver, right-of-way formation, is already present. The right-of-way in question has a few daily freight trains, but the most critical link, the Hell Gate Bridge, is four-tracked, and freight trains can be kicked out from their segment of the bridge and moved to the Amtrak tracks. The work done by Michael Frumin and Jeff Zupan in the late 1990s estimated about 150,000 commute trips per weekday (76,000 commuters each making a roundtrip per day), which is low for a greenfield line of this length but reasonable for a line on existing rights-of-way.

What is being done right now: nothing, although ever since Lee Sander mentioned the line in 2008, politicians have paid lip service to the concept, without committing funding.

Boston Circumferential Line

Location: Boston

Concept: a circumferential subway, from Harvard Square to Dudley Square or the JFK-UMass subway stop, roughly following the 66 bus route where it runs and intersecting the busiest stops of the Green Line branches and some commuter rail stops. This is about 12 km.

Why it’s underrated: although the busiest Boston bus is the Silver Line to Dudley Square, the next few are circumferential, particularly the 1 and 66, and secondarily the 23 and 28; together this is about 50,000 riders. Boston’s street network is hostile to surface transit except on a few major streets such as Washington, which is why there is no hope of making such a line light rail, which would fit the projected ridership better. A route that parallels the 66, at least until it hits the E branch of the Green Line, would intersect the B, C, and D branches at their busiest respective surface stops, and improve connectivity to Cambridge, which is increasingly a major business district of the Boston region in its own right.

What is being done right now: BRT, on convoluted alignments that don’t exactly follow either the 66 or the 1 where they are parallel but instead make detours.

Nostrand Avenue Subway

Location: New York

Concept: an extension of the 2/5 from Flatbush to the southern end of Nostrand Avenue, about 5 km.

Why it’s underrated: all the reasons that make Utica so strong apply to Nostrand secondarily; the present bus ridership may be high enough to support two subway lines rather than one. The present terminus was built as a temporary one, which is why it has side platforms rather than an island platform.

What is being done right now: nothing.