Back in the 1960’s Muni was part of the SF Public Utilities Commission. In the late 1960’s the oncoming BART subway give Muni an opportunity to modernize its streetcar system. So the PUC sent one of its engineers to Europe to get a better look at some of Europe’s successful subway operations. He returned with a recommendation that there be a single 10-car train extending from State College to the Embarcadero, fed at the West Portal by short K-L trains and at the Duboce Portal by short J-N trains. That recommendation was rejected by the PUC brass on grounds that San Francisco’s streetcar users, used to getting one-seat rides to downtown San Francisco, “didn’t want to transfer and in fact wouldn’t transfer”.

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So the Louis T. Klauder Company…. a pre-eminent rail system design firm….was brought in to design a light rail vehicle (LRV) subway surface system suitable for San Francisco’s unique arrangement; namely five surface streetcar lines feeding into a single subway.

A compromise was eventually reached. It was decided to operate one and two car trains on the Avenues and couple the shorter trains into longer trains at the portals so as not to overload the subway. With this innovative solution it became possible to avoid sending excessively long trains through outlying neighborhoods while holding the number of subway trains per hour to a reasonable number. And that’s the way the Muni Metro system operated between 1980 and the mid-1990’s.

If properly managed such a system could accommodate 24 trains of average length 3.5 cars in the subway an hour, thereby permit 16,800 riders an hour or more to use the subway during the commute peaks. However the Muni experienced problems in with the coupling, allegedly because of defects in Boeing Vertol’s LRV design, and by the mid-1990’s, the PUC’s General Manager declared that he’d “had enough”. Unfortunately, instead of looking seriously into what could be done to solve the coupling problem it was decided to abandon coupling altogether, meaning that henceforth the trains operating in the subway would be only one and two cars long. Despite warnings that such a change would reduce the Muni Metro’s peak-period carrying-capacity by almost 60%, Muni proceeded with the plan to send as many of the short trains coming off the avenues into the subway as possible.

To cope with the excessive peak period crowding caused by this action, it was necessary to compensate for the decreased train length by sending far more one and on and two-car “trains” an hour through the subway than it could handle . The result was predictably horrendous daily backups, which knocked most trains off schedule and consequently degraded the entire Muni Metro system. By the time COVID caused a temporary shut down the system in early 2020, the newly formed SFMTA was struggling to accommodate an impossible 43 separate Muni trains an hour in the subway. For this to work every train would have had to remain exactly on schedule for every minute of its trip; needless to say, an impossible objective. The short-train experiment was an unmitigated disaster.

After again refusing to consider or even discuss seriously how coupling could be successfully reinstated, the SFMTA’s plan of August 2020  would have forced up to 40% of the Muni Metro riders bound for eastern San Francisco to get off their surface trains at the portals and transfer to trains traveling in the subway. What was wisely rejected by the PUC in the late 1960’s was and still is being aggressively pursued by the SFMTA brass.

When the effects of the pandemic eased, thereby allowing the temporary Muni Metro shutdown to end, a reduced ridership gave Muni the opportunity to reinstate regular service.  Yet, to avoid again overloading the subway, Muni, as of now has fully reinstated only four of the its pre-COVID Muni Metro lines.