San Francisco’s Muni Metro system was originally designed to operate one and two-car trains on city streets, where longer trains weren’t needed, and then to couple the short trains into three and four car trains suitable for subway travel. This arrangement was used from the time the Muni Metro system opened in 1980 until the mid-1990’s when the General Manager of the SFPUC (which then operated Muni) made his fateful decision to discontinue the coupling. This meant that in order to keep up with demand it would be necessary to operate the one and two car trains in the subway. As demand increased it was necessary to continually increase the number of these short trains to the point of their completely overloading the subway and causing the entire Muni Metro system to be snarled up, virtually on a daily basis.
In early 2020 the drop in transit use caused by COVID temporarily put the problem on ice.
But now demand is starting to rise again, meaning that if nothing changes the SFMTA will likely soon be faced with the same problem. Absent coupling, the dreary choice will be to 1.) again overload the subway with short trains, or 2.) send unnecessarily long trains out into the avenues to disrupt cross traffic, or 3.) force a substantial number of Muni Metro riders to transfer between trains to get to the eastern parts of the city. None of the three is acceptable.
For this reason it is necessary to take another look at coupling, which the SFMTA has so far refused to do or even talk about, despite the fact that passenger trains are successfully coupled and uncoupled during revenue service in many parts of the world.
It is emphasized that in the case of the Muni Metro system, six branch lines all feed into one Market Street subway which make San Francisco’s system much more dependent on coupling than most other systems. Here are several ways of proceeding without gumming up the subway, disrupting the avenues or degrading the service for a sizable percentage of Muni Metro riders: