DC Metro’s expectation in cutting Blue Line service was that many Blue Line riders would switch to the Yellow Line and transfer, thus reducing the overcrowding. While it may be a questionable planning strategy to make individual’s preferred path so awful that they choose an alternate route, it is true that Blue Line riders have an alternate route into the core. In their initial planning, WMATA expected between one-fifth and one-third of Blue line riders to transfer instead of dealing with the insufferably long wait times.
Turns out, transferring is more painful than WMATA expected. Just 14% switched – hence, overcrowding on the blue line.
So why was Metro so wrong? It turns out that people really hate to transfer. Some papers looking at the psychic cost of a transfer in subway systems suggest that adding a transfer is equivalent to adding almost 10 minutes to a trip (one study I found says subway transfers have a psychic cost of 8 minutes, another says 9.5 minutes).
So when Metro is giving riders a choice between taking a Yellow/Orange transfer or waiting 10 minutes for the next Blue Line train, the psychic transfer-cost alone eats away all of the time savings. When you add to that fact that taking the immediate yellow line train may not even get you there sooner, it’s no surprise that Metro was off with their projections.
This also means that Metro is substantially underestimating the true costs that they are imposing on the Blue Line riders by cutting Blue Line service.