In order to open the Silver Line last year, Metro has had to run more train cars longer, and the extra mileage put onto them has meant their breakdowns may affect your service more often.That's probably true, but we believe the fact that three of the four lines with the greatest deterioration (SL, OR, BL) run through Rosslyn station on the two-track tunnel downtown is a, if not "the", key driver in this phenomenon. As Repetsky notes, extremely cold weather last winter was also a contributor to performance deterioration--just exactly the time when potential users are seeking good rail transit service.
These graphics capture the major deterioration in performance, especially "did not operate" (DNO):
It is important to highlight that the deterioration in DNO performance and volatility in on-time performance shown above began in late 2013 or early 2014, many months before the Silver Line began operations and before extra rail cars were needed. That speaks to extremely poor maintenance, not too much demand for cars.
In fact, if it were not for the Silver Line, total usage of the system would have declined over the last year. And even among the limited number of SL stations open in Reston and Tysons, only Reston has exceeded usage forecasts for the first year. We do not expect SL usage to increase until service improves and the new Phase 2 stations to Loudoun are added.
One cannot also help but notice that, in 2011, WMATA lowered the target on-time performance from 95% to 90% (black line, top graph). Lowering the bar is not the answer to providing reliable Metrorail service. It is merely a justification for poorer service.
Most importantly, it shows a continuing systemic deterioration in Metrorail performance for more than 18 months. And we still don't know the true causes and potential solutions for this increasingly dangerous situation.