In the final three months of 2009, buses broke down more often than in previous quarters. Flickr photo: WarzauWynn

With grim news on most Muni-related fronts, including massive service cuts coming in two weeks, Muni managers also have to contend with a new quarterly performance report [PDF] that shows on-time performance suffering and more missed runs than usual in the last three months of 2009.

Service got worse in several key areas, including customer-observed schedule adherence, headway adherence, scheduled service hours delivered, vehicle availability, and the percentage of buses and trains exceeding maximum load during peak periods. Some categories, like headway adherence, were worse than the annual average for any of the previous five years.

As abysmal as those trends are, they’re not exactly up-to-date: they reflect the two months before Muni implemented service changes in December, as well as the first several weeks of those service changes. Unlike the 10 percent service cut due to arrive on May 8, the December service changes were virtually neutral in terms of the total amount of service hours Muni is scheduled to deliver.

The numbers suggest that one of the most serious problems is a lack of proper vehicle maintenance. While last year’s report was marked by a dramatic worsening in the mean distance between failure (i.e. breakdowns) for light rail vehicles, the end-of-2009 quarterly report suggests that trolley coaches (electric buses) and motor coaches (diesel buses) were suffering the worst maintenance issues. Overall, the mean distance between failure for buses dropped for a second straight quarter.

One of the few bright spots in the report is that operator absenteeism improved, dropping from 14.8 percent in July through September to 12.9 percent in October through December. But that positive trend may already have reversed, judging from daily service reports in early 2010.

Overall, the report paints a picture of the dangers of not properly funding vehicle maintenance. When Muni delivers fewer service hours than scheduled because of vehicle breakdowns, it’s ultimately the same to riders as if there was an official service cut — except it’s less predictable.

Of course, many of the additional budget-cutting moves that Muni made late last year to balance its mid-year budget deficit didn’t happen in time to show up in this report. When the report for the first three months of this year comes out, it could show even more of the consequences of cutting core areas like maintenance.

Earlier this year, Muni learned a similar lesson when it cut overtime spending: Not having operators to fill in for absences also leads to de facto service cuts. Just how bad the consequences of budget-snipping will be for the transit operator won’t be clear until the the quarterly report for early 2010 is released.