I recently shared the news that Sound Transit is removing some of the train cars from its Sounder North commuter rail service due to low ridership. For a variety of reasons, transit riders are avoiding that particular line, reasons which seem to be a result of the poor planning that is endemic to the agency.
That post had me contemplating how much money Sound Transit is sinking into its Sounder North Line. Unfortunately for transparency’s sake, Sound Transit lumps both of its Sounder lines together on financial reports, though we can derive a decent estimate of the cost breakdown for each line from what little information the agency does provide.
Let’s look at Sound Transit’s Quarterly Performance Report for the second quarter of this year. It reports that the average cost per boarding of the entire Sounder Line was $12.05, and there were 760,865 total boardings that quarter. Multiplying these two numbers indicates that the total cost to operate Sounder was $9,168,423.25.
Next we must determine how much of this total amount is attributable to the North Line. A good estimator is run frequency. Each weekday during the quarter in question, there were four trains running each direction on the North Line, while nine trains ran each direction on the South Line. (There isn’t service on weekends or holidays.) So, 4/13th of all Sounder trips were on the North Line.
Applying this ratio to the total cost of operating Sounder, we find that the cost for just the Sounder North Line is a cool $2,821,053.31. And though Sound Transit doesn’t distinguish between the costs of each Sounder line, it does report the ridership of each line separately: for the second quarter, there were 74,560 boardings on Sounder North. This means that the average cost per boarding was a whopping $37.84.
To put this amount in perspective, it would run about $80, or the cost of two passengers on the Sounder, to take a taxi or Uber car from Everett to Seattle. In other words, if it put two passengers in each car, Sound Transit could pay a fleet of taxis to take passengers from Everett to Seattle for the same amount it pays to operate Sounder North. Or Sound Transit could reduce costs by a third by putting three passengers in each car. Instead, Sound Transit insists on corralling commuters into an inefficient and inconvenient rail line.
 Occasionally, scheduled runs were cancelled for maintenance issues, and less often an extra run was added for a special event. These schedule alterations have a negligible effect on the proportion of North Line rides. Indeed, given 13 trips each direction per weekday, we would expect 1,664 total trips during the quarter. Sound Transit reports there were actually 1,662.
 To be fair, it’s entirely possible, if not likely, that Sound Transit’s cost curve for the Sounder train is a function of additional variables, such as number of stops (up to nine in the south and four in the north) or length of the track (about 47 miles to the south and 35 miles to the north). But there is no doubt the number of runs is a huge cost driver, and in the absence of data illustrating the interaction between these other variables and operating costs, I’m comfortable estimating costs based on run frequency alone.
 Fares are $2.75 to $3.50, but hey, at least riders are charged something.