Even before ST3 passed, the Seattle region was spending more per capita on new buses, trains and other new transit projects than any other major city in the country, the Seattle Times reports, and once ST3 kicks in, spending on transit projects will rise from its 2015 rate of $393/person to close to $500.

Counting operating expenses — the costs to run a transit system but not build anything new — New York spends the most per capita. But it also has the nation’s largest and most-used transit system. Seattle comes in third because new projects here are expensive.

One reason the region is spending so much: it costs a lot to play catch-up. In the late '60s and early '70s, Seattle voters turned down major transit measures. Fast forward to the last two decades: voters have approved three such measures. Catching up on infrastructure work in the 21st century is more expensive than doing it in the mid-20th century, when costs were lower.

Another reason transit costs more in greater Seattle: tunneling. In regions where tunnels are not necessary for transit systems, projects cost a lot less (Denver, for example). Seattle is not so lucky. Transit projects require some digging, and that costs megabucks.