[matt_holden]

The 2015 federal transportation bill allocates $48B to transit over 5 years and $205B to highways.

I've never understood why people frequently describe transit spending as a "government subsidy" but would never say the same thing about the much larger highway spending.

If you don't insist on adding tolls everywhere to make highways break even, why hold transit to a higher standard?

[strictnein]

The federal gov collects $30-$35 billion in taxes and fees for the Highway Trust Fund. 5x that number covers most of the $205B.

[icodestuff]

Defense, repurposability, and capacity.

Eisenhower had two sources of inspiration when pushing the interstate highway system. The well-known one was seeing the autobahn in Germany, but the second one was an experiment he was put in charge of in 1919, to see, using the existing US highway system, how long it would take to get a military convoy from one side of the country to the other. The answer was 23 days, with many bridges broken and having to be repaired, with an average speed less than 6 mph. This was obviously inadequate for defense purposes, so even if the most common purpose today of the EIS is private car and commercial truck transport, it was worth building for its defensive role.

Repurposability: the EIS is useful in more ways than HSR would be. HSR is useful only for passenger trains. The EIS works with cars, cargo trucks, tanker trucks, buses, tanks, and in an emergency many parts can be used as runways. In addition, it's connected with the rest of the North American road network, something which would not be true of CA HSR. The best you could get would be intermodal stations, probably at the terminal stops. HSR can't carry freight of any type, and the tracks are meant to be grade separated from the existing freight rail network.

Capacity: At the peak hour, 12,000 people cross the bay bridge westbound vs 28,000 through the BART Transbay Tube westbound. Seems like a win for rail, right? That's with 2.5 minute headway on packed commuter trains feeding from 4 different lines. HSR trains won't have the capacity of BART trains, nor the frequency. Even if each individual's trip is faster, the total throughput is lower. CA HSR specifies 900 seats on a 12-car train (or rather, 450 seats on each of 2 6-car trains which can be joined together). Just to have the capacity of I-5, (which we'll take to be 2/5 of the Bay Bridge capacity for simplicity (2 lanes vs. 5)) there would need to be a train every 11 minutes 15 seconds. Worse, to meet the "expected" ridership of 33.1 million people/year, trains will have to run with an average of 708+ people, assuming the trains run 24/7 (which seems extraordinarily unlikely).

In terms of construction costs, a rough estimate puts the cost of the 375 miles of interstate freeway between SF and LA at $4B (assuming costs of the entire EIS were spread evenly over every mile, but they weren't; the actual cost was lower, excluding the bay bridge, which is tolled). HSR is currently trending towards $62B. Ongoing subsidies are, using the same metric, $321M/year vs. ??? The HSR group claims it will break even before phase 1 completion (they estimate millions of people/year want to go between San Jose and Bakersfield, which seems pretty ridiculous), and be operating-and-maintenance profitable throughout in 2029 when the SF-LA line is brought online. It's hard to find in the 2016 business plan, but the O&M estimates are there: ~$1.1B/year in 2029 (excluding trainset lifecycle cost averaging). The state is on the hook for all of that that doesn't get covered by fares.

So that's ultimately why we should hold transit to a higher standard - more uncertainty, less utility.