A highway is never a 'transit' project
Both former Mayor Steve Adler and Mayor Kirk Watson have justified their support for the I-35 expansion by arguing that it will support public transit. Specifically, they’ve said the four high-occupancy vehicle (HOV) lanes planned for the new highway represent a big opportunity for expedited bus travel.
“I-35 could and should also play a big role in our transit goals,” the Watson campaign told me in a statement last year. “Outside of Project Connect, I-35 could be the largest transit project for Austin. Kirk supports creating managed lanes for Cap Metro buses, similar to what we currently have on Mopac, which would put us in a better position on how we are currently using the road."
There are a few problems with this thinking. The first is that HOV lanes don’t really work. Enforcement is extremely difficult, which leads to them often being just as congested as the general purpose lanes. So it’s likely that buses relying on HOV lanes on I-35 will spend much of their time stuck in traffic, hardly offering a compelling alternative to driving for suburban commuters.