The federal gas tax — 18 cents per gallon — is due to expire at the end of September. If it vanishes — as some politicians would like — a lot of federal funding for transportation (and Metro) goes with it.
The above video helps explain the gas tax and where the money comes from and where it goes.
The video was produced by Pavia Systems, a Seattle-based firm that specializes in training works in the asphalt industry. I think it’s a pretty fair explanation, but obviously Pavia benefits from highway spending.