There's also the issue of the existing infrastructure, versus how many people are out on the playa. Figure attendance is roughly 50,000 people or so, with an average of two people per vehicle. That's up to 25,000 vehicles leaving at a BLM-mandated 1,000/hour - a mandate, by the way, created to ensure that the two-lane road from Gerlach to I-80 still has some room to let the natives, both in Gerlach and "downstream" in Pyramid Lake", actually get out of their driveways and go somewhere that day. Do the math and some people are going to wait for a long, long, long
For those of you from Europe or those just generally not from the area, here's what's basically happening:
There is only one paved road to the Black Rock Desert - Nevada State Route 447
- which is only useful for most people if you take it heading southbound since that's the fastest way to an interstate (that's American for "large freeway") and is also the only direct route to Reno (nearest major airport) and the Bay Area. The total population served by this road is maybe
1,000 (I'm feeling generous), so the road is built accordingly - it's a two-lane highway that's generally straight thanks to the local geography but makes a rather firm point to go right through the middle of what habitation there is in the area (notably, Nixon and Wadsworth). The few towns served by the highway are consequently bisected by it - thus, if the highway gets overwhelmed, it's impossible for residents of the town to cross the street. Also, adding insult to injury, there's not a tremendous amount of freeway or onramp capacity once the highway reaches the freeway (no cloverleaf or anything), so excessive oncoming traffic can cause localized traffic issues on the freeway, too.
In short, Burning Man needs to somehow evacuate over 50,000 people using infrastructure built for less than 1,000 within 24 hours, and do in a way that doesn't paralyze the lives of every single town in the area. No matter how you look at that problem, people are going to have to wait - the only question is whether people are waiting with their keys in the ignition, whether they're waiting for their license plate number to come up, or some other means of queue management. It's either that or try to convince everyone to drive through Cedarville and Alturas to go home, not that they're equipped to deal with any significant traffic themselves.