Southern Utah boondocking: how long do roads take to dry?

A good question. I have worked around bentonite in Wyo and SD. Sometimes you can get stuck on a flat road with chains on all 4 wheels.

Sometimes you have no choice but to wait for the weather to dry out. It depends on the temp, usually low humidity and the wind. If a shower is brief, the sun and some wind can dry out the surface in a couple of hours, even 45 minutes. Sometimes you can travel in the early morning when it is frozen.