First, I wouldn't assume that is the only water, they are pretty crafty creatures and their lives depend on finding water. Even if it is, a mile is nothing for mule deer.
From there, we're a bit out from the main rut so it wouldn't surprise me that you aren't seeing them on the does.
I agree that the does are where they is good food, water and reasonable security right now and the bucks will find them at some point but they aren't going to poke their noses out in the open during daylight until they have a really good reason to do so. Even then, I have followed groups of does in the middle of rut and there were no bucks on them, likely due to none of them in or near heat.
Sounds like you have a good spot, it's just a question of timing.