I hear a lot about fuel system water and wax on forums, but have never seen either in our fuel.
It might depend on the diesel fuel available in different parts of the country. We've been running two diesel trucks and 3 diesel tractors for 40 years now, and I don't believe I've ever changed the fuel filter in any of them more often than once a decade. And never once has there been any sediment or clogging of the filter.
Most of the filters bowls are clear enough that you can see if there is anything accumulating in the bottom there like water or waxes. I've never seen either. Plus, I've several times now over the years put fuel samples out in the barn in real cold weather just to see what would happen and never seen any change in the fuel.
Mountain weather can be cold but the climate is dry. We use regular automotive diesel from any of the local filling stations, nothing special. Usually the pickup has half a dozen or more 5 gallon containers kicking around in the back that we try to keep filled.
It's petrol diesel....although Colorado grows a lot of corn, you don't see bio-diesel much, or at all.
I've heard there's a private station in downtown Denver that sells bio-diesel, but think you have to be a member and make an appointment to buy from them, so it's not a popular fuel. Most of us just run pump diesel. It's cheap enough.
We do run an additive sometimes - especially in the summer we use XPD when we are going to be working the machines hard or on long truck trips. I don't know if it does anything worthwhile, but it doesn't seem to hurt.
rScotty