I'm willing to answer some of your questions on the open forum.
In the areas I fish, I have caught sturgeon in water from ~12' to 60' deep. If one is fishing the river (as opposed to the slower current in one of the many reservoirs) they tend to be found in deeper holes (they don't need to fight the strong current); however, if one is fishing one of the reservoirs they do not need to be in a deep hole, so there is a much wider range where they can be found. Because they tend to be in schools and they move around it is extremely helpful to have side imaging to be able to use to locate the sturgeon.
In Idaho, it is illegal to remove a sturgeon from the water, so we use various landing tools to help bring them alongside the boat. Here are two of the ones that I have made and also the tool I use to quickly measure and release them.
If the sturgeon is over ~4' we toss the anchor rope (it is attached to a floating cushion) so that the sturgeon doesn't get wrapped around it. We also raise the prop so that the line doesn't get caught in it.
Speed to fish is zero (one anchors up and fishes on the bottom). I use from size 6/0 to 9/0 barbless (Idaho law) hooks.
One must use a rod, reel and line that is heavier than one would ever use in Utah. I use rods that are rated anywhere from 100 to 120 pounds. From a boat, I prefer a 6 or 7' long rod, but from shore I use a 10' or 12' long rod. Some reels that we use are:
I use (depending upon the capacity of the reel) 65 pound PowerPro line and 50 pound soft Dacron for leader, or I use 100 pound PowerPro line and 80 pound soft Dacron for leader.
Idaho law requires that one rig like this:
They can be caught any time of year and I'm not sure one time is better than another. I prefer to fish from around March to mid November. It is miserably cold to fish for them (especially from a boat) during the winter months and it gets extremely hot in Idaho during the summer (which is hard on the angler and also the sturgeon -- to be landed in warmer water).
The above is strictly my opinion and if you want to ask further questions please PM me.
I would add one caution for everyone wanting to head to Idaho and fish The Snake River from a boat. Some areas are safe to use a prop boat, some areas are only safe from a heavy-duty jet boat, and some areas are not safe from any type of boat. Even in the areas that are safe for a prop boat there are numerous dangerous rocks and sand bars just under the surface. I am extremely hesitant to use my boat in any areas that I have not received input from others who have already boated the area.