How do I get my dog to stay out of the cat food/litter boxes?

My dog never ate feces until we got the basset hound. The basset hound came from a less than ideal situation, where she was often locked up and I believe that is where the coprophagia came from. I feel like it was a learned behavior brought on by poor treatment and confinement. Anyhow, my older dog never did this until she saw the b/h doing it. Now it’s a constant battle to keep them away from any kind of poo.
I keep the cat food on a table in the cellar. I don’t free feed my pets, so the cats only get as much as they will eat in one sitting. Still, my older dog (although she is small), believes she is a goat and will jump up and/or climb damn near anything. The table doesn’t thwart her at all. The litter boxes are on a different, taller table in another room… but she jumps up there with ease, as well. Scooping the boxes every single time my cat goes to the bathroom is not likely to happen, but of course they are cleaned daily.The tables solve the problem of the basset hound getting into anything, but I have no idea what to do with the jumping dog.

My house has a very open floor plan, so I can’t just shut a door and stop thinking about it. The only rooms that are easily closed off in this house are the bedrooms and the bathroom. Everything else has an archway. These are dogs, not puppies… I really want to be able to put the baby gates away someday.

Any ideas?