As with all of the CO facilities, you will need to call just prior to arriving to be sure of current COVID and fire ban status.
The SP has several loops. Some have vault toilets and no electric. Most facilities won't be open, as in most of the CO SPs. The flush toilets should be open, but I would not expect any of the close quarters facilities to be open.
Fires are unlikely to be allowed, but we have had rain recently, so it could change.
There are some loops with electric near the office. The sites further out are dry (or were the last time I was on that end). I think they were going to install electric at some of the boat ramp loops, but that had been a years long project.
There is precious little shade in any campground at the lake. The sun can bake you up there. There are shaded dispersed sites in the woods with no services.
Dump Station: Frankly I cannot remember if they even have one. I usually make that short trip and dump after the drive. I can tell you that most all dump sites in the state are only open to campers. We have called lots of them with a common response. "We are not allowing non-guests to dump."
PS the Canyon is below the dam. It is forest service land. (a separate fee area) Fly fishing and tent/small camper camping.