Yes, looking at their website they do have a dump station and therefore fresh water should also be available.
http://www.albertaparks.ca/jarvis-ba...s/camping.aspx
Most provincial parks do; if not right in the park at least nearby. For example a few of the campgrounds west of Bragg Creek do not have water and dumping; however at the entrance to the park there is a dump/fill station beside the information booth.