In a small bowl, combine soup and water until blended. Pour half into crockpot. Cover and refrigerate remaining soup mixture. In a bowl, combine the egg, breadcrumbs, Parmesan cheese, parsley, garlic powder, onion powder, salt if desired and pepper. Crumble beef over mixture and mix well. Shape into a loaf; place in crockpot. Cover and cook on LOW for 5 hours or until a meat thermometer reads 160F. For gravy, place reserved soup mixture in a small saucepan; cook over low heat until heated through. Serve with meat loaf and mashed potatoes if desired.