I think a more appropriate question here might be, "where are you camping?" If they have the water turned off that must mean there is a chance the water will freeze underground. Where I am in WI today is the first day we've been above 32 degree Fahrenheit in well over a week. In all honesty if you are somewhere where the temps don't get below freezing or only go below freezing for a few hours the water in your tanks shouldn't freeze, but water in the lines may freeze. I would think if it is cold where you are perhaps you should turn the heat up slightly so it runs for a long enough time to allow some heat to build up in the basement area, perhaps then it will thaw it out if it is indeed frozen.
Jim & Linda Tator
2013 Crusier CF34SS GMC 3500 8.1L Dually
154 nights in 2013 - 4,370 miles
178 nights in 2014 - 5,082 miles
365 nights in 2015 - 6,040 miles