If you are going to spend time anywhere along the Colorado River basin, but in particular, Yuma....then you should invest in a Reverse Osmosis System. You can count on $350 to $500, depending on the output of the 3 filter system. The entire system will fit in a medium sized Rubbermaid type container, and can be plumbed to sit on the ground outside of your RV, or if you have the space, in the basement area. I opted for outside, it makes changing filters much easier and there is no water to mop up. You can get information from The RV Water Filter Store, or at the Yuma Marketplace.
http://www.rvwaterfilterstore.com/WCRO.htm
Regards
Gemstone