The dogs and I drink bottled water. My black tank is full the clean water tank was a problem. I filled up in Hanover PA on May 3rd and filled up a 5 gallon water cooler. I used the camper water washing dishes (paper and plastic helped reduce consumption of water in the camper's tank) showers (navy showers) and toiler use.
Some vandals / thieves destroyed the water supply at the house I am staying at and I had to wait to get it repaired so that full tank and extra 5 gallons I brought from PA was a wise decision. On Monday the 10th I was low on water and just added the water in the 5 gallon container to my camper supply and probably had a few days left when the water company restored water service the following day. I am guessing that I could have made it till today or maybe yesterday if the water had not been restored. If you don't have a gadget called a water thief you may want to look into it. Using bottled water for drinking means you do not need to be as picky where you get your water. Using a 5 gallon cooler may increase your chances of getting water, in some cases a place may be willing to give you 5 gallons but may be reluctant to let you fill up what they think is 100s of gallons of water. Even though your tank may only hold 40 gallons someone may think it holds 100s of gallons