Every year I lived in a different location but the shortest was a bit more than half an hour trip by bike and I could only safely manage a single gallon. Usually though we'd get water when we hitchhiked into town as we could get more at once. Both of these sources came from water resupply points for trucks but no on cared if you filled a few gallon containers. Rain water was also usable in many cases but we avoided drinking it. We went out maybe once a week or so?