I am shocked that I haven't seen anything related to water sources. I would definitely have a water filtration system in my top 5 items to have for a backpacking trip. I have an MSR water filter and it's perfect (https://www.amazon.com/MSR-MiniWorks-Microfilter-Purifier-System/dp/B078T9Z5N9/ref=sr_1_1_sspa?keywords=msr+water+pump&qid=1550076128&s=gateway&sr=8-1-spons&psc=1)