I have 40 MP-1 tabs in my BOB, along with a Katadyn ceramic filter, cloth and coffee filters for get the big gunk, 2- Stainless Klean Kanteens (for boiling), and a 25oz TI pot and 12oz cup.. There is also a 10x10' plastic drop cloth for rain collection or additional shelter.
My pocket kit has 8 MP-1's, 2 1qt water bags, plus fire starting materials for water boiling.
In this area, I'm next to a river, and less than 1 mile from a 40+ mile long lake. Plenty of creeks, and ponds in my area. Finding water is not a problem I'm .overly concerned with unless we get a major weather change.