Water is even heavier than food and more needed. Filters are of the most importance to me. Even with food, yes you need some but mostly I think having ways to secure some along the way is better than trying to carry 45lbs of canned ham....a 10 hour Drive is going to be a long way ON FOOT, you could be talking A MONTH's walk, maybe two.
food and water is going to be the main problem-no way can you carry a month's worth of food.