The key is.......Water, Water, Water.......and more Water. Plus, make sure you have a water filtration device or water purification tablets.
Obviously that is not everything that makes up a 72 hour kit, but for most of us water and water filtration are at the top of the list. Many individuals focus on their gear lists and fancy gadgets, but fail to recognize the importance of water and access to potable water.
Water storage and portage does create some issues. One problem is that water is heavy. You are looking at about 9 pounds per gallon when considering the water weight and container. To help with this carrying weight, drink some of your water immediately. Many agencies and experts feel that it is best to hold off on drinking water initially and wait for up to 24 hours. In my own experience and in talking to other folks who I consider wilderness survival experts, it would seem that it is better to start drinking immediately. There are several reasons for this. 1) The exertion of carrying the extra water weight can lead to increased stress and perspiration. Water inside of you is much easier to transport! 2) Maintaining your existing level of hydration is important. Once you are dehydrated it is difficult to return to a hydrated state. Furthermore, your senses become dulled, your logic is impaired and you may become incoherent. 3) The initial portion of an emergency and/or physical activity will often require more of your body.
A good recommendation is to store 1 gallon per person per day. However, for an emergency kit this would prove to be too heavy. 3 Liters is usually a better recommendation as long as you have additional access to water. If you do store 3 gallons, drink two of them as soon as possible.
Water storage can be an issue. Build up of harmful bacteria can begin in water bottles due to light, heat and duration in a container. A great way to avoid these issues is to store the Coast Guard Water Rations, or water pouches. These pouches are usually good for 5 years and stand up to changes in weather better. If you do store water in bottles, rotate frequently with a maximum of 3 months in between rotation.
In terms of filters, a great way to go are the AquaMira FrontierPro Filters. These filters usually cost under $25.00 and are good for up to 50 gallons. They are small, lightweight and extremely effective. Keep one of these filters in your pack and know where reliable water sources are. This allows you to expand your water capacity.
Another option is to purchase a pump style filter made by Katadyn or MSR. Some of these units can filter 1,000's of gallons of water, but are heavier and bulkier. Many folks also use water purification tablets made by Katadyn or AquaMira. These are extremely lightweight and compact.
Whatever you decide to do, make water your focus and you won't be sorry. The next post includes what I call an adult lightweight backpacking assembly with a list of components. This is my pack for backpacking, camping and emergencies.