Desert Hiking - Water

Desert hiking centers on the issue of water. A person doing strenuous hiking in hot weather may need as much as 2 gallons of water per day to avoid serious dehydration. In addition, water is heavy—8.3 pounds per gallon. The availability of water sources usually controls your trip itinerary. On day hikes, you can carry all the water you need, although it can still be quite a load in the hot summer.

When backpacking, carefully plan your trip so that you pass at least one reliable water source per day. Water sources include permanent or seasonal streams, springs, water pockets or tanks, and water caches placed in advance. It can be difficult to determine whether a water source is in fact reliable, but it's critical, especially in hot weather. Consult hikers experienced in the area, guidebooks, and the land management agencies for information. As you gain experience, you will be able to predict, based on recent weather, whether seasonal water sources will be available.

Don't rely on maps for water source information. Even the otherwise excellent U.S. Geological Survey topographic series maps often show springs that have long been dry and are notorious for showing permanent desert streams where, in reality, water flows only during wet weather.

Always have a backup plan in case a critical water source is dry. For example, you should make sure you have enough water to backtrack to the last source or to change your route to one with more water.

A massive load of water can slow you down enough to force a change in your trip plans. Keep this in mind when first planning your trip. During the trip, you may find less water than you expected, and have to carry more water than you planned. Bring along extra collapsible containers just in case.

Water is scarce; keep it clean. Keep human waste, soap, and food scraps out of drainages, whether or not they are dry at the moment. Never bathe or swim in a water pocket or tank. Even if you don't use soap, you'll still disturb the natural environment by stirring up sand and sediment. Some animals, such as the spadefoot toad, depend on the sediment for successful reproduction.

If water sources are small, take only the water you need for drinking and cooking. In addition, don't waste it. If water is scarce, even brushing your teeth should be avoided. Remember, you're the guest in the desert backcountry; don't deprive your hosts of water they need to survive.

Buy bottles made of high-density polyethylene, polycarbonate, polypropylene, or other plastics that do not flavor water.

Many extended desert backpack trips are only possible if you're willing to carry water for two or three days of dry hiking. Plastic bottles are very bulky, so consider collapsible water containers. These are available in sizes up to 2 gallons or more. The advantage is that empty containers don't take up much room in your pack; the disadvantage is that they aren't as reliable as rigid containers.

Nylon water bags are a good option. The outer shell is made from nylon pack cloth and includes a carrying handle. The inner shell or water bladder is double plastic with a built-in, removable spigot or spout. The nylon shell is slightly smaller than the bladder, so the shell takes the weight of the water. Their capacity is slightly over 2 gallons, and if the bag is not quite filled, it can be efficiently squeezed into your pack. The bladder and spigot can be replaced when they wear out, and the plastic doesn't flavor water.

There are a couple of disadvantages. It's very easy to accidentally puncture the bladder with cactus spines and the like, so in camp, try to hang the bag whenever possible, or lay it on a clean rock or on a piece of equipment. The other problem is that the spigot tends to leak if something in your pack presses up against it. To avoid that, put the bag spigot side up in my pack, then place a drinking cup over the spigot to protect it.

In very hot weather, when your water supply is critical, it's a good idea to carry a number of small containers, rather than one or two large containers. Or, compromise and carry a couple of 1-quart bottles with enough collapsible containers to hold the maximum amount of water you'll need to carry on the trip.

Make sure your bottles have reliable seals. You should test them before the trip by turning filled bottles upside down and squeezing them hard. Test collapsible containers before a trip by blowing them up with air by mouth, then letting them sit for a while to see if they maintain pressure.

How much water should you carry?

There are no rigid rules for the amount of water to carry. Some areas are well watered, and two 1-quart bottles of water should be enough.

In other areas, water sources may be two to three days apart; if the weather is cool (fall, winter, spring), a couple of gallons must be carried. In hot weather (summer), hiking for two to three days between water sources can be deadly and is not recommended.

On day hikes, carry 1 to 4 quarts depending upon hike length, difficulty, heat, and water sources.

On backpacking trips, carry two 1 -quart bottles and a 2-gallon water bag for maximum flexibility and minimum weight or bulk. On extended trips, carry a spare bladder.

If you'll be collecting water from shallow rain pockets, bring along a small bottle or shallow cup with a thin rim. Some people carry large plastic syringes for this purpose.

Duct tape will repair most water bottles and collapsible containers. You can repair a nylon water bag by turning the bag inside out through the spigot.

Keep your water containers inside your pack and insulated by clothing. Bottles carried on your belt or fanny pack quickly become warm and stale. Don't use metal canteens because they heat up rapidly.

Finding Emergency Water

Look for patches of lighter green vegetation in drainages or on distant slopes, which can mark springs. Water pockets often form in dry washes where rock outcrops have trapped an earlier flow of water.

Plunge pools at the bases of dry falls may hold water.

Damp areas in otherwise dry streambeds are an indication that water is near the surface. Before you start to dig for it, check around the corner. Chances are the water will surface either upstream or downstream.

In basin and range country, streams may flow down out of the mountains and disappear into the ground abruptly when the stream crosses the fault line at the foot of the range. Large expanses of open, flat, or domed rock often harbor rain pockets. Sandstone country is especially good for rain pockets. Larger pockets will hold water for weeks after a storm.

Purify all water before use. Even sparkling clear water may contain dangerous organisms. There are several reliable methods for purifying water, including filtration, boiling, and iodine treatment.

Filters are popular because they preserve the taste of the water. They vary in effectiveness, so shop carefully. All good filters remove disease-causing bacteria and cysts, and are excellent for removing visible contaminants such as algae and tiny insects. Make sure you get a filter that uses an active iodine element to kill viruses. Filtering alone can't remove viruses, which are too small for the filter element to trap.

Filters have disadvantages. They are heavy and tend to clog up, especially in murky water. Make sure you know how to field-clean your filter before relying on it.

Desert water often contains bits of leaves and other organic material. A lightweight filter system can be made from paper coffee filters and a plastic filter holder. Don't try to use coffee filters alone—they work very slowly without the support of the holder. Iodine tablets, the optional iodine remover tablets, coffee filters, and the filter holder make up a water purification system that can handle any desert water source and still weighs much less than a regular water filter.

Boiling is a reliable purification method. Boiling kills all viruses and disease-causing organisms at any altitude because the boiling point is always high enough to sterilize the water.

Boiling takes time and fuel, and the water tastes flat afterward. You can improve the taste of boiled water by pouring it back and forth between two containers several times, which aerates the water and helps it cool.

Iodine tablets are also very reliable for purifying water, if used correctly. Follow the directions on the bottle exactly and keep the tablets dry. You may also want to carry a second bottle in case one opens accidently in your pack.

Make iodine water taste better with the iodine remover tablets that come with some brands of iodine tablets. You can also use fruit or sport drink mixes to hide the taste. Both methods use ascorbic acid (vitamin C), which deactivates the iodine in the water. Be sure you've allowed enough time for the iodine to work before adding the remover tablets or drink mix to the water.

Avoid carrying water bottles outside your pack; the sun heats the water and rots plastic bottles.

If you don't have a filter but do have a nylon water bag, you can get clear water when the source is muddy or silty. Fill the water bag and add iodine tablets, then hang the bag so that the bottom corner opposite the spigot (spout) is the lowest point. Allow the water to settle for an hour or more. The silt and sediment will settle into the low corner, leaving the rest of the water relatively clear. Next, draw off water without disturbing the bag.