Always carry plenty of water (five liters is a good amount to plan on for a full day of hiking without the option to resupply, although you may get by with three or four during the winter or in cooler weather) and have the capacity to carry more – water bladders and soft bottles are light and take up no space when not filled.
When hiking in the desert, especially in warmer weather (i.e., not in the winter months), it’s very important to stay hydrated. If unsure, always err on the side of bringing more water! Five liters a day may be enough for drinking; but if camping overnight, allow several more liters for cooking and cleaning. Camping within reasonable walking distance of a water source is helpful here – instead of needing to carry water during your hike for the night and the next day, you can use water from the source and fill your pack in the morning before leaving. However, you should not camp too close to natural streams and springs in order both to protect the environment (following Leave No Trace practices) and to avoid disturbing locals (both people and animals) who might come to use the water source.
As anywhere else in the world, you have two basic options for obtaining water: getting it from inhabited areas (whether from a tap, in bottles from a store, or even from a village’s well) and getting it from natural sources such as springs and streams.
While hiking in areas near towns, the easiest and safest way to obtain drinking water is to do as locals do – buy it in bottles, or just drink it straight from the tap. When passing through areas without villages or permanent inhabitants, you’ll want to pay special attention to the location of available groundwater sources.
Perhaps surprisingly to those who may think of Jordan as a desert country, and despite the country’s serious water shortage, there are fairly regular sources of natural water throughout the country’s western mountains and gorges, often in the form of wells, springs, or even perennial running streams. It is this water (supplied by the rain caused by the mountains’ high altitude and the large watershed of many of the streams) that allows Bedouin to live in what might otherwise seem like thoroughly desolate desert.
The availability of water may not be extremely frequent, but you should normally be able to find it at least once per day on or near the trail. The lengthiest section where water is difficult to find, where you may want to arrange water drops or caches, is from Rum village to Aqaba.
Many locals do not drink the tap water in Jordan because it is not pumped constantly through the pipes to supply centers; when it is not being pumped, contamination might seep into the pipes through any breaks. Bottled water is almost universally used for drinking, though it’s certainly possible that you might drink only tap water and have no problems.
Backpackers who are accustomed to back-country hiking in developed countries may be used to using water treatment methods such as pump filters which eliminate bacteria and protozoa, but not necessarily viruses. In Jordan, we do recommend using one of the water purification methods recommended by REI for international travel. This could include chemical treatment, a UV treatment like a Steripen, or a more thorough filter than those normally used in backcountry areas of the developed world. Boiling water is also a safe option, though a very inefficient one.