How to cross a river.
River and streams can be shallow or deep, slow or fast moving, narrow or wide. It is essential to plan the best approach to crossing, especially if you are not a strong swimmer or have to get equipment over to the other side. First, make a reconnaissance and see if there is an easy crossing place. If possible, view the water from high ground or climb a tree to get a clearer view of what you are up against.
Sometimes a river divides into channels and it is safer to cross over two or three narrow channels rather than attempting to cross than a wide river. If there is a sandbar, select a place upriver so the current carries you to the sandbar where you can rest before completing the crossing. Be wary of soft muddy ground and sinking sand if you climb up onto a sandbar. Generally, the rule of thumb for crossing a wide, slow flowing river is to swim across the current at a 45–degree angle to best use the current in your favour.
To swim across a deep, fast flowing river (even one with rapids) it is best to swim with the current rather than trying to fight against it. You will lessen the chance of being pulled under if you keep your body horizontal to the water. In fast, shallow rapids, the best technique is to lie on your back with your feet pointing downstream using your hands as fins against your hips. This increases buoyancy and enables you to steer away from obstacles. If the river is rocky, keep the feet up to avoid bruising them or hitting rocks
In deep rapids, it is best to lie on your stomach with your head pointing downstream, keeping the body angled toward the shore whenever possible. Watch for obstacles and be careful of backwater eddies and converging currents as they often contain dangerous swirls. Converging currents occur where new watercourses enter the river or where water has been diverted around large obstacles such as small islands. If you are sucked under in a swirl or eddy, the body will be whirled around as if it were in a washing machine. To escape this, curl into a ball and the current will literally spit you out. If you don't curl up you will never escape and just be whirled around until you drown.
It is also important to assess the difficulties across the other side of the river before attempting a crossing. Look to see if the opposite banks are too sheer, if there are thick mud deposits and if there is white water swirling around rocks. In tropical areas, watch out for crocodiles, hippos, alligators and other dangerous animals.
Watch out for hazards such as a ledge of rocks that crosses the river. This often indicates dangerous rapids or canyons, a deep or rapid waterfall or a deep channel. Never try to ford a stream directly above or even close to such hazards.
You may sustain serious injuries from slipping or falling on rocks. Usually, submerged rocks are very slippery, making balance extremely difficult. An occasional rock that breaks the current, however, may help you.
Be particularly alert if crossing an estuary of a river. An estuary is normally wide, has strong currents and is subject to tides. These tides can influence some rivers many kilometres from their mouths. Go back upstream to find an easier crossing site. Try and find another place to cross if there are eddies in the water. An eddy can produce a powerful backward pull downstream of the obstruction causing the eddy and pull you under the surface. If the water temperature is very low, do not attempt to swim across a stream or river as this could be fatal. Try to make a raft of some type. Wade across if you can get only your feet wet. Dry them vigorously as soon as you reach the other bank.
Remember that deep water sometimes runs slower than shallower water and is often safer to cross.
If there is no choice but to cross a swift, treacherous stream you need to reduce the water's pull on your body, so remove all clothing, except footwear (protects your feet and ankles from rocks and provides you with firmer footing). If you have no pack, make a tight bundle of your clothes wrapped in a shirt and tie the arms so they form a "sling". Place this sling over the head and place one arm through it. Make sure you can quickly get the sling off if you need to. If you have a pack, carry it high up on your shoulders and be sure you can easily remove it if necessary. Not being able to get a pack off quickly enough can drag even the strongest swimmer under.
Using a strong pole about 3 inches (7.5 cm) in diameter and 8 feet (2.1 – 2.4 meters) long (see above diagram) will help you ford a stream. It is a good idea to tie the pole to one wrist so you will not lose it if you slip and fall in. Grasp the pole and plant it firmly on your upstream side to break the current. Plant your feet firmly with each step and move the pole forward a little downstream from its previous position but still upstream from you. With your next step, place your foot below the pole. Keep the pole well slanted so that the force of the current keeps the pole against your shoulder. Cross the stream so that you will cross the downstream current at a 45–degree angle. Using this method, you can safely cross in currents usually too strong for one person to stand against. Do not concern yourself about your pack's weight as the weight will help rather than hinder you in fording the stream.
If there are other people with you, cross the stream together as shown in the above diagram and ensure that everyone has prepared his or her pack and clothing as outlined above. Position the heaviest person on the downstream end of the pole and the lightest on the upstream end. When using this method, the upstream person breaks the current and those below can move with relative ease in the eddy formed by the upstream person. If the upstream person is temporarily swept off his/her feet, the others can hold steady while he/she regains his/her footing.