Perform whitewater rescues and recoveries

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1 Objectives On completion of this unit, students should be capable of: determining appropriate rescue/recovery techniques understanding the skills to perform rescues and recoveries understanding the use of mechanical advantage systems to perform rescues and recoveries Background All paddlers will at some time run into difficulty, whatever their skills. The very nature of the whitewater river environment requires the paddler to have a broad range of skills and basic rescue equipment so that he or she can deal with potential rescues of people or the recovery of gear. Even the most prepared paddlers may find themselves confronted with emergencies that can be caused by a range of external influences such as extreme weather conditions, other parties on the river or equipment failure, all of which can create unsafe situations. However if you have well-trained and equipped members to deal with the emergency this can significantly improve the likelihood of a safe outcome. As types of whitewater craft have advanced in design, so have the equipment and methods used in rescue. It is vitally important that river runners practise river rescue through practical scenarios through rescue courses, clubs or company workshops. This is to hone both uses of technical skills and emergency management principles. Rescue categories There are many potential situations that may require a paddler to be rescued. By putting them into categories we can plan, train and equip paddlers to deal with these situations when required. Capsized swimmer In rapids it is common when a paddler capsizes that their equipment will travel down the rapid with them. Sometimes self-rescue is not always completely possible, neither is the immediate retrieval of the swimmer and/or equipment to the bank. Entrapment There are several situations that may trap a paddler. The most common and potentially dangerous is a foot entrapment. This generally occurs in relatively small shallow rapids when a swimmer tries to stand up in a strong current and their foot is trapped in a hole or ledge. The current pushes and holds them in this trapped position. Broach This is a common situation which occurs when a kayak or canoe is washed sideways onto a rock or boulder and the upstream gunwale is pushed down. The water pressure holds the craft on to the rock making it very difficult for the occupants to exit the craft. Vertical pin This is more common with kayaks on steeper rapids and with boats that have pointy flat ends. Creek kayaks have round buoyant ends that tend to pop up and rarely get stuck vertically, whereas play and slalom kayaks tend to follow the current down a hole, ledge or crevice. The pin will occur when the bow of the boat finds the obstruction and the pressure of the current holds both the paddler and kayak in this pinned position. Australian Canoeing Page 1

2 Strainer entanglement Strainers are very dangerous and if a swimmer from a boat gets caught in a strainer the forces of the current on the swimmer and/or boat will hold it fast. The boat and/or the swimmer do not necessarily come out the other side due to the density or position of the strainer. Rescue management process The very nature of rescues will quite often place other members of the group or party in an elevated level of danger. This is why it is very important when a rescue is performed that a management or leadership structure is firmly in place to protect rescuers and other members of the group. It is well documented that many rescuers have become victims themselves. Training is the key to ensuring that when emergencies do occur we are prepared, minimising the risk of further injury or loss to all other members of our parties. There are four main roles in the carrying out of successful rescues: Leader The leader should not be directly involved in the hands on of the rescue because they need to step back and absorb the big picture. This allows them to plan for the What ifs and also to think of plans B and C whilst ensuring the safety of all members of the group. It is important that they delegate the tasks throughout the process Rigger The rigger is in charge of the equipment, setting up rescue systems and the logistics to support the rescue process. It may involve being in charge of a small work team to handle the hauling of the lines Attendant The attendant is quite often the runner and the link to other parties whether they be other members of the group not involved, or initiating communication with emergency services or just to document and maintaining records Rescuer The rescuer is the person who generally makes the contact with the victim. This person is on the end of a tethered line or has waded out to an entrapped person or broached boat. This person should have had formal rescue training and be an experienced paddler as this is the person other than the victim that is put most at risk. The rescue scene It is imperative that the scene of any rescue is managed to offer maximum protection to the victim, rescuer, other group members and other parties. There are some standard safety precautions that should always occur and they are: Upstream safety This involves the appointment of an individual who is positioned to ensure that no other parties should enter the effected rapid and to look out for floating debris. Downstream safety This ensures a safety net is located downstream of the victim, should the victim or equipment suddenly float down. The positioning downstream of manned throw ropes can help retrieve any conscious people. Manned craft can assist with the retrieval of unconscious people and equipment. Ideally downstream safety should be a combination of on and off water safety. Leader position If possible, the leader should be positioned where they have clear vision of both upstream and downstream safety and the rescuer. Communication is then most effective with all parties. If this is not possible the leader should ensure that there are links between all parties in case there is the need to change plans. For the communication to be effective everyone involved should have brightly colored clothing, be equipped with a proper whistle and know the universal hand and paddle signals. Australian Canoeing Page 2

3 Communication Communication on the river can be very difficult due to the noise of the rapids and also the line of sight being broken due to height difference, sharp bends and vegetation and rocks. To facilitate direct communication between party members it is important that groups use predetermined visual and audible signals. The use of a paddle and whistle is a tried and proven way of communicating on rivers. The acceptable international river signals are: Stop: Paddle held horizontal or both arms out to the side. This signal generally means that all in the party should stop and pull out into an eddy and wait Go: Paddle held or arm vertical. This signal should indicate one person could go Go that way: Paddle or arm held at a 45 angle pointing toward the direction to travel The use of whistle blasts unfortunately does not have international recognition. Some organisations use rigger signals, others use their own or some commercial rescue organisation signals. However the use of whistle is very effective and instructors, guides or trip leaders should always establish at the start of every trip what whistle signals will be used so there is no confusion. We should never assume that everyone has had the same whistle signal training. To be able to communicate from a river to the broader community is very difficult due to whitewater rivers predominantly being remote and in steep river valleys. The use of mobile phones and radios does not always provide reliable communication from rivers. The only modern communication that generally guarantees communication to the outside world is satellite phone, which is becoming more common, but the cost is still outside the reach of the average paddler. EPIRBs should be carried into truly remote rivers. Rescue equipment Rescue equipment is only of use to supplement training, knowledge and skills. The equipment will not be effective unless the paddlers know how to use it. Ropes There are many different types of rope. The main rope used for river rescue should float, be brightly coloured and be thick enough to grab hold of and able to be handled without cutting the user s hands. The most common is polypropylene. This is very good for a throw bag rope but should not be used in mechanical systems as the breaking strain is not high enough: 8 mm polypropylene has a breaking strain of 800 to 1000 kg. Rescue ropes should have a breaking strain of at least 2000kg. The only floating rope that meets this requirement is Spectra. Australian Canoeing Page 3

4 Knives Whenever we work with ropes it is very important that all people concerned carry a knife. Due to the potential for rope entanglement the only quick and safe way to deal with this is by having access to a proper knife. Should you need to use a knife to remove a tensioned rope from around someone the safest way is to ensure only the rope is cut, and not the person, by using a hook or parachute knife rather than an open bladed knife. These knives should be carried on your PFD for easy access. Open bladed knives have their place, especially in rafting, where there is the potential for a person to be trapped under the floor of a raft, released by cutting the floor with an open blade knife. Karabiners Alloy karabiners tend to be preferred for weight and resistance to rust. The choice of open or screw gate is one of personal choice. Paddle clamps These are very useful items that allow for a karabiner to be placed onto the end of a paddle that can be extended with a rope attached to a end loop or broach loop of a pinned boat. Pulleys Pulleys are useful for use in mechanical advantage systems to lessen the friction of a system. They also have uses in lowering systems and zip lines. Prusik Loops Prusik Loops have many uses, the main one being for setting mechanical advantage systems such as Z drags. They are also very convenient for quickly attaching boats to branches, etc. Knots When working with rope it is important that we can perform a range of knots that can be used to establish various rescue systems. The following knots are the minimum that canoeists understand and can demonstrate: Figure of eight The figure eight has many purposes. As an end line knot it is the recommended knot for tying off the running end to stop rope passing through a pulley or belay device. Figure of eight on the bight By forming a bight with the running end of the rope, an easy, reliable end line loop can be formed which is perfect to attach karabiners to. This is the preferred method to attach to an end loop, D ring or anchor system. Double figure of eight on the bight The double figure of eight on the bight forms a double end line loop which is a perfect knot used to set up multi point self equalising attachment for wrapped rafts or broached canoes. This application does need considerable rope. Australian Canoeing Page 4

5 Double fisherman This knot is primarily used for the forming of Prusik loops. The knot is very strong but can be very difficult to undo once it has been loaded. Prusik knot The Prusik knot is primarily a climbing knot, often referred to as a friction knot. A rope cord or sling (usually of smaller diameter than the main rope) is wrapped around the main rope in such a way that the Prusik cord grips the main rope and will not slide under tension. When there is no tension on the knot, it slides freely up or down. Tape knot Probably one of the most popular knots, this knot is known by many names: follow through, overhand bend, overhand follow through, ring knot and water knot. It is compact and lends itself to many of the needs when using tape. For the most part, many slings are fastened together with this knot. It is an excellent knot for fastening webbing together. No knot This knot can also be referred to as a tensionless anchor. It is the preferred knot for attaching tag lines to riverbanks as it provides a very quick, secure, and easily identified knot that can be undone under load. Pull through Butterfly knot This is a mid-line loop knot that can be loaded in any direction and is good for attaching one system to the middle of another such as pig rigs or adding vector loads onto ropes. Munter hitch Also known as the Italian hitch, this is a hitch that can be used on a karabiner to control descent of a swimmer. The hitch can belay in both directions. Load Brake Brake Rescue recovery methods The decisions relating to what method of rescue should be used for any particular rescue involve being able to prioritise the need for urgency weighed against the risk required to be taken by the rescuer. You need to consider whether the victim s head is up or down, the body submerged or not. These two considerations will dictate the urgency due to the ability for the victim to breathe or the rate that hypothermia will take effect. The process that should be used is an easy to hard or dry to wet option. The adage that is used is: reach: from shore with pole, paddle, stick or hand throw: a line or throw bag or some other flotation row: the use of boats to gain access to victim go: to the victim in the water by swimming, wading or a rope system Load Australian Canoeing Page 5

6 tow: the victim by tethered swimmer or rope systems with rescuer helo: the use of helicopters Some of these options are risky, as statistics show a third of those that have drowned on rivers have done so in trying to rescue someone else. This is why it is very important that rescuers clearly know their limitations, which of course can only be gained through effective professional training and experience. Reaching The use of paddles with paddle clamps on them is an effective way of placing ropes and karabiners onto end or broach loops of boats. It also can be used to access a rescue PFD attachment of a trapped victim in a vertical pin or other entrapment. Throw ropes One of the most important pieces of rescue equipment is the throw rope. The throw rope is very suitable for shore base rescue, particularly for swimmers in rapids. It also can be used to get a line across the river or to a victim trapped mid stream. Most throw bags are between 12 and 20 meters in length. Successful use relies on good secure positioning of the thrower, which would enable the retrieved swimmer to pendulum into an eddy below the thrower. It is important that the thrower gets eye contact or the attention of the swimmer prior to throwing. The rope should then be thrown directly over the top of the swimmer. The swimmer then should grab the rope with both hands, hold it against their chest close to their neck and let the current do the work. A throw rope should never be tied off. Tag and zip lines Tag lines are lines that are perpendicular to the river and can be secured or not secured to permanent anchors. They have a wide range of uses from stabilising an entrapped victim to accessing and retrieving victims. Tag lines and the use of wading or traversing the rope lines are common in rescue. It is very important that these lines are not tensioned mechanically. This is due to the large vector forces that are placed on the rope and anchors. No knots are the preferred means of anchors, as they allow for the rope to be released under tension and are quick and simple to use. Fixed lines that require two way travel must be set at right angles to the current otherwise travel in one of the directions will be very difficult. If only one-way direction is required the tag line principle should be converted into a zip line. This involves having the rope at an angle to the current so that the current assists with the direction of travel. Some tag lines can be weighted to allow the rope to sink. This enables the rope to pull a trapped foot upstream (snag tag line). For a zip line to be very fast and effective use the current to generate movement. The angle needs to be as sharp as possible and the rope line must have mechanical tension in the system (Z drag). The zip line is the only fixed system that can have mechanical tension applied. This is due to the rope line not supporting the weight of the user and only acting as a guide to direct the person s travel, therefore not generating excessive vector forces. Strong swimmer rescues Only a rescuer having a proper rescue PFD can attempt this type of rescue. The rescue PFD allows for a line to be attached to the PFD giving the rescuer the option to release if they get into trouble or be swung back into the bank if they miss the target. At no times should this tethered line be tied off at the bank, neither should a rope be tied to a victim without a release system. This method provides for a rescuer to access a victim and to either support the victim in a pendulum return to the bank or stabilise the victim until further help can be provided. Tow systems Tow systems have become more popular over the years. It has become common practice for paddlers to use their tethers on their rescue PFDs as towlines. It should be noted that this is not what the PFD system is designed for. It can be done successfully, but users need to know their limitations and the potential dangers. In whitewater the potential for a boat being towed to be on one side of an obstacle and the rescuer to be on the other is real, and should the rescuer capsize pointing downstream it may be very hard to access the release system. The use of this Australian Canoeing Page 6

7 method is not recommended in whitewater. The use of other tow lines, especially those waist systems with the release below the PFD should not be used in whitewater in any circumstances due to the difficulty of accessing the release. Ten person pull This is essentially using as many people as you can find to pull on a rope. This is used as the first option when trying to move a stuck boat or raft. Vector pull The vector pull involves securing a rope at both ends and loading the rope in the middle to generate vector forces on the ends to try and move trapped boats. This can also be added onto established Z drags. Mechanical advantage systems The use of mechanical advantage systems is best used for the recovery of wrapped boats. The most common system is the 3 to 1 Z drag. There are situations that may require a tensioning or raising system setup to release a victim who is in a pinned boat. It is important we understand the progression from easy to complex systems and also the limitations on the equipment we carry with us on the river. The rope that should be used for mechanical advantage systems must be strong enough to cope with the loads being generated. If we work with a 10 to 1 safety factor to generate a force of 200 kg on a rope we must use a rope with a minimum breaking strain of 2000 kg. The majority of polypropylene ropes used in throw bags are rated at between 800 to 100 kg and are not suitable to be used as rescue ropes other than throw ropes. Ropes such as Spectra with polypropylene sheaths tend to be the only floating ropes that are suitable for these tasks. Many boaters carry static kernmantel climbing rope that can be used for rescue systems. It should be noted that this type of rope does not float and care needs to be taken not let this rope get near a victim as it will sink, with the potential to tangle with the victim s body and limbs. The common systems used are 2 to 1, 3 to 1 or 5 to 1. Systems that use a greater advantage than this will be overloading the ratings on the equipment that is carried by canoeing parties. Telfer lower This is a system that combines many ropes and considerable hardware. It is a system that has the ability to have control over lowering downstream and raising upstream as well as having the ability to control positioning left or right of a boat or tethered swimmer. The system is constructed with a tag line that is fairly slack positioned well upstream of the objective. A karabiner chain is then placed on a pulley on the tag line. Separate lines are then placed to river left and river right from the chain. The main lowering and raising line runs through a pulley on the karabiner chain from the bank to the boat or swimmer. Lowering is controlled through a descending device or a Munter hitch on an anchor system. To convert the system to raising, a Z drag would then be applied at the anchor. Load Australian Canoeing Page 7

8 Group equipment The amount and type of rescue equipment that should be taken on a river trip will vary depending the river and the types of boats and skills of the participants. Some basic principles should apply to all white water paddlers who are responsible for their own safety and that of the group members. Equipment that is best carried on you includes: whistle safety knife throw rope (attached on either waist strap or stored in PFD) 2 karabiners (minimum) 2 Prusik loops If all trained paddlers carry this equipment on them then the combined equipment of the group would be able to deal with most situations. The additional gear required is the rescue rope, which would be carried in an identified boat. Glossary Boil line: the line below a stopper that separates between the force going upstream and force going downstream Broach: a craft is sideways to the current and the force of the water is holding it against rocks or trees Broach loop: a loop or fitting located in front and behind a paddler in a kayak, and accessible by the occupant to attach a rope line in the event of a broach or pin Buoyancy: a buoyant boat is less likely to become trapped: fit the air bags Downstream: the direction towards which the river flows Eddy: backwater or slack water usually on inside of bend or caused from obstruction or rock Eddy line: the line that divides the main current and the eddy Entrapment: when any body extremity, usually a foot or leg, is caught against the river bottom by force of the current Haystack: a large standing wave Hole or Stopper: powerful upstream current formed from water flowing over a large obstacle Karabiner: a spring loaded snap hook made of alloy or steel for attaching ropes or slings, and also may be used as a pulley PFD: Personal flotation device Prusik loop: A loop of rope that when fixed onto a thicker rope will grip when the load is applied (Named for its originator, Dr Karl Prusik) Pulley: a device to allow rope to move through a bend with minimal friction Rescue PFD: a quick release harness built into a PFD to allow a rope line to attach to the wearer with control of its release by the wearer River left: when facing downstream the left side of the river River right: when facing downstream the right side of the river Sling: usually webbing made into a loop to be used as rigging to secure anchors Strainer: a logjam or sieve of branches through which current flows Throwbag: a bag that contains floating rope for rescue Upstream: the direction from which the river flows Vertical pin: the force of the current holding a boat into a fixed position generally with the bow being held under a rock or ledge Weir or low head dam: uniform feature all the way across the river causing a stopper that has no exit Wrap: the force of the current holds a boat around a boulder or on to the riverbed References Bechdel L, and Ray S, River Rescue, Appalachian Mountan Club, 1997 Ferrero, F, White Water Safety and Rescue, Pesda Press, 1998 Walbridge, C and Sundmacher, W, Whitewater Rescue Manual, Ragged Mountain Press, 1995 Australian Canoeing Page 8

9 Questions 1. What are the four main roles in performing rescues? 2. What are the main safety considerations that should apply to the rescue scene? 3. What is the only fixed line system that can be tensioned mechanically? 4. What are three requirements of a throw rope? 5. Why is polypropylene rope generally not suitable for rescue systems? 6. Why do we need to place on water downstream safety in addition to on bank safety? 7. What is the preferred knot for anchoring a tag line and why? 8. What piece of equipment should be carried on you if you are working with ropes? 9. Why should a tag line not be tensioned mechanically? 10. What the adage that assists with ordering the safest method of rescue to be performed? Australian Canoeing Page 9