Team dynamics (swift water)
Swift water creates special needs for the ways in which teams interact and makes some techniques common in other disciplines less effective. The "pass the rope bag" technique frequently used in the United States desert southwest is not recommended. The "rope teams of two" technique is preferred for swift water descents.
Contents
Rope teams
In general, each canyoner with a rope should always be in charge of that rope. Rope carriers usually form a rope team with one or more canyoners who do not carry a rope and who will assist them in their role. Each rope team will be in charge of the setup, management, and pull down of their own rope. Rope teams will take turns setting up the rappels and leapfrog down the canyon, such that while one team is pulling down a rope, another has already set up the next rappel, and another team may be looking for the next anchor further down the canyon. Each team is in charge of a different rappel station and will stay in charge of that station from start to finish. This ensures everyone has an active role in the descent and serves to narrow the responsibility about possible damages to the rope; if a rope is damaged, it will be because the team in charge did a poor job of managing it.
Communication
Swift water presents difficulties for team communication, as water muffles sounds, and waterfalls impede visual contact. Waterproof radios can be useful but not always available or reliable. Visual signals are only possible when in direct line of sight, which often only occurs when out of danger. Whistle signals are the usual communication mechanism in swift water descent. There is no universal code—simply agree on one standard for your group at the beginning of the descent. The person managing the first rappel station should make absolutely sure to review all signals with everyone about to rappel, and it is wise to review them again in any difficult/dangerous spot because people tend to forget.
Audio signals
One set of whistle codes match the word number:
- 1 blast = stop
- 2 blasts = off rope
- 3 blasts = give more rope
- 4 blasts = take up some rope
- 5 blasts = this is monstrous! guided rappel!
A different set of whistle codes match syllables for the most common expressions:
- 1 blast = off/'k/done/yes
- 2 blasts = up rope
- 3 blasts = let down rope
- lots of blasts = stop/no/danger/help/attention/don't do that
The American Canyoneering Academy recommended signals involve both long and short blasts [1]:
- 1 long blast = stop/attention
- 2 long blasts = off rope
- 3 long blasts = help/emergency
- 2 short blasts = up rope
- 3 short blasts = lower rope
Visual signals
It is also important to agree on a standard for hand signals and clarify whether you will use the point negative or the point positive convention. A confusion in this matter can cause people to land straight onto underwater rocks instead of avoiding them.
- Point negative: point where you should not land (eg. point to an underwater rock)[1]
- Point positive: point where you should land (eg. point to the deepest point in the pool)
Managing the station
It is vital to manage each rappel station. Most people can hold their breath for just a minute. Thus, any problem in swift water that is not solved within 60 seconds will likely end in a fatality.
Contingency Anchors
Any potentially dangerous rappel in swift water must be set up with a contingency anchor (a block that can be quickly converted to lowering system), and in general, it is not a bad idea to set up all the rappels with the same technique. The Figure 8 block is easy to learn, quick to set up, and will solve a number of potentially dangerous situations. The person managing the station should also have a knife handy to solve potential extreme cases, such as a canyoner entangled with the rope in a hydraulic. In cases where it is vital to be able to release rope, the block can be rigged in lowering mode and used as such for the first person down. This way, the station manager will be ready to release rope immediately upon signal with no possible complications. In such cases, it is safe practice to install the loose rope (bag side) in the descender of the station manager and lock it. By doing so, the person managing the station will be able to release rope quickly without running risks of becoming distracted and accidentally letting go of the rope.
Set rope length
Becoming entangled in the rope in swift water at the bottom of a rappel can be very dangerous. The station manager and the first person down are jointly responsible for setting the rope length so that the end of the rope is at least a foot or two above the water. By doing so, canyoners will not have to disconnect from the rope at the end of the rappel; they will simply land in the water and be able to swim out without risk of entanglement. If the bottom of the rappel is not visible, it is better to set up a contingency anchor and intentionally set the rope length too short. The first person down should signal the station manager to lower more rope when needed, and the station manager should release the rope until the first person down communicates that the proper length (a foot or two above water) has been reached.
Creep the rope
In cases where sharp edges are present, it is recommended to creep the rope. This is done by releasing the rope very slowly (about an inch every 3 seconds) while canyoners are rappelling on it. This technique will distribute any possible abrasions across a length of rope instead of producing a localized core shot. Packs may also be placed between the rope and the edge to protect against specific edges, but creeping the rope is preferred because it has the advantage of protecting the rope from all detected and undetected edges. Keep in mind that creeping the rope will inevitably lower its end, so adjust the initial rope length setting accordingly using the pitch length as a guide.
Ready to Raise
In some swift water cases where a quick raise may be useful, such as the pothole trap in Arethusa in higher flow, the team should be familiar with at least 3:1 / 5:1 systems and signals to quickly indicate the need for a raise. Those should be ideally pre-rigged/ready to deploy before a person commits to the risk, as rescue may only be effective within minutes.
First person down
This is usually the most experienced canyoner in the rope team. The first person down:
- is responsible for identifying any potentially dangerous swift water conditions and for finding a safe route that will fit the skill level of the rest of the group (which may not always be the most fun route down).
- is responsible for setting the proper rope length by requesting from the station manager more rope or less rope so that the end stands just a foot or two above the water, in order to save the group from the risks of water disconnects.
- must be capable of dealing with improperly deployed rope, entanglements, twists, knots and other incidents that may prevent a smooth rappel.
- must be able to stop and go slow or fast as needed. Thus, it is not recommended to use a top belay, nor is it recommended to simply lower the canyoner down the pitch.
- may choose to slide off the end of the rope before reaching the bottom of the rappel to avoid getting trapped in a hydraulic. Thus, a knot at the end of the rope is not recommended for wet rappels.
- should be prepared to ascend the rope after missing a rebelay/redirection or when conditions are too dangerous.
- is responsible, after getting off rappel and overcoming any possible danger, to assess the hazards and set up a safe jump, slide, or guided rappel for the rest of the group.
Last person down
The last person down is usually the second most experienced canyoner in the rope team and usually, but not always, the same one that managed the station. The last person down must be able to face the swift water dangers like everyone else, but with the added complexities of a rope bag hanging from the side of the harness (to deploy the pull down rope) and with no one at the top to help if something goes wrong. The rope bag can be very dangerous in swift water, and it should be tossed down at first sign of possible swift water danger. When positioned at knee level, swift water may overflow the rope bag and tangle the rope around the canyoner, causing them to become stuck. If landing in a hydraulic, the bag can act as a sail and drag the canyoner down, regardless of the extra flotation they are wearing. If tossing the bag, toss it to a location where the team below will be able to recover it and get it out of the way. With the pull down rope out of the way, the rappelling conditions of the last person down will be similar to that of those who preceded.
Risk of a stuck rope
If pulling the rope down with the block attached is problematic because of the risk of it becoming stuck (eg. jammed in a crack), the last person down should take the block out and choose one of the following options:
- Double strand rappel: In this case, it is good practice to clip a tethered carabiner into one rope strand just above the descender; in this manner, the strands of rope will untwist as the canyoner rappels. Untwisting the strands will facilitate the pull down, especially on long pitches. Rappelling double strand can also be useful to protect the rope from sharp edges since theoretically only half of the total force will be applied to each strand. Assuming the rope has been installed correctly on the descender, the canyoner can creep the rope by locking one strand (by grasping it with the non-rappelling hand or by looping it around a horn on the descender) while simultaneously allowing the other strand to slide through the descender.
- Single strand rappel using bottom anchor: If rappelling double strand is too risky for the last person down (eg. there's a hydraulic at the bottom), the last person down should remove the block and rappel single strand using a bottom anchor. For this purpose, the pack with the pull line is either tossed down to the others or handed over to the second to last person, who will rappel half way down and then toss it to the team below. Once the team has the pull line, they will attach it to a suitably strong anchor, or even set up a human (aka meat) anchor. This will provide a bottom anchor for the last person down, and the canyoner will then be able to rappel single strand, leaving no block on the rope. It is advisable to utilize a contingency block on the bottom anchor to provide extra safety for the last person down, or in order to creep the rope to protect it from sharp edges.
Knots in the rope
When a bend is used to join a rappel rope with a pull line (eg. Flat Overhand Bend), it may still be possible for the last person down to rappel double strand by placing their descender below the knot. If a potential risk exists of the knot becoming jammed in a crack or making the pull difficult, it is wise to grasp and lock the rappel strand with the knot (as described above) in order to force the knot to travel along with the rappelling canyoner until it has cleared any potential jamming risks. Prior to using this technique, make sure there is enough extra rope on the other strand to account for the shift in length. Make sure that both strands reach the bottom of the pitch (or just above the water).
References
- ↑ 1.0 1.1 Carlson, Rich. "Canyoneering Signals". American Canyoneering Academy. Retrieved 21 April 2016.