River Diving: Technique

by

Larry “Harris" Taylor, Ph.D.

 This is an electronic reprint and expansion of a portion of a three part series on river diving that appeared in SOURCES (May/June 1990, p. 33-34). This article is made available as a service to the diving community by the author. This article may be distributed for any non-commercial or Not-For-Profit use.  

All rights reserved.

  Swift water river diving can be extremely hazardous. Although knowledge from reading may assist the diver’s understanding of the environment in which the diver has chosen to play, there is no substitute for proper training. River diving is a specialty that demands techniques and equipment beyond most recreational training.   

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River diving can place exceptional physical demands on the diver. Thus, river divers should be in good, if not superb, physical condition.  Crawling around a river bottom will require upper body strength. Divers should pace themselves and be cognizant of the stamina of the smallest person of the buddy team. Moving against the current can be fatiguing and can rapidly deplete air supply. Divers may inadvertently place themselves in a position requiring heavy workloads. Excellent cardiovascular conditioning and a reserve exercise tolerance is a requirement for swift water diving.

Divers should have a separated-diver plan. This is not a major problem while drift diving with both divers on a line connected to a float. However, in some intense current situations, towing a float is both unsafe and impractical. Where we most often play, there is an erosion barrier break-wall along the entire length of the river; the current is 2-10 knots and boat and fishing traffic is heavy; a direct ascent to the surface is not a desirable option. Also, in that current, a diver above the river bottom, especially on the surface, will rapidly increase the separation distance between buddies. Under those circumstances we have adopted the following plan: Before the dive, one diver is named the "designated mover," the other diver is the "designated non-mover."  When separated, both divers look around and then move to the wall along shore. Upon reaching the wall, the "non-mover" remains stationary for three minutes and then surfaces along the break-wall..  On the surface, the "non-mover" holds position along the wall by placing the river stick into the corrugated steel structure and notes the location.  The "mover" (usually the most experienced river diver) goes to the wall and moves upstream for two minutes and then downstream for one minute and then surfaces.  Once surfacing, the divers wait 10 minutes and then, if no contact is established, call for rescue assistance. Since the divers have surfaced along the wall, the last known point can be reasonably established, if a search is necessary. Note that the above plan is not universal. It is used by experienced river divers diving near shore in intense current with a restrictive barrier along the shore.  Under these circumstances such a plan has been useful.

 

Mover/Non-Mover Strategy Needs Fixed Barrier to be Effective

“Stick and Glide”  

The essence of all diving is to move in harmony with the environment. In all confrontations between Mother Nature and humans, the human will lose. Thus, the secret to successful river diving is to "go with the flow" and to do so with control. The cardinal rule of river diving is "keep your fins lower than your ass."  When moving in intense current near the bottom of the river, move with legs spread (like a "spider") and drag your fins along the bottom.  (Remember fins should NOT have large openings, as these holes are potential places for objects on the river bottom to impale the diver's fins. This has resulted in the loss of diver's fins and has the potential worst-case scenario of pinning the diver on the bottom.)  If your fins get higher than your buttocks, then you are more likely to lose control and tumble. If you find you legs rising, kick hard and drive downward at a slight angle.  Once velocity is established raise the head and allow the legs to get below your buttocks. The preferred orientation is moving headfirst or sideways down the river. By moving sideways, the silt from your dragging fins will not cloud your visibility. Moving sideways allows two divers to stay together by moving down stream facing each other. In some areas, particularly in a clay bottom, the visibility can deteriorate rapidly. If that occurs, stop, and allow the silt to move downstream. Once the clay cloud has moved past the divers, downstream progress can be resumed.  

The real key to control in the river, however, is the use of the "river stick." This device is used to help pull the diver upstream, to hold position to recover those valuable river bottom finds and to control velocity during the drift downstream. The basic technique is to called  "stick and glide."  The force of the current will keep the diver moving downstream, the "stick" acts as a brake to control velocity and orientation. The stick is used almost continually. The idea is not to stop, unless something is spotted that the diver wishes to pick-up, but to move down the river with control. Typically, a buddy team faces each other and moves downstream perpendicular to current flow. The “river stick” is continually moved ahead of the diver and impaled into the bottom. As the diver drifts by, the stick is lifted and replaced. The hand not containing the “stick” moves along the bottom to help hold position.  This “stick-glide-recover-re-stick” cycle is repeated as the divers move downstream.  This allows buddy contact to be maintained in low visibility water.  So, if one diver finds something worth recovering, the stick, impaled into the bottom holds position. Since the divers face each other, when one diver stops, the other diver is aware of the halt and either waits or assists recovery. (A common separation point is when one diver stops to recover an object and the other buddy, unaware, continues drifting beyond visibility range. Facing each other allows both divers to recover objects without fear of separation.)  With practice divers can move at will along the bottom (as long as the river bottom allows the 6" spike to penetrate.) 

 

"Stick & Glide" - Stick holds orientation and controls downstream speed

Freehand stabilizes position and moves ahead of diver

 

 

The “stick” also allows a diver, with physical exertion, to move upstream. This is done by extending the “stick” ahead of the diver to either hook an object,   (large rock, tree branch, or debris), on the bottom or, if the bottom allows, drive the stick into the bottom.  This "reach-and-pull" can also be used with a technique we call the "inchworm." This involves anchoring the "river stick" and then lifting the back into an arched position. The current moving over the arched back assists in holding the diver on the river bottom. Once an arched position is achieved, then the arm holding the "stick" is extended and the cycle is repeated. This successive reach and collapse (like the movement of an inchworm) is physically demanding and used primarily only for short excursions in moderate current. In some cases, it is possible to use this technique without a "stick."

 

 

 

The "inchworm" technique

 

 

The “Creeper”    

A device known as the “creeper”  facilitates moving upstream. The "creeper"  is typically home made from ½’ steel bar stock (See river diving equipment for specifications ). Basically, the creeper is a three-legged device; with the back leg a central anchor point. The diver alternatively pivots on each of the forward legs and moves it forward to a new anchor point. The diver thus “zigzags” a course upstream. Using a "creeper" can be strenuous, especially when significant distances must be covered. To assist the diver, we have done the following: a large ( 3 inch) snap shackle on a short (18 inch) line is attached to the chest harness of the diver. The other end of this short line has an eye-splice loop. A non-locking carabineer connects the short line to a 4" steel ring that is attached to the "creeper" (see photo of the creeper  in river diving equipment). When the diver is tired, the diver can release the hand grip and allow the line between harness and creeper to hold position without physical exertion. Once rested, the diver can once again grab the creeper and move forward. The large snap shackle allows the diver easy access to the connection should the diver need to release from the "creeper."  The large ring also serves as an anchor point for a dive flag (so surface support can monitor progress/position), a "y-yoke" for two divers using the "creeper" in search mode, and as a place to secure a line for raising and lowering the "creeper" between the water and the surface support platform.

 

Using the "creeper"

The "creeper" can be a convenient anchor point/search platform for probing or excavating the bottom of swift water areas. For this application, the "creeper" is secured to the bottom and one or two divers work behind the creeper.  The diving flag is secured to a large steel ring on the "creeper" using a non-locking carabineer. This allows the creeper, rather than the divers, to bear the burden of holding the flag  in place against a strong current. In addition, the flag gives surface support staff a method of documenting position searched by the divers. The divers can use the same "y" yoke used in drift diving (See river diving equipment for specifications). In this case, the "Y" yoke (see below) is hooked to the ring on the "creeper." This allows divers to stay together and communicate (via rope tugs), even in extremely low visibility.  One advantage to working in current is the rapidly moving water clears the area of debris as it is lifted out of the hole being dug

    Creeper used as a stationery anchor for search operations

We have used the "creeper" in either single or 2-diver per device mode. In a single diver mode, during excavations, the diver works in the immediate vicinity of the creeper. In a search mode (see below), the diver, using the "creeper" as an anchor, can run repetitive, increasing distance pendulum arcs away from the creeper 

 

 

With two divers per "creeper", both divers, each on a different side of the stationary "creeper" can work on excavation. In search mode. a line can be deployed directly behind the creeper. Our double buddy line ("Y-yoke," see Equipment  ) is secured to the search line and then both divers can run a search pattern parallel to the baseline.

"Flying"

One special thrill of intense (> 4 knot) current diving is to "fly" 6-10 feet off the bottom and let the current hurl you downstream. As long as visibility gives the diver enough time to avoid objects, this can be an exceptionally challenging and invigorating activity. This activity is only for divers with sufficient swift water experience to be comfortable in such intense current.

Conclusion

River diving, like all specialty environments, has its own set of requirements with respect to diving equipment and techniques. The unforgiving nature of extreme current flow has cost many divers their lives. This is one specialty area that most definitely requires techniques and equipment different from typical open water recreational training.

This is one portion of series of articles on river diving. Others are

Reading Rivers

River Diving: Navigating In Currents

River Diving: Equipment

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Photo Credits:

Surface Photography: Larry "Harris" Taylor

Diver Underwater: Mike Spears

Sketch Artwork by Maureen Reilly

    About The Author: 

Larry "Harris" Taylor, Ph.D. is a biochemist and Diving Safety Coordinator at the University of Michigan. He has authored more than 100 scuba related articles. His personal dive library (See Alert Diver, Mar/Apr, 1997, p. 54) is considered one of the best recreational sources of in North America.

  Copyright 2001-2007 by Larry "Harris" Taylor

All rights reserved.

Use of these articles for personal or organizational profit is specifically denied.

These articles may be used for not-for-profit diving education.