Using a Throw Bag

Different sizes and styles of throw bags

The throw bag is one of the most versatile pieces of equipment that a paddler can carry. You can use it as a throw rope to belay a swimmer out of a rapid, as a static line or in a Z-drag to pull a boat out of a pin, as a rope to tow or raise/lower your boat up/down a steep drop during a portage, or to set up your dining fly or clothes line in camp. The bag that you choose depends on what you plan to do with it. 

Length of rope – for throwing, the length of the rope should be determined by the length that you can accurately throw. 50' is generally the minimum for a throw bag. 100' is better for setting up a pull, but may be too heavy and bulky to throw accurately. 75' is a happy medium

Setting safety below a drop

Diameter of rope – once again, the diameter of the rope will be influenced by its use.1/4" rope is light and easy to throw. 3/8" is stronger for pulls, but heavier to throw. 5/16" is a happy medium.

Type of rope – the rope should be colorful for visibility and float on the water to prevent snags and make it easy for the swimmer to grab. The material is usually Poly, Spectra or a combination of the two. Poly rope is soft, flexible and easy to grab and hold on to. Spectra rope is a high strength, low stretch and stronger for pulling. Some higher end bags have a Spectra core for strength and a Poly wrap for comfort.

Bag – the bag itself is usually nylon, sometimes with a mesh section to facilitate drying. The bag should be colorful for visibility, with a large opening at the top to deploy and stuff easily, and durable enough for years of use. The bag will have a foam disk at the bottom for floatation, and a loop at both ends to attach a carabiner.

Additional paddler stabilizes the thrower

The "clean line principle" means designing a throw bag that is free of large loops and attachments that could snag on obstacles or people during a rescue. Following clean line principals makes the bag safer for throws, but less useful for pulls. If you have the room, it might be better to carry a smaller clean line bag for throwing, and a larger bag or rope for pulls.

Rescuing a swimmer with a throw bag takes practice. First you have to find the best place to perform the rescue. This should be downstream of the rapid with a clear place to stand, an unobstructed view for the throw, and a safe place for the swimmer to land.

Pin kit for a Z-drag

Before throwing get the swimmers attention by yelling “ROPE”. The throw can be underhand, overhand or side arm depending on the conditions. The throw should be when the swimmer is in front, and should timed to slightly lead the swimmer so the rope lands on their chest.

The swimmer will position the rope on the shoulder opposite the side that they are getting belayed into. Never wrap your hands around the rope. The swimmer also needs to be careful not to get wrapped up in the rope - especially around the legs.

Once the swimmer is on the rope, the thrower assumes the belaying position with the rope around their back and their feet wide for stability. For extra leverage, the thrower can sit down, or have other paddler hold on to the back of their PFD. In a dynamic belay, the thrower moves downstream to reduce the stress on the thrower and the swimmer until they reach easier water.

Attaching lines to the boat

The other principal use of the throw bag is pulling a boat out of a pin or off an obstruction. Like any other rescue skills, it’s essential that you practiced this before you need it. The easiest pull is a straight pull with a static line. The rope is attached to the boat, and everyone pulls. Often this is sufficient to get the boat free.

If more power is needed, you may need to set up a Z-drag, which provides a 3:1 mechanical advantage compared to a straight pull. To set up a Z-drag you will need a pin kit with throw rope, a prusik, two carabiners, two pulleys and a sling. Here is how to set up the pull.

Step 1: Build an anchor by wrapping the sling around a sturdy tree or rock. Clip a carabiner and pulley through the sling.

Straight pull with a static line

Step 2: Secure the bag end of your rope to the boat. Run the tail end through the anchor pulley.

Step 3: Wrap the prusik loop as far back down the rope toward the load as possible. Clip the second carabiner and pulley through the prusik.

Step 4: Run the tail end of the rope through the prusik pulley and back toward the anchor. Pull on the tail end of the rope in the same direction as the main line is pulling on the boat.

Links:
Choosing a throw bag

Using a throw bag

Quick coil a throw rope
Setting up a Z-drag