by CAMERON McPHERSON SMITH
copyright 1996
BIVOUACS
The idea of the bivouac (or bivvy) is simple enough; it gets dark, you find a ledge, cave or whatever, lay out your gear and get some sleep. If you've planned the bivouac in advance, this might be enjoyable and a rewarding end to a day of hard work; it is also possible that the bivouac can ne the most horrific of experiences, and many climbers avoid them like the plague... Consider the route; can you reasonably imagine finishing it without a bivouac ? Would it be best to bring a bivvy-bag, just to be safe, or would you trade that extra pound of weight for swiftness ? It's up to you and your partner and the conditions. The Sleeping System
The sleeping system you choose to take on a c limb will depend on the nature of the climb, the weather and the amount of time you plan to spend on the climb. The basic piece of gear is the sleeping bag. The type of bag you buy, and it's 'warmth' should be based on your own experience; some people a re going to be cold in even the most mammoth bags. Others will be warm in a lighter bag. Your personal physiology is the critical factor here. Think back to camping tips or climbs in the past and try to assess how 'warm' you sleep. Sleeping Bags, Bivvy-Bags and Vapor-Barrier Liners
The main choice in sleeping bags is between synthetic and down for insulation. Down has a warmer weight-to-warmth ratio than any other sleeping-bag insulator, though some synthetics are closing the gap these d ays. Down also compacts better than most synthetic bags, taking up less room in your small alpine pack. This is something to consider carefully, as is the weight of your bag. If dry, down is an excellent lightweight insulator. If wet, however, down is virtually useless. The main consideration when climbing with a down bag is to keep it dry. Some manufacturers make down bags with a waterproof-breathable shell so that the chances of them getting wet from the outside (e.g. rain, wet snow, a spilled mug of tea) are reduced. Research your choice carefully and pick something which balances light weight with warmth and durability. Most of the time you use a sleeping-bay, you will also use a bivvy bag, a large, theoretically waterproof-breathabl e overbag into which your sleeping bag slides. This is fair enough, but down can also get wet from inside if you crawl into the bag with damp clothes, or simply sweat a lot at night. This can be manageable for a short climb, but over a period of a week or more, the down can get increasingly damp and start to lost its' properties of insulation. On many alpine climbs you'll be unable to change clothes and will indeed get into the bag while wearing damp or wet long-johns, unless you go naked (which may be preferable, though the long-johns may not dry out as well hanging on a line). To keep the down from getting wet from the inside, some climbers use a vapor barrier liner (or VBL). Essentially, this is a thin nylon envelope the size of your bag which you put inside the bag as a liner. You crawl into this and your sweat stays inside it, rather than dampening the down. If I could give you advice on this, I would, but it seems to be individual preference; some find the VBL to be clammy and unco mfortable. In my experience, it is worth the slight discomfort; it's better than getting your bag wet. The VBL adds only a few ounces to your sleeping system, but also can prevent real problems and will normally increases the 'warmth' of you bag by abou t 10oF. In sum, the best way to prevent your down bag from getting wet is to shield the down from both outer and inner sources of moisture; a VBL inside and a bivvy-bag outside is the most secure system. If you get a synthetic bag, k eep it dry as well. A bivvy-bag will be the best shield here, but a VBL is overkill with synthetic bags. Some salespeople may suggest that you can reduce the size of a stuffed synthetic bag with a compression sack. I find this an unnecessary extra piec e of 'techno-hype'. If you really need to save that much room in an alpine backpack (and you might - remember this when buying), think about a down bag, or stuff the synthetic bag with maniacal zeal. When you stuff your sleeping bag, you ma y be able to save some room in your pack by putting extra socks or gloves or whatever down into the 'core' of your bag. Just don't go overboard, and don't put anything sharp inside. If the stuff-sack of your sleeping bag is not waterproof, and your pack is riddled with holes or otherwise liable to let in water, consider putting the stuffed bag into very thin, almost weightless plastic bag. This may save your from much misery. Better yet, see the suggestion below on stuffing your sleeping bag and bivvy bag at the same time. More on Bivouac Bags
In selecting a bivvy-bag keep in mind the weight and the room it will take up in you pack (though it's often possible to stuff a bivvy-bag into a sack smaller than the one it comes supplied with; i f you do this, be careful not to damage your bivvy-bag by puncturing it with it's own zipper-pulls). Your main choice in bivvy-bags will be between those which are completely constructed of a waterproof-breathable and those with a waterproof-breathable u pper and a coated nylon 'bathtub' floor. See Figure XX. The coated-nylon models are usually a little heavier, but are also usually substantially cheaper. Also, if you're using a ground mat (see below), you'll generally be shielded by it from any real w etness. It is useful to buy a 'long-model' bivvy bag so that you can put your boot liners, camera, gloves and wet clothes inside to keep them warm and dry. If you buy a bag which is not seam-sealed with tape, you're defeating the purpose; rain will get in through the stitching and you'll get wet. Finally, get a bivvy bag with a simple and efficient entry-slot and breathing hole. Try the bag out in the store. I suggest you buy a long, seam-taped half-nylon bivvy-bag. Though this will be heavier than other bivvy bags (though cheaper, probably), it is a basic piece of equipment that you should not skimp on. Whatever type of bag you buy, you might be tempted to stow the bivvy-bag and the sleeping bag separately in your pack. This may be accept able if you're not too concerned with volume. If you're fighting for room in your pack, though, or are expecting really nasty conditions, it's a good idea to put the bivvy bag over your sleeping bag before you stuff the sleeping bag in it's sack. This c an save room in your pack (stuff hard !) and, if you unpack the system in a downpour (you will someday), it keeps your bag dry until you slip inside. Insulating Mat
The insulating mat is a critical component of the sleeping system. This is a mat used somewhat like a mattress, though it's primary function is insulation, not comfort. The sleeping mat puts a barrier between you and the cold snow, ice or rock you're sleeping on. Believe it or not, the variety of insulating mats on th e market has also ballooned to demented proportions. There are ridged mats, inflatable mats, self-inflating mats and everything in-between. Luckily, the choice here is simple and obvious. In CLIMBING #110 (October 1988) Jonathan Waterman tested an unbe lievable range of 27 different sleeping insulator systems. In short, he found that the most effective insulator was a stack of two Blue-Lite thermal pads. As far as alpine-weight pads go (say, less than 18oz), second to this came the Thermarest Ultralig ht, an inflatable mat weighing 16oz. I consider this too heavy and bulky for all but the coldest alpine climbs. I strongly suggest a single, regular-length Blue-Lite pad. This weighs only 8oz and insulates you for an 'increase in comfort' of c.11oF. T he longer specimen can go down past your shins, but you can just rest your feet on your rope or backpack to solve this problem. For colder climbs (and I mean really cold, as in Alaska), take along two Blue-Lite pads. You can stow the insulation mat rolled up and across the top of your pack, but this tends to get in the way and snag on ropes and slings. I suggest rolling it as tightly as possible, securing it with a couple of hefty rubber-bands (or tied loops of inner-tube rubber) and then strap ping it to the center of your pack. This keeps it out of the way and can provide a shock-absorber in a fall (hey, you can always hope !). The inner-tube rings can be operated with frozen fingers much more readily than any strap or buckle, and are more r eliable than velcro, especially if you're squeezing up a chimney. If you're interested in reducing weight, consider taking just a 1-foot square piece of insulating mat that you can sit on in an emergency, and use your pack and rope to insulate t he rest of your body from the snow. In summary, then, the sleeping system should keep you insulated from the ground and keep you and your sleeping bag warm and dry. Whatever system you devise, make sure it fulfills these requirements. Bivo uac Sites
Before you can settle in for your forty winks you need to take some precautions in selecting a bivvy spot and making it safe. These are detailed below. Bivouac Site Safety and Rigging
The first thing you must consider in selecting a bivouac spot is safety. It's no good settling on a nice big ledge only to get hit by rockfall or an avalanche while a safer but less comfortable spot may be elsewhere. Keep moving until you find a bivvy spot sheltered from whatever objective dangers exist. Keep in mind features of the mountain which are above you but are not visible in the dark. When you find a bivvy site, consider the integrity of the entire site - is it just a giant rock flake which may come completely off the face, or is it perhaps a blob of snow which looks nice until you notice that it's a cornice hanging out over space... Find a place where you can get some good anchors in, and tie in as soon as you can. Except on the largest ledges, you should stay tied in at all times, even in your sleeping-bag. You may find it useful to set up a 'handrail' rope which you can hang your equipment on or grab if needed. Be sure that the anchors are secure against 'wide-angle' loads, and that if one anchor goes, your gear do esn't slide off the rope and into the blackness below. This can be done by making a loop of the 'handrail' and backing it up with a solid backup anchor rigged for a downward load. The principles are shown in Fig. XX. Remember that the very cr est of a ridge may be exposed to tremendous winds; it's better to take shelter a bit down the flank if you can. On a buttress, keep an eye out for chimneys which may be large enough to accommodate you - but beware these features if storm is approaching a s they can turn into a river of ice water - or perhaps snow - very quickly ending your rest. Two solutions to the possibility of your tumbling off your perch (or incurring frostbite in sensitive areas) while just out answering the call of na ture; first, stay tied to the anchors. Second, wait till light so you can see what you're doing or - better yet - use a piss-bottle (any old plastic bottle or bag will do) and don't even go outside. Bivouac Site Modification and Construction
If a ledge is large enough, just lay out your sleeping system and try to get some Z's. Stay tied in to the anchors. Wear your harness inside your sleeping bag and just thread your anchor rope from your harness up through the breathing hole. If it is raining, water will 'wick' 'down the rope and soak you at the crotch! Try to prevent this by tying a couple of knots in the rope (to retard the wicking) between yourself and the anchors. Also, try to arrange the rope so that it drops down to a point lower than you before it enters the breathing hole...this way, it will be harder for water to wick up the rope to you. These are important points -- don't get soaked this way! If you're on a snow ledge, you may need to make some modifications. If you have a shovel, great. If not, you can use a helmet with great effect, clearing away huge volumes of snow. You can also pack snow into hollows if you need to; remember that the snow will p robably compact quite hard under your weight, and that a small lump will soon become the horn of the Devil himself, gouging your back all night if you don't smooth it out first. If the ledge is of ice, you're in for a big cutting job. Try to find a natu ral ice feature to lessen your work. Use your adze and hammer to hack out a ledge. Any time you work on a bivvy-site, consider paring your clothes down to the minimum while working. Cutting ledges is often warm, sweaty work and you don't want to soak y our clothes. If you find a cave, remember the possibility of lightning danger. Figure XX illustrates this point, and Appendix A outlines general lightning dangers. If you can't find ledge you may be able to cut an ice or snow cave from the surface. Stay tied in to some anchors while you do this. Snow caves take some energy to build, but can be very warm indeed once the door is blocked or the stove is going. Remember that if you use a stove inside a shelter (tent, snow cave, whatever ) you must make a vent to prevent yourself from being poisoned by fumes. If you have a shovel, you've got a real advantage for shaping a site. If you don't a helmet may be used in softer snow, supplemented with your axes. On lower-angled slop es with plenty of snow, you can cut straight in so that your fit side-by-side with your partner. Where there is less snow you may have to tunnel sideways so you fit head-to-toe. Try to make the roof high enough so that you can at least sit up. Trying t o cook and eat and get dressed lying flat on your back is tiring and can be dangerously clumsy. The entrance to the hole can be packed with snow if the wind is coming in, or you can use a backpack to block the wind. Keep the shovel or other digging inst ruments inside the cave; if you're trapped inside by heavy snowfall or avalanche, you'll at least have a chance to dig out. Also, poke an axe shaft up through the roof to make a breathing hole, then shove the axe up and out the roof, and leave it in posi tion. If you're buried, you may be able to pull this out, leaving a breathing hole while your dig out. Figure XX illustrates a number of important points in snow-hole construction and design. You will, of course, have to modify everything as the condit ions dictate. If you're on an ice face and have to have a shelter, the best idea is probably to keep going until you can find something better. Hacking a cave or even a ledge out of hard ice is extremely tiring; you'll probably do less work clim bing up, rapping down to, or traversing across to some feature which will serve. If you have to hack an ice ledge, take turns and stay tied in while chopping. Better yet, predict these problems and bivouac as soon as you get to the last ledge you can se e within the day's climbing. Hanging, Sitting and Standing Bivouacs
On really technical, steep rock routes you may need to set up a hanging bivouac with a porta-ledge or hammock. Consider carrying a lightweight hammock and fly (or bivvy-b ag) on these climbs. If you have to bivvy on a blank alpine wall without a port-ledge or hammock, you're in for an epic. If you're in slings you run the risk of cutting off circulation to your limbs. Improvise some sort of seat from your backpack, or a padded rope; just make sure the blood can flow; this is especially in alpine conditions, where it will be bitterly cold. Some improvised hanging bivouac supports are illustrated in Figure XX. You may some day be forced to pass a night sitting o n a little perch, or even standing. This should really only happen if you can't fix a rope from your high point so that you can rap down to some feature below, and jumar up in the morning, or if you can't push on to something better above or to the side. You may want to sleep (if it's possible) in shifts so that one of the pair can't fall asleep unexpectedly and load the anchors. If you've got any food, have a bite to eat once in a while (fatty foods will keep you a bit warmer), and perhaps brew up som e drinks or just hot water to keep your core temperature up. You can still get in your sleeping bag, even on a standing bivvy, but be careful and stay tied to the anchors. Of course, in all of these situations, keep in mind and apply the BER T system to your anchors. Get moving at first light; you'll be warmer moving than standing still. Tents
Some alpine climbs are long enough - and have big enough ledges - to warrant bringing a tent. This is some, not all; the majority of a lpine routes climbed (again, the routes done on weekends) are done without a tent. In most cases, you can get up and down the route with less weight in your pack and less hassles at bivvy-time if you don't bother with a tent. Still, many alpinis ts own tents because they serve as good 'base-camps' while waiting for a route to 'come into condition' and as a nice shelter to return to after the climb and before the drive home. Though I've spent some days waiting for a route with just a bivvy bag, i t's pretty miserable and not worth the savings in weight on the approach trail. As usual, when you survey the range of tents on the market today, beware the 'techno-hype'. Balance the technology with functional requirements. In my opinion, the most elegant solution has been the Black Diamond Megamid, a simple square fly with a single support pole; the edges are secured, the pole is raised to the desired height and the shelter is complete. There is no floor, but a floor is just one more thing t o damage, is more weight and you'll be in you sleeping system 90% of the time anyway, protected from the snow. The Megamid design is lighter and more compact than any other alpine tent, and it costs less. It is probably not as waterproof as the waterpro of-breathable designs, but, again, in your sleeping system you should stay dry. The Megamid, properly rigged, is also extremely aerodynamic, shedding wind while other tents shudder around their poles. The waterproof-breathable tents are extremely expens ive and I believe they are really most suited for super-alpine work; the Himalaya or other such 'world-class' ranges. If you don't like the Megamid and want a tent, though, consider any of the two-person models which are seam-sealed, easy to set up and t ake down and are most wind-resistant. If it rains a lot where you plan to climb, keep in mind waterproofness, but watch out for the waterproof-breathable designs which you may think will keep the deluge out; I have seen these fail when the air temperatur e hovers around 30oF and freezing rain and sleet are coming down, leaving the occupants bedraggled, miserable and cursing their (admittedly very pretty) $600 'shelter'. No doubt, in extremely cold and dry conditions, these are great, but for most of your climbing, I'd say they are an unnecessary expense. Buy a good, small, simple and robust tent, and use your savings to buy ice screws. A final note on bivouac equipment. If you take it, chances are you will climb with the equipment in the back of your mind, thinking, 'well, I've got bivvy gear, so we don't need to go so fast...". In other words, if you take it, you'll use it. I suggest resisting the temptation. Find out how much you can climb without a bivouac; how long can you go and keep y our wits ? Remember, the longer you stay on the mountain, the greater the possibility for problems. It seems, at first, insane to say that you should spend as little time climbing as possible, but with the numerous objective dangers of alpine climbing, t his is what it boils down to. If you want to bivvy, of course, do it and relish the experience, then weight the experience against trying to climb the route without a bivouac. Choose for yourself.
TABLE OF CONTENTS
Cameron's Climbing Page | Cameron's Home Page