Upper Level Stream Crossings, updated

A post Philip put up the other day temporarily boosted traffic to this post from 2013, prompting me to give it a re-read.  One of the best things about this website is being able to delve into the past and get a little taste of what my life was like then.  In this case, coming off an excellent and intense Bob Open course.  It’s also nice to read my old words and agree almost entirely with both what I said and how I chose to say it.  I’m bumping that old post for those who may not have been around back then (the comments are illustrative), reposting a revised and amended version below.  It has been a big snow year across much of the American West, and those venturing out in the Northern Rockies or Sierras this spring and summer will likely have to deal with stream crossings a bit above their comfort level.  My thoughts on the subject might help some.

R0020217Minor stream crossing, Bob Open 2016.  A bit over knee deep for 2-3 steps, but fast, very cold, and slick.  Technique wise and especially mentally this sort of crossing is right where many folks start feeling challenged, and where the conventional wisdom comes up short.

Upper level stream crossings can mean two different, but not mutually exclusive things: moving water crossings higher than the knee of the person walking, and crossings far from the assistance of others. Discussed below are several levels of analysis one should bring to such things.

The more I think about the subject of difficult river crossings, the more I chat with and see how people cope with such things in the Bob Open and elsewhere, and the more I read articles like the one mentioned above, the more I am convinced that the mental distinction is more important than the physical one.  I’ve often felt scared contemplating a river crossing, but I’ve never come close to falling while doing one, which I think reflects both the importance of minding ones fear as well as the extent to which that fear won’t (and in wilderness shouldn’t) push us too close to our limits.  Philip says that he doesn’t do stream crossings much more than knee deep, which is a reasonable distinction to draw for ones self, especially in slick and cobble-y New England.  The conventional wisdom on stream crossings, which he sums up well, is made for that kind of approach.

I do not think the conventional wisdom makes much sense for tougher crossings when solo or in a small group.  Frankly, few people have much if any experience with the stuff I discuss below, which would be fine if (unlike the commentor/spammer in the original post) they recognized that and held their tongue.  Just because someone (myself included) claims to know something doesn’t mean they aren’t full of crap.  Judge for yourself.

IMG_1330Swift, cobbled, and flooded.  I swam the lake upstream.

Preparation and assessment is important. It may not be realistic to have a list of all potentially problematic crossings and their solutions, but in the age of satellite photos there is little reason to not do your best.

Volume is the first and most obvious factor. In the lower 48 there is a good chance that some river or creek in the drainage basin has a gauge on it. Find out how close to flood that stream is often running at the time of year you plan to be there.

The drainage basin is the second factor. How big is the basin, what percentage of the aforementioned river volume does it constitute? Insofar as many problem crossings have to do with snow melt, what is the altitude and aspect of this basin? South facing stuff will melt out faster under solar influence, and so forth. Different altitudes melt out at different times. Estimate how much water might be coming down a particular drainage.  Correlating melt with flows become more problematic the further one gets from the snow in question.  Desert river, for example, react very differently than mountain streams.  The largest body of past data is your best hope, even if it doesn’t give much certitude.

Gradient has a massive influence on difficulty, as folks the other weekend found out.  All other things being equal, steeper is harder, both because the water will be faster and because the channel will probably be narrower and thus harder to move up and down.

Vegetation can have an influence on crossing difficulty, insofar as burnt trees can end up in larger drainages and provide bridges.  Not a good thing to count on, for reasons to be addressed.

Geology is perhaps the more important factor, perhaps moreso than volume and drainage (if only because that datas use will depend on previous on the ground experience).  The surface under your foot will make an enormous difference in strategy.  A fast, waist deep crossing with a uniform gravel bottom is pretty easy.  The same on basketball to microwave granite cobbles is terrifying.

Find this stuff out before you go.  Sat photos will even allow for site-specific scouting in many cases.  If the photos are recent that awesome log jam might even still be there.  If you don’t think you’re ready to confront the ambiguities which might come up, don’t go.

IMG_6492Slick cobbles and opaque water are a bad combination.

Once you’ve done your homework and selected a route with crossings that are in theory doable, it is time to put things into practice on the ground.

I’m not a big fan of the conventional wisdom which says to keep your pack loose and unbuckled.  It is true that a big pack (>1/5 body weight) will make it tough to get up if you go down in fast water.  It is also true that unless you’ve done some serious training, such a pack will make a hard crossing much harder simply by virtue of added weight.  Having it loose and floppy will only make this worse.  I’ve also never been especially clear what you’re supposed to do if you shuck your pack in a crossing.  Look for it downstream?  Keep essentials in your pockets and have a long, hungry walk out?  Better to keep a light pack, keep your pack on and well cinched, and if you must carry a big pack (hunting, field research) factor that into trip planning.  You might need to take a different route, or go at a different time of year, or bring more people and/or different gear.

Any upper level crossing requires special preparations before you get wet.  Putting on shell clothing and perhaps a warm hat or vest won’t keep you from feeling the cold water, but it will blunt the shock and save some body heat and function should the crossing take longer than you think, or if you go under.  Removing socks and clothing makes no sense unless conditions are quite warm.  Everything which needs to should be sealed in waterproof bags in your pack, and the pack should be compressed tight.  You want the pack to be as low profile as possible should the water come past your crotch, and you want the pack to absorb as little water weight as possible.  You should trap some air in your dry bags and/or pack liner, but not too much. Some buoyancy in the pack will help in particularly deep water, but too much will make it harder to keep your head up if you have to swim.  Ideally, some practice beforehand will help you tune this.   Lastly, it’s a good idea to have some essentials in waterproof storage in your person.  Firestarters, headlamp, map, and a few snacks.  Whatever you’d need for self-extraction should you have to discard your pack.

It hardly needs to be said that crossing specific shoes like sandals and crocs are not appropriate.  You want the best traction possible for difficult conditions, so just get your shoes wet.  One pole is a good idea, provided it is stiff enough to take body weight.  Two poles are harder to control.  Remove larger pole baskets, as they cause problematic drag.  Clothing, especially pants, should be trim for the same reasons.  Even when soaked WPB boats and heavier pants don’t add that much weight, and won’t pull you down like an anchor.  If there is any chance you might swim, added flotation is a necessity.  A basic snorkeling vest takes up little space, can be worn with a pack, and provides an adjustable amount of flotation in the correct location to keep you head up should you swim.  If it provides enough peace of mind to allow you to perform near your best, it is a worthy addition.

Crossing strategy will be determined by the environmental factors mentioned above, in combination with your own mental and physical abilities.  Scouting for a location can take some time under difficult circumstances.  In the lower 48, most trail fords have been wisely placed, as the requirements of pack trains and hikers are much the same.  It’s worth reading Andrew and Jon’s Open reports for their accounts (and Jon’s photo) of crossing Lodgepole Creek.  As can be seen from the map, Lodgepole doesn’t have too much gradient.  It does have a big basin, and small slick cobbles on the bottom.  Greg Gressel crossed at the lowest spot right above the river, which is steeper and a bit shallower.  Greg lost his feet on that one.  I crossed at the main trail crossing, which is longer but gave me a longer window of recovery before being swept into the Middle Fork.  Andrew, Chris and Jon crossed on a log not far below the upper trail, and bushwacked a good ways back to the lower trail to get on route.  Their thought process, that the upper crossing might be gentler, was a good one.  Lodgepole was just blown out with a lot of melt coming out of its big, south facing basin.  There was no truly easy crossing option.

I crossed Lodgepole facing upstream, with a single stiff trekking pole lengthened to around 135cm.  I had both hands and a lot of body weight on the pole.  The last 1/4 was the deepest and fastest.  For the first 3/4 I angled upstream, while for the last 1/4 I let the current take each step a little backwards.  I put my foam PFD on for this crossing.

I prefer to make upper level crossings facing downstream whenever possible.  Fighting the current by facing upstream takes a lot of energy and is slower, prolonging exposure to cold and further sapping physical and mental energy.  However, foot entrapment is a huge safety concern during high crossings, and for this reason I face upstream and strive for deliberate foot placements when dealing with cobbled and boulder-bottomed streams.  If you loose the upstream fight against the current, pivot quickly and face downstream, tap dancing frantically to keep toes clear of crevices.  For most crossings in the Bob and Glacier this is my favored method.

For crossings with graveled, sandy, or muddy bottoms, a strong diagonal facing downstream is a my preferred method.  A stronger current will increase the ratio of downward to sideways travel.  Lean upstream into the current and drive your heels in, propelling yourself sideways and allowing the current to force you downstream.  Below crotch level this technique is pretty trivial.  Once your pack and butt are underwater the force of the current will speed up the process quite a bit, and by the time your ribs get wet you’ll likely be in intermittent contact with the floor.  This is fine, maintain directional velocity and go with the flow.  If/when you loose your feet for a while, lean into a backstroke and enjoy the flotation provided by your pack.

This technique works well for rivers and streams with muddy bottoms and quicksand, as your never putting too much pressure on any foot, and can lean back into the current for leverage when pulling a foot free.  I’ve used the downstream diagonal technique with good results often, and in many places.  Both Thorofare and Mountain Creeks, in Yellowstone during this trip, yielded to carefully finding the clearest way across the inevitable deep channel, then doing a quick and deliberate downstream stride/shuffle/glide across.  The surprisingly deep crossings of the Escalante during this trip succumbed to the same technique, and speed was important because on those chilly short days managing cold exposure was a serious safety issue.

Scouting a good crossing is vital.  Shallower water, good bottom conditions, and most especially plenty of clear water downstream.  Sweepers, strainers, and rapids should be well avoided.  Whatever your margin for error, double it.  For waterways where silt impedes visibility, caution is warranted and effective difficulty level goes up considerably.

IMG_1160Tapeats Creek, Grand Canyon.  On this October trip not deep, but swift and in places the only option between rock walls.  My mother was nervous, so we gave her plenty of support during the extended downstream wading sections.

The most difficult crossings will be those which do not offer good options.   One example was 25 Mile Creek during the Bob Open back in 2013.  As the map shows, 25 Mile is steep.  It is cobbled.  The drainage isn’t huge, but much of it does face south.  Greg Gressel crossed a bit above the trail, climbing through a steep section split into three braids.  None of those crossings would have been more than 8 feet wide, but the rocks were bigger and the swim uglier if you lost your feet.  Cyrus and Kate inflated boats and rafted around the creek on the Middle Fork, a safe option I seriously considered.  Andrew, Chris, and Jon took the path I outlined on the map; bushwacking up to a flatter spot where they crossed with little difficulty.  The volume of 25 Mile was probably only 2/3 that of Lodgepole discussed above, and thus not too bad when given a reasonable gradient.  I crossed at the trail, facing upstream and taking an upstream diagonal.  The strongest current was at the far side, and my upstream path gave me the furthest margin of error should I have lost my feet at that point.  A swim through the steep riffles below would have been bruising, and a good place to snag a foot.

I’m not a big fan of log crossings.  They have to be really good to be safe, and often tempt you into high consequence, all or nothing situations.

Group crossings can make a big difference, especially for shorter and lighter group members.  Communication and coordination difficulties make many traditional ideas better in theory than application.  The two stack for upstream facing works well, with one person behind the other holding on to shoulder straps, but it can be hard for the second person to see their feet.  Downstream crossings with the weak person leading, and the person behind creating and eddy, weighting their pack, and verbally and physically guiding them are also effective.

R0000283Packing a tahr out down a small but very steep creek in New Zealand.  Cliffs demanded a couple crossings each mile, and often the choice was between wading an 8 foot wide, waist deep pool or climbing across slick a boulder waterfall.  I got my crotch wet a lot.

In the field, calculation and restraint must come first.  Better to hike out than hurt yourself.  At the same time, indecision and timidity will only cause problems.  Once you decide you can do a crossing, do so boldly and with full commitment.  As with most things, safety is primarily created by the mind, and a strong mind comes from experience and practice.

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2 Responses to Upper Level Stream Crossings, updated

  1. I came across this a few weeks back. May or may not be interesting, but you get to decide.

    “The New Zealand disease… In Colonial times drowning was referred to as the New Zealand disease because so many people died trying to cross rivers etc. It is hardly surprising given the number of beaches, lakes, rivers and streams in this country.”

    From “Tramping Skills: River crossing” https://nzbushadventures.blogspot.com/2017/03/tramping-skills-river-crossing.html

    • DaveC says:

      A darn good post, thanks for that. Their advice and swimming and on using one big stick for crossing support is better demonstrated than what I said.

      Having been there since I wrote the original post, it is now easy to understand just how hazardous NZ rivers are. Limestone cobbles seem to be the rule rather than the exception, and there are few places in the US where rivers rise and fall quite as rapidly.

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