Are nuts and cams less safe if the rock is wet?

Mountaineers doing technical alpine routes certainly use rock pro under wet or icy conditions. However, the kind of routes they're climbing are typically not the kind of high-angle stuff that you have in mind when you go out for a day of rock climbing. There are people who do things like mixed rock/ice climbing, but you really have to know what you're doing. I've never done any aid climbing, but aid climbing in the rain sounds to me like a really, really bad idea, because often the placements are extremely marginal.

I think there are really two separate issues you want to keep in mind when attempting to apply your trad technique under wet conditions.

One is that lubrication reduces friction, so for example a cam in a flaring crack might not hold if it's wet, even though it would have held under dry conditions. But of course not all gear placements depend on friction. If you place a big hex in a constriction, no friction is required. And even with an active placement that requires friction, the way active gear works is based on the principle that as you increase the tension on the rope, the gear presses against the rock harder and harder, giving more friction.

The other issue is rock quality. Even on well known trad routes, there is sometimes rock fall. A rock can hold over and over again under whatever strain is applied to it by climbers -- which could mean placing gear behind it, or simply using it as a hold -- but one day, it comes loose. For example, there could be a refrigerator-sized boulder sitting on huge, sloping ledge at the top of a single-pitch climb, which everyone has been using as a belay anchor. It's been holding non-leader falls for years just fine. But on a day when it's raining hard, that amount of force might finally cause it to slide off.

Erosion is a natural process that shows bursts of activity at irregular time intervals due to conditions. If you're in the mountains during or soon after a storm, you will often see new rockslides. This is why, for example, there are huge debris-control dams at the bottoms of the canyons in our mountains in Los Angeles. Entire towns have been wiped out by boulders and mud during once-in-a-century storms. In other words, there is no guarantee that something will stay stable just because it's been stable for x years in the past.

You're describing temperatures hovering around freezing. One of the natural processes that leads to erosion is the situation where water, ice, or snow gets into cracks between rocks and then undergoes freeze-thaw cycles, expanding and contracting with each cycle. People quarrying rocks have sometimes used this effect intentionally to break rocks apart, e.g., by drilling holes in the rock and letting rain fill them.

The Trad Climber's Bible by John Long and Peter Croft has a brief section on climbing in the rain. They basically describe it as a misfortune that befalls you because the weather forecast was wrong, and they suggest common-sense ways of dealing with the emergency: don't panic; close your chalk bag and stick it under your clothing; slow down and be deliberate about your movements; place more gear than you normally would; pull on gear if necessary; avoid moss and slime.

posted over 7 years ago

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Ben Crowell‭

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The short answer to that is yes - but the real answer is it depends.

If you are climbing on sandstone, this could actually be very dangerous & unethical. The issue with sandstone is that it tends to be a fairly porous rock. After heavy rains, it is likely to have absorbed some quantity of water in those pores. This weakens the rock, compared to the very same rock with empty pores. Depending on conditions (ambient humidity levels and rock itself), it may take some time before it is safe to climb again. The issues about climbing on wet (porous) sandstone is that it is much more likely to break off if you fall on your pro (not necessarily a huge chunk falling down, but you only need the surface to chip out to take out your cam/nuts...) and also that you could break holds. That's bad for safety AND for climbing ethics.

Red rocks (near Las Vegas) recommend 24 hours after rain before climbing - I've heard people talking about 36 hours there to be safe too: Las Vegas Climbing Council

However, Red River Gorge (Kentucky) is also largely sandstone though of a much stronger type. I've been climbing often there while it rained, mostly in the roofy areas where the rocks tends to stay dry, although it will begin to seep in the cracks if it rains enough. I also climbed there in the spring - with all the snow melting, even if the surface of the rock is dry, the cracks are often seeping so it is safe to assume there's moisture in the rock. It's mostly sport climbing though, but the point about the rock being liable to break is just as valid. Bolted routes at Red Rocks are just as discouraged after rains as trad climbs.

If you do a long route, and get caught in the rain, you may then have to climb on wet rock anyways. Of course there's a difference between taking a risk because elements force you to and walking to the crag voluntarily to take that same risk (wet rock). But to show it is not an absolute no-go, depending on rocks.

The main thing is that wet rock will bite less into your placements than dry one, generally speaking. So each placement should be considered with more caution - raise your standards as to what you will consider a good one. Chokes will tend to be less affected than cams because the friction doesn't matter as much - but be aware that it is more likely it will move after you go so be extra careful for this (perhaps equalize more than you otherwise would have).

Regarding freezing, I am aware of nothing that would make much of a difference between say 20 Celsius wet rock a 2C rock. If you mean below freezing, then I would point out that mix climbing (rock & ice) do use both ice screws & rock protections for their ascents (though these guys are crazy, IMO). One of the issue that I see with this however is that it may be more difficult to determine is the rock is fractured (because it may not ring as hollow if ice fills the cracks).

Regarding manufacturer's inputs:

Metollius seems to think so:

Metollius about wet/icy rocks

My opinion on this however (regarding manufacturer's input) is that they are all likely to say it is riskier just because of liability. They are unlikely to provide useful guidelines as to how much riskier or when it is safe regardless. E.g. to me the fact that they describe it as riskier doesn't mean it's a no-go - all things being equal, trad climbing is riskier than top-rope....

posted over 7 years ago

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Francky_V‭

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