Thesis: it is unethical to climb on ANY wet rock

I am being taken to task in another thread for suggesting that it's ok to climb the Flatirons if wet.
mountainproject.com/v/third…

chris schulte wrote:Yeah, while there is very solid stone in the Flatirons, and it is not like Red Rock or Indian Creek, you wanna let All Rock dry out before climbing on it. Water gets behind the flakes and so on. Sure, the Flatirons "Fountain Sandstone (?)" dries Fast.. But don't climb on stuff when it's wet. Or when it's closed. ... Anyhoo... Even granite can break when it's damp.

BDergay is even more emphatic-

BDergay wrote:Sand stone is weaker after getting wet. PERIOD. Now, one can argue that that Boulder's sandstone is a bit more compact and therefore less likely to be impacted. But- there are still PLENTY of holds that are porous. As I mentioned- exposed flakes might have softer rock- smaller edges will be weakened. And for you two to be telling a tourist that sandstone is fine after the rain, and with such proof as "seems impervious to moisture" and "as far as I know" and of course "never worried about a hold breaking and it's been damn wet".. wtf?! I can't believe we're sitting here debating whether sandstone is impacted by moisture.... and, as mentioned, telling someone not familiar with sandstone that it's okay....

This seems ridiculous to me. Am I missing something?

I can see refraining from climbing porous rock if wet. But NOT climbing at all if any kind of rock is wet because something might break?

Then obviously we should't be climbing on dry rock either, because sooner or later something just might break off....

Anyone making the above statement has not climbed on NRG sandstone. If you stopped climbing there after a rain, nobody would ever get any climbing done.

Same at the Red. It's fine to climb in the rain there. I understand there are many places where you must let the rock dry before climbing, but it's stupid to think that all rock, or even all sandstone, is like that.

Have you ever been mixed climbing? You're pulling a much smaller surface area on rock that is more often than not wet at some point throughout the route. The following are all mixed climbs in the Flatirons.

http://www.mountainproject.com/v/call-the-copps/105910774

mountainproject.com/v/east-…

mountainproject.com/v/east-…

mountainproject.com/v/fourt…

Geologic time includes now, rocks will fall down.

Can attest to this. Red River Gorge sandstone becomes sort of slimy and slippery after rain/heavy humidity, but from the week I was there (it rained almost everyday), I never once felt like any hold was about to snap off because of the dampness. Everything seemed pretty solid.

Now Wingate, Navajo, etc. That sandstone definitely needs time to dry out.

Honestly. If I plan a weekend to go climbing and I haven't been climbing for a month and the next trip isn't for another three weeks and it is wet, guess what, I'm going climbing.

Wild Iris limestone is bomber during a downpour.

Rained all day everyday on a trip once and we weren't going home without pulling on some stone.

We climbed in our rain gear.

Until the lighting came.

haha you can climb on basalt all day long, no matter how wet...

Sorry Guys but I have to agree. If there is even the slightest chance that the rock may be wet you should stay home. I think that is great information to share.

ECTradClimber wrote:Sorry Guys but I have to agree. If there is even the slightest chance that the rock may be wet you should stay home. I think that is great information to share.

Even granite? Limestone? Do you have any evidence that water weakens the rock? Please share your insights.

JCM, thanks for the explanation. What about the flatirons?

matt c. wrote:JCM, thanks for the explanation. What about the flatirons?

The Flatirons and Eldo are a unique case, as they are not just sandstone. They are metamorphic sandstone that was reheated and changed in form. That's why it's so super hard compared to Garden of the Gods, which is the same formation but lacking the heating. You get another outcropping of the hard stuff at the old South Table Mountain climbing area off 115 that is now closed. So you need not worry about water getting into the rock on the Flatirons or Eldo. It's no longer able to.

Now the red choss Fountain sandstone at Red Rocks OS and Garden of the Gods will soak up rain like a sponge and ooze out water for days afterwards.

Gunks quartzite is Fine. May be slippery but it adds a bit to the adventure. That rock is bomber.

Enoch M. wrote:Gunks quartzite is Fine. May be slippery but it adds a bit to the adventure. That rock is bomber.

Pretty much all rock is fine with the exception of softer sandstones. Even limestone is fine after rain, as the variety we like to climb is not that porous. Of course weak carbonic acid in ground water will slowly eat the limestone, but it takes a very long time for that to happen and it's only at the surface.

The problem with sandstones is the binding cement that joins the grains is what gets weak with the addition of water.

I think further south at garden of the gods the fountain is calcite cemented, making it much weaker.

matt c. wrote: Even granite? Limestone? Do you have any evidence that water weakens the rock? Please share your insights.

There is significant evidence that water weakens rock. . . it's called erosion. There proof in science. IF there is even a 10% chance in rain don't go climbing outside. Especially if your at my local crag.

ECTradClimber wrote: There is significant evidence that water weakens rock. . . it's called erosion. There proof in science. IF there is even a 10% chance in rain don't go climbing outside. Especially if your at my local crag.

Wind also causes erosion. Therefore don't climb on windy days, because SCIENCE. genius.

matt c. wrote: Even granite? Limestone? Do you have any evidence that water weakens the rock? Please share your insights.

Snark meter may need to be recalibrated.

cfuttner wrote: Wind also causes erosion. Therefore don't climb on windy days, because SCIENCE. genius.

Oh yeah, that's true too! Don't go climbing on windy days also. Definitely stay home or go to the gym.

Okay... First off, if we're going to debate something then reading comprehension should count.

Now everybody referencing NRG or Kentucky sandstone go re-read the original poster's first sentence. Here's the relevant part:

"for suggesting that it's ok to climb the Flatirons if wet."

I know some sandstone in the desert where you could shatter giant flakes with your pinky finger.. but like east coast sandstone, that desert rock is irrelevant towards the discussion of Boulder sandstone.

Okay.. now, in regards to COLORADO sandstone, moisture weakens it. PERIOD. How much it's weakened depends on the quality of the sandstone. As I said in the original tread ( mountainproject.com/v/third… ) Boulder sandstone is very strong. So some moisture *probably* doesn't hurt it too much. But on small flakes, delicate edges, one might want to exercise some caution. Anyone want to disagree with this assessment?

Now the problem in the original tread came about when a tourist/visitor, while inquiring about climbing in the flatirons, was told by Mark E. Dixon to not worry about all the rain we've been having, that, "The rock seems impervious to moisture, so no need to let it dry out" this was seconded by John Tex.

My issue was that one shouldn't go telling someone, not familiar with area sandstone, to disregard warnings about climbing on wet sandstone.
Once again, does anyone disagree with that assessment??

Now, regarding Schulte's remark that even granite is impacted by moisture. That surprised me too. But- when it comes to knowing about the relative strength of various rocks in various conditions: I'm more than willing to defer to Schulte on that matter till proven otherwise.

Now, to summarize so there's no mistake about my position:

1. Moisture weakens Colorado sandstone, but the degree to which depends on the quality of the rock in question.
2. You should, if you're not going to refrain from climbing on wet sandstone, at least be a bit more careful.
3. Don't tell Colorado tourists that wet sandstone doesn't matter.

I’d be interested to see if there is actual research out on this. My guess would be no but seems like an interesting project - testing the strength of different types of sandstone while wet vs dry. I’m sure the results would vary greatly by formation. In addition, I would bet that there are several types of sandstone that do not become weaker in the time frame we are talking about - hours/days.

I have climbed on sandstone at red rocks, red river gorge, Arkansas, southern Illinois, Moab, and Colorado. I also have a masters in geology and have worked as a geologist for 7 years. In my experience, the flatirons are among the most impermeable of all the sandstones I have been on. That doesn’t mean it doesn’t get weaker but it does mean that I’m not sure if some rain water would make it weaker during the time it takes to dry. And while I agree that mineralogy of the sandstone cement plays a large role as JCM has outlined, I think permeability plays an equal role. Many types of sandstone are highly permeable (red rocks, etc) and rain water will infiltrate the rocks matrix porosity (primary porosity) within minutes and make the rock easier to break. However, there are plenty of rocks (hard granite) that are so impermeable that they essentially have no matrix porosity and liquid would only permeate through these rocks at large time scales aka geologic time and through fractures/faults/vugs (secondary porosity). But its also important to state that a crack in the rock (fracture/fault) is not matrix porosity. Liquid in a crack is not necessarily inside the primary porosity of the rock. It is only for sure inside a break in the rock and may only be on the rocks surface. This does not necessarily take away from the point that a fracture/joint might become weaker (although Im not sure it would have any affect in an impermeable rock) but it could mean that within impermeable sandstone, a face hold or anywhere on the rock without a conduit for water does not become weaker in the short time frame of raining/drying.

I’m not fully advocating climbing after it rains. I’m just thinking about the science of it and in my experience, the earth is nearly infinitely heterogeneous so I’m sure there are sandstone formations that are greatly affected by rain, others where it doesn’t matter at all, and all sorts of in between.