Wet Sandstone

Last weekend, I got bitched out for climbing on sandstone 36 hours after a rain storm. I have heard that climbing on wet sandstone is not a good idea because the rock is weaker. So my questions are:

1. Is wet sandstone weaker than dry? If so, explain why.
2. If this is somehow true, how long is appropriate to wait for wet rock to dry?

Yes wet sandstone is weaker than dry sandstone.

Sandstone is very poreus(sp?) think of a sponge....when it's dry it hard and doesn't bend easily. But when its wet...
It also depends on the type of sandstone....Eldo doesn't count.

36 hours should be more than enough time.
There are alot of different factors to consider....how long and how much did it rain? Is the rock in the sun? Was there wind?
What kind of climb is it? Cracks are not as big of a deal as faces.

Your best bet is to let it dry out a day or so...depending. 36 hours is plenty.

josh

Don't forget that there are different kinds and formations of sandstone. The soft, edgy sandstone in Red Rocks is particularly fragile after rain and you should stay off of it for 2-3 days after a soaker. The Windgate in Indian Creek is equally soft but its lack of handholds may lead to to want to climb it. Resist the urge. The rock is very soft and repeated traffic will accelerate wear in the cracks and on the edges. Go hiking or mountain biking for a few days after the rain there, too. The rock in Eldo is Fountain sandstone but seems to be pretty impervious to the effects of water. I'd be careful (as always) about monkeying around on the creakers but other than that, I think it's okay. Any other observations from Eldo prancers?
Mal

Yes. Find some gneiss or granite in damp conditions.

In SoCal we have sandstone too. Climbing your favorite route when damp can lead to heartbreaking damage.

Malcolm Daly wrote:Any other observations from Eldo prancers? Mal

As solid as any granite I've seen as far as weather is concerned, the Flat Irons and New River Gorge are also examples of bullet proof sandstone. I heard the stone has quartzite mixed in or something that gives it it's solidness. Then you have Garden of the Gods or Red Rocks that is super soft and porous that need a thorough drying before it's safe to take big falls on those 20 year old pitons.

Andrew C wrote: As solid as any granite I've seen as far as weather is concerned, the Flat Irons and New River Gorge are also examples of bullet proof sandstone. I heard the stone has quartzite mixed in or something that gives it it's solidness. Then you have Garden of the Gods or Red Rocks that is super soft and porous that need a thorough drying before it's safe to take big falls on those 20 year old pitons.

I'm not a geologist, but isn't sandstone the source material for quartzite? Just add zillions of tons of pressure and cook at a zillion degrees?

I think of Eldo as half-baked quartzite.

I believe quartzite is a metamorphosed sandstone with a high silica content.

Kenny, the matrix that holds the sand grains together becomes mush when it rains so as long as the moisture content remains high it would be a positive life choice to stay off.

There are a couple of good tests that I use in the local areas (Garden of the Gods) to decide if it's too wet:

If the ground is still moist.
If there are wet spots still on the rock.
If the sand in pockets is still moist.

I'm not a geologist so I don't know if those are foolproof methods but I have yet to rip off any major holds on sandstone climbs. Sometimes you have to dig down a little to see if there's moisture. Also if it rains for a long time or you have really moist days, or snow that sticks around on the rock, you may have to wait longer. Cloudy days or climbs in the shade don't always dry out as fast. I know it can be a pain but it behooves everyone to err on the side of waiting too long otherwise those sandstone climbs will turn to junk.

Hey Kenny- The stuff up at east animas is particularly sensitve to fragility after rain/snow.

That being said, the climbers that frequent that area are even more sensitive to the issue.

yeah, you can tear holds right off the watch crystal if its still moist, and it seems to hold the wetness longer than other kinds of sandstone.

its happened before, so it doesn't surprise me that you were nawed on....

+1 on what Capt. E said. But to add to it this includes all Durango sandstone not just East A. If its wet climb inside if its snowing go ski or ice climb.

Shawn Mitchell wrote: I think of Eldo as half-baked.

Taken out of context just to remind the senator that there are goofs out there.....
Shawn...did you back the Medical Marijauna laws 2?

Cheers my friend!

josh

We have some nice, dry sandstone down here in AZ in Sedona. Saddle up and come down for a nice visit.

Thanks Josh! If someone is going to butcher my quotes into insults, aiming them at locations or inanimate objects is better than unleashing holy hell at puppies or school teachers or something. :)

Nah, I'm doobious (heh) about medical pot. The debate and its advocates feel like a mass movement of anti-prohibitionists to make it pretty much universally legal and accessible. If that's the case, then let's just have that debate and make that decision. Better than creating a bureaucratic exception that spawns a whole "medical" industry based on an institutionalized lie and flaky prescriptions and what not.

Cheers to you too!

EDIT: I think there are some people with real suffering that can benefit from pot. I think their needs could be met by adjusting the regular avenues of medical prescription. But this whole cottage industry/garage supplier thing is just legalization in drag. Let's do it or not.

As a climber it seems some sandstones are weaker after rain. As a geologist I dont know why. Sandstones come in many varieties depending on the sand it's made of. Sand from ground up rocks like volcanics, granites, metamorphics, even limestone and is called lithic arenite. Sandstone composed of well rounded quartz would be quartz arenite, and can be aeolian (from wind, like the Navajo), fluvial (from a river), or marine or mixed (like the Dakota). Quartzite is a pure quartz sandstone with a silica cement (originally the term meant metamorphic). Sandstones are held together with cements, which can be clay, calcite, iron, or silica. Lyons sndstone in the Garden of the Gods is an aeolian/beach sand with clay and iron cements. The Fountain Formation in Eldorado and the Flatirons is arkosic conglomerate with silica and clay cements. Silica cements are very hard, not easily water soluble, and shouldnt weaken after a rain. Sandstones that are much weaker after a rain, like the Dakota or Lyons, seem to have more clay cements so I speculate that the clays (which can take up water in their crystal lattices) are the part that weakens when wet.

I know I'm a bit late on putting in my two cents on the subject of wet sandstone but I just joined Mountain Project and this is an important issue for my home bouldering area.

This winter has been a wet one here in Southern Nevada, good for the desert, bad for the sandstone. Not only have we had lot's of rain this season, but Red Rock Canyon has been covered with snow several times as well, and currently there is still lot's of snow on the north facing aspects of the canyons and the big peaks.

The boulders at Kraft Rocks definitely suffer from this winter's wet weather. It's not often that it snows on Kraft Rocks, but this winter the snow did make it that low at least twice. The sandstone at Kraft Rocks is wet right now, at the moment if you pull off a chunk of rock on some indiscriminate boulder, guaranteed it'll be moist at it's breaking point, even if the piece has patina on it.

Throughout this winter their have been many day's when the boulders have simply been out of condition, so on those day's I hike around Kraft Mountain. Several times on these day's when I thought it best that I not climb on the wet rock, I have encountered people bouldering at Kraft. Throughout my hike I always approach and politely ask individuals to please give the rock some more time to dry out. The "Pearl" is a fine example of a must tick problem and even with snow on top and at the base of the boulder people are trying to send, despite water dripping down it's face! There are some boulders that are okay to climb the day after it rains, such as aretes.

For the most part climbers are fairly receptive when I talk with them about the wet rock. I explain that the sandstone actually does not fully dry out in the winter, especially a wet winter, it appears to be dry on the surface but underneath it's weak. I cringe at the thought of walking up to the Pearl someday and seeing the flake that provides the key edge has been broken off. I don't want that day to happen!

During the summer you can climb as soon as the rock drys out, even after even the most torrential down pour the rock can be dry in an hour. But during the fall, spring, and especially the winter, the rock should be allowed at least a full day to dry out. But when it's been a wet winter, as has already been written, sometimes two to three days is what the rock needs.

I love Kraft Rocks!!!

Andrew Fulton wrote: I don't want that day to happen!

But it is going to. The sooner you come to terms with that the better...

Ah sandstone, it is made of sand, like sands through an hourglass so are the days of our lives...

Malcolm Daly wrote:... Any other observations from Eldo prancers? Mal

From experience I have broken a few Eldo holds over the years when the rock was moist and/or wet. Typically, this rock will have an ever so slight "grainyness" to it. Case in point, I broke off the bottom part of body sized upside down dagger that you use to lay away on a seldom done route up near Rincon. The dagger seemed super solid, but a bit moist and the broken piece was the size of my head.

I went climbing two days after a moderate rain at Cannibal Crag at Red Rocks. We found that the north (shady) side of the boulder was still damp to the tough even after perhaps 45 hours since the rain, so we avoided it. The other side seemed totally dry but I saw some nonessential foot chips break on the lower slab, and was spooked about what would have happened if a hold on one of the cruxes had broken. Lesson: 36 hours is definitely still the red zone for soft desert sandstone. Give it two days at least for rock in the sun, probably three for shady crags.

Kenny Miller wrote:Last weekend, I got bitched out for climbing on sandstone 36 hours after a rain storm. I have heard that climbing on wet sandstone is not a good idea because the rock is weaker. So my questions are: 1. Is wet sandstone weaker than dry? If so, explain why. 2. If this is somehow true, how long is appropriate to wait for wet rock to dry?

36 hours should be good, as for question #1 it's already been answered.
A good way to judge, if the dirt below the boulder is still wet don't climb it.

As a So-Cal sandstone climber I agree with the theory that has been said here a few times now. If the dirt that is underneath the climb is still wet the sandstone is probably still too wet to climb, I too have ruined a great climb.

As for a drying time, I think 36 hours is a minimum and I have seen sandstone that has taken weeks to dry.

So how many inches of direct rain is the immediate "don't climb" threshold for soft sandstone (considering rain as the only variable)? 0.01in, 0.10 in, 0.25 in etc...?

I'm curious what numeric amount you think it would be