Monday, October 10, 2011

10-9-11 Ammonoosuc Ravine, Mt. Washington

This past Sunday, 10-9-11, marked the 10th week since I had been in the White Mountains or set foot on a trail there. My debut hike was to have been up Madison and Adams seen here at sunrise Sunday morning, but there were already 120 cars in the trail head parking area at 6 am so I opted for some place quieter and out of the fray. The weather for the entire weekend was exceptional with valley temperatures in the mid to high 70s and very clear skies. Coupled with the three day Columbus Day weekend, the weather was a big draw for hundreds of folks to make their way to the high peaks.

With an early start I hoped to beat the crowds that on a fine day like this were sure to be heading up the Ammonoosuc Ravine Trail (ART) on their way to the summit of Mt. Washington. I only needed enough time to get up a half way where I would begin to bushwhack up into the ravine itself. My goal was to see if there was any prominent damage in the gullies or along the floor of the ravine from the prodigious rain dumped on the White Mountains by the storm associated with Hurricane Irene. The hurricane tracked west of the Whites through central and western Vermont but the Mt. Washington Weather Observatory collected 6.6 inches of precip (rain) on Sunday, August 28th. That's a lot of water.

I won't go on as I usually do about how wonderful it felt to get back on the trail but it was wonderful to be hiking again (and to feel strong and in good shape). Those ten weeks seemed like an awfully long time. As I finally got going there were a few people just ahead of me on the trail but the number would be much larger number by 8 am. I wondered if there would be a solid line of hikers, with only a few feet separating them, from the base to the summit by 10 am.

I was soon passed by these zany young guys from Montreal who were traveling light and fast and with the same intent to stay ahead of the crowds.

At several places on the trail there was evidence of storm damage although not necessarily from the August 28th storm. There were fresh saw cuts in this debris which mean it could have been storm damage or just routine fall trail croo clean up.

At the lower elevation on the trail the river looked unscathed by high water.

A quarter of a mile further up stream there were downed trees criss-crossing the river and some nominal signs of high water as in rock, even some fairly large ones, that may have been moved or flipped over so that they are free from mosses and lichen.

Less than a half mile up hill from the trail head there was this obvious damage. The trail here is close to the river and at about the same elevation (level with the river) which would account for any overflow reaching this spot. There were signs in other places downstream from this spot where the river, during the flood, had made some incursions on the trail that included areas covered by fine sand, like mason's sand, laid out in long stripes where there had not been sand before.

For the most part, though, the trail was as serene and undisturbed as this.

I caught up with these two young men from Mumbai, India by way of New York City who were on their very first hike in the White Mountains.

The higher upstream that I climbed, an towards Ammonoosuc Ravine, the more signs I saw of impact from the high water from the August 28th storm including the "blasting" that occurred here at the confluence of the Ammonoosuc River with a side stream coming down from Mt. Monroe. The two streams must have joined forces here with a magnified force and moved large rocks some of which were swept downstream.

The high volume of water was able to "float" a lot of debris from the avalanche of January, 2010, that was left upstream from this point. As the flood waters lost velocity in certain sections of the river, particularly at lower elevations, it left debris dams like this one also made up of the remnants of the avalanche.

There was just a minor flow on Sunday in this side channel of the Ammonoosuc River but it had obviously funneled a great deal of water during the August 28th storm. Eyewitnesses reported that rivers in and around the White Mountains rose quickly during the height of the storm on August 28th and may have reached 8-10 feet above the normal seasonal flows. (See entry for 8-29-11 "quick follow-up on Hurricane Irene".) It's hard to picture the river here in this photo 10 feet higher and I doubt that there are many eyewitnesses who were out on the trails during the height of that storm (remember that the whole White Mountains National Forest was closed for two days). At any rate, the rivers receded quickly, too.

I bushwhacked up the north side of the river for a mile through this dense and spindly balsam growth. It was not easy going. I hypothesized that along both sides of the river at this elevation, where the sides of the ravine squeeze together and force the river through a V, the vegetation must be damaged periodically by high water.

This was another confluence where the force of the flood water on August 28th became magnified and was able to cut through the river bank here and it also moved a lot of heavy rocks, gravel and sand out of the channels opening up this wide area.

Every 100 yards, or so, I encountered debris dams like the first one mostly consisting of the year-and-a-half-old avalanche debris from 2010. My expectation of the August 28th storm that I think I stated in an earlier entry was that it might "flush" a lot of the nominal debris found in and along a lot of the river and stream beds throughout the White Mountains that accumulated over time and it would get carried far downstream. The debris dams probably represent a small percentage of the material moved by the flood water on August 28th and that got hung up in these places where I found them as the flood water receded.

This is a side channel of the Ammonoosuc only visible if you hike along the north side of the river and it obviously carries water during heavy flows but on Sunday there was barely any water in it. It would have been interesting to see how much volume it was carrying on August 28th.

In the second photo above you can see some Mountain Ash trees that were smooshed by the flood but that are still alive and putting out these lovely red berries which are a favorite of a long list of White Mountain birds.

The bushwhacking became more and more difficult the higher I went. This is a boulder field most likely from a landslide that occurred many years ago. It does provide an illustration of something I've tried to describe a couple of times that's an important feature of the forest that mantels these mountains. If you look at the moss covered rocks in the above photo you'll see holes, dark splotches, that indicate there are openings in the top layer of soil. As you walk across this area your foot often sinks down a foot, or more and that is because the soil is a very thin layer lying on the roots of the trees. In other words the soil and root systems are suspended above the ground a foot, or more. This accounts for the slow growth and spindly trees in some areas along with the standing deadwood which, as Robert Monahan pointed out, dies from thirst because the roots, being suspended, don't get enough water.

At this point I'd hiked into the bottom of the avalanche track. In this photo you can see from the debris covering the rocks that the flood waters on August 28th must have completely submerged these rocks. It's interesting because the flood waters effected some areas and not others along the river channel.

Just 100 yards away this area that had been heavily hit by the avalanche received no damage from the flood and it looks as though the flood water didn't reach here (I presume that it did). Perhaps this is because the river channel is wider and/or deeper here so the flood water didn't rise as high.

It's interesting to see some of the impact that resulted from the avalanche which opened this area dramatically. These post-blossom Purple Asters are first succession plants that have moved into this area to take advantage of the increased sunlight.

Looking up through the trees killed by the avalanche and into the left side of Ammonoosuc Ravine. The summit of Mt. Washington is on the upper right side of the photo. The morning sun is just rising over the ridge on the fight and beginning to dip down into the ravine.

I took a line up the center of the avalanche debris and found his water course carrying a little water and that ascended steeply towards the right gully. In this photo the ravine suddenly became filled with smoke from the Cog railway that ascends Mt. Washington via the ridge to the left. From the smoke and the sound of the train I could tell it was a little after 8 am.

I tried moving out of the stream bed because it was disappearing in the avalanche debris. I was confident it would reappear up higher but moving it this landscape was almost impossible.

This is looking across the floor of the ravine at trees decimated by the avalanche (again, back in January, 2010). The avalanche probably had high water content (it rained for several days before switching to snow so that the avalanche was a dense wet mass) and it certainly had high velocity because it "rode" high up on the ridge opposite and snapped off the trees you see in the photo.

A half mile higher and the amount of dead wood from the avalanche is astounding. Some of the trees were pushed over but are obviously still alive.

Looking downhill the photo shows some of the birch trees that, being supple, were pushed down by the avalanche but are recovering a bit and standing straighter each year. The mountain in the distance is North Twin.

The day was warming up quickly as I climbed. The sun took it's time coming over the crest of the ridge and as I reached my high point it was just touching these trees.

The view down right gully shows that a huge force of water passed down this water course and moved a lot of stones and gravel which in turn scoured the rocks, cleaning the rocks of moss lichens, and washed the gravel as well.

The rocks radiate in an arc here where the water velocity was greatest. There force of the water much have varied by topography, increasing in steeper parts of the channel and where channels narrowed.

At this point the flood waters were moving very fast and carrying boulders and smaller stones with them down the steep gully. You can see the scouring on the rocks where water loosened rocks scraped and bounced down the channel. The raging current created that curious six-foot high wall, in the form of an arc, and, as the water receded, left the stack of woody debris on top of it as a decoration.

This was another place a third of the way up the headwall where the flood water created another wall and the scouring on the larger rocks is also evident. Above this point right gully becomes very steep. There are two magnificent cascades coming down from the top which I had difficulty photographing because the sun was directly in the camera lens. I'd like to return, though, and climb the gully walls with adequate protection in the form of rope, etc. Two summers ago Johanness Griesshammer and Arran Dindorf, both on the Lakes of the Clouds croo in 2010, bushwhacked all the gullies on Mt. Washington including the three prominent ones in Ammonsoosuc Ravine. They might be better able to define the extent of impacts from the August 28th storm based on their earlier explorations.

I bushwhacked down and to the left a bit to get back to the Ammonsoosuc Ravine Trail at Gem Pool. I often get scratched while bushwhacking in this kind of terrain on my forearms and shins and some blood oozes from these superficial cuts. When I pop out onto a trail and meet hikers they're sometimes alarmed by my appearance. Their first thought is that I've been mauled by a bear, or some other large animal.

This is the branch of the Ammonsoosuc that drops down from Lakes of the Clouds via Gem Pool. In fact this photo was taken a 50 feet down stream from the pool. It's difficult to tell if the August 28th storm impacted this part of the river as a lot of the moss on the rocks is still in tact, but there must have been significant increased flow here both in volume and velocity.

The storm did clean out Gem Pool to some extent. It would have been nice if it had taken out those dead falls to the left. I've tried to pull them out of there in the past but they're wedged in.

Gem Pool below the surface.

This is some new work by the trail croo just below Gem Pool and indicates some flood damage to the river bank here. It was always a little sketchy here but possibly water coming down the river bank from above washed away a small section of the trail.

This new bridge was further down the trail and in a perennial wet area.

Near the bottom of the Ammonoosuc Ravine Trail on my way out. The sunlight "had the feel" like it was about noon. With winter approaching the light is changing rapidly.

I reserved this block of photos for the end of this piece in case some readers are not interested in photos of hikers. I took them coming back down from Gem Pool on Sunday only because I was astonished by the sheer number of hikers there was on the trail and the enormous diversity they represented. This photo reminds me of many discussions over the years about crowds in the White Mountains and the fear that some day there will just be long lines from the bottom to the tops of the popular summits. A photo above shows what it could look like. I tried to get the blur in this photo on purpose for effect. I won't comment on the photos as I'm not using them to be judgmental and I hope that you like them. Taking them was certainly enjoyable.



















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