Minor Outbursts

Day 299: Like most Pacific Northwesterners, when temperatures start edging into the upper 80s and lower 90s, our glacial streams and rivers get a little cranky. Tahoma Creek has a notoriously short temper in this regard, and over the last several days, made its displeasure with the weather known in a set of at least two minor outbursts. When Joe and I drove over the bridge on Wednesday en route to a Team Biota survey, it remained muddy and high despite having had close to 24 hours to calm after its most recent tantrum. It had gone down another two feet by the time we returned to take photos, and new deposits of mud and rock were visible in its bed. It was still pounding hard on the buttresses at either end of the bridge, a reminder that once not too long ago in a major fit of anger, it joined with the larger Nisqually to destroy Sunshine Point Campground. Outburst floods like these two most recent surges may have a number of different initiating factors, including pooled glacial meltwater being released when an ice dam collapses. Tahoma Creek has experienced several outbursts of this nature.

All In A Day'sWork

Day 251: On the way to work this morning, Kevin and I came in through the Nisqually gate as usual, passed Westside Road with a casual visual survey to see if any more "memorial" flowers had been placed in a certain spot, but then as we passed over Tahoma Creek, we both did a double-take at the appearance of brilliant colours in the creek below. From the passenger side of the car, my first thought was that it was the jacket of someone who had tumbled into the raging waters. Kevin, in the driver's seat, saw that it was a bouquet of balloons. We pulled over immediately and descended to the creek where I selected a stick of sufficient length to serve as my rod, and successfully landed the trophy in a matter of a few minutes. How the balloons got there is anyone's guess, and why they stayed stuck at that particular spot is an even greater mystery. A ranger's job may be many things, but it's never boring.

Photo credits go to Kevin who captured the landing of the big fish with his cell phone.

Tahoma Creek

Day 305: And now for the official release concerning yesterday's event, with two views of the creek taken from the main Park road on my way home tonight. As you can see, it is still quite muddy and turbulent. In the upstream view, you can see new deposition of silt on the left side of the image.

Glacial Outburst Flood and Debris Flow Occurs at Mount Rainier National Park

Westside Road Temporarily Closed Through the Weekend

A glacial outburst flood and debris flow occurred at Tahoma Creek in Mount Rainier National Park on Thursday, August 13, 2015 beginning at approximately 9:40 am. The glacial outburst flood originated from the South Tahoma Glacier as a 0.5 acre portion of the terminus of the glacier broke off and quickly released water stored in the glacier.

The outburst flood event was first reported by a park volunteer who was working near Tahoma Creek on an unrelated research project. The volunteer heard a loud roaring sound, followed by the sounds of water moving boulders and the cracks of breaking trees. As the debris flow from the initial outburst crossed the Westside Road, the volunteer hiked to higher ground. Another volunteer at Indian Henry’s Hunting Ground also heard the loud roar coming from the direction of the South Tahoma Glacier and hiked to a safe location near the suspension bridge over Tahoma Creek to report on subsequent outburst surges.

The debris flows was also recorded by seismic monitoring equipment at Emerald Ridge in Mount Rainier National Park at 9:40 am, 10:30 am, 11:30 am and 12:40 pm. The largest event was recorded at 11:30 am and generated a debris flow that reached the Westside Road at approximately 12:00 p.m.

Mount Rainier Park rangers and geologists responded quickly contacting park visitors in the area and assisting them across the area impacted by the debris flow. A Hughes MD530 helicopter from Northwest Helicopters assisted the park with two reconnaissance flights to look for park visitors hiking in the area, check the condition of the trail for possible washouts, and check the South Tahoma Glacier for possible additional outburst geologic hazards. All of the park visitors in the area were accounted for by Thursday evening, but park staff will continue to monitor visitor use in the area.

Some damage to Mount Rainier’s Westside Road was reported on Thursday. The Westside Road will be closed at least through the weekend as the park continues to monitor Tahoma Creek and assess damage to the road and area trails.

“This most recent glacial outburst and debris flow demonstrates again that Mount Rainier is a dynamic landscape,” said Randy King, Mount Rainier Superintendent. “Visitors should be aware of their surroundings when traveling in the park. Remember to remain alert for changes in water levels, unusual sounds or shaking of the ground. If you are near a river or stream, move quickly to higher ground.”

About seven waves of debris flow occurred on Thursday afternoon and evening. As the outburst flood moved down valley, it carried sediment, rocks, and uprooted trees and deposited the debris within the Tahoma Creek valley near Mount Wow in Mount Rainier National Park. A stream gage on the Nisqually River at National registered the 0.5 foot river rise on Thursday afternoon. The debris flow had no impact to properties outside of Mount Rainier National Park.

A glacial outburst flood is a large, abrupt release of water from a glacier. The exact mechanisms through which water moves through glaciers and how these events occur are not well known. Geologists report that stagnant and slow moving ice on the lower part of the glacier combined with faster moving ice on the upper glacier, have been associated with these events in the past.

Since 1985, over 30 debris flows have occurred in the Tahoma Creek valley. Glacial outburst floods from the South Tahoma Glacier during hot, dry weather caused most of the debris flows, but heavy rainstorms in the fall caused several others.

Tahoma Creek Suspension Bridge

Makeup Day 7: The Tahoma Creek suspension bridge often stops hikers in their tracks for a few minutes (sometimes longer) until they can come to grips with the fact that they're not going to get from Over Here to Over There without crossing it. It is one of two "build-your-own-bridge" kits in the Park, the other spanning Carbon River in the northwest corner. Both are substantial (pun intended) improvements on the former wood-and-wire contraptions, but nevertheless, I have seen a range of people from little old ladies to strong men go down on their knees to edge across either on more than one occasion. The braver individuals still tend to grip the wire handrails tightly, and set a nervous, hesitating pace which causes the structure to bounce more radically than it does when taken at a normal stride. I'm a veteran. I hold my trekking poles vertically in one hand so they won't catch a cable and run the other hand lightly along the top wire as I stride across. About mid-way, I do a catch-step to break the oscillation as it transfers to the descending portion of the planking. And then, if I happen to have a companion, I stand at the far end and offer words of encouragement, which is to say I berate them for being one of the world's biggest chickens, bruk-bruk-bruk.

These kit structures are so solidly built that they do not need to be let down on one side during the winter to ease the weight of snow build-up. Not so the old bridges! I remember coming upon this particular crossing in late October or early November one year with my sights set on Indian Henrys, only to find that the right-side cables had been relaxed and the planks were hanging at a 45-degree angle over the canyon. I was not in a mood to be denied the remainder of my hike, so by holding onto the cables still tautly strung and placing my feet carefully on the top ends of the planks, I worked my way across, the weight of my pack causing me to tip backwards even farther than the angle of the boards. I didn't know about Donkey then, or I'd have said, "I'm lookin' down, Shrek! I'm lookin' down!" Still, I did the deed (alone, mind you, with no one to tell me how foolish it was), and of course had to repeat the adventure on the return to the trailhead. Given this history, I hope my readers won't fault me for making fun of those who this newer, sturdy, substantial bridge intimidates. After all, I'm still here to tell the tale.

Seasonal Greetings

Day 84: Merry Christmas, everyone! This photo was taken on my Christmas Eve Day walk up Mount Rainier National Park's Westside Road and shows snow-covered Mt. Ararat, so named because early explorers purportedly found wooden timbers on its summit. Ararat is to the southwest of Indian Henrys Hunting Ground which in summer is one of the Mountain's most beautiful wildflower meadows. The trail to Indian Henrys from this side was badly damaged during a flood some years ago and was never reconstructed. It is currently listed as an "unmaintained" trail, and the washed-out sections often present navigational challenges, particularly if Tahoma Creek is running high.

Tahoma Creek Suspension Bridge

Day 258: A couple of days ago, our SCA intern Joshua mentioned that he was thinking about taking a hike up to Tahoma Creek Suspension Bridge and it occurred to me that I hadn't been up there since the last big flood. The trail is no longer maintained and in fact is not readily noticeable unless you know where to look for it along the West Side Road. My late husband and I considered it one of our favorite short hikes and many times, we'd go on to Indian Henrys if time permitted, but during the winter of 1998-99, huge sections of the trail collapsed into the creek channel, leading to it being closed to the general public. It still saw considerable use, often as a bail-out point for Wonderland Trail hikers who felt they couldn't go the whole route, and the repeated foot traffic established detours around the worst sections. Some small improvements were made by trail crews, but use was still discouraged. A second flooding episode in 2006-07 did further damage, and that was what I had not seen for myself until today.

The river cuts quite close to the embankment early on. There is a hazard from dirt/rockslides for a short way, and then the route becomes rather indistinct once it enters the river channel. I found it much easier to follow back in afternoon sun than I did going up with the morning light in my eyes. Once this section has been conquered, a series of relatively minor but aggravating ups and downs go from channel to forest and back again, with frequent clambering up root or rock "stairs" only to find you must go down again on the other side. You mustn't be afraid to get your feet wet, either. Some of the side-stream crossings were a bit wide for my stride.

There had been so much alteration to the landscape that I really didn't recognize much until I came to one enormous rock outcrop about a quarter mile from the bridge. "Oh, I know you!" I said, and then promptly found a small waterfall, another old friend. As I passed the trail sign near the bridge, I felt a twinge of nostalgia, remembering how after leaving our camp at Devil's Dream, my husband and I had cooked breakfast at that very spot during the Wonderland Trail trip we made together in 1978. Bruce was always terrified of the bridge, and I couldn't help but wonder what he would have thought as I sprinted out into mid-span for the photo without ever touching a hand-rail.