Wednesday, August 4, 2021

I-70 Closed and California Zephyr Cancelled by Mudslides

(Some of the photos have satellite locations)

Stuart Gardner posted twelve photos with the comment: "Glenwood Canyon got hit again yesterday [July 31, 2021] about 2 hours after I left. I just got back into town and I was checking the radar on my phone and there it was, all red all over the canyon. I hiked up a couple of the draws yesterday, and from the flow evidence I estimate we got 1500 to 2000 cubic feet per second peak flows. I would have predicted about 150 cfs hundred year flowrates.  These pictures are from a helicopter flyover this morning. (I did not ride this time) I'll be heading up again tomorrow to see what I can from the ground. I'm glad I didn't waste any money washing my truck from yesterday's trip."
[There are 369 comments. Since the ones presented were basically people tagging other people, I did not dig through the post's comments. Fortunately, there were some meaningful comments on some of the photos.
There was a wildfire last Summer. And it has been raining heavily for days. So they got the double whammy of no vegetation to fight erosion and lots of rain. As Stuart commented above, they got over 10 times the design flood.]
Colter M Hess shared
Gloria Gallegos: When this road was build they had put certain restrictions on how they could build it without them getting in to blasting big boulders or removing any vegetation! It needed to be as natural as possible! They never though of the future problems! Now they can’t find a way to fix it because of the restrictions!

[A comment said that it continues to rain every day. That would explain other comments about concern for the worker's safety.]
Julie Coy: You can see that part of the roadbed itself has bees broken off this time, with rebar exposed. And if you look at the photos of the same section from the side it looks like part of the roadbed had dropped down about a foot. You can’t just drive the dozer over that section of highway and remove the rock and mud like they have been able to do in the past. This is gonna take some major repair.
Edwin Thompson: Julie Coy actually, that is post tension cable. It was laid criss cross then concrete poured over. When the concrete is cured, they pull the cables to 33,000 psi, cap them, cut the rat tale off and seal them in. All of that concrete is now destoyed. A major rebuild taking months will be required. And, that is assuming the mountain stops sliding down so they can. In my opinion they may get just one lane open to 2-way traffic. And a year to fix the other.

Jim Harris: This spot is just west of Grizzly Creek

Michael Wilde: No amount of engineering could offset the amount of debris that is coming/will come down from the burn scar... that culvert was more than adequate when vegetation existed in the drainage above.

Wagon Gulch

[I recognize that as the dam for the Shoshone Hydroelectric Facility. At least in this case the road is an access road and not part of I-70.]

This is the Hanging Lake Tunnel complex. Cinnamon Creek runs over the top of it.

Jacob Shafer: Just wait until next years high water, the highway will be buried.
Joe Farrell: Looks like there is a lot of undermining going on at this point. That water is stripping everything away from the support for the roadway.
Karla Truxell Schritter: After the first huge debris deposit here a couple weeks ago they had heavy equipment in the alluvial fan to create a channel for the water to flow through the center of the riverbed, but continuing storms have washed more rock and mud down the gulch 2 or 3 more times since then, completely undoing that effort.
Mindy Brugman: Karla Truxell Schritter just west of our town a few years ago a big loader was trying to clear debris on the highway and a relatively small debris event came down pushed him off the highway into the nearby lake and he drowned they didn't even pull up the machine as far as I know. It's a very dangerous thing to try to keep these roads cleared and it's very difficult to engineer something to survive such debris torrents and floods. But they do. I like the idea of having some kind of a road sign when there's intense rain falling upstream from an area that the highway is threatened by. And it would just tell people to stop or to not go. I'm not sure if people would listen or we could get the warning there in time but if it's a link to a weather radar we should be able to say how intense the event is. But then of course there could be another event more intense near the radar that's blocking the signal. But there are many ways to check that there's an event going on. I think a forecaster assigned to such things could help more than just automating such warning signs. We do it for avalanches I don't know why we couldn't do it for debris torrents usually just a few hours or a few tens of minutes really.
[There are quite a few comments about the "debris fan" shoving the river up against the highway and eroding the foundation.
Note the rail in the lower-left corner. Since that debris flowed over the tracks, there is probably a railroad outage there. (Later, I saw the tracks were clear here. But UP had problems in other areas.)]

Wagon Gulch - AKA Flamingo Gulch
[There are quite a few comments about the flamingos.]

Stuart Gardner commented on photo 9
I loved those flamingoes.
[They are plastic.]

Steve Slagter: Better perspective on the depth of the fan coming from Devils Hole... that is a bunch of material,
[I can't imagine how the tracks escaped damage here. Some comments indicate the track is covered by rock slides in other areas.]

This is the railroad on the other side of the river from the interstate. You can see the tracks on the right.
Julie Krelovich Snyder: Looks like they are going to stop construction between Gunnison and Montrose so that traffic can go that way, also.


Union Pacific Railroad posted four photos with the comment: "If it’s not fire, it’s floods! A shout out to our crews digging our tracks out from under mudslides in Colorado’s Glenwood Canyon."

Bruce B. Reynolds: The slide fence being demonstrated.



The July 31, 2021 closure reported by Stuart Gardner must have been at least the third I-170 closure this Summer due to mudslides because this second one happened June 27, 2021, between exists 87 and 133.
CDOT via ColoradoSun-0626
"The highway was closed in both directions between the West Rifle and Dotsero exits after muddy debris covered an area in Glenwood Canyon more than 80 feet wide and 5 feet deep, according to the Colorado Department of Transportation."
[CDOT cleaned this one up in 2 days. [ColoradoSun-0628]]

CDOT via ColoradoSun-0626
Mud as deep as 10 feet covered Interstate 70 in Glenwood Canyon on June 26, 2021. The debris flowed during heavy rains over the Grizzly Creek burn scar. (CDOT)
The [weather] service said radar indicated heavy rains over the Grizzly Creek burn area, with as much as 1-inch of rain in an hour.

USGS via ColoradoSun-0626
The U.S. Geological Survey created this landslide hazard map following the Grizzly Creek Fire. The map notes several areas above Interstate 70 near the Grizzly Creek and No Name exits where the likelihood of debris flow following a big rain was 60% to 80%.

It made the news in Florida.
Unacknowledged via FloridaNewsTimes
Glenwood Springs, Colorado-More than 100 people, including nearly 30 people evacuated to tunnels, had to spend the night on the highway after rain caused another landslide in a wildfire-burned area of ​​western Colorado.
[They do close I-70 if flash floods are predicted. They did predict the first storm cell. But they missed the second one.]

This was one one of the mudslides that happened before the late July big ones.

"I-70 West through Glenwood Canyon has been shut down at least eight days since May 1 due to mudslides." [KDVR, Jul 6, 2021] And there has been a lot more closed days since this report.

CDOT via ColoradorSun-0801
Interstate 70 through Glenwood Canyon will remain closed for the foreseeable future after Colorado Department of Transportation employees surveyed damage from recent mud and rock slides and found damage “unlike anything they had seen before.”

Screenshot, Aug 02, 2021
[They received twice the normal amount of rain for July in 5 days and more rain is expected. They are now talking weeks to reopen and requesting Federal disaster relief.]

Jared Polis, the governor via CBSlocal
“It’s diverting up against the highway in some areas causing more damage. Or against the other side of the river where it could eventually erode the railway,” said Executive Director of the Colorado Department of Public Safety Stan Hilkey.

The thin brown rods are rebar. The bigger, silver bars are post tensioning tendons. That means the entire slab is going to have to be removed and rebuilt. At least they can do two-way traffic on the lower road while they repair the upper road.
Jared Polis, the governor via CBSlocal
When the road is able to reopen it will likely be one-lane of traffic in each direction. Polis said he expects a fully operation interstate by the winter. “What’s really important is to get it fixed before ski season. There’s more alternatives in summer for safer travel and scenery. It’s absolutely critical to be fully functioning by ski season,” Polis said.
Drivers are being detoured up to Steamboat Springs, and truck drivers are urged to take Interstate 80 through Wyoming.
They are cancelling scheduled work on other roads in Colorado.

One mudslide broke through a retaining wall. The weather man predicts 3 to 4 inches of more rain in the next few days.

At least the monsoons should help Lake Mead recover. It has been at record lows.

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