I live in Crooked Creek near Old Fort. I work(ed) in Chimney Rock going on 11 years. My Dad and Step-Mom live near Garren Creek fire station. Your videos have been really informative and almost therapeutic. I've very much enjoyed your videos, and as emotionally difficult as this has been, I really like knowing the geological reasons for many of the events that took place. You are a very engaging educator. Thank you for all the Helene related content.
Please pass this information on to people you know that live in that area. I live in Oregon in the mountains. I can see this happening in my neighborhood. Plus if you live next to any size Creek you should have flood insurance. Period.
@@FluffylabellchatlaneOne of the real tragedies aside from the obvious destruction and loss of life is that many of the worst affected areas have just never experienced a flood event like this. The marker event in comparison in Western NC was in 1916. Some of these areas have only been inhabited since then, so they couldn't have known to insure against a flood because events like this here are rare. The last flooding event in Appalachia of this magnitude likely happened before the Europeans settled in the Americas.
mark huneycutt got some drone footage of a beginning point of a debris field [Chimney Rock area] that shows exactly what you illustrated about not always involving stream bed at the beginning point but the sheer rock faces and then flowing toward streams / rivers - fascinating as it was devastating. You've been explaining this event and how it happened so very well. I love learning even while feeling so sad for the reason the topic is upfront right now. I so hope folks like you and mark and others, combined with planning and preparedness organizations will take on and expand some of the hundreds of things we can learn from all this loss. Again, thank you!
@@bjjt-nu9dx Absolutely! He is also respectful of the tragedy at the same time he's sharing footage. It's how I ended up here, wanting to understand what I was seeing.
Dude, I live off of Vanderpool Road. 764 Will Perry Road, off of Vanderpool. The whole side of the mountain above my house slipped from the ridgeline. It wasn't a debris flow, the whole slope just dropped, and left bedrock exposed all the way to the ridgeline. There was a debris flow that went down the same flow path as the slip, but was caused by a log dam which had formed, and broke loose. My neighbor saw the resulting debris flow, and said it had a 20-30 foot tall wall of water pushing it. That's why these debris flows were as destructive as a dam breaking.
They are all related. When a slope fails, it initially becomes a landslide, because relatively little deformation occurs within the block of hillside that has moved. If the landslide continues, the material starts to deform internally, and it becomes a slump. If the slump continues, the material starts to break up into it's contituent parts and it becomes a debris flow. A debris is where the movement continues because all the pebbles and boulders are pushing each other along. It is not transported by water. However, the watercertainly helps to weaken the slopes and initiate slope failure, slides and slumps, then lubricate the debris flow once it gets going. We know all this because we can observe the process happening in real time. Also, we can recognise the resulting deposits in the geological record of the landscape. Landslides just look like a piece of land in the wrong place, with very little internal deformation. Slumps are also a pile of land in the wrong place, but internally very deformed and folded up. Whereas debris flow deposits, or debrites, are internally choatic and poorly sorted, because any structure that did exist has been totally mixed up by the transport process.
Yes because they used OPERATION POPEYE, WEATHER MODIFICATION, X OBAMA SIGNED THE EXECUTIVE ORDER WEATHER MODIFICATION USA OWNS THE WEATHER. LOOK IT UP. MAN MADE,CLOUD SEEDING. EVIL YES! Have you heard some lands have lithium to make batteries.? Investigation is needed.
So people don't know remember Tesla that invented the electricity well his patient was stolen now military improved it used for weather modification. Not normal these Hurricanes and STORMS, NO NOT NORMAL. 😮
@@geosamways Do you know of any educational animations , available to the public, that demonstrate these processes and show the difference in how the material looks after it comes to rest ?
That must have been terrifying to witness. I'm thankful you and your neighbor survived . My soul aches for all who went through this. And all remain in my prayers as you continue on the long road to recovery.
Thanks for these. I take back anything I said about evacuation warning failures - your take that we can inform ourselves about where to build - and where to Not build is well taken.
Until we have a complete working model of earth and quantum computing there's no way to predict what a natural disaster will do with any great certainty.. maybe in 50 years when AI and quantum computers are viable
In Japan where tsunamis occur there are engraved large rocks and boulders on the coastal hillsides which note where waters reached in old tsunamis imploring those who see them to not build below that point. They still build below these but they fully well know the risks their ancestors made sure they were warned about. This is a different situation but it's a foreseeable danger too. Sadly communities are going about rebuilding in the same places with this one as if it's not going to happen again. I love these hills but there are places- and lots of them- where you really shouldn't build or live throughout this area.
Thanks for your educational videos, they fascinate me. I myself experienced a flash flood episode in our local mountains one summer day! I personally heard the roar of tumbling boulder and whole logs of trees coming before we saw the WALL of mud headed for us. Suffice it to say we were all hoisted and airlifted by rescue helicopter out of there,… It was quite the adventure! Grateful we all made it out OK!
I live in a valley near Swannanoa which experienced several, possibly a dozen. Some of the bigger ones started below a classic rocky steep slope across the valley from us, like the ones illustrated here. But what struck me that Friday morning during Helene was the *sound* of it happening. When I head that powerful rush-clunk-thunking roar overtake the already-loud "background" sound of the creek flooding and eating trees, I knew something *big* had happened. I'm pretty sure I have the audio of one in a short video clip from that Friday morning. Sure enough, when the mist cleared, we could see several massive scars from our front porch on the opposing mountainside. Several more smaller ones had washed over the road below us. Downright powerful and scary.
I found John McPhee's essay about debris flows in the mountains of LA ("Los Angeles vs the Mountains") very difficult to visualize until I was in the foothills of the San Gabriels and walked around the perimeter of one of the debris flow catchment basins, and it is so deep and wide that I finally understood the enormous scale and power of these movements. Great video!
Thank you. I really appreciate your explanation and I have shared it. My Mother's family lines came from western NC and Greene County, TN. Back in the 1916 flood, my Great Grandmother was worried about her newly married daughter down the mountain (Madison County). She was a horsewoman and had her own riding horse so she rode down through the rain to warn her daughter of flash floods. She got there in time and the daughter only had time to grab her brand new Easter bonnet off the kitchen table that she had just bought. They climbed the hillside together with the horse and sure enough, they were safe but the house was washed away. Two years later my Great Grandmother died in the Spanish Flu along with another daughter and her newborn daughter. I've grown up with that story all my life and seeing this flood has given me perspective and it was even a worse flood than 1916. I've visited these areas all my life and it's fascinating to watch your video.
So interesting. I know all these places very well. I live in Madison county and we were luckily spared for the most part. Especially with debrief flows. I’m definitely checking out the topography of my area for future events. Thank you!! Very informative!!
There are several areas on the maps you've displayed that the LIDAR imaging is extremely telling of long past debris flows that far surpass the latest ones from Helene. In those craggy areas at the ridge tops with a lot of exposed rock, there were several that looked like the entire mountainside sagged into the lowlands below it. This is all fascinating to discuss and your recent videos of the various disaster areas (Pensacola, Chimney Rock, Swannanoa, Nolichucky Gorge, etc.) are by far the best description of why all this happened where it did. It would be fun (in an educational context) to be able to compare the topography of these areas prior to the 1916 floods and see if it could be determined how bad it was then as compared to this latest event.
Thank you so very much. Your thorough information and sketches really helped me make sense of some odd things various old timers/locals have said in conversations in videos and things that have been said about “the old roads”. Blessings.
I heard someone on the news that had lost their house to a slide. They said slides were worse than flooding in that you don’t know you are in danger, but that is not true. So many people build in a draw since it is easier to grade in steep terrain, but they need to look up hill at what is coming towards them before they buy or build a house. Water also tends to flow back into its original flow pattern, so keep that in mind. Also on the early slides that were shown to originate at two road locations, the way the State requires water quality is what produces that condition. We put a pipe in every concentrated flow location and the State made us take them all out. They only wanted pipes in the low spots and a lot of water being diverted and that just does not work. It over saturates soil high up in the draw which is what eventually fails. It also starves vegetation of water since the road cuts off drainage. We plan to fight back with the images you provided, so thanks. Lastly, everyone I have talked to that survived a slide said there was a little one, then a big one. I wonder why?
Each time you do one of these videos, it pulls more and more answers to questions I've had about how this all happened. We were worried about a landslide where we live in Banner Elk, but the mountain behind us is not super steep, nor are there any logging roads on it (an electricity road only) and I don't think there are rocky outcrops. Guessing with that much rain it might not matter. Water poured from behind us. The driveway to us and two neighbors looked like a raging creek. Our neighbors on the other road back here, clear cut next to us about a century or less ago to put Apple trees, and the mountain was concave behind them and it did landslide way back. We did have our electric company build a road a few years ago when they connected two substations with lines. That's more at the top and running down from the side. We worried about that for sure! We got lucky. I always wonder if the other side of the county (Avery) suffered more because of tree farms on the slopes of the mountains? I really enjoy you videos. It makes sense and makes you think!
With this storm, just about anywhere with some sort of slope irregularities seemed to have more landsliding. That will be evaluated further, but it certainly looks that way. Folks said that about the Watauga storm back in 1940, in terms of logged areas seeing more debris flows. With the amount of rain pre- and during Helene, pretty much all bets are off and just about anything that can go will go. When it comes to debris flows, though, you can get a sense of where they'll go, and you can build to avoid it or move yourself out of reach if you know epic rain is coming. There will be lots of study of where the debris flows came from during Helene...there were lots, and they exacted a huge toll.
Look it up Operation POPEYE CLOUD SEEDING PROTECT also used in Vietnam War 1967 that's how USA WON THE WAR BY WEATHER MODIFICATION.. USA OWNS THE WEATHER,OBAMA SIGNED THE EXECUTIVE ORDER WEATHER MODIFICATION. Operation cloud seeding to cause huge RAIN. MOISTEN LAND TO CAUSE MUD SLIDES! AMERICA WAKE UP!
@@TheGeoModels But sadly the government will not act to keep people from building or rebuilding in these dangerous areas. In Simpsonville SC south of this area there was a subdivision built in the 60's which was very prone to flooding and it took the government 40 years to address the problem by forbidding the rebuilding of any home there which was substantially damaged in a flood. Part of that deal was in the government agreeing to give some compensation to those who were affected or who voluntarily abandoned their home there. The NC mountain counties cannot afford anything similar to alleviate something like this from happening again, and most people are not going to be paying attention. Indeed plans to rebuild in those same places are ongoing now.
Back in the early 1900s all the higher mountains were logged and the roads you see is the old railroad grade. It started in Burnsville and went to Pensacola and up to the Wilson boundary and had switchbacks all the way to the top. All of the old railroad is on grade approximately 2.2 percent climb. On the east side of the mountain there was a different train that came up from the town of black mtn to the top of mt Mitchell. As you said some of the slides started at the edge of the old railroad on both sides of the mountain.
Those railroads were built to the lowest standard possible, with rock cuts minimal and 'fills' placed anywhere they were needed to ease the gradient. The thinking was that if they got washed out, they'd just fill them in again and keep going; no real thought was given to what might happen downhill from there. It's more than likely that the failure of some of these old fills initiated the events seen on this video.
You know. I've been back in the woods walking several times in different places of haywood county and seen a holler with a bunch of random rocks. Like 50 feet wide and as far up as you can see. I never once thought it being from land slides in the past. Pretty neat and scary at the same time. Gotta respect the mountains, she can and will take you out.
I come from a family that spent generations in Appalachia. This is something that farmers and homesteaders knew about. I suppose the newcomers to the area were not warned. I feel bad for them. They built houses in areas that my family wouldn’t even risk growing crops in. Living in the mountains is very different than living in a city where planners do a lot of the thinking for you. When you move to a rural area… YOU are responsible for the safety of your family, your animals, your belongings, and yourself.
I was born outside of Chicago and have lived for some 6 decades mostly in cities. I've never once thought or acted as if someone else was responsible for *my* safety.
@@IMSiegfried I salute you for that but a lot of people from the suburbs get dependent on someone else doing the thinking for them, maybe assuming that people with degrees know something that the rest of us don't know. Especially suburbanites who think that moving to the country is some kind of Disney utopia. It is not. I've lived in rural areas all of my life and would never live anywhere else, but it is not a utopia of any kind.
@@crowznest438 The big problem here is that there's been a large number of urban newbies flocking to this part of the world without a clue about living in the hills, and it is them who were most affected. See the "River Arts District" in Asheville to understand how blind to nature these people are. I've lived in many places including big cities but these hills are my home and I understand the beauty and the dangers and that if you want the beauty you have to accept the dangers and deal with them yourself.
I got stuck in a surprise storm in the Cherokee national forest while mountain biking. I was amazed at how a trail along the ridge could become a fast flowing 1 foot deep stream. I am convinced these roads and trails hold water that leads to catastrophic collapse.
the "rules" for making cuts in hillsides for trails state that it still must be slanted to drain downhill but I think they get the oppisite eroded into them in a storm or 2 and trap water like you stated then, eroding away the cut above them as they drain downhill.
To a degree, they do. Water doesn’t infiltrate into hard-packed earth or asphalt nearly as well soft forest soil. So those hard-packed dirt roads and trails will sort of act like impervious surface.
@ 24:46 This was a 100 yards up from us. Three houses were in that flow. An elderly couple in the first house it hit sadly perished. The next house down got balled up like a piece of paper, but all 4 occupants miraculously survived. It sounded like hell on earth.#wncstrong
Thank you for breaking this down for me. I live in Asheville closer to Weaverville and it's been very helpful to understand how and why this was so destructive.
Thank you so much for explaining how things happened to this area! Could you take a look at the landslides/mudslides that happened in the Busick/Hwy 80/Buck Creek area? I would love to see satellite imagery of the Buck Creek Landslide before it changes too much or gets grown over, it took the life of my friend and I'd like to understand what she went through in her last moments, it would help me. Thanks!
I'll try to do this on thursday. I'll ask--and you don't have to answer if it's too close--could you tell me where your friend was? Buck Creek got hit hard--very hard. there is a lot to talk about it with it.
Thank you so much for the informative Helene content you have been providing. I was looking out in the view from our town post-storm and have noticed several new scars in the landscape, one of which happens to be the Vanderpool flow. Fascinating to see the science behind it. Looking more into some of the “common signs” you have presented via the LiDAR imagery regarding my town and how we can better think about the future. Keep up the excellent videos - makes me feel like I’m back in college geology but with real world application in WNC!
Vanderpool was a close call. It was interesting to see it so quickly after it happened...the drone era is a different time. Hopefully we don't have to use this info much, but it's good to have it ahead of time just in case.
Doing research for a fellow gold hunter, alluvial and fluvial geology gives a great understanding of why landslides happen, or super-saturation of the ground surface by massive rains, causes disruption of the organic layer above a "high angle of repose" geology, creating land sloughing. Some of these high angles of repose are mountain "V" ravines and valleys, or glacier "U" shaped valleys, depends on the area's geological bedrock. Hard and dense bedrock (igneous granite, basalt, ..) will have a higher geological integrity, and high angles of repose. Sedimentary and metamorphic rock will be softer and have greater erosional processes with alluvial water erosion, and fluvial distribution of landslides screaming down from a high elevation to low elevation. Hillsides slide into lakes or valley bottoms. With the many glacial fjords around the planet, their landslides create tsunamis flooding out civilization and peoples. Landslides and their supersaturated land flows act like their own dirt tsunamis in lower elevations. The many eastern Appalachian mountain ranges and ridges of ancient Appalachia (250 MYA), and their softer sedimentary and metamorphic geology of sandstone, limestone, clays, silts, organic mudstones, siltstone, shales, slates, etc., makes them a continual situation for landslides and debris flows.
I'm looking so forward to watching this! You, sir, make me feel like a college student actually learning something! I'm definitely gonna get an A in my exam😂
back in the day if you could do me a little sketch you would get one! tried to split this by counties. it’s long, but I wanted to show patterns which is what it’s about thanks for the comment!
Is anyone looking at the threat of future flows because of the massive rainfall in late September? I watched a recent RUclips video where a gentleman walked up a debris flow track and I saw a lot of areas that could be a concern when it rains again. Thank you for the videos.
On Jan. 9, 2018, a series of early morning mudslides brought death and destruction down from the hills above Santa Barbara, taking 23 lives and injuring dozens more. PS - We never thought the hills along the SoCal coastline could produce this large a debris flow. There had been a fire on part of landscape. That rain event, previous rains and fires sent things in motion. RIP
More great observations. I think the key thing is identifying that debris flows initiate with landslides that ocurr where potentially unstable slopes fail. The unstable slopes could be natural scree slopes below outcrops, or they could be man made. It was very interesting to see that several debris flows seemed to originate at the road cuts. The excavation created banks of made ground, which were stabilised by the engineers under normal conditions, but destabilised by the excessive rainfall, triggering landslides that initiated debris flows.
I know its off the current topic but you had a vid about an old river flow in southern ohio caused by glaciers. Amazing. I live in cincinnati and lidar and elevation of my area makes me think the same channels are present in the little miami flood plain. The whitewater flood channel looks much different than the little miami and they are basically the same exact size and flow and only 20 miles apart. One has a huge mile wode valley and the other has a steep creek like formation. The little miami seems way to small to create the massive flat land area that houses lunken airport and areas futher upstream. A lot of the land near cincinnati looks intriguing on lidar after your vids. Ive always had a deep wonder about how cincinnati is seemingly the end of the glaciers and is the great transition between flat lands up north or the start of the appalachia hill range just in northern kentucky. A video on this area would be so cool. Thanks
@@TheGeoModels we love the videos! I'm not even in the states, but always loved geography in school. Thanks for reigniting my love for it almost 20 years later 🥰
You and Mark Hunycutt . I spelt his name wrong? But together so awesome understanding. I had no idea how beautiful and then devastating .😢. God bless and thank you
Sense. So refreshing! Thank you. We have Google earth. We can gain a higher perspective and we should use it. Also consider where waterways used to be before we damned, rerouted, etc. to suit our tastes. Clear cut spots for building upon or just selling timber, mining or drilling sites that have been abandoned and left tore up, weapons testing sites, etc. Dump sites. Living below these will create a whole new set of issues that slide hidden in the mud. Power lines. Railroad tracks. Roads. All provide perfect slide areas.
But you can tell that floods and debris flows have happened in the past in those areas. What is sad is that people building their homes didn’t realize they were building right on top of old debris flows from who knows how many years ago.
@@Fluffylabellchatlane yeah and these debris flows are pretty rare, i think the last flood like this was in 1916, 4 generations ago. so a lot of people would be focused on the immediate flood water threat and not even thinking about the landslide possibility.
Thank You Several years ago I purchased a little land in the Ozarks. I've never built mostly because of finances but also because there's just not the perfect spot. This little strip is also under a hill with a road above. We had a couple really heavy rains this year and although there were no mud slides there was severe washing. Exactly what you are saying happened on a small scale. A good portion of my neighbors up the hill top soil is now on my side of the fence. Thank You for explaining some of my natural fears.
For years, I noticed in the Appalachians what I call "rock rivers" uphill and down "dry"drainages on steep slopes inside hair pin curves. Lots of large rocks, from basketball to washing machine sized, but with mature trees growing in the rock fields, as if the rocks, once moving, are frozen in time. I thought the rock rivers were remnants of a glacial period where freezes would heave the rocks down hill bit by bit. After seeing this video, maybe they are older debris flows.
I wouldn’t be too surprised if a lot of these started right at old logging roads. If you think about how the flat surface of the logging road is built, it’s usually either cut into the hillside, built on fill on the hillside, or a mix of both. For those that are cut into the hillside, the face above the logging road is over-steepened compared to the rest of the slope, and there’s not much supporting the mountainside above it. For those on fill, the face of the embankment below the road is steeper than the rest of the hill, and there’s a whole bunch of extra weight on the hillside putting extra stress on the part of the hillside just below the embankment. And for the mixed option, you obviously get a bit of both. Either way, you end up with an over-steepened area of the hillside and some sort of discontinuity in the slope. So the logging road is going to serve as the natural initiation point for a landslide.
It might be helpful to understand the topography you live in by hiking up the streams. Visualize it in a raging rainstorm. A friend hired a geologist to hike the ravines uphill from her house. She shared that information with her neighbors too because people in our town have died from debris flows. We live just south of Saluda, NC. Flat landers come up here, don't understand this kind of flooding. It's so brutal.
I live in Tucson, AZ. We have some waterfalls/ponds that are essentially narrow canyons at the lower elevations of the 10,000-ft Catalina Mountains. Lots of young people party at these waterfalls/ponds in the early summer. Sometimes there are deaths because of rainfall up in the mountains that rapidly collect and flow down the canyons. People don’t realize how quickly a trickle of water can turn into a high wall of water. 😥 Not near as dangerous than what happened in western NC because NC’s floods included debris and mud.
Rocky out crops at the top of steep cliffs, steeper the cliff the more danger of land/mud slide. The material will generally follow the river bed but momentum can make it flow over the river banks. Thanks for the illustrated explanation.
Damn, these LIDAR images are wild. Go to about 7:40 and look at the mountain in the upper left corner of the picture in picture. Is that not just a giant sloughing-off? Looks like Mt. St. Helens.
there’s evidence for that. it would need to be confirmed, but those things have sat there for decades without seeing a Helene. with rain like it produced, anything that can go did. Watauga 1940 was like that, in that logged areas failed tremendously and made huge debris flows
@@TheGeoModels I could imagine the flat roads acting like dams that hold back water flowing down the hill, then collapsing, releasing all the water and dirt at once.
Great thanks out to you for this very valuable information to help string together the breadth and spread of this across the region. It is interesting how you could be just on the other side of the mountain an not see the flow. My wife's fathers family is from Riceville Community along Bull Creek just north and west of Swannanoa not too far from Warren Wilson College, and outside of flooding along the creek did not see the same level of debris flows.
I'm so glad to hear this! Years ago I built a log home off of Bull Creek Run across from the apple orchard. Have been hoping to hear how everyone there faired.
@@IMSiegfried What I know is from my wife's cousin, he did mention early on that the Community Center/Fire Station had flood damage from the creek. Dont know the extent of it.
First off thank you for this educational video. It helps me understand what actually took place during this event. Quick question. How long does it take for Google Maps to update clearer satellite images post Helene? I think that would be very eye opening how much the landscape has changed with this event.
Incredibly informative and visually helpful video. When i was stationed at Lewis, i used google earth to look at the lasting effects that Mt Ranier had when in the past it erupted, as well as when its activity caused lahars throughout the surrounding valleys. Very interesting and when i mentioned it to locals who i became friends with, they normally had zero knowledge on Ranier's history or possible lahars that could wipe them out in the future.
So a small debris flow starts high, high up at a ravine apex, It begins in a small area, maybe 400 sq. ft. or so by a depth of a foot or two. Essentially the weight of the load of a 9.5 yard concrete truck carrying an eight inch slump mix is released all at once at a 40 degree or so angle, the slope of the ravine. This 4 or 5 thousand lb. compact, liquid, kinetically energized load then gains kinetic energy at a fantastically rapid exponential rate. The miles of ravine material below, equally saturated, turns liquid then flows the instant it is disturbed from above.
Another great discussion about where the debris flows started and where they went in the NC mountains. Sad to hear that some of the flows hit homes with people inside. You probably saw that Mark Huneycutt went hiking up to the source of one debris flow that went down the steep slopes near Chimney Rock in a recent video. That was an extremely steep channel that was too steep to follow down on foot, but he flew his drone down. It passed several houses that seemed to be far enough from the creek and debris channel that they looked unharmed.
Firstly, thank you again for such a well thought out, explained, and illustrated explanation. From a planning perspective, we must advise folks not only on the possibility of the loss of life, but also on the prospective loss of property and property value. Again, that's not to say folks should never live in the mountains, but it's a factor. Even if people get an early enough warning to save their lives, they still stand a chance of losing their life's work. Sincerely, hope that doesn't come across as fear mongering. It's just a lot to chew on for me.
Need this out west , flash floods happen here .but they start miles away build speed and next thing ypu know your in a flood but no rain was in the area . Thankyou for your presentation excellent. So sad . I wouldnt build in mountains now but i dont know where is safe . A town in new mexico just flooded where no flood of its kind should of been . At least thats what we think 🤔
At 14:30 you were talking about debris flows coming off the steep mountain tops. Something else that I spotted in the Lidar image is what looks like a massive landslide that came off that same mountain top. Where it goes from the steep sided escarpment to what looks like a bumbled mess of hills may very well be body of the landslide. I might be all wrong about this of coarse. The only way to be sure would be to go and look at the hillside in person.
You would think these areas that did NOT encounter landslides are at an even higher risk for future events. I hope people are more aware. I was in Watauga County last week and headed to Rutherford soon, seeing these explanations are really helpful to understand how all this happened.
The one at Bee Tree, (27 min) looks like it has done that before, a few times, and will probably do that again. The LIDAR at 30 min, looks like there are older slides in that area as well, and maybe a weaker layer of subsoil from way back when, before tectonics raised and tilted that land.
And how many residents of old and new have settled along these slopes and purchased their dream homes without consideration of this? Quite unsettling, if it were me. As many folks have learned, I grew up knowing the Appalacians were considered the oldest mountain range in the US and quite eroded over time. If true, your presentation demonstrates that quite well with the wide debris fields long covered by vegetation. I did see this once while traveling in NC after a rainy week where a hillside was exposed down to rock and a house demolished below it. So it's not uncommon obviously. Good presentation. Thanks for sharing your knowledge.
I live in NC and have family and friends in the areas hit hard. In fact one of the fatalities in Haywood county is a member of my extended family. This destruction has never happened to this extent. This is a once in a 1000 year event. Parts of the land will never recover.
Another excellent video! I would love to see you checkout Buck Creek and North Cove in McDowell county and give us a breakdown! I am sure it's similar stuff but I'd love to hear you break it down!
Could U look at 959 Dillingham road, Barnardsville, NC? ?? My 3 brothers built a Log Cabin there. I have not been able to go to see if the Cabin is still standing. Cabin on corner of Dillingham, Stoney Fork UP on the mountain side.
A very good share, raising the issue of safety awareness....potential zoning, and property valuation. No matter....a few word otherwise...the LiDAR data exhibits areas at-risk .....for those in areas of mountain terrain it's a reality....as recently exhibited and sadly marked by fatalities. The medium resolution Ortho overlays politely communicate the level of disaster...where high resolution would have, may present, the harsh reality. #RRM #monitoring
Hi. Thank you for your videos! I live at the end of Haw Creek. I was looking at a topography map and it looks like one of the at risk areas you mentioned. How much rainfall would you say is a good indicator for when to move to a different area?
Thank you for these videos, they are very informative and I have been sharing with others who live in this area around me. I worked at a farm that was in the path of the Flat Creek event. I wanted to ask what kind of programs could I find to be able to study the lidar images?
Not sure about what's online for north carolina. I'm going to take a look tomorrow. You might see it through the US Geological Survey, but I don't know if they have the most recent lidar (best quality) up and running. I'll try to find out something.
something else that surprised me about this storm was the tornadoes. we usually say that tornadoes (from thunderstorms moving eastward) don’t successfully come over the mountains and make it into asheville. but was it the path of Helene and the gaps between the mountains that allowed tornadoes to happen?
The mountains don't stop tornadoes, but rather they tend to disrupt the spring and summer convective weather patterns which are conducive to the formation of tornadoes, so few form on this side of the mountains, and those which do form are usually weak and short-lived.Once past the mountains the convection becomes unimpeded and that's why there's plenty of them parallel to the mountains in the piedmont and foothills regions. Tornadoes can also form in strong low-level windshear environments like what happens with hurricanes, and these don't follow the usual spring and summer convective patterns or the directions those storms tend to go in. Tornadoes can move across the ground in any direction going downhill and uphill as they please into valley bottoms and across ridges, and they can be nearly stationary or travel as fast as 70MPH+. Even far from the core of a hurricane or tropical storm tornadoes can form because of the winds in the system, so beware of tornadoes when you're anywhere near one of these kinds of storms. These develop fast so there's usually no time to warn of them before they are on the ground.
Love your channel. I’m about to check and see if you’ve done anything about Tucson az. I deliver Amazon packages in the area and sometimes, in every direction you can see mountains. It’s amazing
Thank you for these amazing videos! Can you make a video that includes all of the affected areas in North Carolina- kind of like a quick summary- overview?
Phillip, I've enjoyed your videos. Thanks for the education. You said that landslides are a concern at any time that heavy rains fall. It made me wonder whether my house is at risk. We sit at the base of a couple of streams that fall from the mountains in Pisgah Forest. I wonder whether you could give an opinion of the level of risk of a landslide in Pisgah Forest.
@@IMSiegfried I've used the maps to view the valleys above me, but his videos show that the whole process must be started somewhere. As I understand it, there's usually a very steep area at the top where the landslide gets rolling. I'm at the bottom of a mountain. I'm just wondering whether there's anything above Pisgah Forest that looks like it might give way in heavy rainfall.
A first responder team leader would be confronted with an excruciatingly poignant dilemma, unparalleled in the realm of calamities. Does one, with full cognizance, imperil the lives of one’s own team by venturing into a grave and immediate danger, to rescue victims who, if they even survived, most assuredly suffered from grievous, life-threatening injuries inflicted by the initial surge of debris-whilst knowing that, at any moment, another such landslide is likely to descend, placing the entire team in jeopardy of the same fate, with little to no warning or chance to escape, all for another debris flow that may or may not happen, to rescue soul(s) who may or may not still be alive? Indeed an act of heroic valor, if in wartime would be deemed conspicuous gallantry meritorious of a congressional medal of honor.
Tony Garrison didn’t hesitate with the dilemma. After the first slide in Garren Creek he jumped into action to perform rescues. He had just pulled one woman free from the aftermath of the first slide when a second descended and carried him away. His funeral is today.
Strongly suspect that the hill tracks can easily become start points because of the way that upside slopes are excavated and deposited on the lower side giving two potential extra sources of loading. On the upside there will be drainage ditches which gather the rainfall (nominally to discharge it to the nearby stream/creek) but that gathered water will also add to the local soil saturation and cross slope pressures. Then on the outer/lower side the extra deposits of the extracted upslope rubble will have increased the local downhill slope with a slightly less compacted material providing a now saturated source for the flow. Flows have to start somewhere. In one sense, the hill tracks could be seen as equivalent to a fire break when looking back up-hill. It's unclear if the net effect is worse, or that it's just easy to blame, though comparison with avalanche slope 'management' bears careful consideration.
This is all well-known. Ask anyone who works in the coal mining business in West Virginia. What shocks me is all the building in these flood zones and along the hillsides where debris flow occurs. There are ways to mitigate it. Visit any strip mine in southern West Virginia to find out.
There are a few articles on chemical weathering, clay formation etc for that area… “The influence of climate and topography on rock-fragment abundance in modern fluival sands of the southern Blue Ridge Mountains, North Carolina” Journal of Sedimentary Research, 1 March 1988 J. H. Grantham | M. A. Velbel ----- “Rates and time scales of clay-mineral formation by weathering in saprolitic regoliths of the southern Appalachians from geochemical mass balance” Jason R. Price; Michael A. Velbel; Lina C. Patino GSA Bulletin, MAY 01, 2005 ----- “Geochemical mass balances and weathering rates in forested watersheds of the southern Blue Ridge II. Effects of botanical uptake terms” Allan B. Taylor, Michael Anthony Velbel Geoderma Volume 51, Issues 1-4, November 1991, Pages 29-50
I live in Crooked Creek near Old Fort. I work(ed) in Chimney Rock going on 11 years. My Dad and Step-Mom live near Garren Creek fire station.
Your videos have been really informative and almost therapeutic. I've very much enjoyed your videos, and as emotionally difficult as this has been, I really like knowing the geological reasons for many of the events that took place. You are a very engaging educator. Thank you for all the Helene related content.
Please pass this information on to people you know that live in that area. I live in Oregon in the mountains. I can see this happening in my neighborhood. Plus if you live next to any size Creek you should have flood insurance. Period.
I hope folks find value in it. It's quite an event to process. Thanks for your comment.
@@FluffylabellchatlaneOne of the real tragedies aside from the obvious destruction and loss of life is that many of the worst affected areas have just never experienced a flood event like this.
The marker event in comparison in Western NC was in 1916. Some of these areas have only been inhabited since then, so they couldn't have known to insure against a flood because events like this here are rare. The last flooding event in Appalachia of this magnitude likely happened before the Europeans settled in the Americas.
Be aware of radiation
@MtnMan-ny6vu Operation Popeye look it up
At this point, I consider your content as a must watch.
I'm sharing your videos on social media.
Simply outstanding.
thank you. very glad you find value in them!
@@TheGeoModelsYou are doing a wonderful public service.
Me too
mark huneycutt got some drone footage of a beginning point of a debris field [Chimney Rock area] that shows exactly what you illustrated about not always involving stream bed at the beginning point but the sheer rock faces and then flowing toward streams / rivers - fascinating as it was devastating. You've been explaining this event and how it happened so very well. I love learning even while feeling so sad for the reason the topic is upfront right now. I so hope folks like you and mark and others, combined with planning and preparedness organizations will take on and expand some of the hundreds of things we can learn from all this loss. Again, thank you!
Yes, I saw that
@@katiekofemug Huneycutt posted several excellent videos.
@@bjjt-nu9dx Absolutely! He is also respectful of the tragedy at the same time he's sharing footage. It's how I ended up here, wanting to understand what I was seeing.
Dude, I live off of Vanderpool Road.
764 Will Perry Road, off of Vanderpool.
The whole side of the mountain above my house slipped from the ridgeline.
It wasn't a debris flow, the whole slope just dropped, and left bedrock exposed all the way to the ridgeline.
There was a debris flow that went down the same flow path as the slip, but was caused by a log dam which had formed, and broke loose.
My neighbor saw the resulting debris flow, and said it had a 20-30 foot tall wall of water pushing it.
That's why these debris flows were as destructive as a dam breaking.
They are all related. When a slope fails, it initially becomes a landslide, because relatively little deformation occurs within the block of hillside that has moved. If the landslide continues, the material starts to deform internally, and it becomes a slump. If the slump continues, the material starts to break up into it's contituent parts and it becomes a debris flow. A debris is where the movement continues because all the pebbles and boulders are pushing each other along. It is not transported by water. However, the watercertainly helps to weaken the slopes and initiate slope failure, slides and slumps, then lubricate the debris flow once it gets going.
We know all this because we can observe the process happening in real time. Also, we can recognise the resulting deposits in the geological record of the landscape. Landslides just look like a piece of land in the wrong place, with very little internal deformation. Slumps are also a pile of land in the wrong place, but internally very deformed and folded up. Whereas debris flow deposits, or debrites, are internally choatic and poorly sorted, because any structure that did exist has been totally mixed up by the transport process.
Yes because they used OPERATION POPEYE, WEATHER MODIFICATION, X OBAMA SIGNED THE EXECUTIVE ORDER WEATHER MODIFICATION USA OWNS THE WEATHER. LOOK IT UP. MAN MADE,CLOUD SEEDING. EVIL YES! Have you heard some lands have lithium to make batteries.? Investigation is needed.
So people don't know remember Tesla that invented the electricity well his patient was stolen now military improved it used for weather modification. Not normal these Hurricanes and STORMS, NO NOT NORMAL. 😮
@@geosamways Do you know of any educational animations , available to the public, that demonstrate these processes and show the difference in how the material looks after it comes to rest ?
That must have been terrifying to witness. I'm thankful you and your neighbor survived . My soul aches for all who went through this. And all remain in my prayers as you continue on the long road to recovery.
Thanks for these. I take back anything I said about evacuation warning failures - your take that we can inform ourselves about where to build - and where to Not build is well taken.
it’s tough question to answer
Until we have a complete working model of earth and quantum computing there's no way to predict what a natural disaster will do with any great certainty.. maybe in 50 years when AI and quantum computers are viable
In Japan where tsunamis occur there are engraved large rocks and boulders on the coastal hillsides which note where waters reached in old tsunamis imploring those who see them to not build below that point. They still build below these but they fully well know the risks their ancestors made sure they were warned about. This is a different situation but it's a foreseeable danger too. Sadly communities are going about rebuilding in the same places with this one as if it's not going to happen again. I love these hills but there are places- and lots of them- where you really shouldn't build or live throughout this area.
Thanks for your educational videos, they fascinate me. I myself experienced a flash flood episode in our local mountains one summer day! I personally heard the roar of tumbling boulder and whole logs of trees coming before we saw the WALL of mud headed for us. Suffice it to say we were all hoisted and airlifted by rescue helicopter out of there,… It was quite the adventure! Grateful we all made it out OK!
For those of us far away, I found your videos worth sharing, to try and make sense of how vast this became. Thank you for making it understandable.
glad to help
I admire your diplomacy in giving warnings.
I live in a valley near Swannanoa which experienced several, possibly a dozen. Some of the bigger ones started below a classic rocky steep slope across the valley from us, like the ones illustrated here. But what struck me that Friday morning during Helene was the *sound* of it happening. When I head that powerful rush-clunk-thunking roar overtake the already-loud "background" sound of the creek flooding and eating trees, I knew something *big* had happened. I'm pretty sure I have the audio of one in a short video clip from that Friday morning.
Sure enough, when the mist cleared, we could see several massive scars from our front porch on the opposing mountainside. Several more smaller ones had washed over the road below us.
Downright powerful and scary.
Hugely understandable now. Thank you for the explanation.
I’m glad it was understandable. not an everyday topic, so I try to illustrate as best I can.
I found John McPhee's essay about debris flows in the mountains of LA ("Los Angeles vs the Mountains") very difficult to visualize until I was in the foothills of the San Gabriels and walked around the perimeter of one of the debris flow catchment basins, and it is so deep and wide that I finally understood the enormous scale and power of these movements. Great video!
Thank you. I really appreciate your explanation and I have shared it. My Mother's family lines came from western NC and Greene County, TN. Back in the 1916 flood, my Great Grandmother was worried about her newly married daughter down the mountain (Madison County). She was a horsewoman and had her own riding horse so she rode down through the rain to warn her daughter of flash floods. She got there in time and the daughter only had time to grab her brand new Easter bonnet off the kitchen table that she had just bought. They climbed the hillside together with the horse and sure enough, they were safe but the house was washed away. Two years later my Great Grandmother died in the Spanish Flu along with another daughter and her newborn daughter. I've grown up with that story all my life and seeing this flood has given me perspective and it was even a worse flood than 1916. I've visited these areas all my life and it's fascinating to watch your video.
The Bob Ross of Geology.
get my easel and brush
😂👍🏻
We'll just put this happy little cabin right here in some trees. And then here comes this little debris flow...
So interesting. I know all these places very well. I live in Madison county and we were luckily spared for the most part. Especially with debrief flows. I’m definitely checking out the topography of my area for future events. Thank you!! Very informative!!
There are several areas on the maps you've displayed that the LIDAR imaging is extremely telling of long past debris flows that far surpass the latest ones from Helene. In those craggy areas at the ridge tops with a lot of exposed rock, there were several that looked like the entire mountainside sagged into the lowlands below it. This is all fascinating to discuss and your recent videos of the various disaster areas (Pensacola, Chimney Rock, Swannanoa, Nolichucky Gorge, etc.) are by far the best description of why all this happened where it did. It would be fun (in an educational context) to be able to compare the topography of these areas prior to the 1916 floods and see if it could be determined how bad it was then as compared to this latest event.
Comparison likely to be a video down the road
@@TheGeoModels I look forward to that!
Thank you so very much. Your thorough information and sketches really helped me make sense of some odd things various old timers/locals have said in conversations in videos and things that have been said about “the old roads”. Blessings.
Thanks for your comment. Glad the video was useful.
I heard someone on the news that had lost their house to a slide. They said slides were worse than flooding in that you don’t know you are in danger, but that is not true. So many people build in a draw since it is easier to grade in steep terrain, but they need to look up hill at what is coming towards them before they buy or build a house. Water also tends to flow back into its original flow pattern, so keep that in mind. Also on the early slides that were shown to originate at two road locations, the way the State requires water quality is what produces that condition. We put a pipe in every concentrated flow location and the State made us take them all out. They only wanted pipes in the low spots and a lot of water being diverted and that just does not work. It over saturates soil high up in the draw which is what eventually fails. It also starves vegetation of water since the road cuts off drainage. We plan to fight back with the images you provided, so thanks. Lastly, everyone I have talked to that survived a slide said there was a little one, then a big one. I wonder why?
Yes please fight for proper drainage!
Each time you do one of these videos, it pulls more and more answers to questions I've had about how this all happened. We were worried about a landslide where we live in Banner Elk, but the mountain behind us is not super steep, nor are there any logging roads on it (an electricity road only) and I don't think there are rocky outcrops. Guessing with that much rain it might not matter. Water poured from behind us. The driveway to us and two neighbors looked like a raging creek. Our neighbors on the other road back here, clear cut next to us about a century or less ago to put Apple trees, and the mountain was concave behind them and it did landslide way back. We did have our electric company build a road a few years ago when they connected two substations with lines. That's more at the top and running down from the side. We worried about that for sure! We got lucky. I always wonder if the other side of the county (Avery) suffered more because of tree farms on the slopes of the mountains? I really enjoy you videos. It makes sense and makes you think!
With this storm, just about anywhere with some sort of slope irregularities seemed to have more landsliding. That will be evaluated further, but it certainly looks that way. Folks said that about the Watauga storm back in 1940, in terms of logged areas seeing more debris flows. With the amount of rain pre- and during Helene, pretty much all bets are off and just about anything that can go will go. When it comes to debris flows, though, you can get a sense of where they'll go, and you can build to avoid it or move yourself out of reach if you know epic rain is coming. There will be lots of study of where the debris flows came from during Helene...there were lots, and they exacted a huge toll.
Look it up Operation POPEYE CLOUD SEEDING PROTECT also used in Vietnam War 1967 that's how USA WON THE WAR BY WEATHER MODIFICATION.. USA OWNS THE WEATHER,OBAMA SIGNED THE EXECUTIVE ORDER WEATHER MODIFICATION. Operation cloud seeding to cause huge RAIN. MOISTEN LAND TO CAUSE MUD SLIDES! AMERICA WAKE UP!
@@TheGeoModels But sadly the government will not act to keep people from building or rebuilding in these dangerous areas. In Simpsonville SC south of this area there was a subdivision built in the 60's which was very prone to flooding and it took the government 40 years to address the problem by forbidding the rebuilding of any home there which was substantially damaged in a flood. Part of that deal was in the government agreeing to give some compensation to those who were affected or who voluntarily abandoned their home there. The NC mountain counties cannot afford anything similar to alleviate something like this from happening again, and most people are not going to be paying attention. Indeed plans to rebuild in those same places are ongoing now.
Back in the early 1900s all the higher mountains were logged and the roads you see is the old railroad grade. It started in Burnsville and went to Pensacola and up to the Wilson boundary and had switchbacks all the way to the top. All of the old railroad is on grade approximately 2.2 percent climb. On the east side of the mountain there was a different train that came up from the town of black mtn to the top of mt Mitchell. As you said some of the slides started at the edge of the old railroad on both sides of the mountain.
Those railroads were built to the lowest standard possible, with rock cuts minimal and 'fills' placed anywhere they were needed to ease the gradient. The thinking was that if they got washed out, they'd just fill them in again and keep going; no real thought was given to what might happen downhill from there. It's more than likely that the failure of some of these old fills initiated the events seen on this video.
You know. I've been back in the woods walking several times in different places of haywood county and seen a holler with a bunch of random rocks. Like 50 feet wide and as far up as you can see. I never once thought it being from land slides in the past. Pretty neat and scary at the same time. Gotta respect the mountains, she can and will take you out.
Thats why mountain people are generally some of the toughest
@mattb6646 Yes sir. You got that right.
I come from a family that spent generations in Appalachia. This is something that farmers and homesteaders knew about. I suppose the newcomers to the area were not warned. I feel bad for them. They built houses in areas that my family wouldn’t even risk growing crops in. Living in the mountains is very different than living in a city where planners do a lot of the thinking for you. When you move to a rural area… YOU are responsible for the safety of your family, your animals, your belongings, and yourself.
I was born outside of Chicago and have lived for some 6 decades mostly in cities. I've never once thought or acted as if someone else was responsible for *my* safety.
@@IMSiegfried I salute you for that but a lot of people from the suburbs get dependent on someone else doing the thinking for them, maybe assuming that people with degrees know something that the rest of us don't know. Especially suburbanites who think that moving to the country is some kind of Disney utopia. It is not. I've lived in rural areas all of my life and would never live anywhere else, but it is not a utopia of any kind.
Thank You
@@crowznest438 The big problem here is that there's been a large number of urban newbies flocking to this part of the world without a clue about living in the hills, and it is them who were most affected. See the "River Arts District" in Asheville to understand how blind to nature these people are. I've lived in many places including big cities but these hills are my home and I understand the beauty and the dangers and that if you want the beauty you have to accept the dangers and deal with them yourself.
@@P_RO_ 100%; we love these hills and we know them pretty well!
I got stuck in a surprise storm in the Cherokee national forest while mountain biking. I was amazed at how a trail along the ridge could become a fast flowing 1 foot deep stream. I am convinced these roads and trails hold water that leads to catastrophic collapse.
the "rules" for making cuts in hillsides for trails state that it still must be slanted to drain downhill but I think they get the oppisite eroded into them in a storm or 2 and trap water like you stated then, eroding away the cut above them as they drain downhill.
To a degree, they do. Water doesn’t infiltrate into hard-packed earth or asphalt nearly as well soft forest soil. So those hard-packed dirt roads and trails will sort of act like impervious surface.
@ 24:46 This was a 100 yards up from us. Three houses were in that flow. An elderly couple in the first house it hit sadly perished. The next house down got balled up like a piece of paper, but all 4 occupants miraculously survived. It sounded like hell on earth.#wncstrong
With that drop in elevation, those folks never had a chance.
Please share this man’s channel with all of your neighbors. People need to know before they rebuild
@@FluffylabellchatlaneNo one is rebuilding there, believe me.
That one looked bad. Was the couple the Dockerys? I read about them recently. It's truly a miracle that 4 people survived in that other house.
Were you home when it all happened?
Thank you for breaking this down for me. I live in Asheville closer to Weaverville and it's been very helpful to understand how and why this was so destructive.
Thank you so much for these informative and fascinating videos. Whenever I see a new one of your videos in my feed, I always click it on immediately.
Thank you so much for explaining how things happened to this area! Could you take a look at the landslides/mudslides that happened in the Busick/Hwy 80/Buck Creek area? I would love to see satellite imagery of the Buck Creek Landslide before it changes too much or gets grown over, it took the life of my friend and I'd like to understand what she went through in her last moments, it would help me. Thanks!
next or 2nd upcoming vid. yes, it’s dramatic. I was working up in there before all of this. it’s different now.
I'm so sorry for your loss.
I'll try to do this on thursday. I'll ask--and you don't have to answer if it's too close--could you tell me where your friend was? Buck Creek got hit hard--very hard. there is a lot to talk about it with it.
Thank you so much for the informative Helene content you have been providing. I was looking out in the view from our town post-storm and have noticed several new scars in the landscape, one of which happens to be the Vanderpool flow. Fascinating to see the science behind it. Looking more into some of the “common signs” you have presented via the LiDAR imagery regarding my town and how we can better think about the future. Keep up the excellent videos - makes me feel like I’m back in college geology but with real world application in WNC!
Vanderpool was a close call. It was interesting to see it so quickly after it happened...the drone era is a different time. Hopefully we don't have to use this info much, but it's good to have it ahead of time just in case.
@@TheGeoModels so many drones have assisted in SAR and data collection post-storm, quite an incredibly useful tool!
Doing research for a fellow gold hunter, alluvial and fluvial geology gives a great understanding of why landslides happen, or super-saturation of the ground surface by massive rains, causes disruption of the organic layer above a "high angle of repose" geology, creating land sloughing.
Some of these high angles of repose are mountain "V" ravines and valleys, or glacier "U" shaped valleys, depends on the area's geological bedrock. Hard and dense bedrock (igneous granite, basalt, ..) will have a higher geological integrity, and high angles of repose. Sedimentary and metamorphic rock will be softer and have greater erosional processes with alluvial water erosion, and fluvial distribution of landslides screaming down from a high elevation to low elevation. Hillsides slide into lakes or valley bottoms. With the many glacial fjords around the planet, their landslides create tsunamis flooding out civilization and peoples. Landslides and their supersaturated land flows act like their own dirt tsunamis in lower elevations.
The many eastern Appalachian mountain ranges and ridges of ancient Appalachia (250 MYA), and their softer sedimentary and metamorphic geology of sandstone, limestone, clays, silts, organic mudstones, siltstone, shales, slates, etc., makes them a continual situation for landslides and debris flows.
I'm looking so forward to watching this! You, sir, make me feel like a college student actually learning something! I'm definitely gonna get an A in my exam😂
back in the day if you could do me a little sketch you would get one! tried to split this by counties. it’s long, but I wanted to show patterns which is what it’s about
thanks for the comment!
@TheGeoModels Absolutely! I have subscribed to your channel! Thanks again 🙂
Gravity always wins.Thanks again for this Sir! My heart goes out to all the good people who lived here 🙏🏼
I have been telling people about your channel in the comment section on RUclips. Thanks for the info.
thanks for watching. hope it was useful!
Is anyone looking at the threat of future flows because of the massive rainfall in late September? I watched a recent RUclips video where a gentleman walked up a debris flow track and I saw a lot of areas that could be a concern when it rains again. Thank you for the videos.
yes, it’s evaluated in some places. I tell anyone in potential reach of one that already happened to be elsewhere when the first big rain comes.
On Jan. 9, 2018, a series of early morning mudslides brought death and destruction down from the hills above Santa Barbara, taking 23 lives and injuring dozens more.
PS - We never thought the hills along the SoCal coastline could produce this large a debris flow. There had been a fire on part of landscape. That rain event, previous rains and fires sent things in motion. RIP
Your presentations on Helene are excellent! They BRING GEOLOGY TO LIFE!!
More great observations. I think the key thing is identifying that debris flows initiate with landslides that ocurr where potentially unstable slopes fail. The unstable slopes could be natural scree slopes below outcrops, or they could be man made. It was very interesting to see that several debris flows seemed to originate at the road cuts. The excavation created banks of made ground, which were stabilised by the engineers under normal conditions, but destabilised by the excessive rainfall, triggering landslides that initiated debris flows.
Superb content. Thank you. You're providing a true public service. God bless you. TFS
I know its off the current topic but you had a vid about an old river flow in southern ohio caused by glaciers. Amazing. I live in cincinnati and lidar and elevation of my area makes me think the same channels are present in the little miami flood plain. The whitewater flood channel looks much different than the little miami and they are basically the same exact size and flow and only 20 miles apart. One has a huge mile wode valley and the other has a steep creek like formation. The little miami seems way to small to create the massive flat land area that houses lunken airport and areas futher upstream. A lot of the land near cincinnati looks intriguing on lidar after your vids. Ive always had a deep wonder about how cincinnati is seemingly the end of the glaciers and is the great transition between flat lands up north or the start of the appalachia hill range just in northern kentucky. A video on this area would be so cool. Thanks
The information is superb. Helps to understand
thank you
Thank you so much for these videos. They are very helpful and informative. I live in East Tennessee.
Glad they are useful
Fascinating stuff. 10/10 break down.
You are the best Geology professor I’ve ever had!
THANK YOU SOOOOOO FOR TRYING TO HELP ME TO UNDERSTAND..THANKS FOR YOUR TIME AND HARD WORK..
So interesting and sad. Excellent info.
Developing a major crush on the geomodels guy. These videos are excellent!
I would put my real name on it but it’s locked up by Virginia Tech due to a Google-Microsoft shift. glad folks at least like the videos!
@@TheGeoModels we love the videos! I'm not even in the states, but always loved geography in school. Thanks for reigniting my love for it almost 20 years later 🥰
@ 23:00 That's the Black Mountain Home for Boys. It was the FH Camp before that. Beautiful property.
Were folks up there? It's hard to tell how bad that one was, but given its size and where the buildings are it could have been very serious.
You and Mark Hunycutt . I spelt his name wrong? But together so awesome understanding. I had no idea how beautiful and then devastating .😢. God bless and thank you
his videos are a great resource
Sense. So refreshing! Thank you. We have Google earth. We can gain a higher perspective and we should use it. Also consider where waterways used to be before we damned, rerouted, etc. to suit our tastes. Clear cut spots for building upon or just selling timber, mining or drilling sites that have been abandoned and left tore up, weapons testing sites, etc. Dump sites. Living below these will create a whole new set of issues that slide hidden in the mud. Power lines. Railroad tracks. Roads. All provide perfect slide areas.
Thank you for explaining it clearly
Keep up the good work 👍👍👍
a lot of those debris flows happened in Nelson County, VA when Camille stalled for 12 hours and just dumped 30+ inches
But you can tell that floods and debris flows have happened in the past in those areas. What is sad is that people building their homes didn’t realize they were building right on top of old debris flows from who knows how many years ago.
@@Fluffylabellchatlane yeah and these debris flows are pretty rare, i think the last flood like this was in 1916, 4 generations ago. so a lot of people would be focused on the immediate flood water threat and not even thinking about the landslide possibility.
Thank You
Several years ago I purchased a little land in the Ozarks. I've never built mostly because of finances but also because there's just not the perfect spot. This little strip is also under a hill with a road above.
We had a couple really heavy rains this year and although there were no mud slides there was severe washing. Exactly what you are saying happened on a small scale. A good portion of my neighbors up the hill top soil is now on my side of the fence. Thank You for explaining some of my natural fears.
I really enjoy learning from your videos
Happy to hear you find them useful
Excellent presentation that explained what happened in this area.
Thank you
Thank you. M
glad you found it helpful. thanks for the comment.
For years, I noticed in the Appalachians what I call "rock rivers" uphill and down "dry"drainages on steep slopes inside hair pin curves. Lots of large rocks, from basketball to washing machine sized, but with mature trees growing in the rock fields, as if the rocks, once moving, are frozen in time. I thought the rock rivers were remnants of a glacial period where freezes would heave the rocks down hill bit by bit. After seeing this video, maybe they are older debris flows.
I wouldn’t be too surprised if a lot of these started right at old logging roads. If you think about how the flat surface of the logging road is built, it’s usually either cut into the hillside, built on fill on the hillside, or a mix of both. For those that are cut into the hillside, the face above the logging road is over-steepened compared to the rest of the slope, and there’s not much supporting the mountainside above it. For those on fill, the face of the embankment below the road is steeper than the rest of the hill, and there’s a whole bunch of extra weight on the hillside putting extra stress on the part of the hillside just below the embankment. And for the mixed option, you obviously get a bit of both. Either way, you end up with an over-steepened area of the hillside and some sort of discontinuity in the slope. So the logging road is going to serve as the natural initiation point for a landslide.
It might be helpful to understand the topography you live in by hiking up the streams. Visualize it in a raging rainstorm. A friend hired a geologist to hike the ravines uphill from her house. She shared that information with her neighbors too because people in our town have died from debris flows. We live just south of Saluda, NC. Flat landers come up here, don't understand this kind of flooding. It's so brutal.
going to do one on Big Hungry River above Green River soon. Was working out on 176 recently. Everythings a mess!
I live in Tucson, AZ. We have some waterfalls/ponds that are essentially narrow canyons at the lower elevations of the 10,000-ft Catalina Mountains. Lots of young people party at these waterfalls/ponds in the early summer. Sometimes there are deaths because of rainfall up in the mountains that rapidly collect and flow down the canyons. People don’t realize how quickly a trickle of water can turn into a high wall of water. 😥 Not near as dangerous than what happened in western NC because NC’s floods included debris and mud.
Rocky out crops at the top of steep cliffs, steeper the cliff the more danger of land/mud slide. The material will generally follow the river bed but momentum can make it flow over the river banks. Thanks for the illustrated explanation.
Damn, these LIDAR images are wild. Go to about 7:40 and look at the mountain in the upper left corner of the picture in picture. Is that not just a giant sloughing-off? Looks like Mt. St. Helens.
It definitely looked like the flows may have started on the old road beds high in the mountains
there’s evidence for that. it would need to be confirmed, but those things have sat there for decades without seeing a Helene. with rain like it produced, anything that can go did. Watauga 1940 was like that, in that logged areas failed tremendously and made huge debris flows
Perhaps there were tornados up there
@@TheGeoModels I could imagine the flat roads acting like dams that hold back water flowing down the hill, then collapsing, releasing all the water and dirt at once.
Great thanks out to you for this very valuable information to help string together the breadth and spread of this across the region. It is interesting how you could be just on the other side of the mountain an not see the flow. My wife's fathers family is from Riceville Community along Bull Creek just north and west of Swannanoa not too far from Warren Wilson College, and outside of flooding along the creek did not see the same level of debris flows.
I'm so glad to hear this! Years ago I built a log home off of Bull Creek Run across from the apple orchard. Have been hoping to hear how everyone there faired.
@@IMSiegfried What I know is from my wife's cousin, he did mention early on that the Community Center/Fire Station had flood damage from the creek. Dont know the extent of it.
never clicked so fast
it was fast indeed!
First off thank you for this educational video. It helps me understand what actually took place during this event. Quick question. How long does it take for Google Maps to update clearer satellite images post Helene? I think that would be very eye opening how much the landscape has changed with this event.
Excellent description of geological events. Learn something every time. Great job! Better than my Geology 101 instructor back in the college days!
Good content….i like the presentation…simple….hard to find any chunks in ur assertions…good way to illustrate the danger as well…
Dude you are like the Bob Ross of MSPAINT!! “ A little tree here…debris flow there!!!…”. Lol
there will probly be trees in the next one
Thank, great information!
Incredibly informative and visually helpful video. When i was stationed at Lewis, i used google earth to look at the lasting effects that Mt Ranier had when in the past it erupted, as well as when its activity caused lahars throughout the surrounding valleys. Very interesting and when i mentioned it to locals who i became friends with, they normally had zero knowledge on Ranier's history or possible lahars that could wipe them out in the future.
So a small debris flow starts high, high up at a ravine apex, It begins in a small area, maybe 400 sq. ft. or so by a depth of a foot or two. Essentially the weight of the load of a 9.5 yard concrete truck carrying an eight inch slump mix is released all at once at a 40 degree or so angle, the slope of the ravine. This 4 or 5 thousand lb. compact, liquid, kinetically energized load then gains kinetic energy at a fantastically rapid exponential rate. The miles of ravine material below, equally saturated, turns liquid then flows the instant it is disturbed from above.
Another great discussion about where the debris flows started and where they went in the NC mountains. Sad to hear that some of the flows hit homes with people inside.
You probably saw that Mark Huneycutt went hiking up to the source of one debris flow that went down the steep slopes near Chimney Rock in a recent video. That was an extremely steep channel that was too steep to follow down on foot, but he flew his drone down. It passed several houses that seemed to be far enough from the creek and debris channel that they looked unharmed.
Firstly, thank you again for such a well thought out, explained, and illustrated explanation. From a planning perspective, we must advise folks not only on the possibility of the loss of life, but also on the prospective loss of property and property value. Again, that's not to say folks should never live in the mountains, but it's a factor. Even if people get an early enough warning to save their lives, they still stand a chance of losing their life's work. Sincerely, hope that doesn't come across as fear mongering. It's just a lot to chew on for me.
I hope people take into account geology before they rebuild.
My mother lived off Toodies Creek. That debris flow had 2 confirmed fatalities in a house.
Hate to hear that. Toodies has some features in common with Peeks Creek in Macon which was terrible in 2004.
Thank you for your videos! They are so very informative. Love these.
thank you
Need this out west , flash floods happen here .but they start miles away build speed and next thing ypu know your in a flood but no rain was in the area .
Thankyou for your presentation excellent. So sad . I wouldnt build in mountains now but i dont know where is safe . A town in new mexico just flooded where no flood of its kind should of been . At least thats what we think 🤔
At 14:30 you were talking about debris flows coming off the steep mountain tops. Something else that I spotted in the Lidar image is what looks like a massive landslide that came off that same mountain top. Where it goes from the steep sided escarpment to what looks like a bumbled mess of hills may very well be body of the landslide. I might be all wrong about this of coarse. The only way to be sure would be to go and look at the hillside in person.
I needed this explained and makes sense now. Thank you.
You would think these areas that did NOT encounter landslides are at an even higher risk for future events. I hope people are more aware. I was in Watauga County last week and headed to Rutherford soon, seeing these explanations are really helpful to understand how all this happened.
LIDAR is wonderful. This video should be watched by anyone considering buying mountain property.
Another great video - very appreciated.
The one at Bee Tree, (27 min) looks like it has done that before, a few times, and will probably do that again. The LIDAR at 30 min, looks like there are older slides in that area as well, and maybe a weaker layer of subsoil from way back when, before tectonics raised and tilted that land.
Anxiously awaiting the French Broad analysis, for Marshall and Hot Springs
Geeze. I watched the video but didn't see what you're seeing. What am I missing? Please and thank you.
Such an informative and well-done series!
Made me think about that cabin I rented in Oregon in a hollow on the upper Rogue River.
And how many residents of old and new have settled along these slopes and purchased their dream homes without consideration of this? Quite unsettling, if it were me. As many folks have learned, I grew up knowing the Appalacians were considered the oldest mountain range in the US and quite eroded over time. If true, your presentation demonstrates that quite well with the wide debris fields long covered by vegetation. I did see this once while traveling in NC after a rainy week where a hillside was exposed down to rock and a house demolished below it. So it's not uncommon obviously. Good presentation. Thanks for sharing your knowledge.
I live in NC and have family and friends in the areas hit hard. In fact one of the fatalities in Haywood county is a member of my extended family. This destruction has never happened to this extent. This is a once in a 1000 year event. Parts of the land will never recover.
Thanks for your knowledge and insight. For next video will you explain Asheville flooding on French Broad river system?
Yes, I am working my way towards French Broad.
You are a great teacher.
So informative.
Another excellent video! I would love to see you checkout Buck Creek and North Cove in McDowell county and give us a breakdown! I am sure it's similar stuff but I'd love to hear you break it down!
yes it is coming. thank you for watching
Could U look at 959 Dillingham road, Barnardsville, NC? ?? My 3 brothers built a Log Cabin there. I have not been able to go to see if the Cabin is still standing. Cabin on corner of Dillingham, Stoney Fork UP on the mountain side.
Did not know I was interested in this content. Liked and subscribed.
A very good share, raising the issue of safety awareness....potential zoning, and property valuation. No matter....a few word otherwise...the LiDAR data exhibits areas at-risk .....for those in areas of mountain terrain it's a reality....as recently exhibited and sadly marked by fatalities.
The medium resolution Ortho overlays politely communicate the level of disaster...where high resolution would have, may present, the harsh reality.
#RRM #monitoring
Super interesting thank you
Hi. Thank you for your videos! I live at the end of Haw Creek. I was looking at a topography map and it looks like one of the at risk areas you mentioned. How much rainfall would you say is a good indicator for when to move to a different area?
He's said 5".
@@IMSiegfried thank you!
Thank you for these videos, they are very informative and I have been sharing with others who live in this area around me. I worked at a farm that was in the path of the Flat Creek event. I wanted to ask what kind of programs could I find to be able to study the lidar images?
Not sure about what's online for north carolina. I'm going to take a look tomorrow. You might see it through the US Geological Survey, but I don't know if they have the most recent lidar (best quality) up and running. I'll try to find out something.
something else that surprised me about this storm was the tornadoes. we usually say that tornadoes (from thunderstorms moving eastward) don’t successfully come over the mountains and make it into asheville. but was it the path of Helene and the gaps between the mountains that allowed tornadoes to happen?
The tornadoes occurred on the wrong side of the slopes. Not the north-west to south-east track they usually take.
Don't know but here in Florida there were 27 tornadoes which is highly unusual for FL.
The mountains don't stop tornadoes, but rather they tend to disrupt the spring and summer convective weather patterns which are conducive to the formation of tornadoes, so few form on this side of the mountains, and those which do form are usually weak and short-lived.Once past the mountains the convection becomes unimpeded and that's why there's plenty of them parallel to the mountains in the piedmont and foothills regions. Tornadoes can also form in strong low-level windshear environments like what happens with hurricanes, and these don't follow the usual spring and summer convective patterns or the directions those storms tend to go in. Tornadoes can move across the ground in any direction going downhill and uphill as they please into valley bottoms and across ridges, and they can be nearly stationary or travel as fast as 70MPH+. Even far from the core of a hurricane or tropical storm tornadoes can form because of the winds in the system, so beware of tornadoes when you're anywhere near one of these kinds of storms. These develop fast so there's usually no time to warn of them before they are on the ground.
Love your channel. I’m about to check and see if you’ve done anything about Tucson az. I deliver Amazon packages in the area and sometimes, in every direction you can see mountains. It’s amazing
Thank you for these amazing videos! Can you make a video that includes all of the affected areas in North Carolina- kind of like a quick summary- overview?
Phillip,
I've enjoyed your videos. Thanks for the education.
You said that landslides are a concern at any time that heavy rains fall. It made me wonder whether my house is at risk. We sit at the base of a couple of streams that fall from the mountains in Pisgah Forest. I wonder whether you could give an opinion of the level of risk of a landslide in Pisgah Forest.
Just curious, have you tried looking at Google Earth? It's what he he's using in these videos. (Perhaps other software too, don't know).
@@IMSiegfried I've used the maps to view the valleys above me, but his videos show that the whole process must be started somewhere. As I understand it, there's usually a very steep area at the top where the landslide gets rolling. I'm at the bottom of a mountain. I'm just wondering whether there's anything above Pisgah Forest that looks like it might give way in heavy rainfall.
A first responder team leader would be confronted with an excruciatingly poignant dilemma, unparalleled in the realm of calamities. Does one, with full cognizance, imperil the lives of one’s own team by venturing into a grave and immediate danger, to rescue victims who, if they even survived, most assuredly suffered from grievous, life-threatening injuries inflicted by the initial surge of debris-whilst knowing that, at any moment, another such landslide is likely to descend, placing the entire team in jeopardy of the same fate, with little to no warning or chance to escape, all for another debris flow that may or may not happen, to rescue soul(s) who may or may not still be alive? Indeed an act of heroic valor, if in wartime would be deemed conspicuous gallantry meritorious of a congressional medal of honor.
Tony Garrison didn’t hesitate with the dilemma. After the first slide in Garren Creek he jumped into action to perform rescues. He had just pulled one woman free from the aftermath of the first slide when a second descended and carried him away.
His funeral is today.
Strongly suspect that the hill tracks can easily become start points because of the way that upside slopes are excavated and deposited on the lower side giving two potential extra sources of loading.
On the upside there will be drainage ditches which gather the rainfall (nominally to discharge it to the nearby stream/creek) but that gathered water will also add to the local soil saturation and cross slope pressures.
Then on the outer/lower side the extra deposits of the extracted upslope rubble will have increased the local downhill slope with a slightly less compacted material providing a now saturated source for the flow.
Flows have to start somewhere.
In one sense, the hill tracks could be seen as equivalent to a fire break when looking back up-hill. It's unclear if the net effect is worse, or that it's just easy to blame, though comparison with avalanche slope 'management' bears careful consideration.
This is all well-known. Ask anyone who works in the coal mining business in West Virginia. What shocks me is all the building in these flood zones and along the hillsides where debris flow occurs. There are ways to mitigate it. Visit any strip mine in southern West Virginia to find out.
Can you please do one specific to what happened to the green river? THANK YOU for producing these videos!
Finally, a highly intelligent human to listen to!! :)
There are a few articles on chemical weathering, clay formation etc for that area…
“The influence of climate and topography on rock-fragment abundance in modern fluival sands of the southern Blue Ridge Mountains, North Carolina”
Journal of Sedimentary Research, 1 March 1988
J. H. Grantham | M. A. Velbel
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“Rates and time scales of clay-mineral formation by weathering in saprolitic regoliths of the southern Appalachians from geochemical mass balance”
Jason R. Price; Michael A. Velbel; Lina C. Patino
GSA Bulletin, MAY 01, 2005
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“Geochemical mass balances and weathering rates in forested watersheds of the southern Blue Ridge II. Effects of botanical uptake terms”
Allan B. Taylor, Michael Anthony Velbel
Geoderma
Volume 51, Issues 1-4, November 1991, Pages 29-50