Hoodoos are tall, thin spires of rock that have usually eroded from the edge of a drainage basin. Hoodoos typically consist of relatively soft rock topped by harder, less easily eroded stone that protects each column from the elements. In the case of the Conroe hoodoos, the vegetation at the top of the pit helps provide that protection.
Of course, the hoodoos in Bryce Canyon formed over the last 40-60 million years, through the relentless forces of erosion. The Conroe hoodoos formed in the last two years. They’re not quite as spectacular or as tall. And they’re made out of sand, not sandstone.
Sandstone is formed when sand is cemented by such materials as silica and calcium carbonate. Most sandstones form through the accumulation of river sediments on seabeds. They are then compressed and uplifted to form new lands. Bryce Canyon was uplifted 8,000 feet, Conroe about two hundred.
Liberty Materials vs. Mother Nature
Here are some more pictures of the Liberty Materials mine in question.
And to give equal time to Mother Nature, here are some more pictures of Bryce Canyon.
Liberty looks a little sloppier than Mother Nature. But then, Mother Nature takes her time.
It may take a few more years before 2 million people a year start visiting the Liberty pit.
Posted by Bob Rehak
929 Days since Hurricane Harvey
Note: Unlike the other images on this site which are public domain, please refrain from copying or distributing my images of Bryce Canyon. To see more of my photography, visit BobRehak.com.
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/03/20200306-RJR_9337.jpg?fit=1200%2C800&ssl=18001200adminadmin2020-03-15 16:40:062020-03-15 16:59:47A Little Bit of Utah’s Bryce Canyon Comes to Conroe
To shine a light on the difference between the myth and reality, I’ve taken up a new hobby: sand-mine photography from a helicopter. On my December flight up the West Fork of the San Jacinto, I flew over this mine. Note the wetlands and utility corridor in the middle. Also note the trench leading through the trees on the right to that open gap in the tree line along the utility corridor.
I was curious about that gap. So I asked the pilot to go closer and got the photo below. How strange, I thought! The pipeline corridor has washed out, like at the Triple PG Mine. But this was a little different. The mine appeared to be draining the wetlands. Note the river of muck in the photo below.
Enlargement Shows Makeshift Supports
Someone had rigged “supports” under five pipelines. See the enlargement below. I put supports in quotes because they don’t seem to be working very well; note the sagging. Some look more like clotheslines than pipelines under pressure.
Pipelines Carry Highly Volatile Liquids
Investigation showed this is the SAME utility corridor bisecting the Triple PG mine miles to the southeast in Porter. These are the same five pipelines carrying highly volatile liquids (HVL). This mine, however, lies on the West Fork of the San Jacinto in Conroe near 242.
The channel under the five pipelines is up to a 100 feet wide.
Historical Images in Google Earth Show How This Happened
An investigation of historical satellite images in Google Earth shows that erosion has been a problem in this area at least since 1995 – the date of the earliest available image. Water overflowing the wetlands tried to make its way to the river on the other side of the utility corridor. The problem was manageable, however, as long as the land was flat. That was until 2014.
In 2014, two things happened. The mine started excavating right up to the edge of the pipelines (just as Triple PG did).
Next, three back-to-back-to-back monster storms in 2015, 2016 and 2017. They were “perfect storms” where the right combination of circumstances came together: Heavy rain. Exposed, loose soil. Steeper gradient.
How “Headward Erosion” Happens
The fact that miners had excavated up to the pipeline corridor with some very deep pits created a steep drop at the edge of the pipelines. That meant water crossing the corridor tended to accelerate and erode the sandy soil beneath the pipelines faster. The soil then sagged into the pit, much as you see in the pictures above. This process is well documented and has a name: headward erosion.
Here’s an illustration of how the process of headward erosion works
Trying to make the best of a bad situation, it appears that either the miners or the pipeliners tried to shore up their pipelines with supports. But it’s not working. They keep trying to plant grass. They keep using erosion control blankets. The supports keep sinking. And the pipelines keep sagging. Here’s an even bigger blowup.
It looks as if some of these supports are anchored in quicksand. Notice the extreme difference in their heights. The cross braces supporting the weight may be adjusted as the supports sink. But not on this day.
Another factor here: What if a tree washes down this chute during a torrential rain? It happens. Regularly.
I have a hard time imagining the stress on these pipelines. An engineer calculated a range of weights for me. He made some assumptions about the thickness of the pipes and the weight of liquids inside them. Then he calculated the weight of 100 feet. The range: 20,000 to 30,000 pounds. No wonder they’re sagging. That’s more than I weigh after a dinner at Carrabbas!
Probably No Imminent Danger, But Just in Case…
They’re probably not an imminent danger. But what happens in the next big storm? We’re overdue. It’s been more than two months!
Hundreds of thousands of gallons of flammable liquids. Under high-voltage electric lines. Pipes under stress. Erosion that widens with every storm. This should be a wake up call. But…
Posted by Bob Rehak on 12/9/2019 with help from Josh Alberson
832 Days after Hurricane Harvey and 80 since Imelda
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/12/Sagging-Pipelines.jpg?fit=1200%2C648&ssl=16481200adminadmin2019-12-08 21:45:292019-12-09 21:58:51Don’t Dig Near Pipelines: A TACA Safety Moment