Saturday, September 17, 2011

I thought this might happen....


Big storm overnight....  1.38" of rain fell in one hour starting about 2:30AM.  The storm tracked north right through one of the watersheds that feeds my pond.  Went out at daylight and saw the high water mark but no water way north of the dam.  Oops.  Looks like it slowly blew out each side of the dam and drained out.  Still have 8' of water in the pond but most of the dam is gone now.  Water was still running into the pond NW of the dam 12 hours after it stopped raining.  My contractor is coming out when the roads dry to assess the damage and to talk about a scaled down repair.  Think I will just have to settle on small pond instead of a lake.  Just wish there was light to get a photo of the full fill before the failure.  GoogleEarth image shows just how much water was backed up before the blowout based on what I saw this morning.  Since this was an experiment, I was mentally prepared for this eventuality so I'm not entirely surprised, only mildly disappointed and rather amazed at the power of nature.  Nothing ventured - nothing gained.  78,94,63, 1.38",B 

15 comments:

Al said...

That's why I asked about the spillway back when. When it rains some times it pours. You need a low area for water to spill over the dam with erosion protection so it doesn't destroy the dam when overtopped. Perhaps covered with non woven filter cloth and covered with rip rap to direct the water away from the toe of the dam. Alternatively if the dam was high enough and depending on topography you could direct excess water over existing natural rock. Sorry.

Best of luck.

Al

tffnguy said...

BUMMER! I expected it sooner or later to, but thought it would be later.

George said...

Sorry 'bout losing the lake; it was a great swimming hole. Yeah, water from heavy rains in the desert wreaks havoc. We nearly lost all of our mile long road in NM in a recent rain event - the "River Ran Through It". I hope you find it feasible to give it a good repair, with improvements (as it is with everything else you write about).

Al said...

One thing you can do using the internet is figure out how big the watershed is that feeds storm water to that sucker before trying to rebuild. Multiply the surface area by an inch or two of rain and you may be blown away, no pun intended.

Al

Don Auderer said...

Sorry to hear about the dam dam..
We got heavy rains in Alpine area again today.
Headed for dry East Texas tomorrow where we are still having fires.

Don Auderer said...
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Larry Prater said...

Bummer, I liked the ducks. Of course this is easy for me to say and not so easy for you to do, but I wish you could take Al's suggestion about a spillway so you could still have a larger pond or small lake. Benita would like that, I think.

tilapiacultmanifesto said...
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Al said...

Here's a useful reference.

http://www.weather.gov/oh/hdsc/PF_documents/TechnicalPaper_No40.pdf

Look at the 25 and 100 yr 24 hr storms. A predicted 4% and 1% chance of occurring in any given year. TP-40 has pretty much stood the test of time so far.

Water good. Water in the desert wonderful! Lots of water in the desert, watch out!

Al

tilapiacultmanifesto said...
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tilapiacultmanifesto said...
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Mary Lee said...

What about a rock collection? Every visitor needs to bring a rock...the larger the better to shore up the first dam and to make a smaller dam down-stream from the future spillway to collect water for the wildlife. Just a thought.

Allen Hare said...

Sad about the loss of the lake. Ok Hwa and I were going to bring our swim suits next trip. It was a good engineering experiment. I like your attitude about the whole affair. Best of luck with future projects.

2 Dogs said...

I guess the Spirit left that lake.

You need a spillway JW.

Al said...

Mary Lee appears to be the brightest among us. Will the topography allow re-construction of a pond that will it fill under low-flow conditions then allow higher flows to by pass using natural topography?

Al