I didnt take enugh pictures this summer but I will post some of them from our largest summer prodject. This is a pond {flood control structure} that will have 29 acres of water at normal pool and 65 acres at emergency spillway. It has 1400 acres of drainage above it.
More Pictures The rcp pipe was a new experience for us but it went way better than expected. The worst part was the outlet support that had to be precast at the shop then set in place the bottom of it was 8 feet below the stream and the material was less than sutible, I would call it quicksand, but we got through it. The plunge pool was 7 feet deep and 40 foot square at the top and was full of water the morning after we finished it. The pond will be 20 foot deep at the deepest spot but there will be close to 10 acres that are 15 feet deep.
WOW!!! That is some "POND"!!! Around my area that is more like a "lake", compared to the "ponds" we have around my area of north central Missouri! I'm curious who paid for it??? Since you say it's a "flood control" pond, did the County, or some such entity foot the bill, or did the farmer? I'm SURE that cost a "pretty penny"! More like a few TRILLION pennies, I imagine! Great work though, it sure looks like a "professional" job for sure! GREAT pics, thanks for sharing them! JD
The pond was funded through the fedral goverment there are 135 of thim in a 3 county area they had plans to build 25 more but they cut funding and this is one of the last few to be built unless they refund but I dont see that happening any time soon. I hate to loose the opportunity for big prodjects close to home but they need to stop spending somewere. These ponds dont cost the landowner a penny they just increase the value to there property and they usualy put in crossings and replace all the fence around the area were we work. This is one of the largest ponds they have built they are usualy 3 to 5 acres.
Thanks for the info Cowman, that's pretty cool that the farmer didn't have to foot the bill, and it's ALWAYS great to see when a farmer actually gets SOME KIND of "spiff" after all they do for everyone, and have a hard enough time just making ends meet themselves!!! I hope they will fund more of them, but I must agree, with how VERY POORLY things are looking, I don't see that happening any time soon either! Thanks for sharing all that with us, I found it VERY interesting, and just fun to look at as well! Best regards, JD
Thanks Cowman, really interesting stuff, and assuming this will dissipate the size of flood damage downstream, provide a source of irrigation water and even a place to thrash jetskis on. Kind of like beavers but on a larger scale. Should be more of it done once you guys have finished in Afghanistan. Good to see common sense infrastructure projects like this keeping operators in meaningful work.
That's incredible! What does the big pipe do and what is a plunge pool?
The Big pipe lets the water from the pond back in to the stream after the pond is full. The plunge pool gives the water comeing out of the big pipe a place to slow down so it does not erode the stram chanel. They usualy use steel pipe or coragated galvanized pipe but this pond had enugh stage above the pipe and head preasure it called for concrete pipe or so the engineer said.
The house on the hill sure will have an awesome view when the pond fills up.
it shure will, it is going to be a bed and breakfest. there are 2 small ponds right beside the house that we built while we were there.
Nice job fer sure! I think gramps will appreciate the new fishing hole!:falldownlaugh:falldownlaugh
SE-Ia Cowman, We're lime stabilizing one of these government dams in Central TX that's had a slope slide. We're replacing 40' of the RCP/steel outlet tube. On the last section of pipe, the slope is 0%. What did you use for blocks or shims to adjust your slope on your last section of pipe?
wow thats hugh i hope the grandkids like to fish
Yair...Just curious SE-Ia Cowman. I assume the concrete pipe is just for low flow and the main spillway is at the far end of the bank...it's a bit hard to tell from the pictures. Cheers.
SE-Ia Cowman, How do you fill in and compact material under that pipe to make sure that area can't leak through underneath the pipe?
Yair...Tracklayer. Seems the Cowman is off-line or doesn't want to talk. Real good point you raise about compaction around pipe...and pretty much why I refuse to do those type of installations. The few I have seen were initialy hand compacted with a whacker or some such. I think the most important part of through bank pipes are the baffles that are welded onto steel pipe or (presumably) cast onto concrete...essentialy they are just a ring extending a couple of feet out from the pipe to help prevent the migration of water along the outer surface. It's all a pain in the butt and I have yet to see an installation where it is really needed. From the above photo's it appears the pipe will not take the volume of water coming down that gully and the dam will need a proper by-wash and spillway so why mess around and compromise the integrity of the bank with a pipe? As I have mentioned on other posts if water is needed on the downstream side of the bank it is a simple and elegant thing to arrange a syphon. They can be floating or fixed and the biggest I have done was a ten incher which flowed a lot of water. Cheers
Scrub Puller, I see what you are saying about the pipe making a seal right where it goes into the bank. From the pictures, I am not sure if I fully understand the design of that dam and spill pipe. On the outlet end, the pipe looks like it is very deep into the dam. But I assume that it would be near the top at the inlet end. I think I would be inclined to want it near the surface of the dam for the whole run. Maybe even have it daylighted in an open concrete trough partly filled with riprap rock to slow down the water. I’m not saying that it is done incorrectly, but just curious about the design.
On these government dams, they're only built for flood control and silt sedimentation. The one we're working on is 21 acres at primary spillway (the drawdown tube shown in pics) and 52 acres at auxillary spillway (earthen spillway) that has 4 feet of freeboard between them. There are anti-seep collars welded onto the pipe in the core of the dam to keep water from running along side the pipe. They want them to fill up and take a good while to draw down to prevent downstream flooding and erosion. When these lakes fill in with sediment after 100 years or so, they will go downstream and build a new one. Not near as common now since it's not farmed fencerow to fencerow.
Yair...gotcha d9gdon. The concrete pipe is low flow as I mentioned in post #14 upthread...in other words in a big rain event when the dam fills the water rises four feet above pipe level and then bywashes across the spillway. The pipe then syphons off that top four feet over an extended period...works for me...but why do they put the pipe low down in the bank? Is this maybe to suck the silt out? Cheers.
Scrub Puller, The pipe is low in the downstream side of the dam to prevent erosion in the channel where it exits. We have to build a plunge basin lined with rip rap to slow the water where it comes out the pipe. There is a baffle plate in the riser where you can adjust the pipe flow. They usually rust and the adjustment wheel becomes useless. The pipe on the upstream side is about 8 feet higher than the discharge side.
Sorry for the delay guys with winter shut down i have been out of the dirt work mood and in to mechanic mood. First question compaction under the pipe. the pipe was set on ground that met +95% compaction then we poured concrete under the pipe hence the blocks and wedges to keep at least .5' for concrete to flow under and around the pipe, forms were 12'' tall then we poured the mud stiff enough to push up aginst the pipe halfway up. Hard to put in to words but the whole lower half and .5' under the pipe is bedded with concrete. Then we used a jumping jack and packed the top half we had to have 2' covering the pipe before we could cross it with a sheeps foot. In sted of anti seep collors the use a sand diaphram it crosses the pipe in the middle of the dam 3'wide 15'long goes from 6' below pipe to 12' above the pipe then runs parallel with the pipe about 6' to the side down to the outlet channel. The engineers think if the water ever tunnels along side of the pipe it will filter down through the sand at the half way point and have a controlled path to the outlet and not wash out the dam. Yes scrub the pipe is for normal rain water the emergency spillway has a 4% inlet section a 30' wide by 72' long control section and the rest is 2% outlet section. It is along the far end of the dam. With 12' of stage between the pipe and the emergency this pond will likely not see any emergency water for many years, engineer says 100 year flood but around here we have one of them every other year.
Just reading more and Scrubs the pipe realy isnt that low in the bank there is a lot of dam above the pipe for more storage and longer draw down period for as you stated flood control. the 12' feet of freeboard from pipe to emergency spillway doubles the acrage of the pond and that is a volume increase of 4x what it holds at normal pool. Lets just say it takes a 10'' rain to fill the pond after it was finished then it should take 40'' to get from the pipe to the emergency spillway. these numbers are not realistic but makes for a good example. As for the instalation we put the pipe in to there exact specs. But the goverment proably spent twice what it cost to build the pond in designing it so it probably is not going to work if it is like anything else our goverment does these days.
Also the upper end of the pipe had a concrete pad poured around it 12' wide by 12' long then we poured 12' wide on the slope above the pipe up about 6' in elavation. this should keep the swirrling around the pipe from washing any.
SE-Ia Cowman, Thanks for that explanation about supporting the pipe. I had wondered about the possibility of an approach that would grout under the pipe once it was blocked up like you show. It sounds like that is exactly what you did. It sounds like a very well engineered project.
Just looking at the pipes sitting on blocks, how do you compact the material under the pipe, or is it filled with concrete? also noticed the bucket on while lifting pipes, they would shoot u for that over here. Cheers RDG.