Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Rebuilding a broken Pond- Input wanted

Hello All,

This is awesome, a forum and user community dedicated to private pond construction and maintenance! I wanted to first thank the experts here for time and consideration of the issue I am about to post.
My family and I recently purchased a piece of property east of San Antonio Texas, very near the Cibolo creek watershed. This property has an existing pond site on it that appears to have had the dam defeated in the flood that occurred in 2002. I am currently working to clear out the pond site, banks and drainage areas (so that I can re-plant them with good grasses to cut the erosion).
The dam itself was completely defeated and was almost removed entirely by the last flood (see pictures). At this point I am just reaching out to the Texas NRCC folks for assistance/planning on the dam reconstruction effort. I have access to dozer (D4) and a large 5yd komatsu wheel loader, as well as a vibra-compactor. I have read up on the usda soil conservation service pond construction handbook, and have a good idea of the basics, but would like to ask for some expert advice. At this point my plan is to continue digging out the pond itself, using quality clay from that excavation to form the dam core, later finishing with dirt taken from the pond- in 6" lifts while compacting. Here are some pictures for reference:

*Aerial View*

http://c1538982.cdn.cloudfiles.rackspacecloud.com/3.JPG


*Location with natural drainage*

http://c1538982.cdn.cloudfiles.rackspacecloud.com/pond3.JPG

*Ground Level*

http://c1538982.cdn.cloudfiles.rackspacecloud.com/IMG_2300.JPG

*Spillway in front of Dam*

http://c1538982.cdn.cloudfiles.rackspacecloud.com/IMG_2301.JPG


*Looking down where dam was 'cut'*

http://c1538982.cdn.cloudfiles.rackspacecloud.com/IMG_2302.JPG

*Standing where front of dam would be (fence ran across top of dam*

http://c1538982.cdn.cloudfiles.rackspacecloud.com/IMG_2303.JPG

I also did a video walk-through since I figured that might be easier to 'visualize'. That video can be seen here:
http://www.youtube.com/watch?v=5W3EHtftHOg

As mentioned-just getting going here, got a rough game plan but would appreciate some feedback / educated opinions. Recommendations in the form of 'this is what I would do Jeremy' are welcome!

Thanks in advance everyone! I am looking to get this knocked out soon, so if you are a contractor/consultant near the SA area, lets talk.

-Jeremy

Jeremy you appear to be on the right path. The soil looks good to repair the dam. I can see from the size of the primary spillway this pond location appears to have a large watershed. The flood event in 2002 with over 30 inches of rain fall was probably way bigger than any spillway has ever been designed to handle. My only input is you should concentrate on making the emergency spillway bigger. As big as the topo and $ will allow. Most likely the primary spillway is designed to carry most runoff events judging from its size. The only thing I saw in the video that would concern me is the slope of the emergency spillway on the back side. If it gets used to often it to could wash out. The NRCS guy should be able to determine if the original Dam and spillways were adequately sized. Going to be real nice when you getter patched up. Check out this thread each time I see it I kick my behind for not doing it like this. The entire project is incredable to say the least but check out the diving platform made of rock they built while constructing the lake. I sure wish I would have done that when we constructed our ponds.

http://www.pondboss.com/forums/ubbthreads.php?ubb=showflat&Number=168590&page=1

yes that is what i meant by shrinkage. the standard i use is 10% using a dozer,5% using my scraper if its dry i go more i usually overkill especially on the bigger ponds. i wanted to say a lot more but cant type worth a flip. for example if that spot needs 15' of fill to reach top of dam elevation using a dozer i would put 1.5' of extra dirt on top for shrinkage using my scraper i would put 7.5'' extra on there. if i was rebuilding that pond the first thing i would do is get my top of dam elevation lets call it 100, then i'd check my emergency spillway elevation if its just on one side its maybe 97 or 3' lower than top, then i'd check my pipe inlet its maybe 95 or 5' lower than top. this would give you 5' of freeboard or 5' of water control before it goes over dam.like i said it washed this particular spot out for a reason. it would be interesting to know if the top of dam elevation starts getting lower from the sides to the middle so i'd take some readings every 25' on top of dam to see if it varies more than 2 inches below your desired top of dam elevation. i would want to know every thing about this dam that i could find out easily then i'd go to work on it. i'm also a topsoil nut i'd find some to cap that clay off when done it really cuts down on erosion and just looks better. i'd also show my nrcs guy what all them elevations are and have him figure drainage. they dont charge me for that here and they can do it quickly from their office here. p.s. i really admire that clay where i am i usually have to bust through rock to get to shale or clay i had to go 6' deep on a core yesterday then scrounge around for clay to put back in it. i hope this helps u some if older fellows wouldnt have helped me i wouldnt be much now just hopin to dish out some of what they gave me.