As far as hardwoods over the trench, if you can get some Osage Orange corner posts (we locally call them "hedge posts") they will last 30-40 years as a corner post so submerged I would imagine they would last for as long as the pond had life.
Don't know if they are available in your area. Many years ago lots were cut from the "hedge rows" that were originally used as fence lines from this area and shipped south for both line posts as well as the larger ones for corner posts. They are still used locally for corner posts but most everyone uses steel posts for line posts. I cut from our own hedge rows the ones used in my dock for dock pilings. Also used some old line posts we had taken out of a fence that were already 30+ years old (and still good) to crib up and add boards for FHM spawning and cover for small BG.
In our new pond we have a deep area near the dam then another deep area closer to the opposite side where we excavated with a scraper to get the rest of the dirt for the dam. So the center of our pond is actually shallower than either side. Then in this shallow center area we took the scraper and cut trenches laterally across the pond in about four places. We bridged all the way across in some places and slanted to the bottom in other places structure. Used a variety of things, one being a large Osage Orange stump we removed from near the site turned on its side and weighted down with concrete foundation pieces. The root ball was so large actually had to cut some of it off so it would not be above water (in about a 9' depth area). Another thing we made a lot of use of was concrete foundation pieces we got from our defunct turkey growing operation. The concrete foundations were about a foot thick by two feet wide by anything from six foot to 12 foot in length (whatever broke off when the dozer pushed it out). These concrete chunks ought to last long enough. We also "cribbed" a bunch of them with wild cedar trees standing upright within. Recently I have learned the cedar will go away in a few years so wish I would have added some plastic or other finer material along with the cedars. Oh well, I'm a scuba diver so will be able to inspect and maybe add as needed. Also used some salvaged concrete "slabs" from the same source and made overhang ledges in a few places along drop offs to replicate a "bluff". Maybe someone nearby tearing out some foundations that they might have to pay to dispose of you could get for free?
Just some ideas for you. If you have access to Osage Orange trees or concrete foundation pieces or slabs, they both last a long time.
Last edited by snrub; 11/25/13 01:01 AM.
