Pond Boss Forums POND CONSTRUCTION Selecting a site Unclog my culvert

I made a quick trip to the preserve to meet with the coop Electric guru, roll some more truck tires to a staging area, and unload some veg killer on a trail. While there, I encountered an annoying reality in the life of a culvert.
This culvert is 12" dia, 30' long, double wall/smooth core. It runs under the new drive. The area had a couple of substantial rain events since I was last there. It carries a reasonably small runoff area, but it is in the middle of heavy timber...this means big-time leaves and sticks. Yep, it was clogged at the intake side. All it takes is a couple of sticks and the leaves start backin' up to choke it off. These pics are AFTER I removed about a bushel of wet leaves from the opening.
THIS IS LOOING INTO THE UPSTREAM SIDE
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THIS IS LOOKING UPSTREAM AT THE WINDING RUNOFF CHANNEL (as it comes toward us); THE OPENING OF THE CULVERT IS BELOW THE RED FLAG, RUNNING UNDER THE DRIVEWAY TOWARD LOWER/LEFT
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I need some ideas about how to contain the area. I don't want a grate...it's just gonna load up like the stick-dam. I think I will have the entry area opened up a little and tidied up; I have a bunch of fist sized rocks that I can spread and fan out in front of the opening to create a non-erosive funnel. What else? My first thought is that you won't stop the leaves, but maybe the goal is to stop the sticks...? Maybe pound some epoxy coated vertical rebars in a semi-circle surrounding the entry funnel, about 6" O.C.? That may work to strain out the big stuff, but it creeps me as a "impaling hazard".

Tried unsightly brush piles yet?

I knew it...
there are times that you can be SOOOO predictable

Brettski:

Taking a different angle: Assume that there will be rain events which will overwhelm any culvert, especially with a leaf/branch debris source like your nice wooded watershed. Even DD's unsightly brush piles (if they work DD, that's beauty, not ugly) can be clogged and bypassed sometimes.

Plan part of the drive immediately over or near the culvert as an emergency spillway. I think most of your erosion will occur on the downhill side where water running over the driveway cuts throught the gravel or back under the roadbase. A concrete edge (or, more aesthetically pleasing, native rocks set in concrete) would likely help; an all concrete spillway would be better but of course is a lot more work and would require cement truck access (an edge would probably be possible to do using hand-mix concrete).

Brettski,

One thing I might suggest is to dig out an area immediately in front of the culvert. This will allow much more small stuff to flow through...kind of a settling area. From the picture, the angle of the culvert with respect to the ground is much too small...but pictures can be deceiving.

Nothin better than a few good beagles, a good double shotgun and a farm with plenty of those "unsightly?"
brush piles.

Brett, here's my thought. After the storm, the brushpiles and resulting debris collection can be removed. I have used chicken wire staked into the ground but think it looks worse and seems to wash out. Actually, what I call a brush pile is some broken branches and maybe a small cedar or oak tree in the runoff areas.

Mine have worked pretty well. Tons of leaves have been trapped by my successive piles. Of course, my place is heavy forest and brush, so unsightly is the norm. My runoff areas are so thick that I can hardly walk through it. There's not much way I could clean it up and wouldn't really want to. Nothing manicured there.

Probably should have had a vernal pond dug in front of it.

How about a floating boom with a skirt of plastic cage material? I do this on a small scale for my small outlets consisting of 1 1/2 inch PVC which floats due to being capped at each end. Using a couple PVC elbows I make a 'U' shape boom and skirt in front of the outflow. Any floating debris etc. gets trapped against the boom and won't go into the overflow. I primarily do this to keep floating filamentous algae from clogging up my overflows.

Lance, what in the dickens is a vernal pond?

A small, shallow, intermittently flooded wetland, generally dry for most of the summer and fall. Vernal ponds provide critical habitat for breeding amphibians, and are also important for certain invertebrates and plants.
definition from www.dnr.state.wi.us/org/land/er/publications/cw/Glossary.asp

Sounds like an ideal location for temporary waterhole.

Lance, I have a bunch of those. I generally toss in some small bluegills for mosquito control.

Pardon my absence, but making a living beckoned.
ML: you bet, the entrance has to be opened up. This drive and culvert was installed last fall; I wanted to watch it for awhile to identify issues, anticipated and not.
Theo: when I inspected the lowest portion of the drive where the backed up water might have washed over, I found no evidence...guessing it never quite got that high. I do expect that it would, tho, given a gully-washer. This is the 2000 ft drive I created with 1200+ tons of heavy rock/gravel/clay mix. It is extremely stable and packed after running the train of 80,000# loaded trucks over it. It should weather an infrequent overwash well, but I am on board with the back edge protection as it rolls back off the driveway. The cost and work involved to do the wall might get trumped by unsightly brush piles (Dave can also be soooo insightful )
CB1: cool engineering, but I think it might be less effective without the "vernal pond" in place (btw, Lance...is this any relation to the vernal equinox?)
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All good help and input...thanx. At this point, beside cleaning up the entrance side and laying a rock bed to minimize erosion, I flipped the Magic 8 Ball and it replied: "Answer fuzzy, maybe brush piles...?"

Whatever gets the coon.

Brettski, The easiest way I know how to clean a clogged culvert is to cut a circle out of ¾ plywood 1” smaller than the culvert size and attach a chain to the center of the circle of the plywood circle. Then pull the chain and plywood circle through the culvert with a pickup or tractor. It will clean all the leaves and dirt build up out.

Culvert dilemna update; experiment #1.
I had a bunch of #3 rebar (3/8" dia) bent into hairpins about 24" long. The legs of the hairpins are about 3" apart. I pounded them in, spaced about 3" apart.


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the theory borrows from the simplistic genius of Dave's unsightly brush piles, only made of steel (soon to be rusty). We'll see if they start to collect the leaves after the first gulley washer rain...should work good for sticks and twigs.

Applications to join the Liberty Nature Preserve Wicked Wicket Croquet League should be sent to Brettski's E-Mail address.

...it's a very small course, but challenging

Brettski,

Any updates? Did it work?

Sure looks like a good solution and I'm very interested in your results.

Eddie

Dunno, yet. The leaves are still fallin', tho I bet 90% of 'em are down. I haven't had the much anticipated and hoped for gulley washer yet.
This culvert was put in about 14 months ago, late Summer '05. I didn't discover the leaf-plug until early this last Spring...I wasn't really watching. Over the Winter, I spend less weekends there when it's 20 degrees with 8" of snow.
I watch the weather alot closer now, ya know? I'll likely have a better handle on it when it gets tested. You betcha I'll check back.

You have snow? I didn't think about that. It's 60 degress out and the fall colors are amazing here. LOL

Eddie

We don't have snow yet....yet. But that doesn't mean I don't have the right to react to your insensitive sneer about living in a warmer climate. Hrrrmmmph!
(is that the correct number of Mad's Burgermeister?)

Ski, you can have your own insensitive sneer next August. Heck, I haven't even brought in my dwarf banana trees. BTW, it does snow here. Dang near every year. Also, for the last 8 years, we haven't clogged a whole lot of culverts.

You will note that Eddie has had to either adapt or evolve by eliminating his top layer of insulation. Me too.

Brettski, snow would look lovely on your croquet course.

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