Drainage for wet area near the river

[yanmars]

I have an area about 150 feet wide and 600 feet long that stays pretty wet near the river. I have been able to have it mowed twice in drought conditions to get rid of junk shrubs, saplings etc. Even then the track equipment nearly got stuck a couple of times and certainly left large ruts. The top ground in the very soft areas is kind of a dark muck material.
There are perhaps a dozen larger trees in that area, nothing of real value, maybe one walnut and oak.
I would like to add some farm drainage tile so it might dry enough I could mow it with my own equipment without getting stuck. I can run the drains to the river.
One issue, would the remaining tree roots grow into the tile and make them useless. Also a lot of small stumps remain from the trees already removed, I do not think a ditching machine has a chance, I would think a track back hoe would need to do the work. Unsure of the expense and spacing of the tile to do an adequate job.
Any thoughts would be appreciated. With it "cleared" for the moment I can now see the river from the barn and deer and turkeys that I did not know were going through that area. Thanks

 

[jaxs]

Your question is directly about tiling the area but as TBNers are famous for I question your reasons for doing it. Nature needs diverse habitat and the type you describe is found most places. Unless you have pressing need for the 2 acres I'd say leave it be and don't spend time and money messing with Mother Nature.
Many years ago my brother got into a sideline raising hogs on the 800 acre row cropping family farm. There were 200 acres of woodland used as pastureland. There were 4 areas ranging from 1/2 acre to 5 acres that stayed wet year-round. One by one brother fenced them for hogs. Within a couple of years a pond appeared in each are and remainder dried up. Hog pens were torn down over 50 years ago and those ponds remain today draining to a nearby creek. I don't know if there would be repercussions about poluting the river but fencing your swamp for hogs and goats would cost far less than tiling and might result in conditions you are pleased with. If you wound up with a pond it would be simple to drain if it wasn't doing so naturally.
A similar approach if you have a tractor hoe is begin trenching from downhill edge piling dirt along side trench to keep tractor out of mud. Probably have to dig a while then let piled dirt dry before digging more.

 

[paulsharvey]

So, the tile would still have to be gravity fees down hill to the river. My thought, how much fall from this wet area to the mean high water line of the river? If you have less than 18", I dont think the tile stand a chance of surviving. If it Is 18" or more, I would look at possibly cutting some minor swales. Doesn't have to be extreme, if this is primarily a water issue. It could also be a muck/organics issue, which is much harder to deal with.

Also, make sure you're not going to cause yourself legal issues. Water rules vary wildly by state, but in Florida, I'm not sure this would be something you can just go and do.

 

[paulsharvey]

If the grades work for tile; as the ground water comes out of that mucky organic soil, the soil itself will subside too.

 

[paulsharvey]

If it was me, and I was allowed; I think I would consider digging 2 small ponds with a channel from the pond to the river, and then using the spoils to bring up the remaining grades. The extra weight of that fill will create what is called a Surcharge, basically additional weight, squeezes the water out of the soils, which will gather in the ponds, and then outfall to the river.

For the environmental minded, the outfall channels create the ability to clean the outfall waters though grasses/veg, removing turbidity and any nutrients from the outfalling water.

 

[yanmars]

If I get time I will try to measure how high the land is above the current water's top. It is really low now. Several times a year the river floods and overflows there, the rise then could be 7 or 8 feet for sure. Right now I "think" the bank top is 4 or 5 feet above the low water.
I thought of a grass "waterway" but do not think that will do much for me. I have 3/4 mile of river front, most of it floods at times up to 300 to 400 feet out of the banks. Just wanted to try to dry up a very limited area.
Years ago there was a road that followed the river but several bad floods washed out parts and it was abandoned maybe 100 years ago.

 

[2manyrocks]

I don't know and can't speak to any potential environmental issues that could arise, but part of me wonders if you could outfit a BCS walk behind with some kind of high flotation tires and cut this with a flail or brush mower? If you got stuck, it would be easier to winch out than a tractor.

 

[yanmars]

I do have a DR mower but enough small stumps etc that it has not worked well. I have a pull behind for my ATV but similar issues and of getting stuck. Not quite like jello the ground but pretty infirm.

 

[paulsharvey]

If I get time I will try to measure how high the land is above the current water's top. It is really low now. Several times a year the river floods and overflows there, the rise then could be 7 or 8 feet for sure. Right now I "think" the bank top is 4 or 5 feet above the low water.
I thought of a grass "waterway" but do not think that will do much for me. I have 3/4 mile of river front, most of it floods at times up to 300 to 400 feet out of the banks. Just wanted to try to dry up a very limited area.
Years ago there was a road that followed the river but several bad floods washed out parts and it was abandoned maybe 100 years ago.

So, I would probably cut some 12" deep x 24" wide ditches, running maybe 45 degrees from river main line of flow, to help get the water out of the boggy area, and keep water from sitting on it as bad/as long when water does come up.

I'm just not sure how tile will work, it might be fine, but it's gonna be a real pain in the butt to install.

Edit: obviously, angled toward the way the river is flowing. I think part of the way to deal with it, is to keep the water from just sitting there for weeks/months after a rise, and getting it out of there as soon as the main river starts dropping.

 

[bigtiller]

For every foot deep field tile is laid, it will drain 10 foot left and right of it.
so if you placed the tile 4 foot deep, you would need a line every 80 feet for good coverage.

Or you could trench a line on both sides of every problem area and hope for the best. The problem areas will always be soft without tile. So put in as much as you can afford and get a GPS map from the installer so more tile can be added in the future.

 

[paulsharvey]

For every foot deep field tile is laid, it will drain 10 foot left and right of it.
so if you placed the tile 4 foot deep, you would need a line every 80 feet for good coverage.

Or you could trench a line on both sides of every problem area and hope for the best.

Does tile work OK in a muck type soil?

 

[bigtiller]

Does tile work OK in a muck type soil?

Yes.
Muck drains better and shrinks less

 

[jaxs]

This sounds like a natural spring that surfaces where there's no slope in land for drainage. Is there possibly a berm,dam or hill that can be cut?

 

[paulsharvey]

This sounds like a natural spring that surfaces where there's no slope in land for drainage. Is there possibly a berm,dam or hill that can be cut?

My assumption was that it's a flood plain area, that has a lot of organics, and traps water for an extended period after flood stage, saturating the ground. you can't really do anything about the flood stage, really, but you can try to get the water off of it as quickly post flood as possible.

Around here, tile is only used for farm fields, and ditches/channels/swales are used for general drainage.

One thing the OP can do that will tell him/us a lot: take some post hole diggers down there and dig some test holes, maybe 3 ft down in the area, and see what the water table is. if the water table in the area is higher than the river, you can do something; if it's about the same, ditches aren't going to do anything but make a mess

 

[paulsharvey]

I should add, not that you asked (sorry); you mention the tree stumps/brush; being next to the river, this is what keeps that area from eroding (depending on shape/speed/volume of the river). You might need to keep some deeply rooted (or more likely, widely rooted) rougher veg in the area to prevent some pretty major erosion in floods.

 

[rScotty]

I would cut trenches and if you want to put drain tile into them that's fine...but leave them open until you get an idea of how they work. At least that is what I did. I got an area drained after several different ideas and tries, but in the process made every mistake possible.

After covering them, I have had a lot of problems with roots clogging mine. Mostly willow roots. Going to have to dig them up again. My advice is to make an access point every 75 feet for rooting them out.
Start now & budget for a roto rooter. We bought one... should have used heavier tile and bought a heavier rooter too. Like I said, every mistake.... we have about a quarter mile of creek frontage, so in that way the projects are similar.

Surprising how little slope is required on the drains. Get a slope gauge, a 2% slope is plenty. The trick is to make the slope so that the water can push any dirt through without leaving mud build up in the drain tile. Too much slope and the water outruns the dirt.

rScotty

 

[bigtiller]

Field tile doesn't need a lot of fall. The crew I worked on set some of it 0.1 percent grade on flat ground. That is equal to 1 foot of fall per 1,000 feet, but that takes a pretty good laser or gps.

 

[paulsharvey]

In theory, there shouldn't be any sediment in the tile, unless something was gone wrong.

 

[rScotty]

In theory, there shouldn't be any sediment in the tile, unless something was gone wrong.

Right. And what keeps ithe pipe clean is getting the slope right. I like to start with a drop of about one percent. That's one foot of drop in 100 feet of run....which is sort of hard to measure, but turns out to be about 1/8" drop per foot - but I found that also hard to measure.

Watching the water run as I ws digging the ditch with the backhoe got the slope close to right. What I did to get the pipe sloped right was to buy a four foot slope level. From Kapro on Amazon. About $50. It has a series of vials set along the top and each one is a different percent of slope. That level made sloping the pipe easy.

Kapro - 105 Topgrade Gradient Box Level - with Slope Measurements​

 

[bcp]

Extreme accuracy isn't required.

A 48 inch level with a 1/2 inch spacer glued/taped to one end is close to 1%.

For a longer level, find a straight 1x2 75 inches long, on edge, with a 3/4 inch spacer on the end, and a short level taped to the center. Or 8ft with 1in spacer.

Bruce