Help installing a rock drainage channel

RLWATSO1 · Apr 14, 2017

Installed a new driveway to our home build site. Drive held up well during a recent hard rain (2 inches of rain in 12 hrs) but I need to install some rock drainage channels. I'm not an excavator by any means so I need some advice.

My plan was to lay landscaping fabric down then put a layer of 57's then put large rip rap type stuff or large cobble (6-12in or so) on top... is this a decent solution? The first area has decent incline so I'm a little worried the smaller rock will get carried away into the culverts.

Thanks for any suggestions!

Spot 1:

Spot 2:

boggen · Apr 14, 2017

google keyword search = forestry road
A Landowner's Guide to Building Forest Access Roads - Introduction
Forest Road BMPs

google keyword search = erosion ditch rock

also look at "french drain" setups. ditch + pipe + fabric + rock

above is more about trying to get you pictures you can see more so if you click up on "images" after you searched. so you can see what others have done. might suggest adding on DIY to the search terms.

you also can install field tile / drainage piping within the hill. there are some issues in how it is installed UP/down the hill vs across the hill and how it all gets hooked together. there be pro's con's to each one. and some NO NO's mixed in that can cause additional erosion issues.

Streetcar · Apr 14, 2017

Skip the 57s, they will be washed away with any significant rain.
The geotextile will help keep weeds out of rip rap

RedNeckRacin · Apr 14, 2017

Agreed, skip the 57's, the rip rap is what you want to make an energy reducing apron. If you have concentrated flow, you need to use bigger stone to keep them in place and protect the channel lining. There are several resources for sizing stone for this if you want to look at them.

Egon · Apr 14, 2017

Make a wide gentle sloped swale. In the center a slightly deeper trench filled with larger pit run type rocks that allow water to flow between them. Straw bales can be layed across the swale to slow down the drain water.

Fabric really wil not help much. Water will flow underneath it and dirt/dust gets on top of it for weeds to grow in.

bcp · Apr 14, 2017

Several years ago the county lined a steep roadside ditch with rock. It's overgrown now, but seems fully intact, and we get LOTS of rain here. I would guess it is around 3-4 feet wide and a foot to 18in deep.

As best I could tell with several drive-bys, they shaped the dirt, then hand-placed about 6-8 inch rocks, and pressed them into place with the back of a backhoe bucket.

Bruce

Dadnatron · Apr 14, 2017

Avoid a 'V' shape and maintain a consistent grade if at all possible. Your best bet is to keep the water running as a 'sheet' rather than a stream. I would not use the fabric. It isn't going to help you with anything. If you have water running at any significant rate, it will pass through the fabric and run underneathe, scouring the dirt below. Rip rap carefully placed and as wide and shallow of a run as possible will do you well.

The amount of runoff is MUCH more than it will be when you have grass growing on the surround cleared dirt. Let the grass do its job and I suspect you won't have much of an issue. I don't see any significant erosion in the pasture above this location. It is very difficult to visualize grade on pictures though.

RedNeckRacin · Apr 14, 2017

Straw bales are less than worthless. All they do is back up the water and cause the backed up water to flow around or undermine them and create more erosion.