Grass Swale

[Vinny7]

This is also posted on the storm/flood forum as i was unsure which would be the best location.

Can anyone give me guidance on the construction, layout etc. for a grassed swale for stormwater run-off from a small hard standing?

A typical detail would be great is anyone knows where i could get one.

Thanks
Vinny

 

[GoldDredger]

In my experience, little grass swales don't get any special consideration for design. I would try to give it a 2% slope with a FG spot shot here and there, then let the landscaper lay the sod.

If you are worried that is not enough, and your swale will erode, there are a number of 'armoring' solutions you can consider. There are a ton of erosion type mats, both degradable and permanent, which allow for grass to grow through them, making them invisible over time. Some are strong enough for traffic, others strictly to prevent erosion.

Or you could even go with a landscape type drain. A little 4" pvc pipe or something.

You might try

http://www.maccaferri-usa.com

or

http://www.invisiblestructures.com

 

[ACtrafficengr]

Here are the NYS Dept. of Environmental Conservation's specifications for grassed swales:

http://www.dec.ny.gov/docs/water_pdf/sec5bperm3.pdf

You could also check with your state's stormwater regulating agency.



"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

[bank]

The attached EPA document discusses the function and design requirements for grass swales as a storm water quality BMP. Additional guidance can be obtained from Prince George's County, Maryland, and State of Virginia Low Impact Development/Storm Water Quality Management literature.