Impermeable Layers for Best Management Practices 1

[EngWade]

Can anyone suggest some economical/feasible options for designing impermeable layers in Best Management Practices (e.g. stormwater detention ponds, or wetlands). I have a situation where I am designing a wet swale, in a site with rather sandy soils. For this situation it is necessary to prevent infiltration to the best that I can. Typically I've always spec'd to put in a layer of clay to act as the impermeable boundary, but wanted to see if anyone else has practiced other solutions to this.

Thanks in advance.

 

[beej67]

Your other obvious options are an impermeable geotextile fabric, or in more extreme circumstances a pvc landfill liner.

 

[ianlander]

I echo beej67, a Polyprop landfill liner would be best. Comes in large rolls and if joints are needed can be welded to form a continuous barrier.

 

[cvg]

I'm not sure a liner or fabric would be useful in a wet pond. Sure it would reduce infiltration, but it would block vegetative growth. Either one would limit vegetation growth which I must assume is an essential part of your wet swale BMP. Stick with the clay.