From the GMA Techline
Question on the Geosynthetics magazine article: “Pipeless drainage system” (April 2008)
What is the most used design method for drainage systems in MSEW with geosynthetics? Or what can I do for designing a system for drainage in the MSEW?
Reply: The question is what type of drainage system is most common. I think that a sand or gravel layer with an embedded perforated pipe system is the most common on a historical basis. I say this because that is how the U.S. EPA’s guidelines were originally crafted. The change over the recent 10 years is to use a geonet composite directly on the geomembrane with the sand or gravel over it—i.e., no pipe system at all.
For both of these strategies, the design will control in many cases. This design uses the HELP computer code that was developed for the EPA and is now used worldwide for the design of leachate collection and removal systems. Hope this helps.