Questions and answers from the GMA Techline
Fish pond lining
We have a project fixing an HDPE liner for a fish pond. Should we use HDPE liner 0.50mm? What would be the suitable covering sheet to protect the pond from UV?
(Mustafa | Saudi Arabia)
You ask good questions but ones that really require a knowledgeable consultant to answer on a site-specific basis so as to cover all of the details that might apply. That said, I can say that 0.50mm is simply too thin to reliably field weld using thermal methods (hot wedge or extrusion fillet). The minimum I would recommend is 1.0mm for not only welding but short-term and long-term survivability as well. Cover geomembranes (and I assume you mean floating covers) can be made from different resins (e.g., PE, PP, CSPE, EPDM, etc.) and they are usually scrim-reinforced. This means that there is a fabric between two plies of the membrane.
You should look at Geosynthetics magazine’s annual Specifier’s Guide to see what [geomembranes] are available in this regard.
Bob Koerner | GMA Techline