There are lots of types of liners available, but California has some special regulations in place governing what you can use, plus some liner types are better than others. Let’s start with Proposition 65. This regulation requires the disclosure of chemicals and other ingredients within a product that may have a chance to cause cancer. All products sold in California must have a label that discloses any of the hundreds of ingredients listed in Proposition 65’s provisions. While this law was initially not designed with pond liners in mind, legal precedents set since the law’s inception means that Proposition 65 warnings should be on these products, too. Thus, when purchasing a pond liner, you’ll need to make sure that it carries the warning label required by these regulations.
Now, as to materials, some just perform better than others—especially in the Californian climate. Asphalt and concrete can be used, but California’s warm temperatures, sunshine, and wind all lead to water loss through evaporation. Asphalt and concrete both compound water loss due to seepage through the porous material. The same is true of clay liners. Liners where seepage isn’t a problem are the best bet, and that leaves materials like reinforced polyethylene, high density polyethylene, low density polyethylene, EPDM, and polyvinyl chloride. Of these, reinforced polyethylene (RPE) liners like those we sell here at BTL Liner are the best bet. They’re thinner and lighter than other options, but are more resistant against tears and punctures. Another crucial factor is that RPE is more resistant to UV rays than other materials, which makes these liners better able to withstand California sunshine as opposed to, for example, PVC liners that degrade rather quickly under UV exposure.
