EPDM pond liners are extremely flexible and remain so even in extreme temperatures. Their molecular structure means they can easily stretch and return to their original shape without deformation. This quality makes them naturally resistant to tears. While exposure to sunlight will weaken many types of pond liners, EPDM is naturally resistant to UV degradation and will maintain its flexibility.
While EPDM can be punctured, its ability to flex helps protect against that risk, and pond liners are typically relatively thick (45mil or more), which helps the material withstand puncture damage. Of course, it's important to always install a nonwoven geotextile underlayment to protect your liner for the long haul.