---
url: https://www.eurocovers.eu/glossary/hdpe
term: HDPE (high-density polyethylene)
definition: An engineering thermoplastic widely used in industrial water infrastructure for UV resistance, chemical compatibility, freeze-thaw tolerance, and NSF-61 potable water certification.
updated: 2026-05-25
---

# HDPE (high-density polyethylene)

An engineering thermoplastic widely used in industrial water infrastructure for UV resistance, chemical compatibility, freeze-thaw tolerance, and NSF-61 potable water certification.

**HDPE** (high-density polyethylene) is the polymer used in modern floating cover elements. It is
chosen for its long-term UV resistance, freeze-thaw tolerance, chemical compatibility with most
industrial water chemistries, and the availability of NSF-61 certified grades for potable water
applications. HDPE is recyclable at end-of-life through standard polyethylene recovery streams,
supporting circular-economy reporting for ESG-disclosing operators.

In the AWTT-patented hexagonal cover (see [/heritage](/heritage)), HDPE is moulded into
self-ballasting hexagonal elements with a raised central dome — a geometry validated through
hurricane testing and 18+ years of field deployment.