On March 31, 2025, PFAS (perfluoroalkyl and polyfluoroalkyl substances) was identified in the Hōʻaeʻae Wells Granular Activated Carbon (GAC) Treatment Facility, which is part of the Waipahu ʻEwa Waiʻanae water system. This system provides water to the western area of O‘ahu, stretching from ʻEwa Beach to Mākaha, and includes Kapolei, Nānākuli, and Waiʻanae.
The Honolulu Board of Water Supply (BWS), which owns the facility, confirmed the presence of PFAS through a series of tests conducted between November 20, 2024, and February 14, 2025. The initial detection was communicated to the Hawaii Department of Health (DOH) via email on March 19, 2025. The detected PFAS levels included Perfluorohexanoic Acid (PFHxA) ranging from 2.0-2.2 ng/L and Perfluoropentanoic Acid (PFPeA) from 2.0-3.1 ng/L. Currently, the EPA has not established maximum contaminant levels (MCLs) for these substances.
PFAS are fluorinated organic chemicals that have been utilized since the 1940s in various industries and consumer products, such as waterproof and nonstick cookware, fire-fighting foam, and more. Although they are widespread in industrial applications, the EPA underscores the need for oversight due to potential health concerns.
For those seeking further information, resources are available at the EPA's website and the Hawaii Department of Health's PFAS page. The BWS also invites users to reach out directly. This notification complies with Hawaii Revised Statutes Section 340E-24(b).