Hundreds of eels and fish were found dead over the weekend in Campbells Bay Creek, a North Shore waterway in Auckland that volunteers have spent decades restoring. The mass die-off is believed to have been caused by a chemical spill into the stream, which flows into the broader ecosystem and ultimately leads to the sea.

Richard Hursthouse, chair of the Campbells Bay Urban Sanctuary, described the event as “truly gutting” and suggested that the contaminant was likely an industrial chemical such as a cleaner or paint, possibly originating from a nearby development site. He highlighted the connection between stormwater drains and local waterways, noting that substances dumped into stormwater systems can travel considerable distances downstream.

Over the past three months alone, volunteers have dedicated approximately 1,000 hours and significant financial resources to maintaining the health of Campbells Bay Creek. Efforts have included planting, weeding, and monitoring water quality indicators such as pH levels to detect pollution, especially from alkaline substances. Common pollutants previously identified include silt, plaster, cement, and paint.

Viv Walker, catchment adviser for Restore Hibiscus and Bays, stressed the vulnerability of the creek’s ecosystem and noted that 89% of New Zealand’s native freshwater species are under threat or at risk of extinction. The incident has raised concerns about the ongoing pressures on freshwater habitats in the region.

Local resident and long-time volunteer Ash Walsh, who has lived beside the creek for 26 years, expressed devastation over the loss. Walsh, who has been actively involved in the creek’s restoration, said the situation was disheartening given the progress made, and underscored the uncertainty about how to begin recovery efforts after such extensive damage.

The cause of the spill is under investigation, with calls from community members for increased vigilance and greater public awareness about the potential impacts of disposing chemicals into stormwater drainage systems. The incident has prompted renewed calls for stricter controls around construction and industrial sites to prevent similar environmental harm in the future.