Wellington, New Zealand’s capital, is facing a major environmental and public health crisis after a catastrophic failure at the Moa Point wastewater treatment plant sent tens of millions of litres of untreated sewage into the sea, closing beaches along the city’s south coast and prompting warnings from authorities for residents to avoid coastal waters and shoreline areas.
The incident began in the early hours of Wednesday when heavy rainfall overwhelmed the infrastructure at the Moa Point facility, which normally processes the city’s wastewater and discharges treated effluent 1.8 kilometres offshore into Cook Strait. Flooding caused by the storm forced sewage and stormwater to back up inside the plant, submerging lower floors and crippling key equipment. With the main outfall incapacitated, overflowing wastewater began discharging directly into the sea through a much shorter, five-metre pipe closer to shore, releasing an estimated 70 million litres of untreated sewage into the coastal waters each day.
Officials from Wellington Water, which manages the plant, confirmed that damage to the facility is extensive and that full repairs could take months, even as engineers work to restore normal operation. In a late update, staff said they had partially reactivated the long outfall pipeline and corresponding screening systems designed to remove solids such as sanitary products before discharge. At present, the system is capable of pumping around 900 litres per second—enough to handle most typical flows—but during peak usage or heavy rain, discharges via the short pipe may continue.
In light of the spill, public health notices remain in place advising people to stay out of the water, avoid fishing or collecting seafood (known locally as kai moana), and keep pets away from contaminated areas. Water testing by Wellington Water found elevated levels of harmful bacteria such as enterococcus at several sampling sites along the coast, underscoring persistent health risks despite efforts to redirect outflows.
Wellington’s mayor, Andrew Little, denounced the failure as a “catastrophic” event and called for an independent inquiry into the causes of the breakdown, which comes amid mounting frustration over longstanding infrastructure issues. Local conservation authorities, including the Department of Conservation, have expressed deep concern about the potential ecological harm to marine ecosystems, warning that species such as mussels, kina (sea urchins), pāua (abalone), sponges, fish, and even penguins could be threatened if contamination persists.
The spill has also dealt a significant blow to businesses that depend on the coastal environment. Dive operators and snorkelling tours based near the Taputeranga Marine Reserve have reported cancellations and financial hardship as restrictions keep visitors away. A rāhui—an indigenous Māori temporary ban—has been placed from Ōwhiro Bay to Breaker Bay to reinforce the closure and respect cultural protections for the coastline.
As Wellington grapples with the fallout, residents have voiced anger and disappointment over the scale of the failure, which has not only marred beloved beaches but also highlighted vulnerabilities in the city’s ageing wastewater infrastructure. With repairs expected to be prolonged and the full ecological toll still unknown, authorities are under pressure to both contain the current crisis and prevent similar episodes in the future.
