New Zealand’s capital of Wellington was flooded with raw sewage and sanitary products after an overnight storm overwhelmed its already crippled wastewater system.

The storm sent untreated waste into homes and back into the sea in a city that has been battling a sewage crisis for four months.

Wellington Water said five properties in the suburb of Island Bay were affected after a blocked main caused a wastewater overflow on Friday morning. Its crews were on site with a suction truck to remove the waste and disinfect the affected homes.

“We are working with property owners to assist with cleaning and disinfecting,” it said in a statement.

Island Bay resident Richard Peters told national broadcaster RNZ the situation worsened as the floodwater receded.

“It was literally pieces of poo on the ground, tampons and brown water,” he said. “Feral and disgusting.”

Footage showed tampons, toilet paper, and sewage washing down Island Bay’s main thoroughfare during the night as water backed up through drains. A local daycare had to be closed after being flooded by sewage, media reported. Manhole covers were blown off by the pressure surging through the pipes.

New Zealand’s MetService recorded more than 5,000 lightning strikes overnight in Wellington as a thunderstorm dropped 25.7mm of rain on the city in two hours.

Wellington mayor Andrew Little visited the scene, speaking with affected residents and staff.

The storm compounded an existing crisis at the Moa Point wastewater treatment plant, which processes sewage for approximately 180,000 people and handles around 90 per cent of the city’s wastewater.

The plant suffered a catastrophic breakdown on 4 February when heavy rain surged through its systems, flooding facilities with untreated waste and forcing an emergency shutdown.

The long outfall pipe into Cook Strait became blocked, causing sewage to back up into the facility and inundating control rooms, electrical equipment and treatment tanks.

Around 70 million litres of untreated wastewater per day were discharged through a short five-metre emergency outfall pipe near Tarakena Bay, spewing directly onto the shore.

Wellington Water said Friday’s thunderstorm had led to more untreated wastewater being pumped into the sea overnight and advised residents to stay away from Tarakena Bay and avoid swimming, surfing or kayaking along Wellington’s south coast until further notice. The plant will not be fully operational until November.

A 2020 mayoral taskforce found 30 per cent of Wellington’s drinking water assets and 20 per cent of its wastewater networks had exceeded their useful life, concluding that the current approach was failing and that decades of neglect had created an escalating crisis.

Island Bay business owner Fran De Gregorio said she had zero faith in the system.

“All you’ve done is put this beautiful stuff on top of s*** — and now we’re actually getting the s*** literally,” she told 1News.

“Why do we pay rates? This is basic infrastructure. This is just a basic need.”

She said she had been bounced between Wellington City Council, Wellington Water and roading contractor Higgins trying to get longstanding leaks fixed. “I’m sick of being fobbed off from entity to entity. I just want it fixed.”

Emerson Nikora, a resident who was displaced from his Island Bay home in April’s floods, said the community was heading into winter with no confidence the system could handle heavy rain.

“Enough is enough. Every time a bit more rain turns up, we’re all feeling very anxious and frightened,” he told 1News. A community meeting on flooding had been scheduled for Saturday, which he expected the overnight incident to dominate.