The four children died in the Klipfontein informal settlement, local news reported, citing Cape Town’s Disaster Risk Management Center. The other four deaths occurred in a settlement in Driftsands, a nature reserve where thousands have sought shelter since 2020.

Overwhelmed by rapid population growth and urban expansion, South Africa has around 11 percent of its population living in informal dwellings, according to a 2021 Statistics South Africa survey. The percentage is higher in cities including Johannesburg (17.3 percent) and Cape Town (16.6 percent) — and has surged further since the country’s strict pandemic lockdown in 2020.

Informal settlements largely lack regular sanitation services, electricity and running water — further increasing the vulnerability of residents. During heavy rains, the informal settlement in Driftsands, near a major dam, becomes inundated in knee- and chest-deep water that can persist for weeks. The thousands of shacks built on the Klipfontein settlement are often waterlogged. They rely on illegal and informal electricity and water connections, as well as city-provided portable toilets, according to South African public interest news organization GroundUp.

“We’ve seen the impact of the flooding and the heavy rains causing disaster within our communities,” Cape Town’s Mayoral Committee Member for Human Settlements Carl Pophaim said in a statement Tuesday. He said that during the covid-19 pandemic and related lockdowns, 186 new informal settlements were created — around 60 percent of which are “high risk” due to their location under power lines or in wetlands.

Pophaim said that the city observed “a worrying trend” of growing informal settlements — even as the funds allocated to the problem dwindled. He said the government aimed to address informality “within limited resources and land,” including by working to upgrade sites of newly established settlements.

With the skies clearing, the Cape Town government said Tuesday that it has moved on to “mopping up operations” across the city, specifically in informal settlements. Around 12,000 people have been affected by the storm, it said.

The heavy rainfall this week — which prompted a high ‘Orange Level 9’ warning by the South African Weather Service — is another sign of climate change intensifying extreme weather events, local officials said. More than 400 people died in severe flooding in South Africa in April last year.

“The heavy rains are an indication of climate change, and while our early warning and mitigations systems did work, we have to keep investing,” Anton Bredell, Western Cape’s provincial minister of local government and development planning, said this week, according to Bloomberg.