South African cities that are home to almost 30% of the country’s population face water outages as the nation’s biggest water distributor struggles to stabilize reservoirs levels.

Rand Water will take over full control of water supply in an area that includes the capital, Pretoria, Johannesburg and the adjacent industrial hub of Ekurhuleni that’s home to the country’s biggest airport, the utility said in an emailed statement on Friday. That means it will no longer rely on customers to reduce consumption and can cut the supply if needed to avoid the emptying of reservoirs and avert a complete system crash, it said.