ISLAMABAD - Authorities in flood-hit Pakistan have breached the country’s largest freshwater lake, displacing around 100,000 people from their homes but saving more densely populated areas from flood water.

Engineers cut into an embankment of Lake Manchar to release rising waters in the hopes of protecting about half a million people who live in the city of Sehwan and the town of Bhan Saeedabad.

Although it aims to save more heavily populated areas, villages that are home to 100,000 people are in the path of diverted waters.

Manchar Lake, which is used for water storage, had already reached dangerous levels and the increased pressure posed a threat to surrounding areas in southern Sindh province, Sindh irrigation minister Jam Khan Shoro said.

It comes as officials predicted more monsoon rain was on the way for the country’s already devastated south.

“By inflicting the breach we have tried to save Sehwan town. Water levels on Johi and Mehar towns in Dadu district would be reduced by this breach in the lake,” Mr Shoro said.

The hometown of Sindh province’s chief minister was among the affected villages, the residents of which were warned to evacuate ahead of time, the government said.

More than 1,300 people have died and millions have lost their homes in the flooding caused by unusually heavy monsoon rains in Pakistan this year that many experts have blamed on climate change.

In response to the unfolding disaster, UN secretary general Antonio Guterres last week called on the world to stop “sleepwalking” through the crisis. He plans to visit flood-hit areas on 9 September.

Several countries have flown in supplies, but the Pakistani government has pleaded for even more help, faced with the enormous task of feeding and housing those affected, as well as protecting them from waterborne diseases.

While floods have touched much of the country, the Sindh province has been the most affected.

With meteorologists predicting more rain in the coming days, including around Sindh’s Lake Manchar, and its level already rising, authorities ordered that water be released from it.

In its latest report, Pakistan’s National Disaster Management Authority put the death toll since mid-June – when monsoon rains started weeks earlier than usual – at 1,314, as more fatalities were reported from flood-affected areas of Sindh, Khyber Pakhtunkhwa and Baluchistan provinces. The report said 458 children were among the dead.