Pakistan's Manchar Lake breached to drain water threatening nearby towns

Engineers have breached Pakistan's biggest freshwater lake to drain water threatening nearby towns as heavy rain poured misery on millions affected by the country's worst floods in history.

Nearly a third of Pakistan is under water –– an area the size of the United Kingdom –– following months of record monsoon rains that have killed 1,300 people and washed away homes, businesses, roads and bridges.

Officials on Monday said the repair bill will top $10 billion for a country already in the grip of economic crisis, with hundreds of thousands homeless as the monsoon draws to an end and winter approaches.

"There is nowhere to shower or go to the bathroom," said Zebunnisa Bibi, sheltering near Fazilpur, in Punjab province, where 65 tents are now home to more than 500 people who fled their inundated villages for higher land.

Similar tent camps have mushroomed across much of the south and west of Pakistan, where rain has nowhere to drain because rivers are already in full flow as a result of torrential downpours in the north.

Sindh province Information minister Sharjeel Inam Memon said that engineers had to cut a channel into Manchar Lake to drain water that was threatening the towns of Sehwan and Bhan Saeedabad, with a combined population of nearly half a million.

READ MORE: Death toll from Pakistan floods tops 1,300 as international aid pours in

Manchar Lake bigger than ever 

Still, thousands had to be evacuated from smaller settlements submerged by the newly directed channel.

"The flood water was diverted but the threat is still far from over," Memon said.

"We are trying our best to stop the inundation of more villages."

Manchar Lake, which lies west of the Indus River and south of Dadu, varies in size according to the season and rainfall but is currently spread over as wide an area as anyone can recall.

Much of Sindh and parts of Balochistan have become a vast landscape of water, with displaced locals huddled miserably on elevated roads, rail tracks and other high ground.

Human and animal waste in the fetid water attracts swarms of flies, while outbreaks of dengue are being reported from mosquitos breeding in the swamplands.

READ MORE: Food crisis looms as vegetable prices spike in flood-hit Pakistan

Pregnant women caught in floods

One pregnant woman at a camp in Punjab said she was desperate for medical attention for a baby due any day now.

The mother-of-five knows it could be a difficult birth, as the baby has not shifted from the breech position.

"I need a doctor or a midwife. What if something happens to my child?" said Fahmidah Bibi.

The United Nations Population Fund said at the weekend there were at least 128,000 pregnant women in flood-hit areas who urgently need care – with 42,000 expected to give birth in the next three months.

Pakistan receives heavy –– often destructive –– rains during its annual monsoon season, which are crucial for agriculture and water supplies.

But such intense downpours have not been seen for decades. The last such deadly floodings hit Pakistan in 2010. 

Pakistani officials blame climate change, which is increasing the frequency and intensity of extreme weather around the world.

Pakistan is responsible for less than one percent of global greenhouse gas emissions but is eighth on a list compiled by the NGO Germanwatch of countries deemed most vulnerable to extreme weather caused by climate change.