The Kenyan government and UNESCO on Wednesday announced the discovery of a huge supply of underground water in the impoverished, drought-stricken extreme north of the country.

The find, made using advanced satellite exploration technology and backed up by UNESCO drilling, was hailed as a scientific breakthrough that could radically change the lives of the half-million people living in one of the world's most arid regions.

Two aquifers -- underground layers of permeable rock or silt soaked in water -- were found in the Turkana region, the scene of a devastating drought two years ago that aid workers said pushed malnutrition rates up to 37 percent.

"The news about these water reserves comes at a time when reliable water supplies are highly needed," said Judi Wakhungu, cabinet secretary in the Kenyan ministry of environment, water and natural resources.

"This newly found wealth of water opens a door to a more prosperous future for the people of Turkana and the nation as a whole. We must now work to further explore these resources responsibly and safeguard them for future generations," Wakhungu said at the start of a water security conference in Nairobi.

The firm which carried out the survey, Radar Technologies International (RTI), said the area hosts a minimum reserve of 250 billion cubic meters of water, which is recharged at a rate of 3.4 billion cubic meters per year -- almost equivalent to annual water consumption in Austria.

"Hundreds of thousands of livestock die because of recurring droughts. This won't happen anymore," RTI president Alain Gachet told AFP.

"We've just doubled the country's drinking water reserves. The needs are huge, as women often have to walk 10 to 20 kilometres to get water."

RTI said the largest find -- the Lotikipi Basin Aquifer, located west of Lake Turkana -- was roughly the size of the US state of Rhode Island.

The smaller Lodwar Basin Aquifer, meanwhile, could feed the parched regional capital of Lodwar -- although UNESCO cautioned that water quality still needed to be assessed.

The hostile and desert-like Turkana region, near the northern border with Uganda, South Sudan and Ethiopia, is the poorest in the country, and its mostly-nomadic people are among the most vulnerable in Africa.

Fighting between rival groups -- often armed with guns -- over grazing land for their livestock is common in the region.

Of Kenya's 41 million strong population, 17 million lack access to safe water, and 28 million do not have adequate sanitation.

Kenya's northern region already hosts Lake Turkana -- the world's biggest desert lake stretching 250 kilometres (150 miles) long by 60 kilometres wide at its largest point -- but the famous jade-coloured waters are threatened by hydroelectric dams cutting off feeder streams in neighbouring Ethiopia.

But water is not the only resource under the ground, with exploratory oil drilling ongoing.