GUJARAT, INDIA (Reuters) - For millions of people across western India, water is in short supply.

Villagers throughout the region now rely on water delivered by train.

But residents say the aid convoys are too few for the many who need the water.

"They say water has been brought by railway wagons and dispatched through tankers. All this they say to the media, but in this part of the city, one water tanker makes a trip only after eight days," said resident Haribhau Kamble.

And there's no end in sight.

Fuelled by scorching temperatures, the worst drought in four decades has emptied reservoirs, killed livestock, destroyed crops and left much of the population desperate for water.

And amid this latest heat wave, even the animals at the zoo in the western city of Surat are struggling to stay cool.

Temperatures are already more than four deg higher than this time last year, and the hottest months of the year are yet to come.

During May and June the heat peaks, often claiming numerous lives, leaving many to fear that even worse days lie ahead.