The booming desert emirate of Dubai has begun building three giant reservoirs to meet fast growing demand for water, the official WAM news agency reported.

"With rapid population growth and economic development driving an exponential increase in demand for water, governments throughout the region are continuously boosting supply to keep pace," Behzad Ferdows, of the Mammut Group building the reservoirs, told WAM.

The reservoirs will hold a combined total of 180 million gallons (almost 820 million litres) of drinking water once construction is completed in 15 months, WAM said.

Dubai's population of 1.3 million is growing at a rapid rate as the wealthy city-state continues to transform itself into a global finance and travel hub.