The Galas aqueduct bridge in the Vaucluse department allows the 42.8 miles (69 km) long Carpentras canal to cross the Sorgue river. Exclusively intended for watering, the Carpentras canal was built from 1853 by the association of sprinklers on plans by the Ponts et Chaussées engineers Conte and Perrier. This work, essential for surface flow irrigation - also known as gravity irrigation that consists of distributing water through open canals and ditches under the effect of gravity - has enabled a transformation of the rural economy of the region.