Arabs may drink melted snow

Press, 30 April 1982, Page 14

Arabs may drink melted snow

From

FABIAN ACKER

in Marseilles

Arabs may soon be drinking melted snow from the French Basses Alpes, thanks to the remarkable ability of an enterprise originally created to supply water to the parched towns and fields of Provence. The Canal de Provence company has met its obligations so effectively that it now has water to spare. It has equipped the Mediterranean port of Lavera to load ocean-going tankers, and believes it will be able to ship water to arid countries such as Saudi Arabia, Kuwait, and Malta at least as cheaply as it can be desalinated locally.

The rewards of good husbandry and careful planning become more evident in Provence every year. Last summer, a drought affected all the Mediterranean countries, bringing a sharp fall in agricultural output, but not in Provence, where the fields and cities, such as Toulon and Marseille, were supplied with as much water as they could use.

Provence, stretching from the Durance River to the Mediterranean, is semi-arid, yet its crops help to keep France a world leader in the export of agricultural produce — once called “our green petrol” by former President Giscard d’Estaing. The key to the success of

agriculture in Provence lies 'in an irrigation system comprising miles of canals and tunnels, pumping stations, and reservoirs. What the Romans did with aqueducts, the French now do with computers and pumps. Appropriately, it is in the shadow of a broken aqueduct that the Canal de Provence company houses its two P.D.P computers and

control centre for the whole network. Here, on the second floor of a graceful eighteenth century building, the progress of each cubic metre of water is monitored and controlled automatically from the point when it enters the system, perhaps in the Basses Alpes region, until the moment it is shot out of a sprinkler in the field, or comes out of a tap in a Marseille tenement.

Three elements are at the heart of the scheme. They are the 58 gates and 18 pumps which control the flow of water, the 200 sensors which indicate the flow rate, water level, and gate • position, and the computer programme which can integrate these components

and at the same time provide more than 1000 signals of the system’s condition. A large wall display indicates the physical arrangements of the . system, and shows the positions of the main components. At the control desk, the operator keys in instructions and the screen then indicates, for instance, the degree of closure of any selected gate or valve. The operator is also informed of the level of the water at the selected spot, and its rate of flow. He can reduce or increase the flow if necessary, although the computer is programmed to do all this automatically. The ability of the operator to take over is, however, an important back-up, although with three independent power supplies and two computers, the risk of breakdown at the centre is very small. If the company succeeds in

its plans to export surplus water, the phrase “green petrol” might take on a deeper meaning. “After all,” says a company engineer, referring to Saudi Arabia, “even if you’ve got millions of barrels of oil underneath you, it won’t quench anybody’s thirst.” Copyright — London Observer Service.