British Mandate: A Survey of Palestine: Volume I - Page 399

CHAPTER X.

INVESTIGATIONS INTO UNDERGROUND WATER.

38. In the absence of legislation to compel well owners to furnish particulars about the draw-down of the Witter after pumping, the output and the chemical composition of the water in their wells, it is difficult to obtain all the information necessary for a study of the water table. Nevertheless the Water Commissioner's staff have been able to make some progress without the help of statutory powers.

39. A Government survey of some 2,550 wells and boreholes, chiefly on the coastal plains, was made in 1934 and 1935; water levels were recorded in order that any future change might be easily detected. Since that time water levels have been regularly taken at a number of typical test wells which are being used as permanent record stations and at present the Water Commissioner's staff observes 120 such wells regularly at monthly intervals. Regular information regarding some 165 other wells is also being ascertained from the Palestine Water _Company, the Water Research Bureau of the Jewish Agency and other private undertakings. By this means changes in water level are to some extent being kept under observation in the hope of detecting any overdrawing. Near Tel Aviv over-pumping has caused excessive suction which has resulted in the intrusion of salt water from the sea : in the Haifa sand dunes a similar disastrous phenomenon is threatened. Between Lydda and Rehovoth a fall of seven metres in the water table has been observed. A drop of this magnitude is a red light and counsels caution. With the exception of those three areas in which the lowering of the water table has given cause for concern, there is, generally speaking, room for a considerable increase in pumping from the underground reservoirs of the country, provided that Government has the necessary statutory powers to control the exploitation. Failure to acquire and exercise such power might bring a disaster.

EXPLORATORY DRILLING.

40. Shortly before the war a programme of exploratory drilling was begun; 48 trial boreholes had been made in various parts of the country but work was stopped by the disturbances. The war followed and further operations were suspended. Arrangements have been made for future investigations to cover more fully the Beersheba desert, the foothills between Gaza and Lydda, the Qaqun area, and the inland plains of Esdraelon, Araba and Battauf.

WATER DUTY.

41. The Water Commissioner's staff are carrying out a number of experiments with the object of ascertaining the optimum water

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