Vízügyi Közlemények, 1998 (80. évfolyam)

3. füzet - Rövidebb tanulmányok, közlemények, beszámolók

Vízrendezési problémák Izraelben 535 A munkálatok lassan befejeződnek, a termelés beindult, most lép előtérbe egy újabb fázis: a monitoring rendszer kiépítése, a terület folyamatos figyelése. IRODALOM Bazelet M.: Israel's Agriculture. Tel-Aviv, 1996. Gophen M.-Levanon, D

.: The Hula Project: Enviromental perspectivies. Preservation of our World in the Wake of Change ISEEQS Pub., Vol VI A/B, Jerusalem. 1996. * * * Water management problems in Israel by Péter ROSZA C.E. Israel (Figure 1.) is located, along with other countries of the Near-East, in a very arid climate zone, thus facing several problems of water management. The largest water management problem of the area is associated with the very low precipitation and its uneven distribution both in time and space (Figure 2.). Higher summer water demands can be satisfied with the help of storage only. Reservoirs of larger size, however, can be constructed in the northern region only, where the larger rivers are found. The only fresh water lake of the area, the Galilean Sea or Lake Kineret also known from the Bible, is also located in this region, providing the water resource for 50% of drinking water supply. 170 reservoirs have been built in the country, most of which serve for drinking water supply purposes. There are however, recreational lakes, fish ponds, irrigation and multi purpose reservoirs as well. One of the major tasks of water management is to convey water to the southern region from the reservoirs. The Canal National Water Carrier (NWC) of more than 200. km length serves also for this purpose (Figure 3.). It forks off from the Lake Kineret with several side branches connecting to smaller reservoirs, pumping stations and water treatment plants. Another water distribution facility is the open surface concrete canal of 22 km length, called the Saline Carrier, which collects saline waters thus protecting Lake Kineret from the water of saline springs found below its surface and from the also saline inflowing streams arriving mostly from the west. River Jordan flows through the Lake Kineret (Figure 1.). In the outflow section a river dam and outlet gate was constructed, which allow the operation of the lake as a reservoir. River Jordan has much varying hydrological regime in this section, with 5 m

3 s~' summer mean flow and 50-500 m

3 winter flows. Flows exceeding 1,000 m

3 s1 have also been observed upon extreme rainstorms. Valley Hula (Figure I.) is located north of Lake Kineret below the Golan plains. In the middle of this valley the Lake Old Hula was found in earlier times, through which the River Jordan was flowing, similarly to the case of Lake Kineret. Lake Old Hula was an ageing eutrophic lake surrounded by wetlands. River Jordan collected much debris of high nutrient content from this lake transporting it to Lake Kineret. The Lake Old Hula and its surrounding marshlands were drained and dried in the 1950-ies. Water of the River Jordan has been diverted via two canals (the western and the eastern canals) and the land was given to the farmers. This action was made in the hope that substantial areas can be brought under agricultural cultivation, with the simultaneous reduction of nutrient loads to Lake Kineret. This was the first stage of the water management action plan of the Hula valley, completed in the early 1960-ies. In spite of all these efforts the River Jordan has continued to transport substantial nutrient loads into Lake Kineret. More than 50% of the nitrogen, phosphorus and sulphate loads of Lake Kineret originated from this area, endangering the stability of the quality of water of the lake. New programme has been launched in 1990, called the "Hula-Plan",