New sinkholes threaten roads around the Dead Sea
Haaretz
June 5, 2007
By Zafrir Rinat
A disaster not covered by any law or security framework and unrecognized by everyone - that is how a recent government policy paper described sinkholes in the Dead Sea basin. And according to a recently released report by the Geophysical Institute of Israel, the problem is only getting worse.
The report found that there are already more than 1,700 sinkholes - depressions in the earth's surface that can cause serious damage to infrastructure, tourism and agriculture - on the Dead Sea shore. Some of these sinkholes are located less than 100 meters from Route 90, the sole road that passes near the sea. The Megillot Regional Council warned last year that the depressions could endanger traffic in the area.
In their study of the area, institute researchers found that while new sinkholes have been developing at a slightly slower pace, there are still an average of 200 new sinkholes every year. The sinkholes vary in size, but some reach a diameter of over 12 meters and some a depth of five.
In the Dead Sea basin, such depressions are caused by dissolution of the underlying salt. The sinkholes have their roots in the ongoing reduction in the water level - by about one meter per year - that is occurring because water that was supposed to flow into the Dead Sea from the Jordan River and elsewhere has been diverted for drinking and irrigation purposes in Israel, Jordan and Syria. The water level reduction means that there is less salty groundwater and more sweet groundwater, which dissolves the underground salt bed and causes underground depressions. As the salt dissolves, spaces develop underground and the ground surface can collapse, sometimes taking with it a house or roadway.
The Jordanian side of the Dead Sea also has some sinkholes, but far fewer than the Israeli side, due to the steeper structure of the Jordanian shore.
The researchers who compiled the Geophysical Institute report also demonstrated that experts today can predict which areas will develop sinkholes, on the basis of a geological analysis of field conditions. Three years ago, institute researchers mapped out areas that they thought were likely to develop sinkholes, and the report shows that all the new sinkholes found since then did indeed develop in those high-risk areas.
In the Ein Gedi region, which sees heavy local and international tourism, the sinkholes have already led to the closure of a parking lot and a ban on entering some of Kibbutz Ein Gedi's date orchards. Several sections of roadway have also been damaged.
"The sinkholes are forcing us to abandon areas designated for the development of tourism and agriculture," said Dov Litvinoff, head of the Tamar Regional Council, which includes part of the Dead Sea coast. He urged environmental groups to allow tourism and/or agriculture in nature reserves in the area.
"At present, we can't develop east of Route 90 because there are sinkholes there, and we can't develop west of the road because there are nature reserves there," said Litvinoff. "The environmentalists have to compromise and allow the development of tourism or agriculture in nature reserves as well. Otherwise, we won't be able to survive here."
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