Highway currently runs through one of the most active sinkhole areas. Environmentalists: New route will harm animals, nature.
By Nir Hasson | Apr. 17, 2015

The Geological Survey of Israel, as well as most senior Israeli geologists, say the best solution for Road 90 along the coast of the Dead Sea in the Ein Gedi area is to move it farther to the west, near the Ein Gedi Nature Preserve – despite fierce opposition by environmentalists. The road was closed in February after more sinkholes opened up nearby, and a detour was built that takes traffic past the entrance to the nature preserve.

The Israel Roads Company also prefers building a new route to the west, say geologists involved in the matter, but it will be months before a final decision is made.

The change in the route would move the main road close to Kibbutz Ein Gedi and the boundaries of the nature reserve in the David and Arugot streams, and be built on agricultural land used by the kibbutz, and also by wild animals.

The far-reaching decision would have major effects on the landscape and wildlife in the region. The Israel Nature and Parks Authority is demanding that if the road is paved near the reserve, it be built either on a bridge or inside a tunnel, so as not to destroy the continuity of the animals’ ecological living space.

The problems all stem from the drying up of the Dead Sea. The sea receives much less fresh water than it did only a few decades ago, because the water that used to reach it is now being used for agriculture and other uses by Israel, the Palestinians and Jordan. In addition, both the Jordanian and Israel Chemicals potash plants draw large amounts of water from the Dead Sea. Then there are the effects of climate change and warming.

The drying of the sea has caused the water line to recede, flash floods have become stronger – and have also washed out the highway – but the biggest problem is the sinkholes. These are formed because the level of the Dead Sea, the saltiest body of water in the world, has fallen by about 40 meters over the past 50 years. As a result, the salty groundwater under the land along the sea’s edge has receded and lowered, and instead this area has been filled with fresh water, which eats away at the underground salt deposits, which at some point, in turn, become eroded enough to cause the surface overhead to collapse from the weight and form sinkholes.

Short and long term solutions

For the past two decades the government has tried to find ways to deal with the increasing number of sinkholes in the region. The situation has gotten much worse lately and the large Dead Sea beaches in the area have been closed – along with the main road, with the most problematic area for road maintenance being the 1.5-kilometer stretch around Ein Gedi, where sinkhole activity is greatest.

The bypass that was opened two months ago is narrow and can only handle traffic in one direction at a time, which requires traffic in the other direction to be stopped for 10 to 15 minutes at a time, though traffic jams can increase this wait to over an hour. Trucks are not allowed on the bypass, and often must make a huge detour to the south end of the Dead Sea and travel via Arad.

Over the past three years, the Roads Company, Ministry of Transportation and Tamar Regional Council, where Ein Gedi is located, have been trying to come up with a long-term solution. There are two main alternatives on the table: The first is to stay with the present route of the road and use complex, very expensive engineering methods to protect the road from the sinkholes.

The second possibility is to move the road to the west and construct it on top of ground that does not have salt layers underneath, which are the source of the sinkhole danger. The problem is that the new route will come at the expense of the very small amounts of agricultural land in the area. It would also be very near the nature reserve and the animals’ natural habitats, which could endanger them.

“The ibexes don’t know where the boundary of the reserve is,” noted the reserve’s director.

Before making a final decision on a route, it will be necessary to drill a number of test boreholes to precisely map out the extent of the underground salt layers in the area.

The Roads Company recently received an engineering report evaluating the various alternatives. Rebuilding the existing road would require not only a 100 million shekel ($25 million) new bridge over the Arugot Stream, but also require costly, continuous maintenance. Another proposed solution is building a kilometer-long bridge over the present route of the road, at a cost of 330 million shekels. The way to prevent disaster this time would be to sink very deep foundations for the bridge, below the salt layers.

Another solution would be to build a huge ditch, 80 meters deep, to remove the entire salt layers, and then to rebuild a berm on top where the new road would run. The estimated cost of this solution is 635 million shekels.

The engineers recommended fixing the existing road, but there is fierce opposition to this solution too. Local geologists and activists say any solution leaving the road where it is will not last in the long term, and may increase the sinkhole effect over time.

The Israel Roads Company said it is “holding consultations with experts in geology, engineering and the environment to find a practical and optimal solution, both for drivers and to protect the environment. But the conditions in the region are complex, to say the least, and there are changes going on underground that are impossible to predict.”

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