Update for 11.3.2012
The elevation of the Sea of Galilee today is 211.96 meters below sea level
Top line-The maximal elevation for the Sea of Galilee is -208.80 meters.
The Red Line-The higher danger line is -213.00 meters.
The black line-The lower danger line is -214.87 meters.
The Sea of Galilee or Lake Kinneret
The Sea of Galilee (or Lake Kinneret) is the largest fresh-water lake in Israel. Water is pumped from Lake Kinneret and transported via the Israel Water Channel to supply 25% of all the water used in Israel. Lake Kinneret is located in the north of Israel in the Great Rift Valley. The high-water mark for Lake Kinneret is -208.80 meters. Above this level the Lake would overflow its banks and flood the city of Tiberias. The lowest water level ever recorded was on November 29, 2001 at -214.87 meters. This was 6.07 meters below the maximal elevation and has since been known as the "black level".
The higher danger level is -213.00 meters. There are salt-water streams under the Kinneret which do not flow up into the fresh water of the Kinneret because of the pressure of the water. It is feared that were the water of the Kinneret to drop precipitously the pressure exerted on these streams would weaken sufficiently and let the salt water mix with the fresh water of the Kinneret compromising it for general use.
In recent years a worrisome drop in the number of fish in the Kinneret has occurred because of the drop in the water level and uncontrolled over-fishing. A ban on fishing in the Kinneret was imposed in January, 2011. The hope is to replenish the dangerously low fish supply.
The area of the Kinneret, when it is full, is 169 sq. km. and its greatest depth is 47 meters. The lake bed is 256 meters below sea level. Lake Kinneret is filled by precipitation that falls in the Galilee, the Golan Heights and Mount Hermon in the river beds or wadis. The wadis are dry or nearly dry in the summer but flow strongly after heavy winter rains. Some promimnent wadis are Meshushim, Amud, El Al, and Yehudia. Another major source is rain that falls onto the lake itself. Average rainfall over the Kinneret is about 400 mm per year.
Daytime air-temperature highs are 17-18° Celsius in the winter and 38° Celsius in the summer. Water temperatures range between 15-17° in the winter and reach 28° in the summer.
The Degania Dam divides the Kinneret from the southern Jordan River. Because of the low precipitation levels and the low level of the Kinneret, the Degania Dam has mostly been closed in recent years. Only the smaller section of the dam has been open to allow some flow of water into the southern portion of the Jordan River primarily in order to maintain the local ecology.
The Dead Sea
The Dead Sea is the saltiest body of water in the world. Salinity in the Dead Sea is 34% whereas the Mediterranean Sea is only 3.5-4% salt. The Dead Sea loses one meter each year in depth. In January, 2011, the elevation of the Dead Sea was 424.30 meters below sea level (-424.30 meters). The dramatic decrease in depth of the Dead Sea has also shrunk its size. At the end of the 20th century the Dead Sea covered 930 sq. km. Today, in 2011, it covers only 620 sq. km. In the past thirty years the level of the sea has decreased 26 meters. The rapid shrinking of the Dead Sea is causing the sudden appearance of sinkholes, posing a serious danger to bathers and travelers.
The Dead Sea is located in the Great Rift Valley at the lowest point on Earth. It is one of the natural wonders of the world. There are several sources of water for the Dead Sea. The primary source is the Jordan River. This source has provided less water in the past for two reasons. One, the water crisis in Israel has led authorities to allow less water to flow out of the Sea of Galilee into the Jordan River. The second is the terms of the peace accord of 1993 between Israel and Jordan under which Jordan may divert water from the Jordan River.
A second major source of water for the Dead Sea is flash floods in the Judean Mountains, the Hebron Mountains, and the Edom Mountains of Jordan. Precipitation around the Dead Sea ranges from 80mm to 120mm annually.
Air temperature in the winter is in the 18-20° Celsius range but in the summer temperatures regularly reach 40° Celsius. Because of the cold nights, winter water temperature is 15-16° Celsius. Summer water temperature reaches 36°. Even in the summer the water loses heat quickly. At a depth of only two meters the water temperature in the summer will be 4-6° Celsius lower than at the surface.
The Dead Sea is actually two bodies of water connected by a channel. The channel brings water from the northern part to the southern part. Otherwise, the southern part would be completely dry. Dead Sea industries and many hotels are located on the shores of the southern section. An ironic problem that has appeared recently is the sinking of salt in the southern part which is causing the level of the water to rise. There is the fear that the hotels along the stores will be flooded. Two possible solutions have been offered to deal with this problem: intensive mining of the salt or relocation of the hotels a safe distance from the shore.