The Sea of Galilee, also known as Lake Kinneret or Lake Tiberias, is the lowest freshwater lake on Earth. It is a large lake, not a sea, whose surface sits significantly below the global zero-point of elevation. The average surface level fluctuates between approximately 209 and 215 meters below mean sea level, depending on annual rainfall and water management practices.
Defining the Exact Elevation
The precise measurement of the Sea of Galilee’s surface is consistently recorded as a negative elevation relative to Mean Sea Level (MSL). MSL is the standardized reference point, or zero datum, for all elevation measurements worldwide. Since the lake’s surface sits far below this global average, its elevation is typically cited as a range, such as -209 meters to -215 meters.
This variable range reflects the hydrological cycle and human intervention. The lower figure indicates a full lake, while the higher (more negative) figure represents a dry period. This elevation makes the Sea of Galilee the lowest freshwater lake globally, surpassed only by the hypersaline Dead Sea to the south. Water authorities critically monitor this level, as the lake serves as Israel’s largest natural reservoir of potable water.
Geological Setting: The Rift Valley Connection
The profound depression that hosts the Sea of Galilee resulted from massive tectonic forces over millions of years. The lake is situated within the Jordan Rift Valley, a northern segment of the larger Great Rift Valley system extending from Turkey to East Africa. This valley is a geological feature known as a transform fault boundary, marking the seam where the African and Arabian tectonic plates meet.
The two plates move slowly past each other in a horizontal, or strike-slip, motion, causing the land between them to stretch and subside. This process created a deep geological trough known as a graben—a sunken block of the Earth’s crust bounded by parallel faults. The Sea of Galilee occupies a pull-apart basin formed along this fault line, creating a deep basin far below the surrounding landscape.
The lake’s low elevation is a permanent feature of the Earth’s crust in this area. The surrounding landscape rises sharply, with the hills of Galilee and the Golan Heights towering over the water. This dramatic topography emphasizes the lake’s deeply sunken position and also contributes to localized wind patterns and storms.
Surface Elevation Versus Maximum Depth
It is important to distinguish the lake’s surface elevation from its maximum depth, as they describe different aspects of the water body. Surface elevation, given as a negative number like -212 meters, refers to the height of the water’s surface relative to the average ocean level. This figure indicates the vertical distance one must descend from mean sea level to reach the lake’s surface.
Maximum depth, in contrast, is a positive measurement describing how deep the water is from the surface down to the lakebed. The Sea of Galilee is relatively shallow, with an average depth of about 25.6 meters and a maximum depth reaching 43 to 48 meters, primarily in the northeast. If the surface were at -212 meters, the deepest point of the lakebed would be around -255 meters below sea level.
Water Level Management and Fluctuations
The Sea of Galilee’s elevation fluctuates significantly due to natural cycles and intensive human management. Annual rainfall, particularly during the winter months, is the primary natural factor influencing the water level. Droughts can cause the surface to drop dangerously low, while heavy rains can bring it close to maximum capacity. Israeli water authorities manage these fluctuations using defined “red lines” to protect the lake’s ecological health and prevent flooding.
Upper Red Line
The “upper red line,” set near -208.9 meters, indicates the level at which the Degania Dam must be opened to release water into the Jordan River and prevent flooding.
Lower Red Line
The “lower red line” is a variable administrative threshold, often around -213 meters. Below this level, water extraction is severely restricted to prevent ecological damage, such as increased salinity from underlying subterranean salt springs.
To combat drought and over-extraction, a project now pumps desalinated seawater uphill from the Mediterranean coast into the lake. This actively stabilizes its level and secures the nation’s freshwater supply.