The Sea of Galilee, known also as Lake Kinneret and Lake Tiberias, is a body of water steeped in religious and historical tradition. This lake, situated deep within the Jordan Rift Valley, is definitively classified as freshwater. It holds the distinction of being the lowest freshwater lake on Earth, with its surface lying approximately 209 to 215 meters below sea level, depending on water levels.
Defining the Freshwater Status
The Sea of Galilee maintains its freshwater status primarily due to its active flow-through system, which acts as a natural flushing mechanism. The main source of water is the Upper Jordan River, which flows into the lake from the north, delivering a massive volume of low-salinity water.
The lake also has a primary outflow where the Lower Jordan River exits from the southern end, preventing the continuous accumulation of dissolved salts and minerals. Because of this hydrological balance, the water’s chloride concentration remains low, typically fluctuating in the range of 190 to 280 milligrams per liter (mg/L). This low concentration places the Sea of Galilee in the oligohaline category, far from the 35,000 mg/L average of the world’s oceans.
Geological Factors Influencing Water Composition
The occasional confusion about the lake’s classification is due to its unique geological setting, which introduces localized sources of salinity. The Sea of Galilee is positioned in a pull-apart basin along the northern section of the Great Rift Valley, a major tectonic boundary. This geological activity results in the presence of subterranean thermal and saline springs that feed directly into the lake.
These deep-seated springs introduce mineral-rich groundwater, with some sources containing chloride concentrations as high as 18,000 mg/L, significantly saltier than the lake’s average. Specific saline spring areas contribute this brackish water, such as those near Tiberias, Fuliya, and offshore sites like Barbutim and Maagan. The freshwater inflow from the Jordan River, however, is generally sufficient to dilute these concentrated saline contributions, preventing a permanent increase in the overall salinity.
To protect the lake’s water quality for human use, a system called the Salty Carrier was historically constructed to divert the most concentrated saline spring flows away from the lake. This engineering effort maintains the delicate balance.
Critical Importance of the Water Source
The lake’s freshwater classification is important to the surrounding region. It serves as Israel’s largest natural freshwater reservoir and is a critical component of the National Water Carrier system. This national network of pipes, canals, and pumping stations historically transported water from the north to the arid central and southern parts of the country for agricultural and domestic use.
Although large-scale desalination projects have reduced the nation’s daily reliance on the lake, the Sea of Galilee remains a national emergency water reserve. It provides a secure backup source for drinking and irrigation in the event of infrastructure failures or prolonged drought. The water is also important for regional stability, as Israel supplies water from the lake to the neighboring country of Jordan under the terms of a peace treaty.