Ramsar Sites of Turkey - Ramsar Convention on Wetlands

HYDROLOGICAL ASPECTS
Ceyhan River is significant in the formation <strong>of</strong> the delta. Ceyhan is among the significant
streams <strong>of</strong> <strong>Turkey</strong> in terms <strong>of</strong> its high volume <strong>of</strong> flow though its length is 509 km and has
a 22.300-square-kilometer catchment area. The plain had become scene for huge floods
and due to frequent changes <strong>of</strong> river beds numerous lakes, lagoons, meanders and
marshes are formed. The last flood had happened in 1932 changing Ceyhan's course
towards the south and the river started flowing in its current bed. The former riverbed
still keeps its form and though limited, freshwater is released to the lagoons through it
via a tap placed inside the riverbed. Ceyhan River, one <strong>of</strong> the 26 hydrologic basins <strong>of</strong>
<strong>Turkey</strong>, and its tributaries has been dammed for energy generation, irrigation, flood
last one Berke (2003) are the dams constructed on the river and its tributaries.
There are numerous lakes and lagoons within the site. They are the sub-components <strong>of</strong>
lagoon systems.
o each other with natural canals. These lakes
heavy evaporation. The lakes are getting filled rapidly because <strong>of</strong> sediment load by the
streams and canals, flowing from the north. The depth is 0--60
considered as separate lakes since they have slight separations;; though they indeed
compose one single system. The depth has decreased to 30-50 cm from 1.5-2 meters in
the past 20 years. The sands carried from the sand dunes by wind erosion has been
effective in siltation. Apart from the mentioned, there are many lakes in the site, not
shown on the maps. Lagoons used to be fed by the regular floods <strong>of</strong> Ceyhan River in the
past. Since the floods are prevented by the dams constructed on Ceyhan River and its
tributaries, freshwater feeding to the lagoons is also prevented. Currently the freswater
sources <strong>of</strong> the lagoons are precipitation water falling on the surface and the basin <strong>of</strong> the
lagoon, leaking effects and artesianic feeding.
The saltwater entrance into the lagoons happens via lagoon-sea links. The facts that the
total annual evaporation in the region is almost double <strong>of</strong> the annual precipitation
amount and the typical Mediterranean climate warm, wet winters and hot, dry
summers prevails in the region leads an increase in the salt concentration <strong>of</strong> the
lagoon.
during wet seasons. Many canals are opened for drainage and irrigation <strong>of</strong> the farm lands
located in or outside <strong>of</strong> the site.
In the areas close to the sea or lakes the underground water is salty and fresh or less
salty as it gets farther. Freshwater prevails through Ceyhan River's bed within the delta;;
saltwater becomes more dominant closer to the sea.
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