Lake Büyükçekmece is a liman, formed at the point, where the river Karasudere flows into the Marmara Sea. Located in the south of Çatalca

Çatalca

Çatalca is a city and a rural district in Istanbul, Turkey. It is in Thrace, on the ridge between the Marmara and the Black Sea. Most people living in Çatalca are either farmers or those visiting vacation homes. Many families from Istanbul come to Çatalca during weekends to hike in the forests or...

 district west of Istanbul

Istanbul

Istanbul , historically known as Byzantium and Constantinople , is the largest city of Turkey. Istanbul metropolitan province had 13.26 million people living in it as of December, 2010, which is 18% of Turkey's population and the 3rd largest metropolitan area in Europe after London and...

, Turkey

Turkey

Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...

, it is used as a freshwater reservoir.

The lake's bar

Bar (landform)

A shoal, sandbar , or gravelbar is a somewhat linear landform within or extending into a body of water, typically composed of sand, silt or small pebbles. A spit or sandspit is a type of shoal...

 was reinforced in 1988 by a dam

Büyükçekmece Dam

Büyükçekmece Dam is a dam in Turkey. The development was backed by the Turkish State Hydraulic Works.-References:*, State Hydraulic Works , Retrieved December 16, 2009...

. The area of the lake is 28.47 km² (11 sq mi), it is 7 km (4.3 mi) long and 2 km (1.2 mi) wide. The maximum depth is 8.6 m (28.2 ft) following deepening works carried out by the State Hydraulic Works

State Hydraulic Works (Turkey)

The State Hydraulic Works is a state agency organized under the Ministry of Environment and Forestry of Turkey responsible for the utilization of country's all water resources...

.

The fluvial

Fluvial

Fluvial is used in geography and Earth science to refer to the processes associated with rivers and streams and the deposits and landforms created by them...

 lake developed as the flow of Karasudere, coming down from Çatalca region, was blocked by the sandbank it created. A reedy, light salty water lake exists between the Büyükçekmece Dam and the Marmara Sea. Another lake of liman type, the Küçükçekmece Lake, is located around 12 km (7.5 mi) east of Büyükçekmece Lake.

The number of fish species known in the lake has decreased from 30 in the past to 15 nowadays.

A historical, 635 m (2,083.3 ft) long and 7.17 m (23.5 ft) wide multiple arch bridge

Arch bridge

An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side...

, named after the Ottoman

Ottoman Empire

The Ottoman EmpireIt was usually referred to as the "Ottoman Empire", the "Turkish Empire", the "Ottoman Caliphate" or more commonly "Turkey" by its contemporaries...

 architect Mimar Sinan (1489-1588), spans the narrow opening at the bar connecting the lake to the sea.

At the northern shore of the lake, Istanbul Hezarfen Airfield

Istanbul Hezarfen Airfield

Istanbul Hezarfen Airfield is a privately owned airport for general aviation located in Çatalca district of Istanbul, Turkey. The facility, one of the four airports in Istanbul, is named after Hezârfen Ahmed Çelebi, an Ottoman scientist, who had crossed the Bosporus flying in the 17th century as...

is situated on a peninsula.