Maharlu Lake is located at 18km of south-east of Shiraz at an altitude of 1560 meters above the sea level and it is one of the tourist and resorts areas due to the proximity to the metropolitan city of Shiraz. This lake is supplied by three rivers, Khoshk, Hamzeh, and Sarvestan and also surrounding mountains runoff. This lake is 28 km long, 10 to 15 km wide and does not have a way to the open sea. Since the rate of evaporation in Maharlu Lake is high, salt covers a layer of it and water is only in the northern and central parts of it with very little depth and high salinity.
One of the interesting phenomena of this lake is the phenomenon of red tide. Red tides are a type of algae that are resistant to salt and when salinity rises, they growth more. The excessive proliferation of these organisms causes increasing the density of algae and place in a layer mode which prevents the air exchange and finally reduction of oxygen to water. In this condition, they produce some of the toxic organisms that are a potential risk for aquatic and hence, they endanger the aquatic and animals life that are adjacent the lake.
Maximum depth of this lake is 3meters so its amount of evaporation is high and this cause a part of lake bed to be covered with a layer of salt, of course the existence of chalky sediments of sachun formation and two salt domes in the east of the lake have considerably effect on its extreme saltiness.
Maharlu lake is a syncline-like subsidence with north west – south east trend and young and seismic sarvestan fault passes through it. It seems that this fault movements, especially in Late Pleistocene, has cause of syncline-like subsidence.
Image is looking to the East. In this Image, part of Maharlu lake, Shiraz-Goshnekan road, Lake Coastal Plain, Limestone mountains overlooking the lake (Asmari formation) and some abandoned buildings are seen.