Soan River

s of the Soan RiverThe Soan River drains much of the water of the Pothohar Plateau. It originates in the foothills of Patriata in Murree and supplies water to the Simly Dam, a reservoir for Islamabad. Near Pharwala Fort, Ling Nullah, following a relatively long course through Lehtrar and Kahuta, joins the Soan near Sihala on the southern side of village Gagri. The Islamabad Expressway crosses this stream near Sihala at the Kak Pul bridge. Two other streams, the Korang Nullah and the Lai Nullah, join the Soan just before and after the Soan Bridge, respectively. The Rawal Dam has been built on Korang Nullah. After following a path along a big curve, the stream reaches the proposed Kalabagh dam site close to Pir Piai where it falls into the Indus River. == Hydrology ==

The catchment area of Soan River is while its mean annual discharge at Makhad during the period 19602005 was , with a minimum and maximum discharge of and , respectively. However, a decreasing trend is observed in the mean annual discharge, owing to reduced rate of rainfall and construction of reservoirs in its catchment area. == History ==

Oldest evidence of human activity in Pakistan has been found in the Soan River Valley. The human activity in the Soan Valley is believed to have originated during the Stone Age. Here some of the earliest signs of pre-modern humans, known as Soanians, have been discovered during the excavations of prehistoric mounds. Some relics found in the Soan Valley during the excavation process are believed to have originated over 500,000 years ago, during the Stone Age. ==See also==