Sefidrood River is the most important river in Southern Caspian Sea area. Sefidrood is devised to two main rivers of Ghezelozan and Shahrood. The main basin of river passes from 11 provinces of Iran that 8 of them have majority. It originates from Kurdistan and Azerbaijan parts of Zagros Mountains in the west and Alborz Mountains in the east. They crosscut each other behind Sefidrood Dam (Manjil dam) in Gilan Province and meet Caspian Sea in Kiyashahr delta and lagoon (Bujagh lagoon). Aboriginals of Gilan and adjacent areas name the river “Espiroo”, means white river and Sefidrood actually is the Persian translated version of the river. According to information released by Iranian Water Management Company in winter 2009, 68 dams are in the net, 13 dams are constructing and 59 dams are studding. Updated information in September 2010 indicated 69, 16 and 62 dams respectively.

According to 40 years information (1967-2006) average annual discharge of the river is about 1760 million cubic meters. Unfortunately each of the provinces had a plan to construct dam without an integrated water recourses management (IWRM) plan for the basin that will affect northern parts of the river that are located in downstream of great Sefidrood watershed socially and environmentally severely.