Tigris–Euphrates river system border. Since the 1960s and in the 1970s, when Turkey began the GAP project in earnest, water disputes have regularly occurred in addition to the associated dam's effects on the environment. In addition, Syrian and Iranian dam construction has also contributed to political tension within the basin, particularly during drought. The general climate of the region is subtropical, hot and arid. At the northern end of the Persian Gulf is the vast floodplain of the Euphrates, Tigris, and Karun Rivers, featuring huge permanent lakes, marshes, and forest. The aquatic vegetation includes reeds, rushes, and papyrus, which support numerous species. Areas
Duncan River was built the river served as the main navigation route into the valley, used by mining and logging industries. The route was navigable via Kootenay Lake as far as Bonner's Ferry, Idaho, on the Kootenai River. Duncan Dam was finished in 1967, the first of the three Canadian Columbia River Treaty dams to be built. Its purpose is to regulate flow into Kootenay Lake, in coordination with Libby Dam, to assure sufficient water flow for the Kootenay Canal and Corra Linn Dam projects. Duncan Dam does not produce any electricity. Duncan Lake, originally in length, is now long. Duncan River