[6] Nearly 4,760 km2 (1,840 sq mi) of arable land in the Şanlıurfa-Harran and Mardin-Ceylanpınar plains in upper Mesopotamia is being irrigated via gravity-flow with water diverted from the Atatürk Reservoir through the Şanlıurfa Tunnels system,[7] which consists of two parallel tunnels, each 26.4 km (16.4 mi) long and 7.62 m (25.0 ft) in diameter.

Irrigation expansion within the Harran plains also increased Southeastern Anatolia's cotton production from 164,000 to 400,000 metric tons in 2001, or nearly sixty percent.

[12] Atatürk Reservoir is an abundant source of food for local people and also provides opportunities for recreational fishing.

[14] Considering all aspects of fishery activities, the reservoir contributes in total US$15 million to GNP and generates employment for 1,600 people.

The young people in the region developed an interest in water sports and started to take part in international contests in the branches of sailing, rowing-canoeing, swimming and diving on the Atatürk Reservoir.

[22] Furthermore, International Atatürk Dam Sailing Competition takes place every year in October on the lake.

[23] With the forming of the reservoir lake, more than a hundred hamlets and villages were inundated and about 55,000 people were forced to relocate, many of them resettling in nearby communities.

[25] In 1989, the old town of Samosata (Samsat), capital of the ancient Commagene kingdom located in Adıyaman Province was flooded behind the Atatürk Dam.

Since the entire GAP area was home to early civilization of the Hittites and the site of Nevalı Çori, and therefore rich in terms of historical remains, the cultural heritage of the region was a concern.

[26] The early Neolithic settlement of Nevalı Çori, site of some of the world's most ancient known temples and monumental sculpture, was discovered during rescue excavations before the dam was completed.