Located in Iran, Urmia was the largest lake in the Middle East and the 6th largest saltwater lake in the world. The water levels of the lake have been in decline since 1995. According to academics, it has been declining approximately 44.3 cm each year from 1995 to 2009. The lake surface area of 5,000 square km in 1997 shrunk to one tenth of that to 500 square km in 2013. By 2017 Lake Urmia had shrunk to only 10% of its original size (1972) due to multiple causes. Academics concluded that the shrinkage of Lake Urmia is anoutcome of human interventions rather than just a meteorological anomaly. Persistent drought (climate change) contributed to the shrinkage, while other causes were human interventions such as the construction of dams on the 13 rivers feeding the lake, or the pumping of groundwater from the areas adjacent the water body. Research has demonstrated that the crisis was not caused primarily by climate change, since the lake has survived many severe droughts in the past. Reduced river discharge is regarded as the main cause of the shrinkage of Lake Urmia. In the past three decades, Iran has profiled itself as the largest dam-constructor in the world. 70 dams were constructed on the rivers feeding Lake Urmia, diverting river water for irrigation to expand the Iranian agricultural industry, which saw an increase in demand. Irrigated areas in the Urmia Basin were 158 523 hectares in 1979, but had grown nearly three times and reached 450 000 hectares by 2011, supplied by the rivers of Zarrineh Rood, Mahabad and Shahr Chye, which feed the lake. Water was also transferred via pipeline from the river of Zarrineh Rood to Tabriz. These water infrastructures greatly diminished water flows to the lake. Additionally, more than 24,000 wells were illegally dug by villagers around the northwest region, further increasing the demise of Lake Urmia. The decline in water levels can be attributed as well to the construction of a 15km causeway crossing the lake, constructed in 2008. This embankment has only a small opening of 1.2km, which effectively divided the lake in northern and southern sub-basins and impeded the natural circulation of water and sediments. As a result, salinity levels were 60% higher in the northern basin.
As a result, the lake started to dry up and surrounding areas were damaged. It was possible to walk across the entire length of Lake Urmia which was turned into an immense desert of salt. The lack of water lead to a loss of biodiversity, as the habitat of more than 210 birds was destroyed. Desertification could potentially seep into the groundwater of the region, as the salt of the (former) lake is exposed. Such increased salinity has had an effect on the local agricultural sector as well. Salt storms have decreased the productivity of agricultural lands surrounding Lake Urmia, forcing the migration of farmers. Poor air, land and water quality have resulted in serious health effects on the local population. Populations around the lake are not equally vulnerable. As argued by Maya Zenko (2019) ethnic politics in Iran have undermined the Kurdish population around the lake but not so much the Azeri.
In recent years, the Iranian government has aimed to restore the lake, mostly focusing on increasing the inflow of the lake. Construction of further dams was halted, and water consumption is increasingly be regulated. The lake is being restored via water transfers, for instance from the Lesser Zab (a transboundary tributary of the Tigris River). Although this is the only option available to restore Lake Urmia, such water transfers produce harmful ecological and socio-economic side effects. Further sustainable practices are required to restore the lake, in particular the water demand will have to stabilize in all sectors. As a result of the Iranian government, internationalorganizations and NGOs, Lake Urmia was restored to 3,080 square km in early 2020. UNDP reported in April 2020 that through engagement with local communities, the area of Lake Urmia saw a reduction of water use by 25% and increasing irrigation efficiency by almost 42%.