As those above the surface face a lingering drought threat, Turkey seeks to increase the number of underground dams to hold water in the face of a climate crisis and swelling population
Located in a semi-arid climate zone and water-stressed, Turkey aims to take more steps for efficient use of its limited water resources, as a climate crisis threatens the country of more than 83 million people.
Dry seasons have been prolonged further in the country and started affecting wider areas, while their impact is being felt by more people. Boosting water supplies and curbing the demand are essential in this new era.
The State Hydraulics Works (DSI), a public agency, is at the forefront of efforts to boost the supplies, with new dams, hydroelectricity plants and reservoirs. Below the surface, they work on underground dams, as part of an action plan by the Ministry of Agriculture and Forestry for "artificially improving water sources." So far, 41 projects were launched for underground dams in the provinces of Izmir, Manisa, Çankırı, Konya, Bursa, Eskişehir, Antalya, Kütahya, Balıkesir, Nevşehir, Kayseri, Niğde, Malatya and Kayseri. Some are completed and others are under construction. By 2023, the government plans to complete the construction of some 200 underground dams.
Underground dams help to vacuum rainwater below the surface to increase the level of underground water and protect its quality and amount. Though they cannot be built everywhere as they need appropriate geographic and topographic conditions to store water, they have the double benefit of storing water both above and below the surface. They are also cheaper in terms of construction and land expropriation costs. Furthermore, they provide lower water evaporation rates compared to surface dams. Their construction focus on alluvial-based valleys and they can meet the drinking water and irrigation needs of small villages and towns around them.
Adem Sömer, a DSI official in the western province of Izmir, told Anadolu Agency (AA) Saturday that dams were essential for efficient use of water "going to waste." He said: "Underground water has strategic importance for us as a partial amount of drinking water supplies are from underground water. We run a series of probes and surveys before the construction and check whether the soil has an alluvial basis. This basis is critical for collecting water. An impermeable layer is constructed first to accumulate water. Water accumulated here is transferred to storage units with the aid of probes or a pooling system."
Sömer said they completed the construction of 10 underground dams in Izmir, Manisa and Uşak and they had six more planned. "Later this year, an underground dam with a capacity of accumulating 55,000 cubic meters of water will be completed in the Kiraz district of Izmir. It will provide up to 150,000 cubic meters of water yearly. It will primarily address irrigation demand in the Küçük Menderes delta where the agricultural activity is high. For instance, farmers will be able to irrigate 410 decares (101.31 acres) of land in nearby Suludere village with water provided from this dam only," he said.
Sömer said farmers had to turn to wells for irrigation in the past and it seriously depleted underground water levels. "You would have drill water wells for about 45 meters (147.64 feet) to find water about a decade ago but now you have to dig for up to 100 meters before any sign of water. We need to sustain underground water levels," he said. Sömer pointed out that an underground dam in Izmir’s Tire supplied some 6 million cubic meters of water below the surface and that underground water levels have reached nearly 10 meters depth thanks to the dam.
Experts say climate change coupled with the misuse of water resources has led to a water scarcity problem in Turkey. The country was on alert after a lengthy dry spell in winter prompted concerns of water shortage, especially for the metropolis Istanbul. The winter precipitation alleviated concerns, but the risk lingers in case of future droughts. Authorities readied several plans, and President Recep Tayyip Erdoğan assured the public in March that they already had action plans ready for water management up until 2071.