Following the destruction of the Kakhovka HPP dam in June 2023, a critical public concern was the toxic contamination of the sediments left on the reservoir bed. To form our own perspective, the Ukrainian Nature Conservation Group (UNCG) joined the efforts to study these pollutants. We collected 119 soil samples representing various landscape and geochemical conditions, including bottom sediments, temporarily flooded zones, and dried-up areas. Laboratory analysis was conducted at Canterbury Christ Church University in the UK.
Over 70 years of operation, significant amounts of silt accumulated on the reservoir bed. The still-water body trapped a large volume of both organic and toxic pollutants, primarily from decades of industrial activity and mining in the region. The largest contributors were enterprises and industries in the cities of Zaporizhzhia, Dnipro, Kam’yanske, Nikopol, and Marhanets. When the reservoir was drained, some of this contaminated silt was moved and deposited on temporarily flooded areas and in the Dnieper-Bug Estuary (Dnipro-Buzkyi Lymаn). This effectively spread the polluted substrate over a much wider area than the original reservoir.
Our analysis of the soil samples revealed that 94% of them exceeded the maximum permissible concentrations (MPC) of heavy metals. The main contaminants are arsenic (As), lead (Pb), strontium (Sr), and zinc (Zn), with concentrations exceeding MPCs by 7 to 17 times. The high alkalinity of the environment (pH 7.0-8.6) prevents the migration of these toxic elements but facilitates their accumulation in the soil. This increases the risk of potentially toxic substances entering the food chain, which could have serious consequences for the temporarily flooded areas where people may eventually return and rebuild. The mobile forms of these metals are particularly concerning, as they can be actively absorbed by plants, posing a significant risk to the entire ecosystem.
The research results confirm that the former Kakhovka Reservoir territory is currently an ecological disaster zone. Of course, the situation was no better when the reservoir existed, but the use of its bed was not a concern then. Now, we can state that heavy metal contamination makes agricultural use of the former reservoir bed impossible. However, this contamination does not prevent the natural ecosystems from recovering. Soil-forming processes have already become active, especially in areas with higher organic content.
This is only the beginning of our research. To reduce future ecological risks, it is essential to study the impact of this contamination on biodiversity and to assess the effectiveness of phytoremediation—the process of using plants to clean up contaminated soil. We plan to continue our research and monitor how ecosystem restoration changes the environmental condition of this territory.
More detailed information will be available in the full text of our study.
The catastrophic destruction of the Kakhovka HPP dam was a direct result of a terrorist attack by russian troops, who deliberately blew up the structure. The rapid and uncontrolled release of water caused a major humanitarian and environmental disaster, leading to casualties and widespread destruction of ecosystems. This blatant criminal act constitutes an ecocide for which russian terrorists must be held accountable.
