Russian forces damaged the dam holding the Kurakhove Reservoir in Donetsk Oblast on Nov. 11, Governor Vadym Filashkin reported.
Filashkin's statement came after multiple reports of the dam being attacked near the village of Stari Terny, some 25 kilometers (15 miles) from the embattled town of Kurakhove.
The Kurakhove Reservoir is located on the Vovcha River, with its source near the village of Progress.
"This attack potentially threatens residents of settlements on the Vovcha River, both in Donetsk and Dnipropetrovsk oblasts," Filashkin said.
It's not the first time a critical dam was hit during the full-scale war.
Russia destroyed the occupied Kakhovka dam in Ukraine's Kherson Oblast in June 2023, unleashing massive floods and an environmental and humanitarian disaster across southern Ukraine.
Russian forces also damaged the dams and the adjacent hydroelectric power plants in Kyiv and Zaporizhzhia during mass aerial attacks against energy infrastructure.
According to the governor, the water level in the river within near Velyka Novosilka rose by 1.2 meters as of 4 p.m. local time. No homes have been flooded, he added.
Russian pro-war Telegram channels blame Ukraine for destroying the dam. The Ukrainian military has not commented on these claims.
Roman Padun, head of the Kurakhove city military administration, told Suspilne that authorities cannot check the scale of damage to the dam and inspect it due to constant attacks.
Russia is carrying out intense attacks in multiple sections of the eastern front, with attempts to break through Ukraine's defenses in Donetsk Oblast toward the towns of Kurakhove and Pokrovsk.
There is a threat of Kurakhove being encircled, Nazar Voitenkov, an acting spokesperson for Ukraine's 33rd Separate Mechanized Brigade, told Radio Free Europe/Radio Liberty (RFE/RL) on Nov. 5.