site.btaDanube Ecosystems Face Growing Strain from Low Water Levels

Prolonged low water levels and high summer temperatures are straining the Danube’s ecosystems, the Regional Inspectorate of Environment and Water (RIEW) – Montana told BTA on Wednesday.

Low water levels and prolonged dry spells can alter habitat conditions, raise water temperatures and adversely affect individual species and ecosystems. Riparian and wetland areas are particularly sensitive and play an essential role in preserving biodiversity along the Danube, experts from the inspectorate said.

“The Danube is not only a major European waterway but also one of Northwestern Bulgaria’s most important natural systems. Changes in its condition must therefore be closely monitored and assessed not only as an environmental issue, but also in terms of the entire region’s sustainable development,” RIEW Director for Montana Svetoslav Iliev said. Several Natura 2000 protected areas along the Danube lie within the Montana and Vidin regions, which fall under the inspectorate’s jurisdiction, and preserve valuable natural habitats and species, Iliev noted. There is currently no evidence that the low water levels have caused irreversible changes to the river ecosystem. However, if the river remains at very low levels for an extended period, pressure on individual habitats and species could increase, Iliev added.

Iliev said the Montana inspectorate’s work extends beyond regulatory oversight. Its other core responsibilities include understanding and monitoring processes in natural systems and informing the public about changes in those ecosystems. The aim is to preserve Northwestern Bulgaria’s natural capital. “Protected nature is a resource and a prerequisite for the region’s long-term development,” Iliev added.

On July 7, 2026, six shallow stretches near Somovit, Belene, Batin, Svishtov and Vardim disrupted navigation along the Bulgarian section of the Danube and prompted restrictions on vessel draught. The river stood 9 centimetres below the reference zero mark near Ruse.

On July 14, 2026, a state of emergency was declared at Srebarna Nature Reserve after the lake fell to about 80 centimetres, nearly one metre below the seasonal optimum. The Danube remained too low to replenish the reserve naturally, prompting emergency pumping. No major damage to its flora or fauna was detected at the time, but experts warned that prolonged drought and high temperatures could lower oxygen levels and threaten the ecosystem.