Two giant dams changed Europe’s second-longest river. Decades later, scientists found the Danube Delta was being starved of sediment

• The Danube does not arrive at the Black Sea as it once did.
• For thousands of years, the river carried enormous quantities of sediment towards its delta, steadily building and reshaping the low-lying landscape where river channels meet lagoons and the sea.
• That process changed after large-scale engineering works altered the river upstream.