How do groundwater and rain contribute to the Volga River’s flow?

The Volga River relies on multiple water sources to maintain its flow. While snowmelt is the primary contributor, accounting for 60 percent of the river's annual discharge, groundwater and rain also play significant roles in its hydrology.1

• Underground water: This source accounts for 30 percent of the Volga’s annual discharge, providing a consistent base flow to the river system.1
• Rainwater: Precipitation contributes 10 percent of the river's annual discharge.1

The river's natural regime is characterized by high spring floods, largely driven by the seasonal thaw, followed by a summer low. While the basin experiences varying levels of annual rainfall—ranging from 25 inches in the northwest to 12 inches in the southeast—the river's overall discharge is heavily influenced by these combined inputs of snow, groundwater, and rain.123