The average annual discharge through the Innerste Dam is 60 million m³.

The Innerste is an earth-fill dam with multiple, external, asphaltic concrete layers.

In front of the upstream base of the dam is a shaft spillway (a flood overflow tower), into which also the bottom outlet is integrated.

From 2003 to 2005 the reservoir was completely emptied and renovated, especially the asphalt sealing and the bottom outlet.

Nevertheless, even when the Innerste Dam overflows, the level of retention significantly reduces and delays flooding.