Schwienau (river)

Schwienau is a river of Lower Saxony, Germany. It is a left tributary of the Gerdau.

The Schwienau is 19 km long. It rises in the Weidebruch north of Brockhöfe near Wriedel. Initially the Schwienau flows through near-natural grassland landscape. After 2.5 km it has been straightened and directed past a pumping station. It discharges north of Groß Süstedt (a district of the municipality Gerdau) into the river Gerdau.

The Schwienau has been artificially straightened throughout much of its route and rarely flows in its natural channel. The banks either side are mainly used for agriculture. Only at Wriedel and east of it the river runs through small woods and untended heath. Its fluvial sediment consists mainly of sand and mud. This affords a habitat particularly for leeches, snails and shrimp-like animals called scuds. Its water is generally only moderately contaminated.