What is "schmalwasser"

The Schmalwasser is a large heath stream on the southern edge of the Lüneburg Heath. The brook rises near Blickwedel, winds southwards, is joined from the left by the Räderbach and discharges into the Lutter in the village of Bargfeld (in the municipality of Eldingen).

The story Die Wasserstraße by Arno Schmidt (1964) is about a walk up the Schmalwasser.