underflow

Here the waters lost themselves for many feet in the underflow so common in this land of aimless, uncertain waterways.

It is filled to the brim with sand, however, and through the sand is an underflow.

In the wildest waters they say there is a calm underflow,—maybe the lad has found it and is glad to sleep.

From the area of water-bearing gravels found, it was proposed to tap the underflow water at the 630-m.

The general scheme for tapping this underflow was to drive a main gallery at the 560-m.