natural depression
depression ***

The most common is the valley pond, which takes advantage of the natural topographical depression in the ground.

The lake is part of a natural depression and is fed by water by channel.

In the past, at the location of the lake, there was a natural depression where water used to accumulate.

In developed areas, natural depressions where storm water would pool, are filled in.

They were constructed in natural depressions on plateaus at varying levels.

The street is set in a natural depression and is shielded from the road by tall evergreens.

He was looking down into a natural depression, a bowl in the ground surrounded by an almost perfectly circular hill.

The lakes were originally a series of natural depressions that filled during floods.

Another is that the area contains a natural depression.

It lies in and waters a great natural depression called Al Fayum.