geomorphology Geomorphology () is the scientific study of the origin and evolution of topographic and bathymetric features generated by physical, chemical or biological processes operating at or near Earth's surface. Geomorphologists seek to understand wh ...

, a stream head cut or simply head cut (alternately headcut) is an erosional feature of some intermittent and

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

stream A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a strea ...

s. Headcuts and headward erosion are hallmarks of unstable expanding drainage features such as actively eroding gullies. Headcuts are a type of knickpoint that, as the name indicates, occur at the head (upstream extent) of a channel. The knickpoint, where a head cut begins, can be as small as an overly-steep riffle zone or as a large as a

waterfall A waterfall is any point in a river or stream where water flows over a vertical drop or a series of steep drops. Waterfalls also occur where meltwater drops over the edge of a tabular iceberg or ice shelf. Waterfalls can be formed in seve ...

. When it is not flowing, the head cut will resemble a very short

cliff In geography and geology, a cliff or rock face is an area of Rock (geology), rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. ...

or bluff. A small

plunge pool A plunge pool (or plunge basin or waterfall lake) is a deep depression in a stream bed at the base of a waterfall or Shut-in (river), shut-in. It is created by the erosion, erosional forces of cascading water on the rocks at the formation's bas ...

may be present at the base of the head cut due to the high energy of falling water. As erosion of the knickpoint and the streambed continues, the head cut will migrate upstream. Groundwater seeps and springs are sometimes found along the face, sides, or base of a head cut.North Carolina Division of Water Quality, "Identification Methods for the Origins of Intermittent and Perennial Streams, Version 3.1", February 28, 2005 Channel incision is very common when head cuts are involved in stream morphology. In terms of stream restoration, head cuts are one of the most difficult challenges. Installing check dams or elevating the stream by filling the gully are common ways to mitigate up stream migration of the knickpoint. Another common way to control the knickpoint is by sloping the bank face by laying down fabric and rock.

References

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External links

* North Carolina Division of Water Qualit

Stream restoration problems
Geomorphology Fluvial landforms Erosion landforms