Northern Prairie Wildlife Research Center
Riparian Areas of South Dakota
Stream Banks - Riparian Foundations
Building a Riparian Area
When stream banks are resistant to the powers of waterflow, the channel tends
to be narrow and deep. That becomes the foundation of a stable riparian area.
- When floods occur, higher water speeds are slowed by streamside vegetation.
- Vegetation helps build stream banks and riparian areas.
- Vegetation helps keep streams flowing during dry periods.
|Streams and rivers flowing through riparian areas have three common
- the water in their channels has mass (or weight).
- the mass of water is dragged downhill under the influence of gravity.
- the water flows at some speed (or velocity).
||A simple doubling of the speed of a stream's flow allows it to erode
four times as much and to carry 64 times the amount of material. That's
Vegetation - The Roots of the Solution
||Streams and riparian areas are "glued" together by a diversity of
plants with strong root systems.
Streamside vegetation reduces the horsepower of a stream, slowing
water down through friction. A two-inch deep rootmat resists erosion
up to 20,000 times better than bare soil streambanks.
As the percentage of roots in stream banks increases, erosion decreases.
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