WHAT IS A HEALTHY RIVER?
A river is a corridor through which ground and surface water, sediment, and debris move through a valley. The South Arkansas River, like so many rivers, has become simplified over time since European settlers and their descendants first arrived in our valley. The rivers and creeks that we see in our community today - the often single channel of open water and thin row of cottonwood trees lining the bank - is a gross reduction from what existed here for millennia. The manipulation of the river into one channel is a modern construct that is unnatural and unhealthy.
Understanding the river as a corridor allows for a holistic approach that encompasses the entire ecosystem rather than just the channel. Maintaining the river’s natural corridor width and allowing natural river processes to unfold (such as erosion and the deposition of sediment) supports the long-term health of the river and its surroundings.
A paper recently published by a global coalition of 37 authors from 28 organizations offers a definitive framework for understanding and supporting the restoration of our rivers. Principles of Riverscape Health distills decades of riverscape science into a clear, pragmatic set of principles that can guide policy, restoration, and conservation.
The paper offers three biogeomorphically focused principles of riverscape health.
Healthy riverscapes have:
space to interact within their valley bottom;
natural flow, sediment, and vegetation regimes appropriate to the biophysical setting and river type; and
structural forcing to support diversity and that creates varied residence times for water, sediment, and vegetation.
Figure from a 2024 paper illustrating a simplified river corridor (such as has been created even with “river restoration” practices in the South Arkansas corridor) and the potential that the river corridor has when given space and fed its natural biotic drivers (wood, vegetation, and beaver).
Marshall, A., Wohl, E., Iskin, E., & Zeller, L. (2024). Interactions of Logjams, Channel Dynamics, and Geomorphic Heterogeneity Within a River Corridor. Water Resources Research, 60(6), e2023WR036512. https://doi.org/10.1029/2023WR036512
