Streams & Rivers

Rivers and streams provide important ecological functions and services. These functions translate into the health, safety, and welfare of humans. By protecting, conserving, and minimizing direct physical alterations such as dams and vegetation clearing, these ecosystems provide substantial ecological functions, services, and value to society.

Threats and Impacts to Rivers and Riparian Habitat

• Disturbance and Equilibrium – natural or human disturbances to streams and rivers affect both the structure and ecological functions of these systems.
• Dams and Other Barriers – causing adverse effects to processes and block fish migration and movement.
• Impacts from Other Land Management Practices – Land use, watershed development, and resource management practices have caused both direct and secondary impacts to rivers and streams.

Hydrology

Studying, assessing and restoring rivers require an understanding of hydrology and other primary riverine features such as:

• Size-described in terms of stream order with first-order streams being the smallest, with no tributaries and generally in steeper landscapes.
• In-stream structure, including the location of the thalweg, pools, riffles, and runs, which define stream channel structure and affect the diversity of aquatic plants and animals.
• Riparian habitats bordering streams and rivers.
• Base flows, discharge, and storm flows. Watershed characteristics dictate flow conditions and the steepness of peak discharge.

For more information on restoring streams and rivers, click on the links below:

• Stream and River Restoration
• Stream and River Monitoring