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Introduction How Rivers Run Stories Value Of A River What We Can Do
Shape of a River - Geomorphology
Sediment

Many alluvial streams (those winding through beds of unconsolidated sediment rather than bedrock) flow in dynamic equilibrium, in which sediment load equals its transport capacity. In other words, healthy streams are able to carry a certain amount of sediment over time in a sustainable balance.

With the addition of excessive sediment, such as soil erosion from farmland, the stream will deposit excess sediment in the channel as riffles, bars, or islands. A dramatic reduction in sediment, such as construction of a dam that traps sediment, will cause the downstream channel to enlarge by widening and down cutting.

Long-term changes in the pattern or volume of discharge (tributaries) will change the amount of sediment carried by the river, altering channel width and depth.

Disruptions to this natural relationship occur through our land use practices and through direct disruptions to the channel itself.

Luther Aadland
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Sediment flow defines habitat

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Luther Aadland
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Dams change flow of sediment & nutrients

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Introduction
Flow
Shape
Description
Variables
Bankfull flows
Classification
Sediment
Patterns
Slope
Habitat
Change
Consequences
Stories
Connections
Quality
Life
Summary
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