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Introduction How Rivers Run Stories Value Of A River What We Can Do
Quality of a River - Water Quality
Description (pg 2 of 2)

Because we satisfy our personal needs with water from a tap, we think of water as high in quality if it is clear and cold. Although that is a narrow measure of good water for human consumption, it is insufficient for measuring the overall quality of water in a stream.

Water quality in a stream can be assessed using biological indicators. Water quality is also determined by measuring a variety of physical and chemical properties, including:

  • Temperature
  • Dissolved oxygen
  • Alkalinity and pH
  • Nutrients
  • Sediment and turbidity
  • Contaminants

Each natural stream tends to exhibit and maintain a characteristic range of water quality measures, depending on such variables as hydrology and geomorphology (the availability of fine sediments and groundwater, for example). Water quality changes when human activities upset the basic conditions of the stream system. These changes are often harmful from the standpoint of stream life and system balance.


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Introduction
Flow
Shape
Connections
Quality
Description
Temperature
Oxygen
Alkalinity
Nutrients
Sediment
Contaminants
Status
Life
Summary
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