Chapter 3: Section 4 - High-Gradient Streams

PDF versionPDF version


In this section you will find materials that support the implementation of EarthComm, Section 4: High-Gradient Streams.

Learning Outcomes

  • Use a model to describe the characteristics of high-gradient streams.
  • Analyze data on a local topographic map to calculate the gradient of a stream in your community.
  • Analyze data for the Mississippi River System to explain the connection between stream gradient, elevation, and discharge.
  • Analyze data for a high-gradient stream in your community to explain the characteristics of its channel, floodplain, and streamflow.


  1. To find data on the discharge of rivers in the United States , visit the following web site:

    Real-Time Water Data for the Nation, USGS
    Identify your local river and find data on its discharge, drainage basin area, and stream velocity.

Inquiring Further

  1. To learn more about the Big Thompson, Colorado flood, visit the following web sites:

    The Big Thompson Canyon Floods of 1976 and 2013, USGS
    The Big Thompson Canyon Flood in 1976 was the worst natural disaster in Colorado's history. Learn about this event and the next deadly event caused by massive rainfall.

    Big Thompson Canyon, NASA
    Describes the events and conditions that led up to the Big Thompson Canyon flood.


To learn more about this topic, visit the following web sites:

Characteristics of High-Gradient Streams

Streams and Drainage Systems, Tulane University
Describes stream-flow dynamics, including shape, gradient, velocity, and discharge.

Nehalem River Watershed Assessment: Channel Habitat Typing, Portland State University
Provides information on the effects that different stream gradients can have on organisms in the stream.

Simple Protocol (Quantified) for Habitat Assessment of Streams, Australian River Authority
A simple protocol for the assessment of river conditions based on stream channel characteristics.

Physical Stream Type Classification, Pennsylvannia State Gov. Heritage Commision
Describes variables that influence biological habitat based on physical stream channel characteristics, including gradient. Also has a useful list of biological communities and their commonly associated physical stream types.