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Water: Polluted Runoff

National Management Measures to Control Nonpoint Source Pollution from Hydromodification - July 2007

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July 2007

The primary goal of this guidance document is to provide technical assistance to states, territories, tribes, and the public for managing hydromodification activities and reducing associated NPS pollution of surface and ground water. The document describes examples of the implementation of practices that can be used to reduce NPS pollution from activities associated with channelization and channel modification, dams, and streambank and shoreline erosion.

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What YOU can do!

What's the problem?

Hydromodification is one of the leading sources of impairment in streams, lakes, estuaries, aquifers, and other waterbodies in the United States. Three major types of hydromodification activities

  1. channelization and channel modification
  2. dams
  3. streambank and shoreline erosion

change a waterbody's physical structure as well as its natural function. These changes can cause problems such as changes in flow, increased sedimentation, higher water temperature, lower dissolved oxygen, degradation of aquatic habitat structure, loss of fish and other aquatic populations, and decreased water quality. It is important to properly manage hydromodification activities to reduce nonpoint source pollution in surface and ground water.

What kind of pollution is impairing our Nation's waterbodies?

Leading causes of impairment to our Nation's waterbodies from hydromodification activities include nutrients, metals, hydrocarbons, bacteria, pesticides, and other constituents.

What is EPA doing about it today?

Part of our job is to keep streams, lakes, estuaries, aquifers, and other waterbodies from becoming polluted. We developed this free guide to help with this task.

Is this a regulatory action?

No. Use of the information in the guidance will be voluntary, though many states have requirements for managing hydromodifcation of streams, lakes, and other bodies of water. Check with your state for additional information.

Why should I protect water quality?

Sediment decreases water quality for fish and other stream animals and plants. Even if the water appears clear, some sediment remains. Oxygen-depleting substances and excess nutrients can be harmful to aquatic life and plants, sometimes causing algal blooms or fish kills. Pathogens and metals can also be harmful to aquatic life and human health, causing health problems and sometimes death.

What are other organizations doing about it?

Some states and other agencies have published similar guides. Check with your state department of environmental quality, department of agriculture, or the department of natural resources for assistance on hydromodification issues.

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What YOU Can Do!
What can I do about it?

Use the final guidance and the techniques it describes.

You can also learn more at the following sites:

How do I know whether the guidance will be helpful to me?

Check the table of contents and the overview, and skim a few chapters. Because the guidance is free, there's no cost to you to look at it. If you are interested in protecting and/or restoring waterbodies that are impacted by hyromodification, the guidance can help you better protect water quality.

Where can I get a copy of the guidance?

You can get more information about the guidance (EPA 841-B-07-002) or download the document (in PDF format) from Publications and Information Resources. Copies of the complete document can also be obtained by request from Chris Solloway at the above address, by e-mail (Solloway.Chris@epa.gov), or by calling (202) 566-1202.

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The Guidance

Note:The full Guidance document is a very large file that may take a long time to download. The individual parts (chapters and other divisions) of the full document are much smaller files that will open quicker. Opening the smaller files is the recommended viewing method.


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