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Section 404 of the Clean Water Act

Scientific Documents related to Wetlands and Aquatic Resources in the U.S.

National Wetlands Inventory Report

Report to Congress on the Status and Trends of Wetlands in the Conterminous United States 2004 to 2009 - The report provides the most recent and comprehensive estimates of the current status and trends of wetlands in the conterminous 48 United States on public and private lands.

National Resources Inventory Report

National Resources Inventory - The NRI is conducted by the U.S. Department of Agriculture's Natural Resources Conservation Service, in cooperation with the Iowa State University Statistical Laboratory. The NRI is a statistical survey of land use and natural resource conditions and trends on U.S. non-Federal lands, including wetlands.

Hydrogeomorphic (HGM) Approach for Assessing Wetland Functions

HGM Action Plan - Federal Register notice -Through the National Action Plan, the Army Corps of Engineers (Corps) is announcing the strategy the Corps and other Federal agencies will follow to implement the Hydrogeomorphic Approach for Assessing Wetland Functions (HGM Approach) through the development of regional guidebooks. The National Action Plan was developed by a National Interagency Implementation Team. For additional information on HGM, link to the Army Corps of Engineers Waterways Experiment Station Home Page.

Geographic Information Systems (GIS) Analysis of the Surface Drinking Water Provided by Intermittent, Ephemeral, and Headwater Streams in the U.S.

Drinking Water Analysis Relevant to Rapanos Decision is a GIS analysis aimed at illuminating dependence on intermittent, ephemeral, and headwater streams for water to supply public drinking water systems.

Field Operations Manual for Assessing the Hydrologic Permanence and Ecological Condition of Headwater Streams

EPA's Office of Research and Development published this manual of procedures used to assess the physical and biological characteristics of headwater streams.

Ecological and Hydrological Significance of Ephemeral and Intermittent Streams in the Arid and Semi-arid American Southwest

EPA's Office of Research and Development and the USDA Agricultural Research Service collaborated on the publication of this report. The report synthesizes current knowledge of the ecology and hydrology of ephemeral and intermittent streams in the Southwest.

Connectivity of Streams and Wetlands to Downstream Waters: A Review and Synthesis of the Scientific Evidence (Final Report)

This report represents the state-of-the-science on the connectivity and isolation of waters in the United States. It makes five major conclusions, that are drawn from a broad range of peer reviewed scientific literature.

Streamflow Duration Assessment Method for the Pacific Northwest

The Streamflow Duration Assessment Method (SDAM) for the Pacific Northwest is a scientific tool to provide a rapid assessment framework to distinguish between ephemeral, intermittent and perennial streams.