News
Updated as of April 20, 2002.

Study Area
Lots of pictures, maps, and background info on our hydrology, ecology and environment, land and resources uses, and selected sites.

Studies and Surveys
Descriptions of our projects and studies.

Publications and Data

• Publications
• Hydrologic and Chemical Data
• Maps and Geographic (GIS) Data
• Ecological Data

Personnel and Links
Have a question? Talk to us, or find other online locations of Louisiana information.

Site Map
And accessibility features.

For more information on USGS activities in Louisiana and the Nation, please visit the following websites:

NAWQA Home
Louisiana District
Water Resources Division
U.S. Department of the Interior

The Nationwide NAWQA Design and Application in Southern Louisiana

The initial focus of the National Water Quality Assessment Program has been to determine the occurrence and distribution of many chemicals and compounds influencing water-quality conditions. The national study design for surface- and ground-waters focuses on water-quality conditions in streams using interrelated components -- surface-water studies, groundwater studies, bed-sediment and fish-tissue studies, and ecological studies. For an overview of how the national NAWQA program is organized, and a description of objectives and goals, please read "Design of the National Water-Quality Assessment Program: Occurrence and Distribution of Water-Quality Conditions, Circular 1112", or the Program Details. There is also a full list of methods and protocols that we use in our studies.

Water-column studies monitor physical and chemical characteristics, which include suspended sediment, major inorganic ions, nutrients, organic carbon, and dissolved pesticides, and their relation to hydrologic conditions, sources, and transport.

These studies examine surface-water chemistry and hydrology:

• Fixed Surface-water Sites - Monthly water sampling
• Herbicides and Nutrients in Streams of the Barataria-Terrebonne Basins
• Nutrients in Drainages of the North Shore of Lake Pontchartrain
• Mermentau Basin Water-quality and Ecology Study

Ground water studies focus on water-quality conditions in major aquifers, with emphasis on recently recharged ground water associated with recent and current human activities, by using study-unit surveys, land-use studies, and flowpath studies.

Land-use studies focus on recently recharged shallow aquifer systems so that the influences of land-use practices and natural conditions can be assessed. Typically, about 30 new observation wells are drilled at randomly selected sites within each land-use type and aquifer.

These studies examine groundwater chemistry:

• Chicot Aquifer Ground-water Survey
• Chicot Equivalent (Southern Hills) Aquifer Ground-water Survey
• Ground-water Quality in an Area of Rice Agriculture
• Ground-water Quality of an Urban Area (Lafayette, LA)

Collections of bed sediment and fish tissue trace the movement, degradation, and accumulation of contaminants in aquatic ecosystems. In particular, these surveys look for heavy metals and man-made chemicals such as pesticides, industrial solvents and products, and those from burning fuels or waste.

Ecological studies evaluate the relations among physical, chemical, and biological characteristics of streams. These surveys are done along a delineated stream reach and include a habitat assessment of the site and annual surveys of the fish, algal, and benthic invertebrate communities.

These studies characterize ecological communities:

• Contaminants in Bed Sediments and Fish Tissues
• Fixed Surface-water Sites - Ecological Characterization
• Mermentau Basin Water-quality and Ecology Study