Ambient Water Quality Monitoring Data

LDEQ collects surface water quality data in its Ambient Water Quality Monitoring Program as well as for other projects in water bodies across the state. Ambient water quality data, as well as other water project data, collected by LDEQ is available by accessing the LEAU Web Portal.

  • To locate the Ambient Water Quality Monitoring data click on “VIEW SITES” under “Ambient Water Quality.”
  • Water quality data for other LDEQ projects can be accessed under “Projects,” “Sites Map,” and “Mercury Initiative.”

Over 600 ambient water quality monitoring sites have been established since 1958 but not all sites are currently in use. In 1998, the department established a four-year rotating monitoring program in order to expand the coverage of its monitoring efforts. LDEQ collects ambient surface water data at approximately 125 sites across the state each month. In addition, 21 sites on 16 water bodies are monitored every month of every year as long-term trend sites in the ambient monitoring program. In addition to the ambient program, water quality data is also collected at various water bodies for a variety of specialized projects.

This water quality data is used for establishing water quality criteria or standards, assessment of conditions, and development of Total Maximum Daily Loads (TMDLs). TMDLs are one means of establishing water quality discharge permit limits and Nonpoint Source Pollution reduction recommendations for the protection and improvement of surface water quality in Louisiana.

Water quality data may also be obtained by contacting the LDEQ Public Records Group. For questions regarding the LDEQ Ambient Water Quality Monitoring Program, Mercury Initiative or other programs, please contact the Water Planning and Assessment Division.