The Louisiana Department of Environmental Quality collects ambient surface water data at approximately 125 sites across the state each month. This 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.
Over 600 monitoring sites have been established since 1958 but not all sites are currently in use. Data has been collected at some of these sites since the inception of the program; however, most sites were established more recently. In 1998 the department established a four-year rotating monitoring program in order to expand the coverage of our monitoring efforts. Under this plan approximately 125 sites are selected each 12 month period (October-September) for monitoring once a month. In addition, 21 sites on 16 water bodies are monitored every month of every year as long-term trend sites.
The public may also obtain the data by contacting Public Records. Please provide Public Records with site numbers obtained from Ambient Water Quality Monitoring Sites and parameters of interest from Ambient Water Quality Parameters. For questions regarding Louisiana's ambient water quality monitoring program please contact the Water Planning and Assessment Division, Water Quality Standards and Assessment Section.