A database on water quality of the mississippi river

A water quality GIS/database has been developed for the Mississippi River within the state of Louisiana. Existing ambient water quality data (1.3 million records) and records of river stage and discharge for the river and its tributaries have been acquired from government agencies, industry, and research projects. Data were initially reviewed to validate information quality. They have been incorporated into an Oracle® database created to provide rapid data searches and retrieval of information through a menu‐format user interface. Descriptive information about sample collection and analysis methods are included, as well as government advisory criteria which provide ecological and human health perspectives to assist in data interpretation. GIS software utilizes electronic base maps which have been developed in Arc/Info® and ArcView® data formats to generate geographic displays and graphical representations of the data. Examples of the capabilities of the system are included for data on mercury, phosphates, and nitrates. The temporal trends in the concentrations of representative water quality parameters are tabulated for a selected segment of the river.