Developing Numeric Nutrient Criteria for Mississippi's Waters

MDEQ is actively working to develop numeric nutrient criteria for Mississippi’s various water body types. MDEQ’s mission is to develop scientifically defensible criteria that are appropriate and protective of Mississippi’s waters. The criteria for each water body type will be coordinated with other water body types to ensure consistency across the state and provide protection from potential downstream impacts. Mississippi’s Nutrient Criteria Development Plan can be read by clicking here.

The Criteria Development Process

Mississippi is applying the process outlined in federal guidance for numeric nutrient criteria development for each water body type including (1) streams, (2) lakes and reservoirs, and (3) coastal and estuarine waters.

According to the criteria development guidance, the four basic elements of the process are:

    • Selecting variables and assembling high quality data
    • Classifying waterbodies (to reduce variability due to natural differences in nutrient concentrations)
    • Analyzing data using a multiple lines of evidence approach (distribution, stressor-response, mechanistic modeling, and scientific literature)
    • Deriving criteria

A Science-Based, Transparent Process

Mississippi is committed to a scientifically rigorous, defensible, and transparent process for conducting this analysis. To support this effort, MDEQ has assembled the Mississippi Nutrient Technical Advisory Group (TAG) to review and guide the process detailed above for each waterbody type. Click here for more detail on the Mississippi Nutrient TAG.

MDEQ is also conducting a series of stakeholder update sessions to communicate progress towards numeric criteria development and to receive feedback that will be considered by MDEQ and the TAG as the analytical tasks are performed. Click here for more detail on the Stakeholder Outreach efforts.

Lastly, MDEQ has developed and here makes available the technical support documentation on the analyses conducted to date in support of numeric nutrient criteria development.

Lakes/Reservoirs:

Streams/Rivers: Coastal/Estuarine: Delta Waters:
    • Analysis in Progress