Translation of Narrative Criteria in Connecticut

Connecticut Water Quality Standards:

The Translation of Narrative Criteria in Connecticut

The CT Water Quality Standards (CT WQS) establish goals to restore and maintain the chemical, physical, and biological integrity of Connecticut (CT) surface waters and, wherever attainable, provide for the protection and propagation of fish, shellfish, and wildlife and for recreation in and on the water. 

There are two general types of criteria that are used to support designated and existing uses for CT surface waters: numeric and narrative criteria. Numeric criteria are concentration values of pollutants which if exceeded, will impact the ability of a waterbody to support the designated and existing uses. 

Narrative criteria, like numeric criteria, are also designed to support designated uses but narrative criteria instead provide a description of acceptable water quality conditions to support those uses. A means to translate those narrative criteria into numerical values or other conditions is needed so the narrative criteria can be implemented into environmental programs.

Documentation to support translation of various narrative standards is provided below.

Toxics

Nutrients