The DO criteria identify waters with DO problems and can form the basis for necessary reductions in nutrient levels. Saltwater DO criteria for coastal and estuarine waters will help states, territories, and authorized tribes develop and adopt DO water quality standards. Environmental planners can also use the approach to evaluate conditions under different management scenarios and make better decisions. Dissolved oxygen criteria apply to both continuous and cyclic low DO conditions. Summary of DO Criteria for Persistent Exposure.
Lines are lower bound limits on protective DO concentrations.
The chronic growth limit may be violated for a specific number of days provided the chronic larval recruitment limit is not violated. The approach for episodic or cyclic low DO conditions requires that the DO be directly measured over a daily cycle or that the daily DO cycle be estimated. Under the CWA, states, territories, and tribes must adopt water quality criteria to protect designated uses. This criteria document does not substitute for those provisions or regulations, nor is it a regulation. Risk managers can apply the criteria to other coastal waters if they can scientifically determine that their location-specific biological, physical, and water quality conditions are comparable to those of the Virginian Province.