2017 Technical Addendum Ambient Water Quality Criteria for Dissolved Oxygen, Water Clarity and Chlorophyll a for the Chesapeake Bay and Its Tidal Tributaries

Description

In April 2003, the U.S. Environmental Protection Agency (EPA) published, on behalf of its seven jurisdictional partners, the Ambient Water Quality Criteria for Dissolved Oxygen, Water Clarity and Chlorophyll a for the Chesapeake Bay and Its Tidal Tributaries, which was the foundation document defining Chesapeake Bay water quality criteria and recommended implementation procedures for monitoring and assessment. In October 2003, EPA published, on behalf of its seven jurisdictional partners, the Technical Support Document for Identification of Chesapeake Bay Designated Uses and Attainability, which defined the five tidal water designated uses to be protected through the published Chesapeake Bay water quality criteria: Migratory fish spawning and nursery habitat; open-water fish and shellfish habitat; deep-water seasonal fish and shellfish habitat; deep-channel seasonal refuge habitat; and shallow-water bay grass habitat.

Since April 2003, seven addendum documents have been published by EPA. Four addenda were published documenting detailed refinements to the criteria attainment and assessment procedures previously published in the original April 2003 Chesapeake Bay water quality criteria document. One addendum published Chesapeake Bay numerical chlorophyll a criteria. Three addenda addressed detailed issues involving further delineation of tidal water designated uses building from the original October 2003 tidal water designated uses document. Finally, one addendum documented the 92-segment Chesapeake Bay segmentation scheme after refinements to the Chesapeake Bay Program analytical segmentation schemes were documented building from the original U.S. EPA 2004 document. This 2017 addendum is the eighth addendum document developed through the Chesapeake Bay Program partnership and published by EPA. It provides previously undocumented features of the present procedures for assessing attainment of the Chesapeake Bay water quality criteria as well as refinements and clarifications to the previously published Chesapeake Bay water quality criteria assessment procedures.