Updated document: Evaluation of the MUN beneficial use in Ag dominated water bodies

This is a message from the California Regional Water Quality Control Board, Central Valley (5).

Thank you to those who attended the last stakeholder meeting for the “Evaluation of the Municipal and Domestic Supply (MUN) Beneficial Use in Ag Dominated Surface Waters” project. The emphasis of the meeting last week was on the continued development of the proposed LIMITED-MUN beneficial use designation, as part of the Basin Planning effort to establish a region-wide MUN evaluation process in Ag dominated surface waters. The LIMITED-MUN beneficial use designation will also be the focus of an informational item we are bringing to the next Central Valley Water Board meeting at the end of July.

In preparation for this informational item, attached here an updated version of the LIMITED-MUN beneficial use designation planning document for your feedback and comments. This version incorporates additional suggestions for definitions and water quality objectives received at the stakeholder meeting. Some of the issues that were identified during the meeting include:  the use of “non-potable” in the definition of LIMITED-MUN, the use of “accumulation” and “natural background concentration” in a narrative objective; establishing applicable non-potable water quality criteria (existing non-potable water quality objectives are primarily focused on the use of reclaimed/recycled water); and the use of the antidegradation language in several of the narrative objective options. This document will be used to identify and communicate to the Board the preferred options for the definition and water quality objectives of the LIMITED-MUN beneficial use, so please review the material that is attached and send any comments and additional suggestions to alittlejohn@waterboards.ca.gov by the end of the day on Monday June 22, 2015.