to the Orange County Nitrogen and Selenium Management Program (NSMP) web
site. The NSMP is a multi-year work effort to comply with the requirements
of NPDES Permits (Order No. R8-2004-0021, R8-2007-0041, R8-2009-0045, and R8-2005-0079) and subsequent Time Schedule Orders (Order Nos. R8-2009-0069 and R8-2009-0070)
issued by the Santa Ana Regional Water Quality Control Board (Regional Board) for the Newport
Bay watershed in central Orange County, California (see Orange County Vicinity Map). Studies have found
that ambient groundwater concentrations in the watershed frequently exceed
numeric limits for selenium set in the permits, and because the feasibility
of currently established technologies for reducing selenium in short-term
groundwater discharges has not been proven, the NSMP's initial work focused
on better understanding selenium impacts and potential treatment methods.
Nitrogen issues were also addressed and will support re-evaluation of the existing
Total Maximum Daily Load (TMDL) for nitrogen.
The NSMP conducted its initial 5-year work effort in accordance with milestones set in the NPDES Permits. The work was coordinated with the NSMP Working Group consisting of staff level technical representatives of watershed stakeholders that include state, county, and city agencies, water districts, and private entities that have agreed to fund and implement a work plan to address selenium and nitrogen groundwater-related inflows in the Newport Bay watershed. The result was the development of many technical work products available in the NSMP Library page of this web site.
Following issuance of the Time Schedule Orders, the NSMP has focused on the development and approval of a Best Management Practices (BMP) Strategic Plan for the Santa Ana-Delhi and San Diego Creek Sub-Watersheds and a Selenium Regional Monitoring Plan required by the Time Schedule Orders. Both were approved by Santa Ana Regional Water Quality Control Board on December 5, 2013. The core of initial BMP implementation will be the construction of two major projects to divert selenium-laden water from the Peters Canyon Wash and Santa Ana-Delhi Channel areas to the sanitary sewer. The projects, collectively, will remove 170 pounds of selenium a year from the watershed as well as 33,000 pounds of nitrogen. Additional implementation efforts are also planned by the City of Newport Beach for the Big Canyon Wash Sub-Watershed.
The NSMP is also working with the Regional Board to revise the existing TMDLs for selenium in 2014 based on the new information acquired from the multiple NSMP studies. An initial series of workshops is planned for early 2014 with information provided on the Public Involvement page of this web site. Please visit the Newport Bay Selenium TMDL webpage on the Regional Board website for more information.