Protecting Newport Bay Top Priority for UC Irvine Engineers

The County of Orange and the Santa Ana Regional Water Quality Control Board have granted $800,000 to researchers at the University of California, Irvine to study the relative influence of anthropogenic and natural processes on fecal pollution in Newport Bay. The second largest embayment in Southern California, Newport Bay is a popular epicenter for recreational sports and beach activities in Orange County, while also housing a state ecological reserve, which provides refuge and breeding grounds for a number of threatened and endangered species.  The study will enable coastal zone managers to reduce the frequency of beach and shellfish harvesting closures in the area.

The project, which began in January 2006 and will continue over the next 12 months, reflects the priorities of the Proposition 13 Coastal Nonpoint Source Pollution Control Program, and provides the County of Orange comprehensive resources for monitoring, collecting and analyzing ambient water quality in Newport Bay.

Stanley B. Grant, professor and chair of the Chemical Engineering and Materials Science department, together with Sunny C. Jiang and Brett F. Sanders, associate professors of civil and environmental engineering, are working to quantify urban and natural sources which contribute to the fecal indicator bacterial (FIB) impairment in Newport Bay, while developing a source management plan that specifically targets the reduction of fecal bacteria entering from priority sources, such as urban run-off and treated wastewater.

The Environmental Protection Agency and the Santa Ana Regional Water Quality Control Board have adopted bay Total Maximum Daily Loads (TMDLs) to monitor and remediate impairments for fecal coliform, nutrients, sediment, and toxic pollutants in the water.

Potential fecal bacteria sources in Newport Bay include urban run-off and sewage, as well as bird feces and sediment re-growth, which can lead to an increased public health risk in the water, causing symptoms such as abdominal discomfort and bowel problems, as well as skin irritations.

“Water quality in the Bay is threatened by numerous pollutant sources that impact the Bay directly, or through the tributaries of its watershed,” said Grant.  “Our source management plan will provide a framework in which the local community can progressively achieve compliance with bacterial water quality, while also addressing the beneficial use objectives within the timelines outlined in the Bay’s TMDL.”

Recognizing the complexity of creating an efficient and accurate management system, Grant’s research team has developed an approach that involves intense data collection and analyses to quantify the impacts of specific sources of fecal coliform in Newport Bay.  Karen McLaughlin, a postdoctoral researcher, manages the project’s field studies, and closely monitors the FIB concentrations and physical characteristics of the Bay, along with a number of UC Irvine graduate and undergraduate researchers. 

“Our students have the excellent opportunity to participate in this field study by contributing to the collection and analysis of water and sediment samples on a weekly basis,” McLaughlin said.  “We combine data from traditional point measurements of FIB and nutrients, physical measurements of tidal flow and stratification in the Bay, and advanced molecular approaches for fingerprinting the fecal bacteria to identify the sources and life cycles of bacteria in the Bay.”

Some management considerations for controlling urban bacterial sources include the diversion of urban run-off, the replacement of aging sewage collection systems, and potentially changing boat “wash-down” procedures to prevent harmful contamination in the water.  However, if the fecal bacteria are from natural sources, such as bird feces and sediment re-growth, management controls may not be appropriate.

Ultimately, the plan will recommend corrective measures for Newport Bay, provide cost considerations for action measures, and develop a phased implementation plan for best management practices and control efforts.  All recommendations will directly relate to the goals and timeframes designated by the fecal coliform TMDL, and will facilitate TMDL compliance.

“Our main project goals are to advance the overall awareness of Newport Bay’s water quality, as well as provide county and state officials with the primary data needed to make informed decisions about how to best manage this important and beautiful resource,” Grant said.