GSA Connects 2022 meeting in Denver, Colorado

Paper No. 126-5
Presentation Time: 2:00 PM-6:00 PM

CALIFORNIA CAUTIONS: ALGAL INVESTIGATION OF INNER CABRILLO BEACH


SERRATO, Alyssa and HUGHES III, Richard, Geoscience Department, Crafton Hills College, 11711 Sand Canyon Road, Yucaipa, CA 92399

Harmful Algal Blooms (HABs) are an ecological disaster that result in the loss of millions of dollars annually in human health, economic opportunity, and recreation. Major health concerns are focused on the disruptions in the food chain that lead to massive bird and fish death along with fatal food born illnesses. Stagnant waters are prone to these disruptions, for they create eutrophic conditions allowing high cultivation of domoic acid releasing plankton and fecal indicating bacteria that exceed federal safety levels. Still freshwater bodies tend to be the most susceptible to these occurrences, but areas with minimal water flow such as enclosed beaches are also prone to HABs. Los Angeles Harbor’s Inner Cabrillo Beach in San Pedro is ranked among the most vulnerable.

Several hypotheses on how to mitigate conditions in this area have come about, including the removal or repurposing parts of the Long Beach Breakwater to permit better water flow, replacement of beach sand promoting better drainage, and the implementation of bird deterrent structures to reduce fecal indicating bacteria levels. However, studies show that removal or repurposing any or all of the breakwater would be expensive and a risk to businesses. Sand replacement and bird deterrent structures have helped alleviate bacterial cultivation, but the number of HABs is still high due to storm surges that fluctuate bacteria and nutrient levels, state protected eelgrass beds that promote bacterial growth, and the direction and temperature of the ocean currents. It is speculated that the very existence of HABs within the area is unpreventable but can be predicted. As a result, the direction of focus has shifted from prevention and mitigation to communication with the public, businesses, and cities to reduce public health cost.

Recent research has moved in this direction. USC researchers began a community HAB watch program in 2011 that provides affiliates the tools to collect data and report local HABs. At the state level the CA HAB bulletin was created to seek out real-time data on HAB locations across the California coast based on California Harmful Algae Risk Mapping (C-HARM) readings. At the federal level, NOAA, the National Oceanic and Atmospheric Administration, is developing public accessible forecasting and monitoring systems for California HABs.