Practicum Project | 2010

Examining Marine Debris Along Los Angeles County Beaches: A qualitative and quanitative analysis

Students: Alisan Amrhein, Hui Yan Terri Chan, Jonathan Chang, Gabe Kiritz, Jaimie Lee, Karestine Nga, Sean O’Connor, Jaynel Santos

Client: Los Angeles Regional Water Quality Control Board

Advisor: Dr. Rebecca Shipe

This study evaluated qualitatively and quantitatively the patterns of marine debris distribution found on the following four L.A. County Beaches: Malibu-Surfrider Beach, Venice Beach, Dockweiler State Beach, and Redondo Beach. Evaluations were characterized according to beach topography, land use characteristics, type of debris, and original use of debris found at each focus area. Each study area represented a diverse set of features that we predicted might effect the amount and type of debris collected. The intent for choosing each study area lies in the set of features identified: gentle sloping foreshores, minimal vegetation, similar beach composition, recreational sites and diverse land usage in surrounding areas. Debris was collected, classified, and analyzed during the period between February 20, 2010 and April 11, 2010. Quadrants, 4x4m in size, were randomly sampled and the number of quadrants vary with beach size. All debris, over the size of 5mm, found in these quadrants were taken to the laboratory for further examination and classification. The highest debris load was noted on Dockweiler State Beach, and the amounts were generally correlated with precipitation. Plastics were found in abundance on all beaches, however, many pieces were degraded suggesting that they had originated in upstream waterways for a significant amount of time before accumulating onto the beaches. The original use of most debris items was associated with food and beverage. After careful analysis, proper correlations and recommendations were drafted to assist the L.A. Regional Water Quality Control Board in the creation and implementation of a Total Maximum Daily Load Regulation (TMDL) for beaches in Southern California.