Date of Award


Document Type


Degree Name

Master of Science in Earth and Environmental Sciences


Chemistry and Biochemistry

First Reader/Committee Chair

Noblet, James


The Santa Ana River (SAR) is the largest river in Southern California. The flow of the SAR begins in the San Bernardino Mountains and discharges into the Pacific Ocean at Huntington Beach. The SAR contains one of the most essential and rare biodiversity hotspots on earth. In order to protect the wildlife, and suit population demands, the SAR must meet the Clean Water Act (CWA) regulations. The SAR Reach 6 is the uppermost segment of the river, and is currently listed under the CWA 303(d) List for impaired water due to contamination of cadmium, copper, and lead from an unknown source based on limited data provided in 1997 by the San Bernardino County Flood Control District (SBCFCD). This project focused on confirming the contemporary occurrence and identifying the potential source(s) of Cd, Cu, and Pb by comparing new water sample data with that of previous studies The analysis of previous data identified an interesting correlation between high water hardness and elevated lead levels. The new results from this study suggest that there continues to be a source of these metals in the upper parts of Reach 6 of the SAR. Moreover, the limited data obtained in this study suggests that the source of the contamination is upstream to the northeast of the primary sampling site, possibly on private lands. Future, more comprehensive studies will be required to determine whether Reach 6 of the SAR should remain on the 303(d) list. Source identification if necessary, will be a further challenge.