Distribution Of Fecal Indicator Bacteria In Flood Control Channels Of Huntington Beach, California

High levels of fecal indicator bacteria (FIB) consisting of total coliform (TC), E. coli (EC), and enterococci (ENT) bacteria indicate the presence of fecal contamination in the surf zone. Previous studies indicated possible tidal influence of flood control channels on the coastal water quality. As part of a class project, 14 undergraduate students, consisting of Chemical Engineering and Environmental Engineering majors, performed this study during rising (flood) and falling (ebb) tides, and showed the distribution of FIB in flood control channels. While the students were exposed to field work and laboratory procedures for the water quality, the results have important implications in the design of the diversion systems during dry weather. Introduction Once viewed as being a sub-set of civil or chemical engineering, the discipline of environmental engineering has established a status in its own right worldwide. The industry requires that new graduates have both increased knowledge in the field and capability to respond to public health and environmental protection issues. In order to improve teaching-learning process active and interactive participation of the students is preferred over traditional lecture-based teaching process. This type teaching style is found to be more appealing to students with diverse learning styles. In dry weather periods urban runoff generated by street cleaning, car washing and landscape irrigation has shown to contain high levels of FIB. Previous studies 7 indicated that urban runoff can be the source of elevated surf zone levels of FIB at Huntington State Beach and Huntington City Beach in California. Sanders et al. modeled tidal transport of urban runoff in flood control channels using the finite-volume method to understand the transport of pollutants toward the P ge 736.1 Proceedings of the 2002 American Society for Engineering Education Annual Conference & Exposition Copyright 2002, American Society for Engineering Education coastline. The goal of this study was to characterize FIB levels at various locations during neap and spring tides by exposing students to both fieldwork and laboratory procedures. Methods In Spring 2001 quarter at the University of California, Irvine, 14 undergraduate students, consisting of Chemical Engineering and Environmental Engineering majors, sampled and analyzed water samples at various locations shown in Figure 1. Due to intense work involved they were divided into groups of two to three students. Each group was responsible for sampling and analysis of the samples at a given sampling time. The sampling device designed by the students consisted of two 500-mL polypropylene bottles attached to a rope by a sample holder. At each station, two 500-mL water samples were collected in sterile polypropylene bottles eight times a day during neap (May 15, 2001) and spring (May 23, 2001) tides. For each bottle, salinity, pH, and turbidity of the sample were measured by temperature correction to 20C. 20 mL of the sample was analyzed for fecal indicator bacteria (TC, EC, ENT) using IDEXX Colilert (TC, EC) and Enterolert (ENT) tests performed in a 97 well Quanti-tray format. The experimental data were plotted on a grid with size of circles proportional to the measurements. Huntington Beach Channel 1: Adams 2: Atlanta 3: Newland 4: Magnolia Talbert Marsh 5: Brookhurst 6: Pacific Coast Highway Figure 1. Sampling sites in Huntington Beach, California during neap (May 15, 2001) and spring (May 23, 2001) tides. Eight times a day, samples were collected consecutively by driving from sampling site 1 to site 12. The samples were analyzed for salinity, pH, turbidity, and fecal indicator bacteria (TC, EC, and ENT). Talbert Channel 7: Hamilton 8: Atlanta 9: Indianapolis in front of the dam 10: Indianapolis behind the dam 11: Yorktown in front of the dam 12: Yorktown behind the dam 40.0