Distribution Of Fecal Coliform Bacteria in A Central California Coastal Stream

1. Figure 5.Coliform counts relative to rainfall. The highest coliform counts were found at sites 2, 4, and 5 Figure 1.Frenchman’s Creek. The water runs from coastal scrub through agricultural and suburban developments to the Pacific Ocean. This is the site where the MPN for both fecal coliforms and enterococci is at its highest. Figure 4.Sites of fecal contamination from mammals. Figure 3. Coliform counts along Frenchman’s Creek. The sites shown in red had fecal coliforms present. Figure 2. Collection sites along Frenchman’s Creek. USGS 7.5-minute quadrangles Montara Mountain and Half Moon Bay. Distribution Of Fecal Coliform Bacteria in A Central California Coastal Stream Tim Viray, Eric Fung, and Christine Case Biology Department, Skyline College, San Bruno CA • Results • Fecal contamination was found in sites 3, 4, and 5 (Figures 3 and 4), which indicates that the source of contamination is nearer the estuary than the headwaters. • No coliforms were found in plant and soil samples collected at sites 3, 4, and 5. • Enteroccocus bacteria are present and abundant in the sites where fecal contamination was found (Figure 4). • Higher coliforms counts were found during periods of rainfall suggesting stormwater runoff as the source of contamination (Figure 5). Abstract Pillar Point is a popular recreation area and one of the most contaminated beaches along the central California coast. This study was undertaken to locate the source of fecal contamination at Pillar Point. Identifying the source of fecal contamination in coastal creeks is important for protecting the health of swimmers and the coastal ecosystem. Frenchman’s Creek is the only stream that drains the Coast Ranges into the ocean at Pillar Point. The creek flows from coastal sage scrub, through rural and suburban watersheds, to the ocean. We conducted a systematic survey of water, soil, and vegetation along the 4-km creek from headwaters to estuary. Coliform and Enterococcus bacteria were used as indicators of fecal contamination. Total coliform and fecal coliform bacteria were counted using the multiple-tube method. A membrane-filtration test was used to determine enterococcal numbers in the samples. Fecal contamination begins approximately 0.8 km upstream from the estuary; heavy contamination was detected at three of the sites investigated. In these sites, total coliforms exceed 2400/100 mL and enterococci exceed 80/100 mL. Fecal coliforms (from mammals) were found at these sites. Coliform counts are being performed on soil and aquatic vegetation to determine whether these are reservoirs for fecal coliform bacteria or the fecal coliforms are from land-based anthropogenic sources. • Materials & Methods • Water samples were collected along Frenchman’s Creek from headwaters to the estuary between April and July 2011 (Figure 2). • Samples were collected by washing 480 mL plastic bottles and collecting approximately 240 mL of the creek’s water. • Soil and plant samples were also collected around the area where water samples were collected and placed in zip-lock bags. • Coliform counts were performed on water, plant, and soil samples using the multiple-tube method with lauryl-sulfate lactose broth. Methylumbelliferone glucuronide (MUG) agar incubated at 44±0.5°C was used for the confirming test (2). • The membrane filter technique was used on the water sample to determine enteroccoci on Enterococcus Agar and E. coli on Endo Agar (2). • Discussion & Conclusion • During the summer and fall season, local farmers raise the dam between sites 3 and 4 (Figure 2) to provide irrigation water. • • The water level was raised by 15–20 feet, which covered multiple smaller water runoffs that could be possible sources of the contamination. • • We cannot confirm the exact location of the contamination but we have narrowed the source to sites 4 and 5. • • We confirmed that soil or riparian vegetation are not reservoirs for the fecal bacteria, which infers that the contamination is from land-based anthropogenic sources. • • The higher coliform counts found during periods of rainfall suggest that stormwater drainage contributes to contamination of the creek. Aim To determine the source of fecal contamination into Frenchman’s Creek. Future Studies • Locating storm drains or sewage cross-connections along the creek can be done to verify whether these factors contribute to the contamination. • Sampling at the tunnel/storm drain that links to a florist warehouse/green-house. This runoff from the florist could be the source of the contamination. This site is between sample sites 4 and 5. • Background • • Pillar Point is listed as one of the 10 most polluted beaches in San Mateo County (1). • • Illnesses associated with fecal pollution include skin rashes, respiratory infection, meningitis, gastroenteritis, and hepatitis (1). These illnesses are transmitted by water contact sports and from consuming marine animals. • • Transfer of pathogenic bacteria among fishes and other marine organisms can directly affect humans (4). • Fecal contamination at Pillar Point Harbor threatens commercial fishing and recreation (7). • • Frenchman’s Creek (Figure 1) is a major contributor to the fecal distribution of Pillar Point (1). • • Coliforms are aerobic or facultatively anaerobic, gram-negative, non-endospore-forming, rod shaped bacteria that ferment lactose to form gas within 48 hr of being placed in lactose broth at 35-37°C. Fecal coliforms are found in the human intestines. They produce the enzyme -glucuronidase when put on a methylumbelliferyl--D-glucuronide at 44.5°C. Total coliforms include fecal coliforms as well as coliforms that grow at 35-37°C (3). • Escherichia coli and enteroccoci are used as indicator organisms for fecal contamination because they are found in the intestines of warm-blooded animals (5). • • E. coli can survive in waterways in the biofilms that form on some most surfaces (6). • • Enterococci are facultatively anaerobic, gram-positive cocci in Lancefield group D. They can also be found in soil, water, food, and are a significant component of human intestinal microbiota (3). Literature Cited 1. Brennan, S,. August 2010. “Ten most polluted beaches in San Mateo County.” Coastsider. http://coastsider.com (5 June 2011).  2. Clesceri, L. S. and A. E. Greenberg, and A. D. Eaton (eds). Standard methods for the examination of water and wastewater, 20th ed. Washington, D. C.: American Public Health Association, 1999.  3. Holt, J. G. (ed.) Bergey's Manualof Determinative Bacteriology, 9th ed. Baltimore: Williams & Wilkins, 1994.  4. National Research Council (U.S.). From Monsoons to Microbes: Understanding the Ocean’s Role in Human Health. National Academy Press, Washington D.C., 1999.  5. O’Brien, D. 2011. “A Better To Track Salmonella and E. coli in Waterways.” Agricultural Research Magazine 206: 8.  6. Perry, A. 2011. E. coli: Alive and Well, Probably in a Streambed Near You.” Agricultural Research Magazine 211: 20.  7. “Pillar Point Harbor.” 1998-2004. San Mateo County Harbor District. http://www.smharbor.com/pillarpoint/ (29 July 2011). • Acknowledgements • Skyline MESA and SACNAS for supporting our project • Colleagues with whom we worked countless hours during the entire spring and summer semesters   • Pat Carter for providing us with all the materials we need to do our experiment well • Professor Christine Case who inspired us to do our best and pushed us to go beyond ourselves to get better.