We explain a new method of detecting non point source fecal contamination using a PCR based method called Touchdown Polymerase Chain Reaction (TD-PCR). Using genetic markers particular to general, ruminant and human Bacteroides- Prevotella genes, we identified presence in both fresh and salt water environments. Water samples from four sites were collected at approximate 2-week intervals for a year. Samples were analyzed for total coliforms, fecal coliforms, E. coli, and the presence of general, ruminant and human Bacteroides-Prevotella markers. We compared the odds of recovering each PCR marker between sites. We investigated the relationship between rainfall and recovery of PCR markers. Finally, we compared the sensitivity of the PCR methods to standard public health methods. / Graduation date: 2003

With congressional passage of the BEACH Act in October of 2000, Coastal and Great Lakes states were mandated to assess coastal recreation waters for the application of ambient water quality standards. This research encompasses two components involved in applying the BEACH Act statues to Oregon. The first component was to select beach sites in Oregon. The second component involves applying bacterial recreational water standards to select Oregon beaches. Using the guidelines provided by the United States Environmental Protection Agency (EPA), this study develops a method to appraise Oregon marine recreational waters taking into account the following factors: use, available information, pollution threats, sanitary surveys, monitoring data, exposure considerations, economics, and development. In an effort to protect the public from swimming-associated illness attributable to microbial pollution, 24 beaches were identified in Oregon. Of these, 19 beaches were classified as tier 1, or high priority, and five sites were classified as medium priority, or tier 2. Future studies should be directed at ascertaining the beach lengths utilized by Oregon marine recreators since this is an important parameter in targeting bacterial monitoring. Ongoing monitoring of these 24 sites is warranted and new information could be used to update beach tier levels in Oregon. In the second phase of this study, bacterial monitoring data was used for comparison to recreational water quality standards. In October of 2002, the Oregon Department of Environmental Quality (ODEQ) sampled 26 beaches for enterococci and Escherichia coli (E. coli) densities. Of the water sampled from all 26 beach sites, nine exceeded s single sample maximum density of 104 enterococci colony forming units (cfu) per 100 milliLiters (mL). The Oregon beach with the highest exceedance occurred at Otter Rock's South Cove where the enterococci concentration was 4352 most probable number (MPN)/100 mL. A comparison of the 26 sampled beaches to ODEQ's estuarine E. coli standard of 406 organisms/100 mL resulted in two beaches with exceedances. Otter Rock at South Cove had the highest E. coli concentration at 1850 MPN/100 mL. Based on the limited data used in this study, should Oregon adopt the enterococci standard in lieu of the current ODEQ estuarine E. coli standard, more beaches will have exceedances of the recreational water standard. Additional bacterial monitoring is warranted to further characterize the nature and extent of the problem in Oregon. To protect the health of the marine recreating public, future Oregon marine water quality studies should delineate the "no swim" zone around creeks and model the impacts of rainfall on beach sites. / Graduation date: 2004

Few studies, and none in Oregon, have examined the presence and change of water quality parameters over time in popular natural swimming areas. This information is necessary to better understand water quality and risk of illness from either fecal contamination or cross-infection from other swimmers. The purpose of this study was to quantitatively measure bacterial and selected physical and chemical parameters, and collect background information for changes to the current state water quality criteria. Five natural swimming areas in Linn, Benton and Polk counties were chosen and sampled biweekly for physical, chemical, and bacterial parameters over a nine week period from June 28 to August 31, 1996. The results showed differences in bacterial levels over the sampling period which often varied by degrees of magnitude between sites. For example, the range in Escherichia coli levels was between 0 and 1000 colonies/100mL sample for two sites on the same sampling day. Similarly, the range in fecal coliform levels was between 5 and 500 colonies/100mL sample. The daily colony counts at each site exceeded the state standards at least 10% of the time for E. coli and 21% of the time for fecal coliform. At the most popular swimming site, Montieth Park. the fecal coliform regulatory levels were exceeded 79% of the time and E. coli levels were exceeded 42% of the time. This may be due to turbidity, high bather load, or a broken sewer line. The 30 day log mean of these values shows consistently elevated fecal coliform problems only at Montieth Park. For the other sites, the log means did not exceed the state and federal regulatory limits for fecal coliform or E. coll. This raises questions about which estimates should be used to assess public health risk. None of the other parameters in this study were correlated with bacterial counts, so it appears that none of these factors is solely responsible for elevated bacterial levels. Further testing should be done at Montieth Park to determine the cause of the elevated fecal coliform levels. Any follow-up studies should test several different indicator organisms in addition to E. coli for comparison and assessment of their relationship to public health risk. / Graduation date: 1997

Pathogens, such as Escherichia coli and fecal coliforms, are causing the majority of water quality impairments in U.S., making up ~87% of this grouping's violations. Predicting and characterizing source, transport processes, and microbial survival rates is extremely challenging, due to the dynamic nature of each of these components. This research built upon current analytical methods that are used as exploratory tools to predict pathogen indicator counts across regional scales. Using a series of non-parametric methodologies, with spatially explicit predictors, 6657 samples from non-estuarine lotic streams were analyzed to make generalized predictions of regional water quality. 532 frequently sampled sites in the Oregon Coast Range Ecoregion, were parsed down to 93 pathogen sampling sites in effect to control for spatial and temporal biases. This generalized model was able to provide credible results in assessing regional water quality, using spatial techniques, and applying them to infrequently or unmonitored catchments. This model's 56.5% explanation of variation, was comparable to other researchers' regional assessments. This research confirmed linkages to land uses related to anthropogenic activities such as animal operations and agriculture, and general riparian conditions.