Sources Of Indicator Bacteria Research Articles

Meeting Report: Knowledge and Gaps in Developing Microbial Criteria for Inland Recreational Waters

The U.S. Environmental Protection Agency (EPA) has committed to issuing in 2012 new or revised criteria designed to protect the health of those who use surface waters for recreation. For this purpose, the U.S. EPA has been conducting epidemiologic studies to establish relationships between microbial measures of water quality and adverse health outcomes among swimmers. New methods for testing water quality that would provide same-day results will likely be elements of the new criteria. Although the epidemiologic studies upon which the criteria will be based were conducted at Great Lakes and marine beaches, the new water quality criteria may be extended to inland waters (IWs). Similarities and important differences between coastal waters (CWs) and IWs that should be considered when developing criteria for IWs were the focus of an expert workshop. Here, we summarize the state of knowledge and research needed to base IWs microbial criteria on sound science. Two key differences between CWs and IWs are the sources of indicator bacteria, which may modify the relationship between indicator microbes and health risk, and the relationship between indicators and pathogens, which also may vary within IWs. Monitoring using rapid molecular methods will require the standardization and simplification of analytical methods, as well as greater clarity about their interpretation. Research needs for the short term and longer term are described.

Sources of Indicator Bacteria in the Houston Metropolitan Region, Houston, Texas

Sources of Indicator Bacteria in the Houston Metropolitan Region, Houston, Texas

Planning Level Evaluation of Densities and Sources of Indicator Bacteria in a Mixed Land Use Watershed

The lower Buffalo River, NY, is environmentally impaired and the 38 combined sewer outfalls within this reach historically were believed to be the primary source of bacterial contamination. A planning level evaluation of bacteria contamination was done through sample testing and compilation of existing source data, in part, with the aid of GIS technology. The intent of such evaluation is to provide an overview of the magnitude and sources of the water quality problem without extensive resource commitments, as a first step in developing remediation strategies. Testing for fecal coliform and fecal streptococci was done at 12 sites within the watershed for one year, 1992–93. Indicator bacteria densities at all sites generally were high and the state guideline for primary contact (200 fecal coliform 100 ml−1) was exceeded in 69% of 277 samples. Bacteria densities were greatest during storm events, suggesting runoff as an important source pathway. Mean fecal coliform densities significantly increased downstrea...

Sand, soil, and pigeon droppings: sources of indicator bacteria in the waters of Hanauma Bay, Oahu, Hawaii

To investigate the deteriorating bacteriological water quality of Hanauma Bay, Hawaii, samples of shoreline water, sand, land runoff, and mongoose and pigeon droppings were analysed for fecal coliforms, E. coli and enterococci. The results indicate that the major sources contributing to periodic high levels of bacteria in the waters of the Bay are contaminants of the beach sand, such as pigeon feces.

Sand, soil, and pigeon droppings: Sources of indicator bacteria in the waters of Hanauma bay, Oahu, Hawaii

To investigate the deteriorating bacteriological water quality of Hanauma Bay, Hawaii, samples of shoreline water, sand, land runoff, and mongoose and pigeon droppings were analysed for fecal coliforms, E. coli and enterococci. The results indicate that the major sources contributing to periodic high levels of bacteria in the waters of the Bay are contaminants of the beach sand, such as pigeon feces.

Naturally occurring fecal coliforms and fecal streptococci in Hawaii's freshwater streams

AbstractThe recreational quality of stream water in Hawaii was assessed by carefully analyzing stream, sewage, cesspool, and storm drain samples for concentrations of fecal coliform (FC), fecal streptococcus (FS), and selected physical and chemical parameters. High concentrations of FC, far in excess of the recreational water quality standard of 200 FC/100 mL, could be readily recovered from streams with no obvious sources of pollution and increased dramatically as the stream flowed through urbanized areas. Since sewage and cesspool wastes were characterized by a high (>4) FC: FS ratio, whereas stream water and storm drain samples had a low (<0.7) FC: FS ratio, it was concluded that the source of indicator bacteria in streams was not sewage or cesspool but most likely land runoff. The concentrations of indicator bacteria in treated sewage effluent being discharged into streams were determined to be much lower than the concentrations present in the receiving stream water. Thus, the impact of sewage effluent discharge into the streams of Hawaii cannot be properly evaluated by analyzing stream water samples for FC as mandated by law. Concentrations of orthophosphate, which is low in streams and high in sewage, was determined to be a reliable indicator for the presence of sewage effluent in streams.

The Effect of Cattle Grazing on Indicator Bacteria in Runoff From a Pacific Northwest Watershed

AbstractTotal coliform (TC), fecal coliform (FC), and fecal streptococcal (FS) numbers were monitored for 3 years to determine the effect of grazing on the presence of these organisms in runoff from a cattle‐grazed and a nongrazed watershed in the Pacific Northwest. The watersheds were characterized by winter precipitation and summer grazing. Weighted‐average numbers of TC and FS in runoff did not appear to be appreciably different between the two watersheds during the study.Numbers of TC in runoff from both watersheds routinely exceeded 10,000/100 mL. Prolonged absence of grazing animals did not seem to affect number of TC and FS in runoff from the check watershed. Each spring after a period of warm weather and prolonged absence of animals, there were increases in numbers of TC, FC, and FS in the runoff. There was some correlation between recentness of grazing and numbers of indicator bacteria in runoff. However, more than a year after animals were removed from the nongrazed check watershed FC numbers in runoff still exceeded 200/100 mL in many samples, and not until the following year did they drop to < 10/100 mL.Sampling at several locations within the grazed watershed showed that sources of indicator bacteria were well distributed, and as a result were nonpoint after the initial runoff events. Thus, present FC recommendations developed for point‐sources would not apply adequately to grazed land in the Pacific Northwest. Indicator bacteria as presently analyzed would not provide a basis for developing best management practices.

Some effects of pulp and paper wastewater on microbiological water quality of a river

A study was conducted to detect the source of fecal indicator bacteria and measure the resulting impairment of water quality of the Sturgeon River at Sturgeon Falls, Ontario, Canada. The bacteriological water quality of the river above the dam at Sturgeon Falls was fairly good, while below the dam the water quality was degraded. The principal input of fecal indicator bacteria was traced to the paper mill at Sturgeon Falls. The impairment of water quality was detected all the way to recreational areas near the mouth of the river. The impaired stretch of the river had diminished aesthetic appeal. Other sources of indicator bacteria could be masked by the large numbers of similar bacteria discharged from the paper mill. The principal fecal coliform was Klebsiella pneumoniae. In pulp mill wastes the fecal origin of this bacterium can be disputed, and so its presence in large numbers interfered with the interpretation of fecal coliform results. K. pneumoniae is also an opportunistic pathogen which causes infections in humans. Thermotolerant oxidase positive bacteria which were isolated from the paper mill wastes, register as false positives in the fecal coliform test causing problems in interpretation. Pseudomonas aeruginosa was detected in the pulp mill wastewater, and at a level of 82 PA 100 ml −1 in recreational areas of the river. This was considered to be of some hazard to users of the water. In addition, Escherichia coli was detected in the mill wastewater, at about 200 EC 100 ml −1, and this probably indicated some measure of fecal pollution though likely of animal origin. Finally the nutrient rich wastewater led to an approx. 50-fold increase in density of aerobic heterotrophic bacteria in the river water, as well as the production of a slimy filamentous growth on surfaces, stones and wooden pilings, in the river. The principal organism in this slime was the fungus Leptomitus.