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1.
ABSTRACT: As a part of a water quality survey of the Spoon River, Illinois, algal genera were identified and their densities were enumerated. Weekly samples were collected at five stations starting on June 1, 1971. This report presents the first year's results. Algal densities for each station were found to be distributed geometrically normal. Total algal densities increased as water progressed downstream. Although water temperature has been observed to be an important factor affecting the density and the composition of algae in streams, attempts to correlate algal densities with temperatures for the Spoon River were not fruitful. Correlations of algal densities with dissolved oxygen, flow, and coliform densities also could not be made. The dominant genera observed were Cyclotella, Navicula, Scenedesmus, and Euglena. On the average diatoms accounted for 87% of all algae counts. The average diversity indices varied about 1.0 to 1.5 for five stations. There did not appear to be any advantage in the use of diversity index over that of algal density and genera richness in characterizing algae in the Spoon River.  相似文献   

2.
ABSTRACT: The Oregon Water Quality Index (OWQI) is a single number that expresses water quality by integrating measurements of eight water quality variables (temperature, dissolved oxygen, biochemical oxygen demand, pH, ammonia+nitrate nitrogen, total phosphorus, total solids, and fecal coliform). Its purpose is to provide a simple and concise method for expressing the ambient water quality of Oregon's streams for general recreational use, including fishing and swimming. The OWQI, originally developed in the 1970s, has been updated based upon improved understanding about water quality behavior. This report describes the historical basis of the OWQI and defines the improved design of the present OWQI. The index allows users to easily interpret data and relate overall water quality variation to variations in specific categories of impairment. This report demonstrates the value of the OWQI in presenting spatial and temporal water quality information. The OWQI improves comprehension of general water quality issues, communicates water quality status, and illustrates the need for and effectiveness of protective practices.  相似文献   

3.
Lake Holiday, a human-made recreational lake in northern Illinois, was threatened with closure due to high bacterial levels. A factorially designed experiment with multivatiate responses was developed to study and identify the main sources of pollution. Data on total coliform, fecal coliform, fecal streptococci, dissolved oxygen, pH, ammonia-N, total phosphorus, nitrate/nitrite-N were analyzed using regression models describing dam spillway loads as a function of source loads and time. The results suggest that the relationships among source, time, and load are complex, even though only two sources account for most of the lake's loading Stevens Brook, which receives the discharge from the Somonauk Sewage Treatment Plant, and Somonauk Creek, which is the major drainage, contribute high loads of bacteria and nutrients to the lake. The influent loads contributed to the lake are discharged at the dam over about 4 weeks  相似文献   

4.
ABSTRACT: The impact on water quality by agricultural activity in karst terrain is an important consideration for resource management within the Appalachian Region. Karst areas comprise about 18 percent of the Region's land area. An estimated one-third of the Region's farms, cattle, and agricultural market value are on karst terrain. The purpose of this study was to compare fecal bacteria densities in karst groundwater impacted by two primary agricultural land uses in central Appalachia. Fecal bacteria densities were measured in cave streams draining two primary land management areas. The first area was pasture serving a beef cow-calf operation. The second area was a dairy. Neither area had best management practices in place for controlling animal wastes. Median fecal coliform and fecal streptococcus densities were highest in cave streams draining the dairy. Median fecal coliform densities in the dairy-impacted stream were greater than 4,000 CFU/100 ml and the median fecal coliform densities in the pasture-impacted streams were less than 10 CFU/100 ml. Median fecal streptococcus densities in the same streams were greater than 2,000 CFU/100 ml and 32 CFU/100 nil, respectively. A second dairy, with best management practices for control of animal and milkhouse waste, did not appear to be contributing significant amounts of fecal bacteria to the karst aquifer. It was concluded that agriculture was affecting bacterial densities in the karst aquifer. New management practices specifically designed to protect karst groundwater resources may be one way to protect the groundwater resource.  相似文献   

5.
ABSTRACT: The transmission of disease in ground water is a topic of great concern to government agencies, ground water specialists, and the general public. The purpose of this study was to compare the temporal variability in storm flow of fecal coliform bacteria densities and Cryptosporidium parvum oocyst densities in agriculturally impacted karst ground water. Cryptosporidium parvum oocyst densities ranged from 0 to 1,050 oocysts/1, and mean storm densities ranged from 3.5 to 156.8 oocysts/1. Fecal coliform densities ranged from less than 1 CFU/100ml to more than 40,000 CFU/100ml, and geometric mean storm densities ranged from 1.7 CFU/100ml to more than 7,000 CFU/100ml. Fecal coliform densities correlated well with flow during storms, but Cryptosporidium oocyst densities exhibited a great deal of sample to sample variability and were not correlated with flow. Fecal coliform densities did not correlate positively with Cryptosporidium oocyst densities. Fecal coliform densities were greatest at storm peaks, when sediment loads were also greatest. Multiple transport mechanisms for fecal coliform bacteria and C. parvum oocysts may necessitate various agricultural land management and livestock health maintenance practices to control movement of pathogens to karst ground water.  相似文献   

6.
ABSTRACT: Nine surface water‐quality variables were analyzed for trend at 180 Virginia locations over the 1978 to 1995 period. Median values and seasonal Kendall's tau, a trend indicator statistic, were generated for dissolved oxygen saturation (DO), biochemical oxygen demand (BOD), pH (PH), total residue (TR), nonfilterable residue (NFR), nitrate‐nitrite nitrogen (NN), total Kjeldahl nitrogen (TKN), total phosphorus (TP), and fecal coliform (FC) at each location. Each location was assigned to one of four physiographic regions, and mean state and regional medians and taus were calculated. Widespread BOD and NFR improvements were detected and FC improvements occurred in the state's western regions. TR and TKN exhibited predominantly increasing trends at locations throughout the state. BOD, TKN, NFR, and TR medians were higher at coastal locations than in other regions. NN, TKN, and TR exhibited predominantly increasing trends in regions with high median concentrations, while declining trends predominated in regions with relatively high BOD, FC, and NFR medians. Appalachian locations exhibited the greatest regional water‐quality improvements for BOD, FC, NFR, and TKN. Factors responsible for regional differences appear to include geology, land use, and landscape features; these factors vary regionally.  相似文献   

7.
Cumulative impact of marinas on estuarine water quality   总被引:1,自引:0,他引:1  
The purpose of this work is to present a modeling approach for assessing and managing the cumulative impact of marinas on estuarine systems. In doing so, both a water-quality model and a planning and management model are developed. The water-quality model predicts biochemical oxygen demand (BOD) and fecal coliform (FC) loadings from marina sources in a hypothetical North Carolina estuary. By running the water-quality model repeatedly with varied loading input, impact coefficients are determined. These impact coefficients are used in the planning and management model, the output of which gives the sizes and locations of marinas in the estuarine system such that dissolved oxygen (DO) and FC water-quality standards are maintained.Five different estuarine development scenarios are considered. Each scenario is evaluated with respect to both maximum and uniform land development constraints. In addition, two alternative fecal coliform standards are used with each of the development options.  相似文献   

8.
ABSTRACT: Surface water impairment by fecal coliform bacteria is a water quality issue of national scope and importance. In Virginia, more than 400 stream and river segments are on the Commonwealth's 2002 303(d) list because of fecal coliform impairment. Total maximum daily loads (TMDLs) will be developed for most of these listed streams and rivers. Information regarding the major fecal coliform sources that impair surface water quality would enhance the development of effective watershed models and improve TMDLs. Bacterial source tracking (BST) is a recently developed technology for identifying the sources of fecal coliform bacteria and it may be helpful in generating improved TMDLs. Bacterial source tracking was performed, watershed models were developed, and TMDLs were prepared for three streams (Accotink Creek, Christians Creek, and Blacks Run) on Virginia's 303(d) list of impaired waters. Quality assurance of the BST work suggests that these data adequately describe the bacteria sources that are impairing these streams. Initial comparison of simulated bacterial sources with the observed BST data indicated that the fecal coliform sources were represented inaccurately in the initial model simulation. Revised model simulations (based on BST data) appeared to provide a better representation of the sources of fecal coliform bacteria in these three streams. The coupled approach of incorporating BST data into the fecal coliform transport model appears to reduce model uncertainty and should result in an improved TMDL.  相似文献   

9.
Water samples from streams and springs in the Great Smoky Mountains National Park were analyzed for fecal coliform, fecal streptococcus, and total coliform bacteria. Levels of bacteria were found to be highly variable but related to elevation, time of year, type of water source, and water level of the streams. Visitors did not seem to be major contributors to bacterial contamination. Levels of fecal coliform and total coliform in most water samples were unsuitable for drinking without treatment. Tennessee state standards for body contact recreation (swimming and wading) were exceeded in a few samples but none from streams suitable for swimming. As a result of these findings, park managers increased efforts to inform visitors of the need to treat drinking water and removed improvements at backcountry springs which tended to give the springs the image of safe, maintained water sources.  相似文献   

10.
ABSTRACT: Fecal contamination and organic pollution of an agricultural drainage in northeast Indiana was high. Bacterial counts (total coliform, TC; fecal coliform, FC; and fecal streptococcus, FS) and biochemical oxygen demand (BOD) were used to assess waste concentrations. Coliform counts indicated that sections of the drainage receiving septic effluent had waste concentrations far in excess of public health standards (mean FC = 550,000/100 ml). Areas of drainage remote from septic tank pollution were found to occasionally meet federal public health standards for whole body contact recreation but generally these areas had twice the allowable limit of 200 FC/100 ml. Bacterial contamination was highest during runoff events when the median values for TC, FC, and FS were 5, 3, and 17 times greater, respectively, than the median values during low stream discharge. Surface flows carried contaminants from unconfined livestock operations and fecally contaminated sediment was transported by high waters. During one runoff event a BOD loading of 36.7 kg/km2 was recorded and the peak BOD concentration observed was 16 mg/l. A discharge of liquid manure from a confined livestock operation caused a major fish kill. Pollution from septic tanks and unconfined livestock is greatest at high stream discharge when dilution reduces the impact on aquatic life.  相似文献   

11.
ABSTRACT: A study of residential canal system on the Mississippi Gulf Coast and adjacent natural water bodies was conducted to determine the relationship in flushing characteristics between man-made and natural systems. The comparison was based on measurements of temperature, salinity, conductivity, coliform, pH, transparency, biological oxidation demand, dissolved oxygen, bathymetry, tides, water velocity, and Rhodamine dye concentrations. The results indicate that coliform bacteria increase with increasing distance of stations from St. Louis Bay and dissolved oxygen decreases in a similar manner. Biological oxidation demand was low at all stations; showing no differences between natural and man-made systems. The canal system Studied was shallower than adjacent water bodies and water velocities in the canal system are a function of tidal amplitude while velocities in the river are affected by both tides and runoff. The other parameters measured show little or no differences between natural and man-made systems, but reflect overall seasonal changes. Flushing rates between the residential canal systems and an adjacent natural system are equivalent on the basis of decline in dye concentrations measured over a five-day period.  相似文献   

12.
In Massachusetts, the Charles River Watershed Association conducts a regular water quality monitoring and public notification program in the Charles River Basin during the recreational season to inform users of the river's health. This program has relied on laboratory analyses of river samples for fecal coliform bacteria levels, however, results are not available until at least 24 hours after sampling. To avoid the need for laboratory analyses, ordinary least squares (OLS) and logistic regression models were developed to predict fecal coliform bacteria concentrations and the probabilities of exceeding the Massachusetts secondary contact recreation standard for bacteria based on meteorological conditions and streamflow. The OLS models resulted in adjusted R2s ranging from 50 to 60 percent. An uncertainty analysis reveals that of the total variability of fecal coliform bacteria concentrations, 45 percent is explained by the OLS regression model, 15 percent is explained by both measurement and space sampling error, and 40 percent is explained by time sampling error. Higher accuracy in future bacteria forecasting models would likely result from reductions in laboratory measurement errors and improved sampling designs.  相似文献   

13.
ABSTRACT: A residential single family dwelling was retrofitted to recycle graywater for landscape irrigation and toilet flushing. The objective of this study was to determine improvements in graywater quality by evaluating five simple graywater treatment systems that were easily adapted to the household plumbing. The treatment systems consisted of (1) water hyacinths and sand filtration, (2) water hyacinths, copper ion disinfection, and sand filtration, (3) copper ion disinfection and sand filtration, (4) copper/silver ion disinfection and sand filtration, and (5) 20–μm cartridge filtration. Water quality parameters measured were fecal and total coliform indicator bacteria, nitrates, suspended solids, and turbidity. Reductions in bacterial concentration, suspended solids and turbidity were achieved by all systems tested. Treatment reduced nitrate concentrations to an average of 2.6 mg/liter. Reductions in suspended solids, and turbidity were influenced more by the quality of the graywater entering the treatment system than the efficiency of the systems themselves. The water hyacinths and sand filtration system provided the best graywater quality in terms of the concentrations of fecal indicator bacteria. The system providing the best water quality in regard to average suspended solids after treatment was the water hyacinths, copper ion, and sand filtration system, and the best average turbidity was achieved by the copper/silver ion generating unit with sand filtration. All systems were capable of significant reductions in fecal indicator bacteria, suspended solids, and turbidity; however, additional treatment or disinfection would be necessary to further reduce the level of coliform and fecal coliform bacteria to achieve regulatory standards in the State of Arizona.  相似文献   

14.
ABSTRACT: Bacterial densities (total coliform, fecal coliform, and fecal streptococci) and suspended solids in runoff from a feedlot, pasture, and corn field were measured. Densities of fecal coliform were highest from the feedlot but were 1000 to 10,000 times greater than the water quality standard for swimmable waters from all three land uses. Densities of fecal streptococci were highest from the corn field, which suggests that wildlife are the source of bacteria. Fecal coliform/fecal streptococci ratios distinguished cattle from wildlife as the source of bacterial pollution both among land uses and among seasons of the year. Suspended solids concentrations in runoff ranged from 423 to 925 mg/l and were highest from the corn field. A Geographic Information System (GIS), which utilizes a raster or grid-cell format, was developed to include algorithms associated with non-point source pollution. The system accepts digitally mapped information on soil type, topography, and land use. It calculates characteristics such as slope and slope length, and relates these characteristics to soils and land use parameters in order to produce three dimensional maps of runoff potential, sediment pollution potential, and bacterial pollution potential. It offers the advantages of retaining the geographic character of pollution potential information and of conveying in three-dimensional graphical terms the effects of topography, soil type, land use, and land management practices.  相似文献   

15.
Large-scale deposition of animal manure can result in contamination of surface and ground water and in potential transfer of disease-causing enteric bacteria to animals or humans. We measured total coliform bacteria (TC), fecal coliform bacteria (FC), NO3, NH4, total P, and PO4 in ground water flowing from basalt and sand aquifers, in wells into basalt and sand aquifers, in irrigation water, and in river water. Samples were collected monthly for 1 yr. Total coliform and FC numbers were always higher in irrigation water than in ground water, indicating that soil and sediment filtered most of these bacteria before they entered the aquifers. Total coliform and FC numbers in ground water were generally higher in the faster flowing basalt aquifer than in the sand aquifer, indicating that the slower flow and finer grain size may filter more TC and FC bacteria from water. At least one coliform bacterium/100 mL of water was found in ground water from both basalt and sand aquifers, indicating that ground water pumped from these aquifers is not necessarily safe for human consumption according to the American Public Health Association and the USEPA. The NO3 concentrations were usually higher in water flowing from the sand aquifer than in water flowing from the basalt aquifer or in perched water tables in the basalt aquifer. The PO4 concentrations were usually higher in water flowing from the basalt aquifer than in water flowing from the sand aquifer. The main concern is fecal contamination of these aquifers and health consequences that may arise from human consumption.  相似文献   

16.
The microbiological and physico-chemical characteristics of the drinking water supplied by the Central Borehole at the University of Benin, Ugbowo Campus were investigated. The investigation entailed assessment of the pH, turbidity, total suspended solids, total dissolved solids, dissolved oxygen, temperature, salinity, conductivity, nitrate, nitrite, phosphate, sulphate, chloride, N-nitroso compounds, cadmium, chromium, nickel, lead, zinc, manganese, iron, coliform count, BOD5 and COD of the water at the Central Borehole and at ten residential quarters. The assessment indicated that the water was fit for drinking and other domestic applications. Results were also compared with WHO, EU and Nigeria FEPA standards. The results showed that the pH values of the water (5.01–5.86) and total coliform count (1–2/100 ml) expressed as MPN were outside the limits set by the WHO, EU and FEPA. The data also showed that the other water quality parameters assessed were within WHO, EU and FEPA permissible limits. The results of ANOVA showed that significant changes occurred during distribution.  相似文献   

17.
ABSTRACT: The spatial and temporal variability of dissolved oxygen (DO), biochemical oxygen demand (BOD), nitrate concentration and total coliform (TC) were investigated at nine sampling stations distributed along the main rivers of the Piracicaba River Basin, a 12,400 km2 catchment located in São Paulo State, one of the most developed regions of Brazil. Spatially, a downstream impoverishment of water quality conditions was observed, as seen by the decrease of DO, and increase of BOD, nitrate, and TC. These changes were probably caused by accumulating downstream discharge of domestic and industrial sewage. Temporal evaluation of 18 years of data showed that DO decreased with time for the majority of the sampling stations, while BOD, nitrate, and TC increased. A law, approved at the end of 1991, proposed a new water tax for river water extraction for industrial and agricultural use. The amount of this tax is determined according to the water quality of the extracted water. Therefore, the evaluation of the water quality status in this basin is a first step to help resources managers to determine the values for this tax.  相似文献   

18.
This study examines sources of fecal coliform in Segment 2302 of the Rio Grande, located south of the International Falcon Reservoir in southern Texas. The watershed is unique because the contributing drainage areas lie in Texas and Mexico. Additionally, the watershed is mostly rural, with populated communities known as “colonias.” The colonias lack sewered systems and discharge sanitary water directly to the ground surface, thus posing an increased health hazard from coliform bacteria. Monitoring data confirm that Segment 2302 is not safe for contact recreation due to elevated fecal coliform levels. The goal of the study was to simulate the observed exceedences in Segment 2302 and evaluate potential strategies for their elimination. Fecal coliform contributions from ranching and colonia discharges were modeled using the Hydrologic Simulation Program‐Fortran (HSPF). Model results indicated that the regulatory 30‐day geometric mean fecal coliform concentration of 200 colony forming units (cfu) per 100 milliliters is exceeded approximately three times per year for a total of 30 days. Ongoing initiatives to improve wastewater facilities will reduce this to approximately once per year for 14 days. Best management practices will be necessary to reduce cattle access to streams and eliminate all exceedences. The developed model was limited by the relatively sparse flow and fecal coliform data.  相似文献   

19.
ABSTRACT: Fecal‐indicator bacteria were sampled at 14 stream sites in Anchorage, Alaska, USA, as part of a study to determine the effects of urbanization on water quality. Population density in the subbasins sampled ranged from zero to 1,750 persons per square kilometer. Higher concentrations of fecal‐coliform, E. coli, and enterococci bacteria were measured at the most urbanized sites. Although fecal‐indicator bacteria concentrations were higher in summer than in winter, seasonal differences in bacteria concentrations generally were not significant. Areas served by sewer systems had significantly higher fecal‐indicator bacteria concentrations than did areas served by septic systems. The areas served by sewer systems also had storm drains that discharged directly to the streams, whereas storm sewers were not present in the areas served by septic systems. Fecal‐indicator bacteria concentrations were highly variable over a two‐day period of stable streamflow, which may have implications for testing of compliance to water‐quality standards.  相似文献   

20.
ABSTRACT: Data were developed within a three-year period for indicator bacteria and three species of bacterial pathogens following rural storm event hydrographs. The first flush concept was confirmed in all hydrographs. Bacterial density peaking occurred at or before the hydrograph peaks. FC and FS values were higher in more developed areas than the primary rural test site and their numerical ratios followed similar trends. Chlorine demand of storm waters varied between 8 and 16 mg/l and, the ozone requirement was greater than 32 mg/l in the same waters. Aftergrowth of total coliform bacteria occurred following chlorine and ozone doses of 16 mg/l and 32 mg/l respectively. Fecal coliform, fecal streptococci, Salmonella sp., and Pseudomonas sp. all were reduced to near detectable limits by the disinfectants up to 8 days. Staphylococcus sp. demonstrated a propensity to restablish their populations. Multiple regression analysis of the bacterial groups and species in storm waters suggested the fecal streptococci to have been the most useful group in evaluating bacterial storm water quality, with staphylocci have been closely related insofar as their statistical significance was concerned.  相似文献   

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