<p>Användandet av obehandlat avloppsvatten inom jordbruket är en växande företeelse i många delar av världen. Speciellt i vattenfattiga områden där avloppsvattnet ses som en värdefull och pålitlig resurs. Det höga näringsinnehållet minskar behovet av konstgödsel och detta ökar böndernas inkomster. Men med användandet av avloppsvattnet följer vissa hälsorisker. Bland annat har man sett en högre förekomst av inälvsmaskar hos bönder som använder orenat avloppsvatten jämfört med de som använder rent vatten. Den här vattenkvalitetstudien har utförts längs floden Musi i Andhra Pradesh, Indien. Musi rinner igenom staden Hyderabad och mycket av stadens avloppsvatten dumpas i floden. Nedströms Hyderabad används detta vatten för bevattning. Längs med floden är dammar byggda, för att avleda vattnet i bevattningskanaler. Reservoirer bildas då flödeshastigheten minskar. Studieområdet sträcker sig från Hyderabad och 28.7 km nedströms. Hypotesen var att reservoirerna fungerar som biodammar och syftet var att kvantifiera dammarnas inverkan på vattenkvaliteten och utvärdera dess lämplighet utifrån ett hälso- och jordbruksperspektiv. Inom studieområdet är reningen med avseende på BOD, Nematoder och E coli 86,9%, 99,9% respektive 99,9%. Trots att reningen är så hög överstiger Nematod- och E coli-koncentrationerna Världshälsoorganisationens riktlinjer och utgör en hälsorisk för bönder och konsumenter. Syre- och salthalt ökar nedströms och den höga salthalten kan ha negativ inverkan på jordbrukets avkastning. Genom att titta på reningsmönster och förändring av olika vattenkvalitetsparametrar är en av slutsatserna av detta arbete att reningen i dammarna motsvarar den rening som sker i de anaeroba bassängerna i ett biodammsystem.</p> / <p>The use of untreated domestic sewage in agriculture is a growing practice in many parts of the world. It is being looked upon as a valuable and reliable resource in water scarce communities. Wastewater is usually rich in nutrients and the use results in high yields without the need for artificial fertilisers. But with the use of untreated wastewater follows a number of associated health risks, e.g. a higher prevalence of helminth infections has been seen among wastewater users compared to non-users. This water quality study was performed along the River Musi in Andhra Pradesh, India. The Musi River flows through the city of Hyderabad carrying the most of the town’s wastewater. Downstream of Hyderabad the wastewater is used by farmers for irrigation. Along the river weirs are constructed which diverts the irrigation water into canals and reservoirs are formed where the flow velocity slows down. The study area stretches from Hyderabad and 28.7 km downstream. The hypothesis was that the existing irrigation infrastructure acts like Wastewater Stabilisation Ponds and the aim was to quantify the impact of the weirs on water quality and to evaluate the irrigation water quality in reference to associated health risks and agricultural suitability. Within the study area the BOD, E coli and Nematode removals were 86.9%, 99.9% and 99.9% respectively. Despite the high removal the E coli and Nematodes, the concentrations exceed WHO guidelines for unrestricted and restricted irrigation, and there exists an excess risk of intestinal nematode- and enteric infections for farmers. Dissolved oxygen and salinity increases downstream and due to the high salinity farmers could experience reduced crop yields. By looking at removal patterns, and the change in water quality parameters, the conclusion can be made that the reservoirs act like anaerobic ponds in a Wastewater Stabilisation Pond system.</p>

<p>The aim of this paper is to explain and compare non-compliance of two EU-directives, “the quality of bathing water” and “the working time directive”. This study answers the questions: Why didn’t Sweden implement the directive on bathing water quality and the working time directive correctly? Are the reasons for non-compliance the same or different in the two cases? The paper is designed as a case study and with an explanatory attempt we explain why the two directives weren’t implemented correctly in Sweden. The theoretical approach is based on both general- and EU-specific implementation theories. The reason why the directive on quality of bathing water wasn’t implemented correctly was firstly because of the differences between the Swedish political contents and the EU-directive’s, secondly the vague formulation that caused problems with understanding how to implement the directive. Third and lastly the implementation suffered from the lack of administrative resources. The working time directive had problems with the political contents and the resistance from the trade union and government, which caused delays with the implementation of the directive. By studying these two cases this paper concludes that there is only one point of similarity between the cases, i.e. the political contents.</p>

2 pp. / The greatest management concern with animal wastes is the movement of nitrate into water supplies. Health problems in humans and livestock can result from excessive levels of nitrate in drinking water. This publication outlines the guidelines to minimizing the risk of contaminating your drinking water. It also lists a number of questions to check if your management practices in the collection and storage of animal wastes may pose a risk to your groundwater.

4 pp. / Following on the U.S. Environmental Protection Agency's "Arsenic Rule" decision to require public water systems to lower the allowable arsenic content in drinking water from 50 parts per billion (ppb) to 10 ppb by January 23, 2006, private well owners across the state have realized the importance of testing their own water supply for arsenic. Under Arizona law, it is the sole responsibility of the private well owner to determine the quality (potability) of their private well water. This article discusses the geologic prevelance of arsenic across the state, and options available to the well owner to address this water quality concern. Expected to be the first in a 3-part series on ground water quality issues common in Arizona.

2 pp. / Originally published: 2001 / An onsite sewage treatment system or "septic system" is effective way to safely recycle household wastewater back into the natural environment. The key to effective treatment is proper design, system installation, responsible operation, and periodic maintenance. This article provides information about how to improve septic system performance by taking simple steps at home.

6 pp. / Well Owners' Guide to Ground Water Resources in Yavapai County. AZ1451 / Private well owners are responsible for the safety and quality of their water supply. The nearly 6,000 exempt wells in Gila County are not regulated by any state or federal agency, and lot splits and subdivisions may result in an unregulated water supply serving several homes. This publication is one in a series of county-based publications that identifies well maintenance and testing procedures for the well owner, with an emphasis on water quality concerns for Gila County.

The concept of hydrochemical facies is used to study the distribution and, indirectly, to identify the origin of the chemical character of ground water in the basin-fill aquifer of the Tucson Basin in relationship to the hydrogeologic framework. Hydrochemical fades of ground water is defined operationally in terms of the lateral (horizontal) variation of chemical quality. The following chemical constituents are included in this study: total dissolved solids, calcium, magnesium, sodium, potassium, chloride, sulfate, bicarbonate, pH, nitrate, fluoride, strontium and zinc. A conceptual process-response model relates the regional distribution of dissolved constituents to the following hydrogeologic controls: (a) the chemical composition of the rock and soil in the drainage area before recharge to the ground-water basin and conditions at the recharge sites, (b) the lithology of the basin-fill aquifer, and (c) the direction of groundwater flow within the aquifer itself. Trend surface analysis suggests that the regional distribution patterns of total dissolved solids, calcium, sodium, sulfate and strontium show a tendency to parallel the direction of ground-water flow. The distribution pattern of chloride ions based on old analyses shows a trend opposite to the distribution pattern of chloride ions based on new analyses from the same area. Nitrate content of ground water and specific capacity of wells seem to be related. Q-factor analysis of data from the basin-fill aquifer demonstrates that the overall chemical character of the ground water does not change substantially as it moves through the basin. It is concluded that the chemical character of ground water in the basin-fill aquifer of the Tucson Basin was acquired mainly during contact with various rock types in the drainage basin before recharge. The lithology of the aquifer, presumably, only plays a secondary role in determining the overall chemical composition of the ground water. After recharge to the basin-fill aquifer the distribution of dissolved constituents is controlled primarily by the flow pattern. A chemical equilibrium model of calcite and water is used to approach the problem of determining whether precipitation or dissolution of calcite takes place in the aquifer. Measured calcium ion concentrations and pH values are compared to calcium ion concentrations and pH values computed for the equilibrium model. Assuming that the equilibrium model represents actual conditions in the aquifer, departures from the equilibrium model may be used to predict the chemical behaviour of calcite In the basin-fill aquifer.

Water quality analyses in Grand Canyon examined Colorado River and tributary baseline water quality status in relation to recreational float trip use of the river corridor. Float trip use of Grand Canyon has increased over recent years (since 1966) to levels which have caused concern for water quality-river running associations. River runners have traditionally used the Colorado River and tributaries as sources of drinking and cooking water, for swimming and bathing, and, at times, as a disposal for some refuse, e.g., dishwater and leftover food. Associated with float trip use of the river corridor water resources has been potential water quality hazards. During the 1972 and 1979 float trip seasons (May through September) outbreaks of gastroenteritis occurred among river runners in Grand Canyon, prompting investigation by the Center for Disease Control, Atlanta, Georgia; an enteric pathogen Shigella sonnei was isolated from some river-trip participants. Potentially, the Colorado River or a tributary served as a source or carrier of the pathogen, though this has not been confirmed. Enteric disease organisms excreted in feces by humans, wildlife or domestic animals can become potential sources of infection; water contaminated with fecal organisms can distribute diseases. Water quality analyses of the Colorado River corridor occurred during the 1978 and 1979 river running seasons. Examination of the extensive river corridor necessitated analyses in the field. Travel through the Grand Canyon was via research rafts in a series of six float trips, April through September, in 1978, and two float trips, July and August, in 1979; 82 field days in 1978 and 22 field days in 1979. A total of 497 water quality samples were collected over two seasons from the Colorado River along the 225-mile stretch from Lees Ferry to Diamond Creek, the launch and take-out points of the research trips. The confluent reaches (within approximately 200 yards of the Colorado River) of 26 side creeks in the river corridor were also sampled in 1978; nine tributaries were sampled in 1979. Additional samples collected from upstream locations on some side creeks increased the tributary sample site total to 33 in 1978 and to 13 in 1979 for a two season total of 165 individual tributary samples. Selected microbial, physical, and chemical parameters were measured to determine baseline water quality status in the Colorado River corridor of Grand Canyon. Research emphasis was on microbial water quality; physical and chemical parameters were measured to facilitate evaluation of the microbial profiles. Microbial parameters included fecal coliform bacteria and fecal streptococcus bacteria densities; physical parameters included turbidity and water and air temperature; chemical determinations included alkalinity, hardness, phosphate, nitrate, chloride, total dissolved solids, and pH. Data from 1978 and 1979 show that the Colorado River and tributaries have similar bacterial water quality profiles. Surface waters show predominantly low FC densities, indicating high quality waters for recreational activities, based on established federal and state water quality standards. Treatment of river and tributary surface water is necessary to assure drinking water quality standards. Bottom sediment analyses modify considerably the water quality status represented by surface water analyses alone. Significant densities of enteric organisms are present in the river and tributary environments, representing an important water quality hazard. Associated with resuspension of bottom sediments is the probability of surface water contamination by enteric organisms. Recreational activities, particularly water play in confined tributary pools, can bring river runners in direct contact with concentrated sediment suspension in surface waters.

Aquatic sediments, at a lake beach site in the Tonto National Forest, Arizona, were experimentally disrutped to quantitatively determine the impact of sediment resuspension on recreational water quality. Sediment resuspension was found to significantly degrade the quality of recreational waters. Mean sediment fecal coliform densities exceeded mean fecal coliform densities in overlying waters by 24.7 fold. When these sediments were experimentally disrupted, fecal coliform densities and turbidity levels in the water column increased by 1.4 to 2.8 and 1.1 to 5.4 fold, respectively. The impact of sediment resuspension on overlying waters was short-lived at the point of disruption. Increasing FC densities and turbidities generally peaked within 5 sec of resuspension and declined to preresuspension levels within 500 sec. The magnitude of the resuspension impact was most significantly influenced by water depth. The greatest risk to public health was found to be within the 0.3 m depth zone; that near-shoreline area most intensively used by young children for water play.

The characteristics of dissolved aquatic organic matter present in four natural water sources, as well as corresponding treated waters derived from eight water treatment plants, is described. An assessment is made of the performance of direct filtration, conventional treatment, and lime softening in removing trihalomethane (THM) precursors from a diverse array of water sources. A comparison is made between conventional treatment and direct filtration in removing THM precursors from a common natural water source, the Colorado River. In addition, the effect of selected initial conditions and operating parameters on the direct filtration process are evaluated by using a synthetic water/bench-scale apparatus. Important characteristics of the organic matter, including molecular weight (MW) distribution, carboxylic acidity and humic substances content, appear to affect the removal of this organic material. As a general rule, THM reactivity or yield (ug THM/mg C) increases with MW. The <10,000 MW range was found to be the most consistent reactive fraction of aquatic organic matter. All of the various treatments preferentially removed the most reactive fraction of precursor present in each MW range. None of the various treatments proved to be very effective in removing precursor material below a MW of <500. Humic molecules, with the highest carboxylic acidity and hence highest charge density, are generally more difficult to remove by alum coagulation. All of the various treatment processes studied preferentially removed hydrophobic over hydrophilic aquatic organic matter. None of the source related conditions (fulvic acid, kaolinite, pH) nor process-related conditions (flocculation velocity gradient, mixing time, prechlorination, preozonation) evaluated under the same experimental conditions exerted a major impact upon the performance of the bench-scale direct filtration process. Larger sized particles may be easier to remove by bench-scale treatment, but removal of the smaller particles may result in better removals of organic matter as quantified by NVTOC and UV Absorbance.