Showing papers on "Water quality published in 1986"
TL;DR: The physical, chemical, and biological properties of chlorine dioxide as they relate to water treatment are reviewed in this paper, where the generation reactions as well as the reactions likely to occur in treated water are presented.
Abstract: There is increased interest in using chlorine dioxide to treat drinking water for trihalomethane control, taste and odor control, oxidation of iron and manganese, and oxidant-enhanced coagulation -sedimentation. This article reviews the physical, chemical, and biological properties of chlorine dioxide as they relate to water treatment. The generation reactions as well as the reactions likely to occur in treated water are presented. In addition, the biological properties of chlorine dioxide are reviewed and compared with other common disinfectants.
258 citations
TL;DR: The trend in Lake Michigan water quality over 1975-84 appear to reflect reduced nutrient loadings as indicated by gradual declines in spring total phosphorus (TP) and summer epilimnetic chlorophyll a....
Abstract: Trends in Lake Michigan water quality over 1975–84 appear to reflect reduced nutrient loadings as indicated by gradual declines in spring total phosphorus (TP) and summer epilimnetic chlorophyll a ...
184 citations
TL;DR: The interaction between groundwater and surface water and the discharge–recharge relationships in wetlands affect water quality and nutrient budgets as well as vegetative composition.
Abstract: There is a tremendous diversity in wetland types and wetland vegetation in the United States, caused primarily by regional, geologic, topographic, and climatic differences. Wetland hydrology, a primary driving force influencing wetland ecology, development, and persistence, is as yet poorly understood. The interaction between groundwater and surface water and the discharge–recharge relationships in wetlands affect water quality and nutrient budgets as well as vegetative composition. Hydrologic considerations necessary for an improved understanding of wetland ecology include detailed water budgets, water chemistry, water regime, and boundary conditions. Wetland values are often based on perceived wetland functions. These hydrologic functions include (i) flood storage and flood-peak desynchronization, (ii) recharge and discharge, (iii) base flow and estuarine water balance, and (iv) water-quality regulation. Expanded research and basic data collection focussed on wetland hydrology and its relation to wetlan...
164 citations
TL;DR: In this article, a detailed comparison of the estimated recreational benefits associated with water quality improvements using one member of each class is presented. But the results indicate that while the estimates are quite comparable, analyst judgment played a very important role in the development of both methods.
Abstract: Two classes of methods are currently available to estimate consumers' valuations of improvements in environmental resources-direct and indirect. This paper reports the results of a detailed comparison of the estimated recreational benefits associated with water quality improvements using one member of each class. The findings indicate that while the estimates are quite comparable, analyst judgment played a very important role in the development of both methods.
143 citations
138 citations
TL;DR: In this paper, the authors considered rivers, lakes and their basins as a model to investigate global water environmental issues and developed a new method of numerical water quality estimation for organic river pollution.
134 citations
TL;DR: In this article, the effects of land clearing and drainage as well as effect of drainage system design and management upon hydrologic and water quality parameters were determined, and the most dramatic effect of agricultural land development on hydrology is the 2-3 fold increase in peak runoff rates.
Abstract: The effects of land clearing and drainage as well as effect of drainage system design and management upon hydrologic and water quality parameters were determined. The most dramatic effect of agricultural land development on hydrology is the 2–3 fold increase in peak runoff rates. However, there is little effect upon total water efflux. Land clearing for agriculture does significantly increase N and P efflux in drainage water with the magnitude of the increase being dependent upon soil type. Design of the drainage system, particularly with regard to drain spacing and intensity of surface drainage, can have a large influence upon the proportion of outflow that occurs via surface runoff which is fast and that which leaves the field more slowly via subsurface flow. Improvement of subsurface drainage can result in a 10‐fold increase in the NO3‐N efflux from some soils. However, the increase in NO3‐N efflux with improved drainage can be partially offset by utilizing controlled drainage which reduces NO3‐N efflu...
133 citations
Journal Article•
TL;DR: A number of water quality indices and classifications have been developed and evaluated and the management flexibility provided by their application has been examined in this article, where the authors provide an evaluation of existing practices in use within the water industry for surface water quality classification and assesses water quality index as an alternative method for monitoring trends in water quality.
121 citations
TL;DR: In this paper, the authors examined water quality trends in portions of the Colorado, Humboldt, Snake, Walker, and Carson River Basins, Nevada, through application of an existing water quality index to historical data from control point and adjacent monitoring stations.
Abstract: The assessment of periodic changes in water quality and uniform control standards application has been difficult to attain. A potential solution to this problem is the utilization of water quality indices for preliminary screening of data and identification of geographic areas, chronological periods, and possible source and cause of water quality changes. The purpose of this investigation was to demonstrate a practical use and application of a water quality index in Nevada as an existing option for those who must assess water quality changes on a continual basis. The study examined water quality trends in portions of the Colorado, Humboldt, Snake, Walker, and Carson River Basins, Nevada, through application of an existing water quality index to historical data from control point and adjacent monitoring stations. Index ratings were responsive in characterizing changes in water quality status relative to seasonal trends and geographic location. Identification of average annual and single value control criteria violation in terms of which parameter and degree of violation was facilitated through index application. Frequency and magnitude of impact on overall water quality status was also identified. Future use of indices in this manner should prove a valuable tool in meeting legislative water quality management strategies.
112 citations
TL;DR: The Norfolk Broadland has suffered extreme eutrophication and Restoration of the once clear water and aquatic plant communities from the present phytoplankton dominance is sought.
Abstract: SUMMARY (1) The Norfolk Broadland has suffered extreme eutrophication. Restoration of the once clear water and aquatic plant communities from the present phytoplankton dominance is sought. (2) In the first two experiments, Alderfen Broad was isolated, by diversion of an inflow stream, without removal of its recently-deposited phosphorus-rich sediments. In the second, sediment was removed from Cockshoot Broad and dams were placed against the effluent-rich River Bure, but the Broad continued to be fed by a small stream draining an agricultural and fen catchment. (3) In four years (1979-82) after isolation of Alderfen Broad, the phytoplankton crop was greatly reduced and the water became clear. Net release of P04-P from the sediment ceased and the Broad became dominated by Ceratophyllum demersum L. Then, because of the reduction in turbulence of the water column by the plants, and the organic matter supplied to the sediment surface in their decay, the mechanism for release of P04-P from the sediment was reactivated and, in 1984, supported a large phytoplankton crop in the spring. The aquatic plant population declined. In 1985 there was both spring and summer phytoplankton growth, the latter probably supported by nitrogen-fixation, and the aquatic plant growth was negligible. (4) In Cockshoot Broad a reduction in phytoplankton growth followed soon after isolation and sediment-removal, and the water became very clear and has remained so. Part of the Broad has already recolonized with a diverse collection of aquatic plants. (5) The consequences of these results for the management of the rest of the Broadland waterway are discussed.
01 Jan 1986
TL;DR: It is widely recognised that surface waters in urbanised areas are water quality limited and that secondary treatment of dry weather flows is insufficient to improve receiving water quality or to achieve and maintain long term quality objectives.
Abstract: It is widely recognised that surface waters in urbanised areas are water quality limited and that secondary treatment of dry weather flows is insufficient to improve receiving water quality or to achieve and maintain long term quality objectives. The impact of urban runoff is perceived by many at the local municipal or borough level as limiting and impairing the full and beneficial uses of receiving waters in urban environments. Existing sewer design, operation and management singularly fails to embrace or adequately incorporate the quality dimension and the water industry in both Europe and America has been slow to undertake post-project appraisal in terms of evaluations of storm sewer performance. This is despite the accepted fact that, for example, some 35% of the total annual pollutant levels discharged to receiving waters in the U.K. comes from combined or storm sewer overflows which only operate some 2–3% of the time. It is also a fact that total effluent discharges represent a very significant proportion of most urban river flows (1). A recent US Environmental Protection Agency report (2) stated that urban nonpoint source water quality problems affect some 20% of the nation’s river mileage whilst Heaney and Huber (3) have indicated that 36% of 248 urbanised areas in the US suffer priority runoff problems.
TL;DR: In the Lake States, clearcutting natural peatlands will not change annual streamflow nor will it seriously impact water quality if logging is done on frozen soils as mentioned in this paper, but clearcutting will cause water tables to fluctuate more, ranging from 9 cm higher to 19 cm lower.
Abstract: The impact of forests on water has been a subject of argument for more than a century. It still is; and many studies conform that there is no single right answer in the debate. In the Lake States, clearcutting natural peatlands will not change annual streamflow nor will it seriously impact water quality if logging is done on frozen soils. However, clearcutting will cause water tables to fluctuate more, ranging from 9 cm higher to 19 cm lower than in peatlands with mature forests. Clearcutting upland hardwoods or conifers will increase annual streamflow by 9 to 20 cm (a 30- to 80-percent increase). Streamflow returns to preharvest levels in 12 to 15 years. Annual peak flows are at least doubled and snowmelt flood-peak increases may persist for 15 years. Water quality is not widely impacted, but operating logging equipment in stream channels will cause channel clogging by filamentous algae and loss of fish habitat. Permanent changes from forest to agricultural and urban land use on two- thirds or more of a watershed will significantly increase the size of flood peaks in the 2- to 30-year return interval storm or snowmelt.
TL;DR: In this paper, the application of ClO 2 a l'eau brute peut reduire de facon importante la formation des trihalomethanes, i.e.,
Abstract: L'application de ClO 2 a l'eau brute peut reduire de facon importante la formation des trihalomethanes
01 Jan 1986
TL;DR: In this article, the authors present a statistical methodology for the assessment of water quality effects of storm water discharges in urban watersheds using simulated data collected by field studies of urban runoff quality.
Abstract: I Pollutional Aspects of Urban Runoff.- Pollutional Aspects of Urban Runoff.- Toxic Contaminants in Urban Runoff: A Case Study.- Solids, Nutrients and Chlorides in Urban Runoff.- Discussion.- II Field Studies of Urban Runoff Quality.- Field Studies of Urban Runoff Quality.- Use of Field Data in Urban Drainage Planning.- Design of Data Collection Systems.- Data Evaluation in Field Studies of Urban Runoff Quality: Aspects of Assessing the Measurement Interval.- Discussion.- III Deterministic Modeling of Runoff Processes.- Deterministic Modeling of Urban Runoff Quality.- Continuous Mass-Balance of Pollutant Build-Up Processes.- Discussion.- IV Statistically-Based Modeling of Urban Runoff Processes.- Statistically Based Modelling of Urban Runoff Quality: State of the Art.- A Statistical Methodology for the Assessment of Water Quality Effects of Storm Water Discharges.- TSS, BOD5 and COD Accumulation and Transport Over Urban Catchment Surfaces: A Modelling Approach.- Discussion.- V Conventional Pollutant Impacts on Receiving Waters.- Conventional Pollutant Impacts on Receiving Waters.- Measured CSO Contribution to River Quality Deterioration and Methodologic Approach for Negative Influence Evaluation.- Discussion.- VI Toxic Pollutant Impacts on Receiving Waters.- Toxic Pollutants: Impact and Fate in Receiving Waters.- Aquatic Fate and Transport Modeling Techniques for Predicting Environmental Exposure to Organic Pesticides and Other Toxicants - A Comparative Study.- Discussion.- VII Receiving Water Modeling.- State-of-the-Art, Physically-Based and Statistically-Based Water Quality Modeling.- Eutrophication Modelling of Small Urban Lakes.- Realistic Water Quality Modeling.- Continuous Simulation Models to Evaluate Urban Drainage Impacts in Ontario.- Discussion.- VIII Runoff Quality Management.- Urban Stormwater Runoff Quality Management: Low-Structurally Intensive Measures and Treatment.- Structural Measures for Runoff Quality Management.- The Swirl Concentrator as an Urban Runoff Treatment Device.- A Conceptual Model Optimizing the Maintenance of Grit Chambers in Combined Sewers.- Standardization of Detention Pond Design for Phosphorous Removal.- Discussion.- IX Real-Time Control.- Urban Runoff Quality Management by Real-Time Control.- Performance of Hardware Components for Real Time Management of Sewer Systems.- Operational Algorithms for Application in Real-Time Control of Combined Sewer Systems.- Discussion.- X Future Research Needs.- Future Research Needs.- List of Participants.- Author Index.
TL;DR: In this article, data from water quality studies conducted in the Sudbury, Ontario, Canada area indicate that substantial decreases in the acidity of surface waters have accompanied reductions in SO2 emissions from the smelting industry since 1977.
Abstract: Data from water quality studies conducted in the Sudbury, Ontario, Canada area indicate that substantial decreases in the acidity of surface waters have accompanied reductions in SO2 emissions from the Sudbury smelting industry since 1977. On average, acidic lakes in the Sudbury area showed a decrease in H+ of ∼ 50% between 1974–76 and 1981–83, and the severity of springtime pH depressions in streams decreased. Although many Sudbury area surface waters remain highly acidic, general decreases in acidity appear to be continuing. The results demonstrate that reductions in emissions of acids and acid precursors result in concomitant improvements in water quality.
TL;DR: The Vollenweider-OECD eutrophication model has been expanded to approximately 400 lakes and it is possible to make a quantitative prediction of the effects of a detergent phosphate ban and thereby to ascertain the potential benefits of such a ban.
Abstract: The Vollenweider-OECD eutrophication model has been expanded to approximately 400 lakes It is possible to make a quantitative prediction of the effects of a detergent phosphate ban and thereby to ascertain the potential benefits of such a ban In order to assess the effect of a detergent phosphate ban on water quality it is necessary to know the percentage of phosphorus in the domestic waste water that enters the water body, either directly or indirectly, and the percentage of the total phosphorus load that is derived from domestic wastewater Although detergent phosphate bans generally will not result in an overall improvement to water quality, there may be some situations in which eutrophication-related water quality would be improved by a ban 8 references, 1 figure, 1 table
Book•
01 Jan 1986
TL;DR: In this article, the basic concepts of Hydraulics Hydrology Water Quality Water Pollution Drinking Water Purification Water Distribution Systems Sanitary Sewer Systems Stormwater Control Wastewater Treatment and Disposal Solid and Hazardous Waste Air and Noise Pollution Appendixes Index.
Abstract: Basic Concepts Hydraulics Hydrology Water Quality Water Pollution Drinking Water Purification Water Distribution Systems Sanitary Sewer Systems Stormwater Control Wastewater Treatment and Disposal Solid and Hazardous Waste Air and Noise Pollution Appendixes Index.
TL;DR: Saturated hydraulic conductivity and degree of clay dispersion were determined for a sandy loam and a clay loam soil with waters of different combinations of sodium adsorption ratios SAR (5, 15, 30 and 45 mmol 1/2l−1/2) and total electrolyte concentration TEC (15, 30, 60 and 90 me l−1) followed by distilled water to simulate rainwater.
Abstract: Saturated hydraulic conductivity HC, and degree of clay dispersion DD, were determined for a sandy loam and a clay loam soil with waters of different combinations of sodium adsorption ratios SAR (5, 15, 30 and 45 mmol1/2l−1/2) and total electrolyte concentration TEC (15, 30, 60 and 90 me l−1) followed by distilled water to simulate rainwater Increase in SAR and decrease in TEC of leaching water increased DD and decreased HC of soils The HC values were more highly correlated with SAR than TEC The critical ratio of TEC/SAR of water below which the relative HC is less than the ‘hreshold’ value (ie ≦ 075) was 382 and 201 for clay loam and sandy loam, respectively taking the HC of initial soil with good quality water (SAR = 05, EC = 03dS m−1) as the reference Drastic reductions in conductivity were observed even at SAR = 5 (60–83%) when saline water was displaced by rainwater, sensitivity being greater for the sandy loam than for the clay loam; recovery was negligible when the saline water was again applied Data of EC and clay content of the effluent on application of distilled water suggested that clay dispersion, its movement and lodgement into conducting pores, may be the major cause of HC reduction in sandy loam, whereas in clay loam, surface sealing is the major cause With distilled water application HC values were governed by SAR rather than TEC of initial water used The study thus suggests that existing water quality criterion may underestimate the real soil permeability hazards from saline-sodic waters during rainfall infiltration in monsoon season
01 Oct 1986
TL;DR: In this article, the coterminous United States and Alaska were divided into seven geographic regions representing groups of Corps of Engineers Districts, and a review of literature on mass balance studies of nutrients and heavy metals was provided for each region.
Abstract: : The coterminous United States and Alaska were divided into seven geographic regions representing groups of Corps of Engineers Districts. Within each geographic region, the quality and quantity of literature were examined by wetland type and function within wetland type. The specific water quality functions examined included wetlands as sources, sinks, and transformers of nutrients and heavy metals. A review of literature on mass balance studies of nutrients and heavy metals was also provided for each region. Recommendations are provided to address data gaps identified during the literature review. Study results indicated considerable diversity in the quantity and quality of wetlands water quality literature between and within each geographic region of the coterminous United States and Alaska. In general, wetlands water quality has been studied most intensely in the estuarine marshes of the Gulf and North Atlantic coasts. Water quality in freshwater wetlands has not received attention commensurate with the wide distribution of these wetland types. Most previous wetlands water quality research has been fragmented into site-specific or function-specific studies. Very few mass balance studies have been conducted. Two complementary approaches to addressing wetlands water quality research data gaps are recommended.
TL;DR: Habitat factors, species richness and abundance of aquatic macrophytes, had the most influence on fish community structure in both areas.
Abstract: Species composition and richness of fish assemblages in altered and unaltered littoral habitats in Lake St. Clair, Michigan, differed between areas. A percid-cyprinid-cyprinodontid assemblage dominated in the unaltered area, Muscamoot Bay, which has a natural shoreline (with almost no alteration due to dredging or bulkheading), high water quality, and high species richness of aquatic macrophytes. A centrarchid assemblage dominated in the altered area, Belvidere Bay, which has a bulkheaded shoreline, many dredged areas, reduced water quality due to inputs of nutrients from a nearby river, and relatively low species richness of aquatic macrophytes. Habitat factors, species richness and abundance of aquatic macrophytes, had the most influence on fish community structure in both areas. The percid-cyprinid-cyprinodontid assemblage was significantly correlated with six species of macrophytes whereas the centrarchid assemblage was significantly correlated with only four. These patterns suggested that pr...
TL;DR: Barium, cadmium and chromium (VI) toxicity in river water is more or less identical to that in deionised water as discussed by the authors, and the results point out the importance of natural water in regulating heavy metal toxicity.
01 Jan 1986
TL;DR: The seasonal variations in the water quality indices of dissolved oxygen, biological oxygen demand (BOD), turbidity, total solids, nitrates, phosphates, hydrogen-ion concentration (pH), temperature and faecal coliforms of the Warri River at five sampling points were investigated from July 1981 to July 1982.
TL;DR: The concentrations and amounts of soluble and total phosphorus in rainfall, runoff, impoundments, and stream flow from several unfertilized watersheds in the Southern Plains have been monitored for the past decade to assess the effects of varying land uses on water quality as indicated by phosphorus concentration as discussed by the authors.
Abstract: The concentrations and amounts of soluble and total phosphorus in rainfall, runoff, impoundments, and stream flow from several unfertilized watersheds in the Southern Plains have been monitored for the past decade to assess the effects of varying land uses on water quality as indicated by phosphorus concentration. Mean annual soluble and total phosphorus concentrations of 12 and 25 μg L−1 were observed in rainfall, 199 and 710 μg L−1 in runoff from unfertilized grassland, and 165 and 1,875 μg L−1 from unfertilized cropland. Soluble phosphorus from rainfall averaged 41 g ha−1, while that exported in runoff averaged 119 and 82 g ha−1 yr−1 for grassland and cropland watersheds, respectively. The load enrichment of phosphorus in runoff compared to rainfall was related to the water soluble phosphorus content of surface soil for each watershed (r2 = 0.96 to 0.99). Soluble and total phosphorus concentrations in rainfall, runoff, and stream flow were sufficient to stimulate accelerated eutrophication acc...
TL;DR: In this paper, the effect of soil surface cover and antecedent moisture on catchment yield of water and sediment; runoff, soil moisture, and soil erosion were monitored on vertisols at two sites on the eastern Darling Downs, Qld., Australia.