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Showing 1 to 20 of 23 for “"water quality models"”.
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Parameter optimisation of river water quality models using genetic algorithms
Rivers can provide valuable supply of drinking water for humans, irrigation water to farmlands, water for hydropower and home for many aquatic ecosystems. However, due to population increase and its adverse effects on the rivers, inappropriate farming activities in the river catchments, and other …
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Interfacing hydrodynamic and water quality models with the Eulerian-Lagrangian method
The problem of interfacing hydrodynamic and water quality models is investigated with emphasis on modeling efficiency, accuracy and flexibility. An Eulerian-Lagrangian type of transport model is proposed for interfacing due to its superior simulation efficiency and numerical resolution in …
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Evaluating PC-based water quality models as tools for land use planning
Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1991.
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An Environmental Decision Support System to Facilitate Stakeholder Interaction with Water Quality Models
… In recent times, emphasis has been placed on watershed-based solutions to remediate the problems of diffuse source pollution and to engage stakeholders in designing solutions. Water quality models are an integral part of this process; such models are often inaccessible to lay stakeholders. A …
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Predicting water quality effects on bay anchovy (Anchoa mitchilli) growth and production in Chesapeake Bay: linking water quality and individual-based fish models
Water quality in the Chesapeake Bay and the Patuxent River has decreased since the 1950s due to an increase in nutrient loadings. Increased nutrient loads have caused an increase in the extent and duration of hypoxic conditions. Restoration via large-scale reductions in nutrient loadings is now …
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An examination of stream reaeration coefficients and hydraulic conditions in a pool-and-riffle stream
Oxygen transfer between flowing surface waters and the atmosphere can be mathematically described as a first-order reaction and is known as stream reaeration. The first-order rate coefficient or stream reaeration coefficient is a necessary input parameter to stream water-quality models and is …
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Hydrodynamic and Water Quality Simulation of Fecal Coliforms in the Lower Appomattox River, Virginia
The Virginia Department of Environmental Quality (VADEQ) under the direction of the United States Environmental Protection Agency (USEPA) has listed the lower Appomattox River as impaired because it violates current water quality standards for fecal coliforms. To advance the analytical process by …
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A study of aquatic sedimentation in Chattanooga, Tennessee, using GIS and remote sensing technology integrated with hydrodynamic and watershed models
… The need to quantitatively monitor water bodies and watersheds is key to reduce excessive suspended concentrations. This study aims to integrate remote sensing technology with numerical watershed and hydrodynamic models and apply them on the Tennessee River and the surrounding …
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Aplicação e calibração de um modelo matemático de qualidade de água
… development, the study of pollutants behavior in water bodies, of suggested models and the study of proposed otimizations methods, became a subject of great interest. Most of water quality models now in use are extensions of two fairly simple equations, proposed by Streeter and Phelps (1925), for …
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Hydrologic and water quality modeling with HSPF : utilization of data from a novel field data collection system and historical archives
Catchment-scale hydrology and water quality studies are empowered by current mobile computing, wireless, and Internet technologies to new levels of technical assessment capability. These technical developments motivate an investigation into the modem uses of hydrologic and water quality models. The …
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Algal Succession and Nutrient Dynamics in Elephant Butte Reservoir
A water quality model was created for Elephant Butte Reservoir, New Mexico to understand nutrient dynamics and algal response during a three year period. The model chosen for this study was CE-QUAL-W2 because of its proven ability to represent hydrodynamics and the ability to represent multiple …
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Modeling Dissolved Oxygen in Lake Powell using CE-QUAL-W2
<p>Water quality models in the Colorado River Basin have been developed for the basin, river, and individual reservoirs. They are used to support water quality programs within the basin. The models are periodically reviewed and updated to improve the accuracy of simulations. Improving the …
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An Examination of the Reference Watershed Approach for TMDLs with Benthic Impairments
This research addresses the Reference Watershed Approach (RWA) in the TMDL process for benthic impairments. In the RWA, do different land use sources (DOQQ and NLCD) or use of alternative water quality models (GWLF and SWAT) result in different stressor loadings? Is there a difference in stressor …
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Spatiotemporal Patterns and Drivers of Surface Water Quality and Landscape Change in a Semi-Arid, Southern African Savanna
… In Chapter 2, I evaluate spatial drivers of water quality declines in the Chobe River using spatiotemporal and geostatistical modeling of time series data collected along a transect spanning a mosaic of protected, urban, and developing urban land use. Chapter 3 explores the complex couplings …
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Zooplankton phytoplankton interactions in the San Joaquin River, Ca
… and interactions play a significant role in water quality (e.g., pH and dissolved oxygen [DO]) and the available food supply for higher order organisms in the San Joaquin River Delta. Algae have been shown to significantly impact DO concentrations in the Deep Water Ship Channel (DWSC) of the …
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Simulation of physical and chemical processes in reservoirs: Two case studies.
Managing water quality aspects requires the use of integrative tools that allow a holistic approach to this problem. Water quality models coupled to hydrodynamic models are these tools. This study presents the application of the water quality model WASP coupled to the hydrodynamic model DYNHYD for …
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Tools for managing intermittent water supplies
Nearly one billion people receive water from piped networks that are not always pressurized. These intermittent water supplies (IWS) are more likely to recontaminate the distributed water than continuously-operated (or '24x7') water supplies. In addition, IWS may not provide customers with enough …
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Water quality modelling of eutrophied reservoirs in South Africa
… about the increase in eutrophication-related water quality problems during the early 1970's. The first step taken to control eutrophication was introduction of an effluent phosphate standard that limited the phosphorus concentration in effluents being discharged in certain sensitive catchments …
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A Complex, Linked Watershed-Reservoir Hydrology and Water Quality Model Application for the Occoquan Watershed, Virginia
The Occoquan Watershed is a 1515 square kilometer basin located in northern Virginia and contains two principal waterbodies: the Occoquan Reservoir and Lake Manassas. Both waterbodies are principal drinking water supplies for local residents and experience eutrophication and summer algae growth. …
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REMOTE SENSING OF WATER QUALITY IN LAKE ERIE USING MODIS IMAGERY DATA
<p>The Great Lakes, as the largest fresh surface water system on earth, greatly affects the quality of life and many aspects of the natural environment from weather and climate to wildlife and habitat. Lake Erie was declared as the first Great Lake that demonstrated a lake-wide eutrophic imbalance …
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