Mathematical Water Quality Model Research Articles

Numerical simulation of hydrological and ecological regime of Siberian rivers’ estuaries in the Russian sector of the Arctic

Numerical simulation of hydrological and hydro-chemical regimes is performed using the mathematical model of water quality, developed at Lavrentyev Institute of Hydrodynamics SB RAS. This method is based on the one-dimensional Saint-Venant equations and the transfer equation of heat, oxygen and other impurities. The paper presents examples of numerical simulation.

Study on One Dimensional Mathematical Model for Unsteady Flow Sediment and Water Quality in Channel with a Sluice

Based on existing mathematical model for one-dimensional unsteady flow and non-uniform water-sediment, the inside boundary condition of sluice has been introduced to establish a mathematical model which is suitable for sediment and water quality in nontidal river channel with sluice, in combination with empirical model of local erosion-deposition and one-dimensional mathematical model for water quality. It can be used to simulate motion of water flow, sediment and pollutant under different operational modes of sluice in tidal reaches. In addition, a mathematical model calculation software for water-sediment and water quality has been developed on this basis after sluice has been built, which is also being used to study the influence of different application solution of sluice in Yongding New River on the motion of sediment and pollutant, so as to provide a basis for the selection of sluice operational modes.

Study on One Dimensional Mathematical Model for Unsteady Flow Sediment and Water Quality in Channel with a Sluice

Based on existing mathematical model for one-dimensional unsteady flow and non-uniform water-sediment, the inside boundary condition of sluice has been introduced to establish a mathematical model which is suitable for sediment and water quality in nontidal river channel with sluice, in combination with empirical model of local erosion-deposition and one-dimensional mathematical model for water quality. It can be used to simulate motion of water flow, sediment and pollutant under different operational modes of sluice in tidal reaches. In addition, a mathematical model calculation software for water-sediment and water quality has been developed on this basis after sluice has been built, which is also being used to study the influence of different application solution of sluice in Yongding New River on the motion of sediment and pollutant, so as to provide a basis for the selection of sluice operational modes.

Explicit Water Quality Model Generation and Rapid Multiscenario Simulation

AbstractEmerging applications in water distribution systems place new challenges on water quality modeling tools, including the need for an explicit mathematical representation and simulation of large ensembles of contamination scenarios. We present a computational framework, referred to as Merlion, that creates an explicit mathematical model for water quality in drinking water distribution systems that is appropriate for embedding within other numerical applications (e.g., optimization). This model is efficiently generated for large water distribution systems and represents an all-to-all mapping (inputs include injections at all possible nodes and time steps, and outputs include concentrations at all possible nodes and time steps), which is necessary for many security applications. The Merlion framework is compared to water quality simulations using EPANET on a set of network models ranging in size from 10 to approximately 13,000 nodes. The simulation results show excellent agreement. Furthermore, the ex...

Marine Wastewater Outfalls and Treatment Systems

Wastewater disposal by marine outfalls is proven and effective and is a reliable and cost effective solution with minimal environmental impacts. The design and siting of submarine outfalls is a complex task that relies on many disciplines including oceanography, civil and environmental engineering, marine biology, construction, economics, and public relations. Marine Wastewater Outfalls and Treatment Systems brings these disciplines together and outlines all tasks involved in the planning and design of a wastewater system involving a marine outfall. This book concerns the design of marine wastewater disposal systems: that is an ocean outfall plus treatment plant. All aspects of outfall design and planning are covered, including water quality design criteria, mathematical modelling of water quality and dilution, gathering required oceanographic data, appropriate wastewater treatment for marine discharges, construction materials for marine pipelines, forces on pipelines and outfall design, outfall hydraulics, outfall construction, tunnelled outfalls, operation and maintenance, monitoring, case studies are discussed and methods for gaining public acceptance for the project are presented. Finally, costs for many outfalls around the world are summarized and methods for estimating costs are given. This is the first book to consider all aspects of marine outfall planning and construction. The authors are all extensively involved with outfall schemes and aware of recent developments. The science and technology of all aspects of outfall discharges into coastal waters and estuaries of treated municipal or industrial wastewater has advanced considerably over the past few years. Marine Wastewater Outfalls and Treatment Systems provides an up to date and comprehensive summary of this rapidly developing area. ISBN: 9781843391890 (Print) ISBN: 9781780401669 (eBook)

Regional water quality management for the Karun–Dez River basin, Iran

AbstractTo achieve water quality goals in a river basin, a water quality management model (WQMM) has been developed through the geographic information system (GIS) approach and a mathematical water quality model. The developed model has been applied to the Karun and Dez Rivers, where water quality has decreased due to heavy pollutant loads from Khuzestan province cities and surrounding areas. Pollution sources, land use, geographic features and measured water quality data of the river basin were incorporated into the Arc‐View GIS database. With the database, the management model calculated management type and management cost for each management project in the river basin. Until now, river management policy for polluted rivers in Iran first penalizes pollution sources and then constructs treatment plants for the pollution sources whose wastewater is released untreated and for which the wastewater quality goal of the Iranian Department of Environment is not met. Different management projects with a time programme were proposed and they were compared with the results of the river quality without any management approach. It became clear that the results based on the management approach were much better than those for the unmanaged condition from the viewpoint of the achievement of water quality goals and cost optimization.

Mathematical model for water quality (portable water): a case study

A water quality model for water-use-goal is proposed. The model is tested with a treatment schedule at a water works for portable water. It was observed that at least a 25 per cent savings can be achieved if the model is employed. Mathematics Connection Vol. 4 2004: 27-30

A river water quality management model for optimising regional wastewater treatment using a genetic algorithm

To achieve water quality goals and wastewater treatment cost optimisation in a river basin, a water quality management model has been developed through the integration of a genetic algorithm (GA) and a mathematical water quality model. The developed model has been applied to the Youngsan River, where water quality has decreased due to heavy pollutant loads from Kwangju City and surrounding areas. Pollution source, land use, geographic features and measured water quality data of the river basin were incorporated into the Arc/View geographic information system database. With the database, the management model calculated treatment type and treatment cost for each wastewater treatment plant in the river basin. Until now, wastewater treatment policy for polluted rivers in Korea has been, first of all, to construct secondary treatment plants for untreated areas, and secondarily, to construct advanced treatment plants for the river sections whose water quality is impaired and for which the water quality goal of the Ministry of Environment is not met. Four scenarios that do not use the GA were proposed and they were compared with the results of the management model using the GA. It became clear that the results based on the GA were much better than those for the other four scenarios from the viewpoint of the achievement of water quality goals and cost optimisation.

Calibration of QUAL2E Model for the Sava River (Slovenia)

The use of mathematical models is a good decision making tool in river basin management for selection of wastewater treatment technologies and for estimation of the impact of discharged wastewater on the quality of receiving streams. In rivers mostly polluted with degradable organic matter, the major effect of wastewater discharge results in a substantial decrease of dissolved oxygen. The model QUAL2E developed by the United States Environmental Protection Agency was applied to wastewater impact assessment in the Sava river (Slovenia). We present the procedures for the determination of input data for the QUAL2E model. The sediment oxygen demand rate constant was determined experimentally in situ using an specially designed device; the degradation rate constant was determined in a river laboratory model; hydrological characteristics were evaluated on the basis of empirical coefficients; while the reaeration rate constant was calculated on the basis of an energy dissipation model. The mathematical water quality model QUAL2E was calibrated on the basis of field and laboratory measurements and validated with an independent set of data for critical summer low flow conditions when the dissolved oxygen concentrations are low. A sensitivity analysis of the model was also performed. The validated model was then used to estimate the impact of municipal and industrial wastewater discharges on dissolved oxygen concentrations in the Sava river near Ljubljana. The model was used to simulate various conditions in the river and various degrees of treatment of discharged wastewaters. It is estimated according to the model predictions that at critical summer low flow conditions, wastewater should be treated to reach a BOD under 30 mg l−1 with the goal that Slovenian water quality standards are not violated, meaning a dissolved oxygen concentration above 5 mg l−1.

Case study on water quality modelling of Dianchi Lake, Yunnan province, South West China

The main aim of this work was to construct and validate a mathematical water quality model of the Dianchi lake, so that by altering input total phosphate (TP) loads the projected changes in the lake water TP concentrations could be estimated. Historical information had indicated deteriorating lake water quality with increasing TP concentrations. The model was based on a simple annual mass balance, relying on 3 years (wet, average and dry) data with all TP loads quantified, 7 years of lake water quality, and 36 years of flow data. All lake processes were considered within a single variable, R. Planning TP removal at STWs and within fertilizer plants, coupled with interventions to reduce non-point TP loads from all land run-off by 50%, suggested future lake water TP concentrations could be stabilised at about 0.3 mg TP/l, i.e. the estimated limit for producing algal concentrations that would cause major problems in water treatment plants. The TP load reductions envisaged as realistic would only stabilise the lake water quality by about the year 2008; interventions, unfortunately, could not return the lake to its former pristine condition. The accuracy of the predictions was ± 0.1 mg TP/1, so collection of better data was needed.

Case study on water quality modelling of Dianchi lake, Yunnan province, South West China

The main aim of this work was to construct and validate a mathematical water quality model of the Dianchi lake, so that by altering input total phosphate (TP) loads the projected changes in the lake water TP concentrations could be estimated. Historical information had indicated deteriorating lake water quality with increasing TP concentrations. The model was based on a simple annual mass balance, relying on 3 years (wet, average and dry) data with all TP loads quantified, 7 years of lake water quality, and 36 years of flow data. All lake processes were considered within a single variable, R. Planning TP removal at STWs and within fertilizer plants, coupled with interventions to reduce non-point TP loads from all land run-off by 50%, suggested future lake water TP concentrations could be stabilised at about 0.3 mg TP/1, i.e. the estimated limit for producing algal concentrations that would cause major problems in water treatment plants. The TP load reductions envisaged as realistic would only stabilise the lake water quality by about the year 2008; interventions, unfortunately, could not return the lake to its former pristine condition. The accuracy of the predictions was ± 0.1 mg TP/1, so collection of better data was needed.

Calibration of qual2e model for The Sava river (Slovenia)

The use of mathematical models is a good decision making tool in river basin management for selection of wastewater treatment technologies and for estimation of the impact of discharged wastewater on the quality of receiving streams. In rivers mostly polluted with degradable organic matter, the major effect of wastewater discharge results in a substantial decrease of dissolved oxygen. The model QUAL2E developed by the United States Environmental Protection Agency was applied to wastewater impact assessment in the Sava river (Slovenia). We present the procedures for the determination of input data for the QUAL2E model. The sediment oxygen demand rate constant was determined experimentally in situ using an specially designed device; the degradation rate constant was determined in a river laboratory model; hydrological characteristics were evaluated on the basis of empirical coefficients; while the reaeration rate constant was calculated on the basis of an energy dissipation model. The mathematical water quality model QUAL2E was calibrated on the basis of field and laboratory measurements and validated with an independent set of data for critical summer low flow conditions when the dissolved oxygen concentrations are low. A sensitivity analysis of the model was also performed. The validated model was then used to estimate the impact of municipal and industrial wastewater discharges on dissolved oxygen concentrations in the Sava river near Ljubljana. The model was used to simulate various conditions in the river and various degrees of treatment of discharged wastewaters. It is estimated according to the model predictions that at critical summer low flow conditions, wastewater should be treated to reach a BOD under 30 mg l −1 with the goal that Slovenian water quality standards are not violated, meaning a dissolved oxygen concentration above 5 mg l −1 .

Mathematical Modelling of Water Quality in Estuaries – A Review

Mathematical Modelling of Water Quality in Estuaries – A Review

Assessing Nonpoint Water Quality for Small Streams

The procedures and results of an assessment study of water quality in a small stream impacted only by nonpoint source pollution are presented. Also, considerations for the design of a small stream monitoring survey are discussed. A mathematical model for water quality in small streams was applied to the monitoring data and estimates of the nonpoint source water quality were obtained. An attempt was made to interpret the nonpoint quality in terms of land use.

Two-Dimensional Mathematical Water Quality Model

A large-scale computer model of water quality in Westernport Bay, Australia, is described. Comparison is made between model predictions and field measurements. The model consists of four submodels, i.e., the Topographic Model, Hydrodynamic Model, Pollutant Transport Model, and the Chemical Kinetics and Interaction Model. The following physical variables are provided as output at grid-points throughout the bay-interpolated depths, tide heights, and velocity components. The movement of nonreacting tracer particles is computed. Concentrations of the following chemicals and other materials, averaged over depth, are determined: (l)Dissolved oxygen deficit; (2) organic carbon, (3) BOD; (4) nitrogen as organic matter; (5) nitrate and ammonia; (6) coliforms; (7) conservative pollutants; and (8) suspended solids. Bulk water temperature is computed also. Computational techniques and experiences with the model are described and proposals for future development are examined.

Streamflow routing for water pollution studies

In connection with the development of a time variable mathematical model for water quality, a special flow routing procedure was designed to process moderate and low discharges. The procedure focuses on the discharge—velocity—time results necessary to study the effects of unsteady flow on stream pollution, in contrast with previously available routing methods which primarily estimate water surface elevations for floods. With input consisting of hydrograph data at an upstream station and discharge—velocity relationships for various reaches of the stream, an electronic digital computer processes a largely empirical program to determine hydrographs at any specified station.

Time varying mathematical model for water quality

By means of a mathematical model and an electronic digital computer, the variation of quality with distance and time was simulated for a 50 mile long stream. For a specified station, time profiles were traced in terms of BOD, DO, coliforms and chlorides. Input consisted of the types of data which are typically obtained from records and sanitary field surveys. Results may be used to predict the effectiveness of water pollution control programs and to study the suitability of a stream for fish propagation or other designated purpose.