Integrated Water Quality Management Research Articles

Model of Sustainable Belawan Harbor Waters Pollution Management Scheme

This study aims to analyze the impact of industrial activities on water quality in Belawan Port, Medan City. The methods used included field surveys, water sampling, and in-depth interviews with stakeholders and communities around the harbor. The results showed that industrial activities at the port significantly affected water quality parameters such as acidity, heavy metal concentration, and the number of pathogenic microorganisms. In addition, the socio-economic conditions of the community around Belawan Port also affect awareness of the environment and the cleanliness of the waters. This study concludes that water pollution management in Belawan Harbor requires an integrated approach between the government, port management, industry, and local communities. Collaborative efforts are needed to implement more effective and sustainable policies to maintain environmental sustainability in this port area. Key recommendations include the establishment of an Integrated Water Quality Management Team and increased active participation from all stakeholders in keeping the waters and environment around Belawan Port clean.

How much do bacterial growth properties and biodegradable dissolved organic matter control water quality at low flow?

Abstract. The development of accurate water quality modeling tools is necessary for integrated water quality management of river systems. Even though some water quality models can simulate dissolved oxygen (DO) concentrations accurately during high-flow periods and phytoplankton blooms in rivers, significant discrepancies remain during low-flow periods, when the dilution capacity of the rivers is reduced. We use the C-RIVE biogeochemical model to evaluate the influence of controlling parameters on DO simulations at low flow. Based on a coarse model pre-analysis, three sensitivity analyses (SAs) are carried out using the Sobol method. The parameters studied are related to bacterial community (e.g., bacterial growth rate), organic matter (OM; partitioning and degradation of OM into constituent fractions), and physical factors (e.g., reoxygenation of the river due to navigation and wind). Bacterial growth and mortality rates are found to be by far the two most influential parameters, followed by bacterial growth yield. More refined SA results indicate that the biodegradable fraction of dissolved organic matter (BDOM) and the bacterial growth yield are the most influential parameters under conditions of a high net bacterial growth rate (= growth rate − mortality rate), while bacterial growth yield is independently dominant in low net growth situations. Based on the results of this study, proposals are made for in situ measurement of BDOM under an urban area water quality monitoring network that provides high-frequency data. The results also indicate the need for bacterial community monitoring in order to detect potential bacterial community shifts after transient events such as combined sewer overflows and modifications in internal processes of treatment plants. Furthermore, we discuss the inclusion of BDOM in statistical water quality modeling software for improvement in the estimation of organic matter inflow from boundary conditions.

Integrated Water Quality Management Model for the Rural Transboundary River Basin—A Case Study of the Sutla/Sotla River

The intensive use of soil and water resources results in a disbalance between the environmental and economic objectives of the river basin. The water quality management model supports good water status, especially downstream of dams and reservoirs, as in the case of the Sutla/Sotla river basin. This research aims to develop a new, improved integrated water quality management model of rural transboundary basins to achieve environmental objectives and protection of the Natura 2000 sites. The model uses river basin pressure analysis to assess the effects of climate and hydrological extreme impacts, and a programme of basic and supplementary measures. The impact assessment of BASE MODEL, PAST, and FUTURE scenarios was modelled using the soil and water assessment tool (SWAT) based on land use, climate and hydrological data, climate change, presence or lack of a reservoir, and municipal wastewater and agriculture measures. Eight future climate change scenarios were obtained with optimistic (RCP4.5) and pessimistic (RCP8.5) forecasts for two periods (2020–2050 and 2070–2100), both with and without a reservoir. The model shows that the most significant impacts on the waterbody come from the nutrients and sediment hotspots, also shows the risk of not achieving good water status, and water eutrophication risk. The modelled average annual increase in sediment is from 4 to 25% and in total N from 1 to 8%, while the change in total P is from −5 to 6%. The conducted analysis provides a base for the selection of tailor-made measures from the catalogue of the supplementary measures that will be outlined in future research.

Source contribution analysis of nutrient pollution in a P-rich watershed: Implications for integrated water quality management.

It is still a great challenge to address nutrient pollution issues caused by various point sources and non-point sources on the watershed scale. Source contribution analysis based on watershed modeling can help watershed managers identify major pollution sources, propose effective management plans and make smart decisions. This study demonstrated a technical procedure for addressing watershed-scale water pollution problems in an agriculture-dominated watershed, using the Dengsha River Watershed (DRW) in Dalian, China as an example. The SWAT model was improved by considering the constraints of soil nutrient concentration, i.e., nitrogen (N) and phosphorus (P), when modeling the nutrient uptake by a typical crop, corn. Then the modified SWAT model was used to quantify the contributions of all known pollution sources to the N and P pollution in the DRW. The results showed that crop production and trans-administrative wastewater discharge were the two dominant sources of nutrient pollution. This study further examined the responses of nutrient loss and crop yield to different fertilizer application schemes. The results showed that N fertilizer was the limiting factor for crop yield and that excessive levels of P were stored in the agricultural soils of the DRW. An N fertilizer application rate of approximately 40% of the current rate was suggested to balance water quality and environmental protection with crop production. The long-term impact of legacy P was investigated with a 100-year future simulation that showed the crop growth could maintain for 12 years even after P fertilization ceased. Our study highlights the need to consider source attribution, fertilizer application and legacy P impacts in agriculture-dominated watersheds. The analysis framework used in this study can provide a scientifically sound procedure for formulating adaptive and sustainable nutrient management strategies in other study areas.

Analysis of deoxygenation and reoxygenation rate in the Indonesia River (a case study: Bedadung River East Java)

Bedadung River is the main river in the Jember Regency – East Java. The organic and inorganic waste from human activity increases potential pollution loads in the river. The pollution load impacts on the water quality of the river. The oxygen existence as an indicator of river water quality that was determined based on deoxygenation and reoxygenation rate. It was one of decision making for the government on water quality management in the watershed. This research aims analyzed pollution loads, deoxygenation and reoxygenation rate of Bedadung River in the Patrang - Sumbersari segment. Simple mathematical analysis model oxygen distribution used the Streeter-Phelps method. This method applied dissolved oxygen data (DO) and biological oxygen demand (BOD) as the input data. The results represented that the highest pollution loads at point 7 in value 1198.6 kg/day. Based on the calculation of oxygen distribution with Streeter-Phelps formula, the rate of deoxygenation (rD) < reoxygenation (rR) a sequence were 0.028 mg/day.L and 0.053 mg/day.L. It indicated a good functioning for pollutant degradation. The government and stakeholder had been maintained through an integrated water quality management scheme and pollution control on the Bedadung River.

Seasonal Variation Characteristics of Pollution Risk in a Riverside Source Area Based on Source Apportionment

Riverbank filtration is internationally accepted as a safe new method for extracting drinking water. This paper describes the structure and characteristics of pollution sources in the Hulan water source area of Harbin during wet and dry seasons, based on groundwater pollution sources apportionment technology. Pollution risk of the water source area was also assessed using the pollution sources-pathway-receptor model. Impacts on water quality safety under the collective effects of seasonal changes and human activities were then analyzed. Results showed that groundwater pollution sources have different spatial distribution characteristics based on pollution source apportionment during wet and dry seasons, with four principal influencing factors:①water-rock interaction caused by exploitation of water sources, ② natural geological processes resulting from dissolution of iron manganese minerals, and pollution by ③ nitrogen and ④ organics in response to human activities. Pollution risk assessment showed that water sources were at low risk during both wet and dry seasons. However, the south area of the water source area showed high groundwater pollution risk during the wet season, while other high-risk areas were mainly distributed around the riverbanks and densely populated areas during the dry season. These findings indicate that human activities greatly influence groundwater pollution risk during the dry season; accordingly, this season should be the focus of integrated water quality management and control for the water source area.

Predicting nonpoint stormwater runoff quality from land use.

Evaluating the impact of urban development on natural ecosystem processes has become an increasingly complex task for planners, environmental scientists, and engineers. As the built environment continues to grow, unregulated nonpoint pollutants from increased human activity and large-scale development severely stress urban streams and lakes resulting in their currently impaired or degraded state. In response, integrated water quality management programs have been adopted to address these unregulated nonpoint pollutants by utilizing best management practices (BMPs) that treat runoff as close to the source as possible. Knowing where to install effective BMPs is no trivial task, considering budget constraints and the spatially extensive nature of nonpoint stormwater runoff. Accordingly, this paper presents an initial, straightforward and cost-effective methodology to identify critical nonpoint pollutant source watersheds through correlation of water quality with land use. Through an illustrative application to metropolitan Denver, Colorado, it is shown how this method can be used to aid stormwater professionals to evaluate and specify retrofit locations in need of water quality treatment features reduce, capture and treat stormwater runoff prior to entering receiving waters.

Development of Spatial Similarity-Based Modeling to Support Integrated Lake Water Quality Management: Recreational Lakes in Klang Valley, Malaysia1

Due to recent climate factors which lead to long dry spells and affect normal water distribution from the reservoir, there is a high potential for tapping water from recreational lakes as a resource alternative for high population density states in Malaysia such as Selangor and Kuala Lumpur. The challenges, however, are due to severe data limitations, no formation of a regular water quality monitoring programme and segregated catchment planning. This paper intends to discuss the application of similarity-based modeling as the alternative technique for integrated lake water quality management under the circumstances of severe data limitation issues and a limited programme of continuous lake water quality sampling and monitoring. The developed spatial model applies a similarity-based technique, with a distance of 1km buffer radius set as model database. LakePutrajaya has been chosen as similarity assessment control point due to its comprehensive data availability and long-term monitoring. Findings showed th...

Interactive Reservoir-Watershed Modeling Framework for Integrated Water Quality Management

Eutrophication is a serious water pollution problem in many lakes and reservoirs. One method of understanding the causes of eutrophication and devising strategies to address this phenomenon is watershed modeling. An integrated model is developed in this paper for simulating and evaluating the water quality protection strategies of reservoirs based on controlling the upstream point and non-point sources of pollution and also reservoir operation. To achieve this, Soil and Water Assessment Tool (SWAT) model is used for modeling of the surface runoff and transportation of pollutant load over the watershed area and then, the numerical model CE-Qual-W2 is used for simulating the reservoir water quality. These models are linked to simulate the transmission and distribution of water quality variables in the Seimare watershed-reservoir system, west part of Iran. After calibration of the models, different strategies for reduction of pollution over the watershed are simulated and ranked based on their efficiency in reducing the pollution load entering into the reservoir. Results show that completion and modernization of the sewage network and wastewater treatment plant of Kermanshah city as long as adopting some measures against the direct release of municipal wastewater into the Gharehsou River can reduce the pollution load by 40–50% as the best short term strategy. It is also found that in the long-term period, watershed management and decreasing local animal husbandry activities are the most effective measure for reducing the nutrient load entering Seimare reservoir, and thus need to be considered in the future watershed management policies and programs.

The nitrogen cycle in highly urbanized tropical regions and the effect of river–aquifer interactions: The case of Jakarta and the Ciliwung River

Groundwater is extensively used in Jakarta to compensate for the limited public water supply network. Recent observations show a rise in nitrate (NO3−) levels in the shallow aquifer, thus pointing at a potential risk for public health. The detected levels are still below national and international regulatory limits for drinking water but a strategy is necessary to contain the growing problem. We combine 3years of available data in the Ciliwung River, the major river flowing through Jakarta, with a distributed river–aquifer interaction model to characterise the impact of urbanisation on the N-cycle of both surface and groundwater systems. Results show that the N-cycle in the river–aquifer system is heterogeneous in space, seasonal dependent (i.e. flow regime) and strongly affected by urban pollution. Results suggest also that although the main sources of N related groundwater pollution are leaking septic tanks, the aquifer interaction with the Ciliwung River may locally have a strong effect on the concentrations. In the general context of pollution control in urban areas, this study demonstrates how advanced process-based models can be efficiently used in combination with field measurements to bring new insights into complex contamination problems. These are essential for more effective and integrated management of water quality in river–aquifer systems.

Optimization of integrated water quality management for agricultural efficiency and environmental conservation

The scarcity of water resources in Egypt has necessitated the use of various types of lower quality water. Agricultural drainage water is considered a strategic reserve for meeting increasing freshwater demands. In this study, a novel model series was applied to a drainage basin in the Nile Delta to optimize integrated water quality management for agriculture and the aquatic environment. The proposed model series includes a waste load allocation model, an export coefficient model, a stream water quality model, and a genetic algorithm. This model series offers an optimized solution for determining the required removal levels of total suspended solids (TSS), the chemical oxygen demand (COD) at point and non-point pollution sources, and the source flows that require treatment to meet a given water quality target. The model series was applied during the summer and winter to the El-Qalaa basin in the western delta of the Nile River. Increased pollutant removal and treated fractions at point and non-point sources reduced violations of the TSS standards from 732.6 to 238.9 mg/L in summer and from 543.1 to 380.9 mg/L in winter. Likewise, violations of the COD standards decreased from 112.4 mg/L to 0 (no violations) in summer and from 91.7 mg/L to no violations in winter. Thus, this model is recommended as a decision support tool for determining a desirable waste load allocation solution from a trade-off curve considering costs and the degree of compliance with water quality standards.

A Bayesian method for comprehensive water quality evaluation of the Danjiangkou Reservoir water source area, for the middle route of the South-to-North Water Diversion Project in China

The Danjiangkou Reservoir is the water source for the middle route of the South-to-North Water Diversion Project in China. Thus, its water quality status is of great concern. Five water quality indicators (dissolved oxygen, permanganate index, ammonia nitrogen, total nitrogen, and total phosphorus), were measured at three monitoring sites (the Danjiangkou Reservoir dam, the Hejiawan and the Jiangbei bridge), to investigate changing trends, and spatiotemporal characteristics of water quality in the Danjiangkou Reservoir area from January 2006 to May 2012. We then applied a Bayesian statistical method to evaluate the water quality comprehensively. The normal distribution sampling method was used to calculate likelihood, and the entropy weight method was used to determine indicator weights for variables of interest in to the study. The results indicated that concentrations of all five indicators increased during the last six years. In addition, the water quality in the reservoir was worse during the wet season (from May to October), than during the dry season (from November to April of the next year). Overall, the probability of the water’s belonging to quality category of type II, according to environmental quality standards for surface water in China, was 27.7%–33.7%, larger than that of its belonging to the other four water quality types. The increasing concentrations of nutrients could result in eutrophication of the Danjiangkou Reservoir. This method reduced the subjectivity that is commonly associated with determining indicator weights and artificial classifications, achieving more reliable results. These results indicate that it is important for the interbasin water diversion project to implement integrated water quality management in the Danjiangkou Reservoir area.

한강수계에서의 다차원 시변화 유기물 및 영양상태 모델 연구

Multidimensional dynamic water quality model of organic matter and trophic state was applied to the Han River system. The model was calibrated using field measurement data obtained during the year of 2007. The model results showed reasonable performance in predicting temporal variations of TN, TP, Chl-a and BOD concentrations. The applied integrated modeling system can be effectively used to simulate water quality as well as hydrodynamic and water temperature for river-lake continuous system in the Han River. Utilizing the calibrated model, we analyzed the spatial and temporal distributions of TN, TP, Chl-a and BOD concentrations in the Han River system. The temporal variations of water quality at each river reach and lake were effectively simulated with the developed model and spatial distribution of water qualities in the Han River system could be compared. The multidimensional dynamic modeling system can simulate the water qualities of entire waterbody where Lake Paldang and the incoming flows are included using single modeling system. So it can be effectively used for integrated water quality management of the Han River system.

Attributiveness of a mass flow analysis model for integrated water resources assessment under data-scarce conditions

Nutrients in river systems originate from multiple emission sources, follow various pathways, and are subject to processes of conversion and fate. One approach to tackle this complexity is to apply balance-oriented models. Although these models operate on a coarse temporal and spatial scale, they are capable of assessing the significance of the different emission sources and their results can be the basis for developing integrated water quality management schemes. In this paper we propose and apply a methodology to evaluate the attributiveness of such model results with regard to the modelled emission pathways. The MONERIS (MOdelling Nutrient Emissions in RIver Systems) model is set up, assuming plausible ranges of emission levels from four principal sources. The sensitivity of model performance is computed and related to the contribution from the pathways. The approach is applied for a case study in the upper Western Bug catchment (Ukraine). Coefficient of determination (R(2)) is found insensitive against the model assumptions, at levels around 0.65 for nitrogen and 0.55 for phosphorous emissions. Relative mean absolute error is minimized around 0.2 for both nutrients, but with equifinal combinations of the varied emission pathways. Model performance is constrained by the ranges of the emission assumptions to a limited extent only.

Nitrate pollution of Neogene alluvium aquifer in Morogoro municipality, Tanzania

Concern over nitrate pollution of groundwater in integrated water quality management has been growing recently. The levels of nitrate in wells from septic tanks and urban agriculture with nitrogen fertilizers application may increase the potential groundwater pollution by nitrate. The purpose of this study was to determine the concentrations and spatial distribution of nitrate (NO3 -) in groundwater in Morogoro municipality. Groundwater samples were collected from 20 wells during wet season period in March-April 2010 in 6 wards namely Kihonda, Mji Mpya, Mafisa, Saba Saba, Boma and Kilakala. The spectrophotometer was used to measure the NO3 - concentration in water samples. The minimum and maximum nitrate levels were 1.4 and 32.5 mg/L respectively in the wards studied with an average of 7.76 mg/L. These results showed that all of the groundwater samples have NO3 - concentration below the Tanzania Bureau of Standards upper limit value and World Health Organization guideline of 75 mg/l and 50 mg/l respectively. Also, the level of nitrate concentration tends to decrease with depth for most of the places due to the anoxic condition that is available at the higher depth which facilitates the utilization of nitrate by anaerobic microorganisms.

A New Mindset for Integrated Water Quality Management for South Africa

The aim is to develop a conceptual model for aligning water resource quality and drinking water quality management. The model is based on the premise that good water quality is in everyone's best interests. Current management approaches attach responsibility for good water quality at a high level. The integrated water quality management approach “breaks down” the management of water quality into smaller management units and establishes a horizontal and vertical reporting framework through the application of a generic business process. The business process requires the identification of critical risk factors and critical control points in each management unit. The results of the project were the development of the water use cycle, as a context for the model, and the development of a basic integrated water quality management. A case study is currently underway in the Breede River catchment of the Western Cape Province of South Africa in order to refine the proposed model.

Optimal decision schemes for agricultural water quality management planning with imprecise objective

Agricultural activities are the main sources of water pollution to surface water and groundwater in rural areas. Extensive soil disturbance and application of fertilizer and manure in agriculture cause nonpoint source losses of soil and nutrients such as nitrogen and phosphorus. How to generate preferred decision schemes for agricultural activities that cause such nonpoint source water pollution is a critical issue for the decision makers. In this study, an inexact agricultural water quality management (IAWQM) model is developed and applied to a case study to generate optimal decision schemes for integrated water quality management within an agricultural system. The model is based on a hybrid fuzzy possibilistic robust programming approach, which improves upon the existing fuzzy possibilistic programming and fuzzy robust programming methods by allowing fuzzy information in the model's objective and constraints to be directly communicated into the optimization processes and resulting solutions. Optimal decision schemes for agricultural activities can be generated, including cropping area, manure/fertilizer applied, and livestock husbandry size, where implications of water quality/quantity restrictions for achieving regional economic development objectives are studied. The results of the case study indicate that useful information can be obtained through the proposed IAWQM model for providing feasible decision schemes, which reflect tradeoffs between economic and environmental considerations. The decision variables are useful for the decision makers to justify and/or adjust the decision schemes for agricultural activities through incorporation of their implicit knowledge on water quality management.

Comparison of macroinvertebrate community structure and driving environmental factors in natural and wastewater treatment ponds

Eutrophication still continues to be an issue of major concern for the protection of water quality, and accordingly, the European Union Water Framework Directive has set a minimum target for all waters where “good status” is defined as a slight departure from the biological community which would be expected in conditions of minimal anthropogenic impact. The use of constructed ponds for wastewater treatment aimed at achieving this target has shown to be an effective alternative to conventional systems in the farm landscape. Their applicability in these areas is of great interest since these ponds have the added potential to combine their wastewater treatment properties with that of biodiversity enhancement. This article focuses on exploring the community structure of both natural and constructed ponds used for wastewater treatment and the driving environmental factors. A total of 15 constructed and 5 natural ponds were sampled for aquatic macroinvertebrates and hydrochemistry in spring and summer 2006. Results showed that the most important factors responsible for the differences in the community structure between these two types of ponds were pH, vegetation structure and pollution levels. These gradients helped to structure a large proportion of the communities with some taxa being associated with the constructed ponds. These results highlight the potential contribution of constructed ponds used for wastewater treatment to the landscape biodiversity. The present findings also open the possibility for a more integrated management of water quality and biodiversity enhancement in farmland areas.

A SMART assessment of water quality partnership needs in Great Barrier Reef catchments

There has been considerable effort to set specific, measurable, achievable, realistic and timed (SMART) targets to halt the decline in the quality of water entering the Great Barrier Reef from diffuse sources. Less attention has focused on the assessment of collaborative delivery options needed to meet these targets. This article adapts the SMART criteria to assess partnership needs to deliver voluntary water quality management programs proposed in Queensland's Tully- Murray Water Quality Improvement Plan. This formative assessment enabled us to guide agricultural industry and local government sector focus group discussions. These discussions helped to determine if institutional arrangements adequately considered the specific purpose of proposed management activities, if measures of delivery success were compatible among collaborators, and if delivery costs were fairly distributed and achievable. The assessment also exposed the relevance of proposed management programs to each partner's activities and agendas, and how temporal attributes of partnership design and purpose could maximise the benefits of proposed actions. We suggest that the framework can help other practitioners and researchers to assess systematically how partnerships can be adaptively designed to ‘fit’ the objectives of integrated water quality management plans.

Integrated water quality management in Tolo Harbour, Hong Kong: a case study

Tolo Harbour is an almost land-locked semi-enclosed sea inlet with a narrow outlet in the South China Sea. With the rapid growth in economic development and urbanization, evidence of increasing eutrophication is seen by the drastic increase in the severity and frequency of algae blooms, which are closely correlated to the excessive nutrient loading. The bottom waters in Tolo Harbour exhibit serious dissolved oxygen depletion. A co-ordinated sequence of pollution control activities are being undertaken by the Hong Kong Government. Technological advances can be utilized in effective water quality management in the coastal zone. This paper presents the application of a robust three-dimensional numerical eutrophication model, integrating hydrodynamics with water quality, for simulation of the algal growth dynamics and water quality processes. After calibration and verification, the tool is used to predict different eutrophication scenarios as well as the effectiveness of alternative management solution strategies.