Water Pollution Accidents Research Articles

On real-time risk evaluation of accident in water quality control zone

The sudden water pollution is a main type of environmental accident. The time evolution risk of sudden water pollution accident is very important to select real-time measures to effectively reduce the temporal growing risk. The traditional evaluation methods have shortages of describing the evolution process of accident. This paper proposes a real-time risk evaluation method with real-time weight and index to predict the temporal growing risk of sudden pollution accident. The open channel of the Luanhe water supply system in Tianjin is selected as an example to evaluate the temporal risk evolution of the accident. The study provides a reasonable and effective method for the real-time evaluation of sudden pollution accident.

An Improved Contaminant Source Identification Method for Sudden Water Pollution Accident in Coaster Estuaries

Jing, L.; Kong, J.; Wang Q., and Yao Y.T., 2018. An improved contaminant source identification method for sudden water pollution accident in coaster estuaries, China. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 946–950. Coconut Creek (Florida), ISSN 0749-0208.This paper presents a method for quickly and accurately identifying contaminant source in estuary region, characterized by decoupling solving releasing time, location and density of source problems, respectively. The method firstly gets the rough source releasing time by analyzing the typical double peak phenomenon in tidal estuary region, and then presents the rough position of source by using Lagrange tracing scheme. The rough position makes up the deficiency of priori information in traditional Genetic Algorithm (GA). And then, according to the correlation between the measured and calculated concentration at measuring point, a high resolution mass transportation and an optimization models are operated repeatedly and alternatively. In order to increase the efficiency of searching optimal parameters, the Genetic Algorithm is improved by introducing a weighting factor based on the precision improvement trend. Such an optimization model can effectively reduce the calculation burden when parameters are increased in demand. This model has been successfully applied in an accident case in Quanzhou Bay of China. Simulated results confirm the model's merits in reasonably identifying relevant unknown parameters. The convergence of present model is more efficient in searching for the optimal parameters with less iteration times nearly half the traditional Genetic Algorithm. This model is high efficiency and has great practical significance in dealing with emergent water pollution in estuary and coastal areas.

Public Awareness of Drinking Water Safety and Contamination Accidents: A Case Study in Hainan Province, China

To understand public awareness about drinking water safety and water contamination accidents in rural areas of China, two rural counties of Hainan Province were selected as pilot sites for investigation. We explored the degree of public satisfaction with drinking water quality, public trust of drinking water safety, and public awareness about drinking water problems and solutions. The results showed that 80.3% of respondents were satisfied with the quality of their drinking water. About 78.8% of respondents paid special attention or comparatively high attention to drinking water quality and contamination accidents, especially regarding potential damage to the human body and health, the influence scope, and the causes of accidents. A total 52.4% of respondents solved drinking water problems by themselves; few respondents complained to the health department or called the local telephone hotline. Age and sex did not play significant roles in the degree of public satisfaction with water quality or in the public perception of water pollution accidents; however, residents in rural areas within a drinking water quality monitoring network were more satisfied with their drinking water quality and more aware of drinking water contamination accidents than in areas outside of such a network. Respondents with higher education levels had greater awareness than those with lower education levels with respect to water quality and water pollution accidents.

Assessing emergency regulation technology in the Middle Route of the South-to-North Water Diversion Project, China

The Middle Route of the South-to-North Water Diversion Project is important for China. Any sudden water pollution accident along the route would threaten normal water supply. We studied four technologies (hydrodynamic and water quality simulation, source identification, emergency regulation, and evaluation of emergency measures) and developed and implemented a decision support system that provides technical support in managing pollution accidents. The achievements, which include four technologies and a system, have practical significance for emergency management in the Middle Route as they can help deal with accidents and policy formulation, and can be applied to other water transfer projects.

Risk Assessment of Pollution Emergencies in Water Source Areas of the Hanjiang-to-Weihe River Diversion Project

[Objective] This study quantitatively evaluated risk probabilities of sudden water pollution accidents under the influence of risk sources, thus providing an important guarantee for risk source identification during water diversion from the Hanjiang River to the Weihe River. [Methods] The research used Bayesian networks to represent the correlation between accidental risk sources. It also adopted the sequential Monte Carlo algorithm to combine water quality simulation with state simulation of risk sources, thereby determining standard-exceeding probabilities of sudden water pollution accidents. [Results] When the upstream inflow was 138.15 m3/s and the average accident duration was 48 h, the probabilities were 0.0416 and 0.0056 separately. When the upstream inflow was 55.29 m3/s and the average accident duration was 48 h, the probabilities were 0.0225 and 0.0028 separately. [Conclusions] The research conducted a risk assessment on sudden water pollution accidents, thereby providing an important guarantee for the smooth implementation, operation, and water quality of the Hanjiang-to-Weihe River Diversion Project.

An Ontology-Underpinned Emergency Response System for Water Pollution Accidents

With the unceasing development and maturation of environment geographic information system, the response to water pollution accidents has been digitalized through the combination of monitoring sensors, management servers, and application software. However, most of these systems only achieve the basic and general geospatial data management and functional process tasks by adopting mechanistic water-quality models. To satisfy the sustainable monitoring and real-time emergency response application demand of the government and public users, it is a hotspot to study how to make the water pollution information being semantic and make the referred applications intelligent. Thus, the architecture of the ontology-underpinned emergency response system for water pollution accidents is proposed in this paper. This paper also makes a case study for usability testing of the water ontology models, and emergency response rules through an online water pollution emergency response system. The system contributes scientifically to the safety and sustainability of drinking water by providing emergency response and decision-making to the government and public in a timely manner.

Optimization of Water Reservoir Operation to Minimize the Economic Losses Caused by Pollution

The pollution of river water as a result of an accident can cause different types of serious damages to people, aquatic life, agricultural land, plants, and animal ecosystems. Apart from tragic events such as deaths or injuries, the accidental water pollution causes important economic losses. One effective measure is to reduce the concentration of the pollutant in the river water by adding clean water released from reservoirs placed on tributaries of the river. In this paper, we focus on finding an optimal operation of the water reservoirs (such as opening/closing time of the gates) with the goal of minimizing the total cost of the economic damages. Two components of the total cost are defined and quantified: the cost of the water used to achieve dilution and the losses caused by the existence of the pollutant in a certain concentration in the water. This problem is formalized as a non-linear multi-objective simulation-optimization model, subject to constraints. The solution is evaluated for a real use case (Jijia River, respectively, Dracsani and Halceni reservoirs in North–East Romania). The results are presented for two experiments. They show that by using the proposed optimization solution, the total cost of economic losses may be reduced by almost six times as compared with an empirical operation of the reservoirs and by almost $10\times $ if no dilution takes place.

基于模拟–优化模式的梯级水库群突发水污染事件应急调度研究

基于模拟–优化模式的梯级水库群突发水污染事件应急调度研究

Discussion on Reservoir dispatch during a sudden accident of water pollution in a long distance river

A mathematical model of river hydrodynamics with cascade reservoirs and pollutant has been established and verified by using analytic solutions of partial differential equation for transportation and diffusion. Ten dispatch schedules of single or multi- reservoirs have been set up and executed according to that a pollution accident occurred upstream or downstream to a reservoir. It shows that which dispatch schedule should be selected was decided by sensitive factors of a target river segment downstream. A dispatch model of large flux with short time duration by utilizing a reservoir nearest to the segment was more appropriate for which was more sensitive to concentration than other factors, while a model of appropriate flux discharge with long time duration was more suitable for those being more sensitive to extra concentration retention of pollutants. Compared with a single reservoir dispatch, multi-reservoirs have larger effective storage capacity to reduce the loss by a sudden water pollution accident better by supplement water step by step from upstream to downstream.

Source identification of accidental water pollution in a tidal river network based on a water environment model and database

Source identification of accidental water pollution in a tidal river network based on a water environment model and database

A simulation program on change trend of pollutant concentration under water pollution accidents and its application in Heshangshan drinking water source area

With the rapid development of the economy in recent years, water pollution accidents have occurred frequently, and accidents that have occurred in drinking water source areas in particular have seriously affected public health and social safety. The objective of this study is to develop a program to predict the diffusion and migration processes of pollutants after water pollution accidents and apply it to the Heshangshan drinking water source area. Taking Cd as a typical pollutant, the results indicated that Cd concentrations at the water intake reached a maximum value of 1.2490 × 104 mg/L at 14.08 min after a hypothetical accident, and the time when the area lost the function of drinking water supply was from 8.35 min to 24.23 min after the accident. Regarding the drinking water source area, the Cd concentration exceeded the related standard during the period from 7.29 min to 41.47 min after the accident, which indicated that it was polluted seriously by the accident for that duration. Moreover, the pollutant entered into the study area at 7.00 min after the accident and had passed through at 45.63 min after the accident, which demonstrated that emergency measures should be taken for this duration. The developed simulation program could simulate the spatial distribution and temporal change of pollution, calculate maximum concentration of pollutants, present pollution scope and time, and forecast diffusion and transport processes. This study will give relative researchers and managers a reference and tool for pollutant migration and water resources management after water pollution accidents.

Removal of Organic Pollutants from Water Using Superwetting Materials.

The frequent occurrence of water pollution accidents and the leakage of organic pollutants have caused severe environmental and ecological crisis. It is thus highly imperative to find efficient materials to solve the problem. Inspired by the lotus leaf, superwetting materials are receiving increasing attention in the field of removal of organic pollutants from water. Various superwetting materials have been successfully generated and integrated into devices for removal of organic pollutants from water. On the basis of our previous work in the field, we summarized in this account the progress of removal of (1) floating and underwater insoluble, (2) emulsified insoluble, and (3) both insoluble and soluble organic pollutants from water using superwetting materials including superhydrophobic & superoleophilic materials, superhydrophilic & underwater superoleophobic materials, and materials with controllable wettability. The superwetting materials are in the forms of 2D porous materials, 3D porous materials and particles, etc. Finally, the current state and future challenges in this field are discussed. We hope this account could shed light on the design of novel superwetting materials for efficient removal of organic pollutants from water.

Early Warning and Forecasting System of Water Quality Safety for Drinking Water Source Areas in Three Gorges Reservoir Area, China

Nowadays, the effects of water pollution accidents on water quality safety and regional residents’ living have attracted worldwide attention. Therefore, the objective of this research is to propose an early warning and forecasting model and develop a visual system of water quality safety for drinking water source areas in the Three Gorges Reservoir Area under accident conditions. Based on an Instantaneous Point Source Two-dimensional Water Quality Model and the security requirements of water quality, an early warning and forecasting model was presented, and then the system was advanced by a MATLAB platform. In addition, a hypothetical case was also carried out for the Fenghuangshan drinking water source area. Within 0.040 h to 0.096 h after the accident, the water quality could meet the standard, and the warning level was primary and intermediate, sequentially. From 0.096 h to 11.960 h after the accident, the pollutant concentration exceeded the standard, under which conditions advanced warning started. Then the intermediate and primary warnings restarted in sequence until the pollutant concentration decreased to the background value. Therefore, the proposed model could accurately predict the spatial-temporal change trend of pollutant concentration, and the developed system could efficiently realize early warnings and the forecasting of water quality safety.

Simulation-based risk analysis of water pollution accidents combining multi-stressors and multi-receptors in a coastal watershed

As environmentally important ecosystems, coastal watersheds are vulnerable to abrupt water pollution events. Previous researches of accidental pollution in coastal watersheds mostly focused on oil leakages from mobile sources, pipelines, or stationary sources; however few considered chemical pollution accidents from terrestrial stationary sources. The present paper uses one-dimensional and MIKE 21 convection-diffusion models to simulate chemical transport processes in coastal rivers and in near-shore seas. Based on the simulation results, a Coastal Accidental Water Pollution Risk Analysis (CAWPRA) method is proposed. CAWPRA considers acute pollution risk passing from upstream to downstream, and to estuary and near-shore sea areas in a coastal watershed. The method is applied to Beihai City, a typical coastal area of rising economic development, to provide a risk assessment based on simulations of water accidental pollution from terrestrial stationary sources. A leakage event of hydrochloric acid from Wenkehaiyang Co. Ltd is taken as an example. Water quality simulation results indicate that after 6, 12, 18, and 24h the peak concentrations of hydrochloric acid would be 3.72, 0.91, 0.75, and 0.68mg/l, respectively, and accordingly, the areas of coastal water exceeding the seawater quality standard would be 5.56, 4.92, 9.71, and 45.01km2, respectively. Hydrochloric acid would reach Dangjiang Mangrove Nature Reserve a time 14h after the leakage event first occurred. The resultant map indicates high, medium, and low risk sub-areas. The map is useful at identifying the most risky sources and the most vulnerable receptors for the Beihai coastal watershed.

Tracking historical mobility behavior and sources of lead in the 59-year sediment core from the Huaihe River using lead isotopic compositions

A historical perspective of past 59 years (1955–2014) for contamination and isotopic composition of Pb in sediment core system of the Huaihe River, Huainan City, Anhui Province of China is presented. Detailed investigation regarding changes in Pb sources, enrichment factor, sequential extraction and isotopic analysis revealed that high Pb concentrations were detected along the core, especially during the first two decades (1955–1974). Large variations in Pb isotopic compositions were observed, with 206Pb/207Pb and 208Pb/207Pb values ranging from 1.1504–1.1694, and 2.0817–2.1380, respectively. Diverse Pb sources were identified for sediment contamination over the time. Among anthropogenic sources, metallurgic dust and leaded petrol were on top during 1955–1974, especially when the Great Leap Forward Movement (1958–1960) was in progress in China, the time numerous small industries were established without wastewater treatment facility. However, coal and coal combustion were recognized as the primary sources of Pb emissions for the recent four decades (1974–2014) due to tremendous increase of coal consumption for power and heat generation. Unleaded vehicle exhaust, waste incineration and industrial emission were also sources of Pb during the years 1974–2014. Our estimates based on geochemical and lead isotopic approaches have shown that anthropogenic Pb contributions varied from 4.35 to 92.01%, and 13.28–99.06%, respectively. Assessment of lead speciation indicated an overwhelming presence of reducible fraction (Fe-Mn hydro-(oxides)) in the sediment core, except during 1995–1997, which was thought to be affected by water pollution accidents caused by heavy rainfall.

Sudden water pollution accidents and reservoir emergency operations: impact analysis at Danjiangkou Reservoir

ABSTRACTDanjiangkou Reservoir is the source reservoir of the Middle Route of the South-to-North Water Diversion Project (MRP). Any sudden water pollution accident in the reservoir would threaten the water supply of the MRP. We established a 3-D hydrodynamic and water quality model for the Danjiangkou Reservoir, and proposed scientific suggestions on the prevention and emergency management for sudden water pollution accidents based on simulated results. Simulations were performed on 20 hypothetical pollutant discharge locations and 3 assumed amounts, in order to model the effect of pollutant spreading under different reservoir operation types. The results showed that both the location and mass of pollution affected water quality; however, different reservoir operation types had little effect. Five joint regulation scenarios, which altered the hydrodynamic processes of water conveyance for the Danjiangkou and Taocha dams, were considered for controlling pollution dispersion. The results showed that the spread of a pollutant could be effectively controlled through the joint regulation of the two dams and that the collaborative operation of the Danjiangkou and Taocha dams is critical for ensuring the security of water quality along the MRP.

Effect of typhoon with extreme precipitation on mountain reservoir drinking water treatment: a case study in Ningbo, China

ABSTRACTDue to frequent drinking water pollution accidents in the past decade, it is common that mountain reservoirs were used as the source of drinking water in China. However, some coastal areas frequently suffer from typhoon with extreme precipitation, which results in the water quality deterioration of the reservoirs. The influence of typhoons with extreme precipitation on Jiaokou reservoir and the emergency treatment process of Maojiaping water treatment plant in the past three typical typhoons with extreme precipitation from the year of 2012–2015 were studied. It was found that the degradation of water quality, such as the increase of turbidity and bacteria index, may not merely appear during the events, but last for several days. Changing the dosage of water purification agent, such as coagulant and disinfectant at right time and place may be an efficient emergency water treatment process. Based on the analysis of water quality variation rule during and after the events, it was also found that emer...

Acceptable Risk Analysis for Abrupt Environmental Pollution Accidents in Zhangjiakou City, China.

Abrupt environmental pollution accidents cause considerable damage worldwide to the ecological environment, human health, and property. The concept of acceptable risk aims to answer whether or not a given environmental pollution risk exceeds a societally determined criterion. This paper presents a case study on acceptable environmental pollution risk conducted through a questionnaire survey carried out between August and October 2014 in five representative districts and two counties of Zhangjiakou City, Hebei Province, China. Here, environmental risk primarily arises from accidental water pollution, accidental air pollution, and tailings dam failure. Based on 870 valid questionnaires, demographic and regional differences in public attitudes towards abrupt environmental pollution risks were analyzed, and risk acceptance impact factors determined. The results showed females, people between 21–40 years of age, people with higher levels of education, public servants, and people with higher income had lower risk tolerance. People with lower perceived risk, low-level risk knowledge, high-level familiarity and satisfaction with environmental management, and without experience of environmental accidents had higher risk tolerance. Multiple logistic regression analysis indicated that public satisfaction with environmental management was the most significant factor in risk acceptance, followed by perceived risk of abrupt air pollution, occupation, perceived risk of tailings dam failure, and sex. These findings should be helpful to local decision-makers concerned with environmental risk management (e.g., selecting target groups for effective risk communication) in the context of abrupt environmental accidents.

Online Classification of Contaminants Based on Multi-Classification Support Vector Machine Using Conventional Water Quality Sensors.

Water quality early warning system is mainly used to detect deliberate or accidental water pollution events in water distribution systems. Identifying the types of pollutants is necessary after detecting the presence of pollutants to provide warning information about pollutant characteristics and emergency solutions. Thus, a real-time contaminant classification methodology, which uses the multi-classification support vector machine (SVM), is proposed in this study to obtain the probability for contaminants belonging to a category. The SVM-based model selected samples with indistinct feature, which were mostly low-concentration samples as the support vectors, thereby reducing the influence of the concentration of contaminants in the building process of a pattern library. The new sample points were classified into corresponding regions after constructing the classification boundaries with the support vector. Experimental results show that the multi-classification SVM-based approach is less affected by the concentration of contaminants when establishing a pattern library compared with the cosine distance classification method. Moreover, the proposed approach avoids making a single decision when classification features are unclear in the initial phase of injecting contaminants.

A 59-year sedimentary record of metal pollution in the sediment core from the Huaihe River, Huainan, Anhui, China.

An approximately 59-year (1955-2014) sedimentary record of metal elements (Cu, Pb, Zn, Ni, Co, Mn, and Fe) in a sediment core, collected from the Huaihe River, Huainan City, Anhui Province, China, was reconstructed by using 210Pb geochronology. Copper, Zn, Ni, Co, and Mn evaluated by enrichment factor (EF) indicated minor contamination due to water pollution accidents of the Huaihe River that occurred in 1990s and 2004. Lead presented the most severe pollution among the metals studied, especially during 1957-1974. The use of leaded petrol and atmospheric deposition of coal combustion flue gases could have contributed to Pb contamination. In spite of the general good quality (mean sediment pollution index (SPI) 35.69) of the sediment core evaluated by SPI based on the principal component analysis, worse sediment qualities in the upper section (<6cm, 2004) were still observed, suggesting intensive human activities causing the increasing concentrations of metals in recent decades.