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Practice of source treatment
Published in Xiaoling Lei, Bo Lu, Integrated Water Environment Treatment, 2021
At present, Chongqing water environment problems mainly involve point source pollution and non-point source pollution problems. The point source pollution means that pollutants are discharged into water from centralized places, mainly including domestic pollution and industrial pollution. As for Chongqing main urban area, the point source pollution mainly has the following characteristics: There are relatively less industrial enterprises in Chongqing main urban area and the management on sewage discharge of industrial enterprises is relatively stricter that the industrial wastewater can only be discharged into the urban sewage pipe network after being treated and meeting relevant discharge standards. Therefore, the point source pollution in Chongqing main urban area is mainly domestic pollution.The sewage network coverage rate has not reached 100% yet, so the sewage in some areas is still discharged in a unorganized way or discharged into storm sewer.Some old sewage pipes exist the problem of serious leakage.The treatment capacity of existing sewage treatment plants is limited.
Valuation of Selected Water-Related Ecosystem Goods and Services
Published in Robert A. Young, John B. Loomis, Determining the Economic Value of Water, 2014
Robert A. Young, John B. Loomis
Environmental economists have devoted considerable effort to the problem of managing water pollution. Water pollution originates from either point sources or nonpoint sources. Point source pollution is emitted from a single pipe or ditch through which the pollutant is transported to a water body. Regulation and monitoring of compliance with regulations can more easily focus on the point of discharge. Nonpoint sources are those for which there exists no single source of pollutant discharge. They are most often associated with human uses of land such as farming, forestry, and construction. Soil particles eroded from farm or forest lands and washed into lakes or streams are a primary example. This problem is exacerbated in farming areas with heavy precipitation or excessive field irrigation. In these cases, runoff from agriculture also includes fertilizers and pesticides that are carried off the soil surface into surface water bodies or percolate into groundwater deposits, some of which are used for drinking water. However, erosion of soil and organic matter also originates from natural processes, e.g. organic matter from forests or dissolved mineral solids (salinity) from both surface and underground water contact with sedimentary rock formations. The difficulties of separating out natural background sources from human-caused sources along with the diffused nature of nonpoint source pollution has made it challenging to achieve cost-effective optimal control. These challenges are endemic to both developed countries (see U.S. Environmental Protection Agency 2003; Malik et al. 1994) and developing countries such as China (Wang and Cao 2005).
Evaluation of Water and Its Contaminants
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 5, 2017
William J. Rea, Kalpana D. Patel
Point source pollution refers to a direct source of pollution, such as a pipe or other vessel. Early industries such as pulp and paper companies located in the Great Lakes region believed that anything could be dissolved in water, and thus neutralized. As a result, many wastes (such as mercury) were dumped into the Great Lakes. There have also been observations of fecal matter pollution from sewage, which results in harmful bacteria such as E. coli and enterococci.94 Both sewage and other organic and inorganic wastes cause the water quality to decline and bacteria growth to increase.95
Integrated GIS and multivariate statistical approach for spatial and temporal variability analysis for lake water quality index
Published in Cogent Engineering, 2023
Poornasuthra Subramaniam, Ali Najah Ahmed, Chow Ming Fai, Marlinda Abdul Malek, Pavitra Kumar, Yuk Feng Huang, Mohsen Sherif, Ahmed Elshafie
Point source pollution is referred to as pollution from a known point of discharge or fixed outlet and can be released into water bodies in pipes or man-made drainage (Gyawali et al., 2013). Some examples of point source pollution are pipe discharges, industrial outflows, tributaries, industrial or municipal wastewater treatment plant outflows. Since possible contaminants from a point source can be easily monitored by measuring discharge and pollutant levels from an identified discharge point, its impact is easy to define and regulate. The focus over the previous years of research work was to address point source pollution through managing the known point of discharges, such as urban wastewater effluent, as described by 2010) and Perona et al. (1999) which was found to have been successfully under pollution control and management.
The social discourses on market-based instruments to manage non-point-source water pollution in the Oldman River basin, southern Alberta
Published in Water International, 2018
Gillian Kerr, Henning Bjornlund
Ensuring adequate water quality in rivers and other water bodies – for ecosystems, human consumption and economic use – is becoming an increasingly urgent issue across the world (United Nations, 2011). Two main categories of pollution influence water quality: point-source and non-point-source. Point-source pollution is relatively easy to manage, as there is a specific source of the pollution, such as a sewage treatment plant, which authorities can effectively monitor and, therefore, regulate (Russell & Clark, 2006), whereas non-point-source pollution is caused by disparate sources, which it is far more difficult to monitor and therefore to regulate (Oldman River Basin Water Quality Initiative, 2002). Non-point-source pollution is the predominant water quality issue in developed countries, and it has increased management challenges for governments (Dai, Sun, Zhang, & Guo, 2015; Graham, Schempp, & Troell, 2011).
Ecological security evaluation for Changtan Reservoir in Taizhou City, East China, based on the DPSIR model
Published in Human and Ecological Risk Assessment: An International Journal, 2023
Lingxi Li, Peiyue Li, Song He, Rui Duan, Fei Xu
The pollutant emissions from point pollution sources and nonpoint pollution sources in the watershed are shown in Figure 4. Point source pollution mainly includes urban industrial emissions and emissions from large-scale farms, as well as centralized treatment and discharge of urban and rural domestic sewage. Nonpoint source pollution includes livestock and poultry free-range discharge, agricultural runoff pollution discharge, direct emissions from rural life, urban runoff discharge, and dry and wet deposition of reservoirs. COD, TN, and TP mainly come from urban and rural domestic sewage discharges and agricultural production loss (Figure 4).