Narrow Results

The effluent discharge of domestic wastewater and industrial effluents into watercourses has necessitated the development of monitoring systems with the purpose of characterizing levels of pollution. Substantial levels of pollution in emerging nations have been exacerbated by rapidly growing populations and inefficient enforcement of sustainable management initiatives. The Water Quality Index (WQI) can help fill the gap between water quality reporting and monitoring by offering a simple and effective way to assimilate and communicate results from a large amount of data. WQIs are the kind of communication tools that can facilitate knowledge sharing between scholars and the general public. The degradation of natural water resources, such as lakes, streams, and estuaries, is the most significant problem facing humanity. Water that is not clean has far-reaching effects on all aspects of life. Water resource management is therefore essential if it is to maximize water quality. If data are analyzed and water quality can be predicted in advance, water pollution may be efficiently addressed. Although this subject has been the subject of numerous earlier studies, additional research is still required to fully understand the effectiveness, reliability, accuracy, and application of the present approaches to water quality management. In this research work, a comprehensive review has been conducted on water quality assessment using artificial techniques. It reviews 75 research works on water quality analysis. The data collected in each research work have been analyzed. Moreover, the type of water resource surface water, groundwater, drinking water as well has been analyzed. The parameters considered in each work are “Dissolved Oxygen (DO), Potential of Hydrogen (pH), Biochemical Oxygen Demand (BOD), Total Dissolved Solids (TDS), and Chemical Oxygen Demand (COD), chloride, hardness, alkalinity, nitrate–nitrite”. In addition, the Artificial Intelligence technique utilized for water quality analysis is also assessed. Finally, the research gaps identified in water quality detection are exhibited.

Present investigation deals with the evaluation of DO, BOD and COD of six surface water resources of Bikaner district which fall in arid region of Rajasthan – a part of Great Indian Desert, to determine pollution status. Water sample analysed for two years 2008-2009 showed these parameters beyond the limit of standard prescribed by WHO. These parameters also showed great seasonal fluctuation, indicating the degree of organic pollution more during summer season and least during winter season.

We review 15 forest watershed protection programs in the United States in which a local government agency or water provider collects payments from downstream service beneficiaries, such as water consumers, and pays upstream forest landowners for provision of watershed services. We describe the features of these Payments for Watershed Services (PWS) programs, focusing on funding sources, how the payment mechanisms work, and outcomes achieved. We also assess the extent to which the programs adhere to the economic principles that are associated with efficient or cost effective PWS schemes. In general, we find that payments in the programs do not closely reflect the marginal value of the service provided. Payments received by landowners mainly reflect the landowners’ opportunity costs. Fees paid by water consumers are set to yield revenue targets and/or reflect the avoided cost of additional water filtration and treatment. The programs appear to yield societal benefits, primarily through cost savings, but data from program outcomes is limited and more rigorous analysis of both the benefits and costs would be worthwhile.

Isotopes of hydrogen and oxygen in different water bodies were investigated to understand the isotopic characteristics in the Upper Indus River Basin, Ladakh. A total of 50 water samples were collected from the main river, tributary, glaciers, and groundwater in this study. The Indus River and its major tributaries (such as the Zanskar, Nubra, and Shyok rivers) are characterized by relatively lower δ¹⁸O values, whereas TangTse and other small streams contributing to the Indus are relatively enriched in δ¹⁸O. The δ¹⁸O and δD values of mainstream, tributaries, streams, groundwater, and glaciers ranged from −15.1‰ to −12.3‰, −16.5‰ to −12‰, −13.8‰ to −12‰, and −17.3‰ to −11‰ for δ¹⁸O and −105.9‰ to −89.9‰, −118.8‰ to −77.1‰, −98.2‰ to −85.3‰ and −118.8‰ to −67.5‰ for δD. The local water line for the IRB was found to be δD = 8.3 δ¹⁸O + 19.9, which suggests the meteoric origin of water and minimal evaporation in the river water. The δ¹⁸O values of river water vary from −15.7‰ to −6.9‰ with a general enrichment in δ¹⁸O from source to sink. The obtained d-excess and δ¹⁸O values suggest that the main source of moisture in the studied region is mainly from westerlies and southwest monsoons. In the upper reaches of the Indus river, δD decreased longitudinally due to ice melting and an increasing amount of glacier meltwater as elevation decreases. The surface water originates from not only atmospheric precipitation but also glacial/snow meltwater, especially in the Zankar range, the upper reaches of the Suru river, and the Drass river. The results of this study provide a baseline for hydrological research in the Indus River Basin.

The present study investigated the physicochemical and metal concentrations in water samples collected from Pasur River, Bangladesh. Mongla seaport stands on the bank of this river. Many industries and other commercial sectors situated in this port area are discharging their wastes into the river without proper treatment. The concentration range of TSS, chloride, iron (Fe), and manganese (Mn) were from 363.2 to 1482.7, 108.2 to 708.93, 1.13 to 2.75, and 0.19 to 1.41 mg/L, significantly exceeding the health-based guideline of WHO and Bangladesh (DoE) standards. The average pH value was 8.73, higher than the WHO and DoE standard limit. The water quality evaluation indices such as Metal Index (MI), Comprehensive Pollution Index (CPI), and Water Quality Index (WQI) were used to determine the pollution levels of the Pasur River. WQI (ranging from 391.3 to 1336.1), CPI (6.71 to 23.13), and MI (7.23 to 23.27) were very high and greatly exceeded standard limits indicating that the Pasur River water is highly polluted. The results of Pearson correlation analysis, principal component analysis (PCA), and cluster analysis (CA) indicated that the sources of pollutants were both geogenic and anthropogenic. The spatial distribution of quality indices and cluster groups indicates that the studied river’s urban and seaport areas were more contaminated. The primary anthropogenic sources are municipal wastewater, industrial effluents, runoff from an agricultural area, local bazar, car garage wastes, highway, and stormwater runoff.

It has been reported by the present authors that introduction of water vapor to the purge gas can give quick decontamination of tritium from the surface of various materials through the isotope exchange reaction between water vapor in the gas phase and tritium on the surface. At collection of contaminated wastes with tritium, it is required by regulation to know the amount of tritium trapped to surface and bulk of disposal materials. However, it is difficult to measure the amount of tritium on the surface of materials such as tritium gas cylinder or pipes and reaction vessels in a tritium handling system. In this study, several experiments were performed applying the isotope exchange reaction between water vapor in the gas phase and tritium in the surface water to estimate the amount of tritium on the inner surface of used tritium gas cylinder made of aluminum alloy, and the results obtained from these experiments were compared with result of the smear method. Observed value for the amount of tritium on the surface of the aluminum alloy was similar to the value estimated using the trapping capacity of water on aluminum obtained by our previous experimental results. It is confirmed that injection of a little amount of water to the system makes it possible to extract whole tritium trapped on the inner surface of gas cylinder, though the smear method could not give quantitatively reliable results for measure the amount of tritium on the surface.

Active and abandoned mines in Kota Tinggi, Johor, have raised environmental concern over heavy metal contamination. Arsenopyrite in tailing and ore body could be the source for acid water generation and subsequent acid mine drainage processes. According to the hydrochemistry facies classification, groundwater has Na-K-Ca, HCO3 character with trend toward sulfatic, near mining area. Two water quality indices have been used for groundwater and surface water assessment, which reveal low heavy metal dissolution, both in tailing and working sites. According to Ficklin diagram, surface water lies in near neutral- high metal content boundary, that shows relatively high dissolved heavy elements in mining area. When compared to the INTERIM IIA/IIB standard for supply water in Malaysia, it shows that Cu is higher than the limit and As is almost reaching the threshold level.

The 1906 Convention and the 1944 Treaty establish the distribution of surface water of the Rio Grande (RG), Colorado, and Tijuana Rivers between the United States and Mexico. Neither of these treaties addresses groundwater management. Only Minute 242 to the 1944 Treaty, regulates salinity for groundwater. Specifically, Minute 242.5 establishes that there is a lack of “conclusion by the Governments of the United States and Mexico for a comprehensive agreement on groundwater in the border areas.” The lack of regulation has contributed to overdraft and degradation of the water quality in several aquifers along the US–Mexico border. Recommendations for an institutional and legal framework under an umbrella agreement, addressing water bank as allocation tool, attempt to fill the legal vacuum of international and interstate groundwater management in the US–Mexico border region. In addition, these recommendations can be adapted to other transboundary basins around the world.