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Quality of water, along Mandal headquarters of a coastal district of Andhra Pradesh, India, was assessed prior to and past rainfall season to determine water's acceptability for consumption using water quality index (WQI). The present work involved collecting groundwater samples from Mandal headquarters' locations present in the entire district. All the samples were analysed in a comprehensive way for ten physicochemical parameters, including pH, magnesium, calcium, chloride, sulphate, nitrates, total dissolved solids, fluoride, potassium, and sodium. The geographical information system was used for mapping sampling sites. The coordinates of sample collection areas were recorded employing GPS. Correlation matrices for cation–anion were illustrated and from the qualitative results of the samples. Results indicate that WQI prior and past-rainfall seasons ranged from 37.53 to 312.46; 42.04 to 211.89 in 2016, while for 2017, these were in the range of 25.01 to 137.06; 30.06 to 228.83. The present study's WQI values indicate that the water samples possess poor quality, and no fluoride contaminations were observed. The analysis suggests appropriate treatment of sub-surface water from the study site before consumption.

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Due to rapid urbanization and industrialization, water demand has increased worldwide. The availability of potable water is becoming more difficult in the global scenario. Hazardous pollution disposal by the industries to the nearest stream and search for the facile environmentally friendly technologies capable of treating these pollutants become more challenging. Effluent disposal consisting of the dyes without proper pre-treatment adversely affects the aquatic life and ecological system as they are carcinogenic and highly toxic. Dyes in the water are becoming a significant problem in the current scenario and attracted many researchers to research the current topic. Even though the conventional treatment options are available for treating polluted water, still they are not enough for the demand and supply. Thus, new state-of-the-art technologies are required to meet the demand and supply. Titanium dioxide nanofibers synthesized by electrospinning techniques have proven to be new nanomaterials gaining prominence in science. Several researchers are using these fibres by fabricating them into a thin film for pollutant removal and water treatment. They are gaining much importance as they perform best in treating water containing both organic and inorganic loads. The present review provides insights into the background and the origin of the electrospun nanofibers and preparation mechanisms. Further, we identified 25 widely used titanium dioxide electrospun nanofibers with various combinations in removing the dyes from the aqueous medium.

It is estimated 90% of the available water resources will be expended in 15 years and by 2025, nearly 60% of the world population will have scarcity of water if the rate of consumption continues at its present level. The mounting use of pharmaceuticals, with enhanced production, have driven these industrial effluents into so-called emerging pollutants that have become a new environmental problem. Pharmaceutical wastewater, specifically categorized by complex components, are ending up polluting natural water bodies, making it necessary to remove such substances from the wastewaters to prevent harm to the natural environment. Amid options available for treating these effluents, biological processes are cost-effective and environmentally safe alternatives to chemical methods. One of the recent advances includes use of membrane technology. Among these, membrane bioreactor and reverse osmosis technologies are becoming advanced and promising options for wastewater treatment, and reuse at a reduced price is making it economically feasible.

: Many studies reported the application of natural coagulants in removing pollutants with the help of the coagulation process, and coagulants showed their efficiency in comparison to the literature available. Yet, the utilization or acceptance of these coagulants in treating industrial wastewater is very low. Thus, there is a need for a strategy for enhancing the potential usage of coagulants for water treatment, presenting prevailing options and efforts for the development of coagulants. The utilization of coagulants can be improved by showing their efficiency in comparison to the advanced treatment technologies available in the present scenario. The coagulation efficiency with natural coagulants can be enhanced by mongrelizing the coagulants with other coagulants, enhancing the purity during extraction procedures, and by coalescence of coagulants. However, the research on natural coagulants are quite encouraging, perception of sustainable assessment studies revealed that commercialization/acceptance of coagulants for treatment options are hindered by their applicability and feasibility in real-time applications, and utilization of coagulants ignore the socioeconomic, ecological and technical aspects. The present review mainly focuses on the issues related to natural coagulants for clarifying the uncertainties and simultaneously moving the water industries to be more sustainable.

Water quality along Coastal Zones of Srikakulam District in Andhra Pradesh, India was analyzed through seasons of pre and post of monsoon for determining water appropriateness towards consumption by means of water quality index (WQI). Present study included collection of sub-surface water samples from sampling sites which are designated as Mandal headquarters across the coastal line. Towards developing WQI, physicochemical analysis of samples was determined considering nine important parameters that included physical parameters like total dissolved solids, chemical parameters like pH, conductivity, ionic parameters such as calcium and magnesium, sodium and potassium, chloride and sulphate. The sampling sites are mapped using geographical information systems. GPS (Global positioning system) was employed to locate the coordinates in terms of latitude and longitude. Cation-anion correlation matrixes are plotted using piper plots from values of results obtained through physico-chemical analysis. Experimental results were subjected to statistical analysis using one-way ANOVA. The WQI index in the present study was obtained in the range of 57.6 to 989.1, indicating very poor-quality water in these sampling areas. Results illustrated that groundwater of the study area required treatment before used for consumption.

One of the several significant concerns related to water treatment plants is the transformation of natural organic matter (NOM) concerning quality and quantity due to the changing climatic conditions. The NOM consists of heterogeneous functionalized groups. Phenolic and carboxyl groups are the dominant groups that are pH-dependent and show a stronger affinity towards the metals. Properties of natural organic matter and trace elements govern the binding kinetics, influencing cations' binding to functionalized groups at lower pH. The water treatment process mechanisms like adsorption, coagulation, membrane filtration, and ion exchange efficiencies are sturdily influenced by the presence of NOM with cations and by the natural organic matter alone. The complexation among the natural organic matter and coagulants enhances the removal of NOM from the coagulation processes. The current review illustrates detailed interactions between natural organic matter and the potential impacts of cations on NOM in the water and wastewater treatment facilities.