An innovative design and development of noise barrier with newly composite mix of acoustic panel.

Urban dynamics and anthropogenic interventions led to an increase in noise pollution levels, with relevant implications for worldwide healthcare. Structures created to lessen noise pollution from traffic, industry, or other sources are known as noise, sound, or acoustic barriers. The research paper presents a unique design and development of noise barrier with newly composite mix of acoustic panels and vegetative cover augmenting noise attenuation and aesthetics. The barrier provides a symmetrical design around the vertical axis, hence assures utilization of both faces of the barrier. Additionally, the barrier hosts multiple slots to accommodate multi-material acoustic panels based on diverse noise frequencies and environmental conditions. The barrier integrates movable noise caps at 45°, 90°, 180°, and 270° angles for further attenuation and diversion of noise. A drip irrigation system within the soil box ensures optimal plant growth and stability to barrier. Experimental studies showcase the barrier's performance and its effectiveness in diverse noise scenarios. This innovative development provides a comprehensive solution towards noise mitigation through compact, customizable and sustainable green noise barrier.

A review on generation, characterization, containment, transport and treatment of fecal sludge and septage with resource recovery-oriented sanitation.

Fecal sludge and septage (FSS) are more concentrated than domestic wastewater which makes it difficult to treat and requires immediate attention otherwise, it leads towards serious environmental problems. In this review, an attempt has been made to highlight and discuss the various aspects of fecal sludge and septage management (FSSM) like its generation, characterization, containment, transportation, treatment, reuse and disposal. A comparison of existing fecal sludge treatment plants and technologies has been reviewed considering land requirement, capital cost, operation and maintenance cost, advantages and disadvantages. Based on the existing practices and review, a techno-economic treatment scheme is designed and proposed for solid-liquid separation and treatment of FSS with resource-recovery as fertilizer, material for construction, energy and treated effluent. To make FSSM, self-sustainable, a revenue generation model is also delineated for the researchers and decision-makers to evaluate its feasibility and implementation, especially in developing and underdeveloped countries.

Design and preliminary techno-economic assessment of a pilot scale pharmaceutical wastewater treatment system for ammonia removal and recovery of fertilizer.

Recovery of nutrients from wastewater has a paramount importance for a sustainable and safe environment. In this study removal of ammonia and recovery of resources in the form of struvite from a complex pharmaceutical acidic wastewater having high concentration of ammoniacal nitrogen (NH4-N > 40 g/L) and other co-existing contaminants (magnesium, phosphorous, phenol etc.) was explored. Response Surface Methodology (RSM) was employed for design of experiments and process optimization. RSM results revealed that removal of ammoniacal nitrogen, i.e., struvite precipitation was found to be maximum in alkaline pH (10.5-11.0) at a N:Mg molar ratio (1:0.030 to 1:0.035) and N:P molar ratio (1:0.025 to 1:0.030). X-Ray diffraction, thermo-gravimetric analysis and Fourier transform-infrared spectroscopy confirmed the presence of struvite crystals in the obtained precipitate. Techno-economic assessment (TEA) based on mass energy balance principle and market equipment specifications revealed that a pilot-scale plant set up would have a break-even period of 1.06 years with a return on investment as 94.28%. This clearly elucidated the economic viability of the developed process for industrial applications for management of high ammonia laden pharmaceutical wastewater. While further specific technological improvements are needed for reduction of cost, this study will guide researchers and industries for careful selection of target markets to reduce the cost for successful implementation.

Understanding COVID-19 transmission, health impacts and mitigation: timely social distancing is the key.

COVID-19 is a highly infectious disease caused by SARS-CoV-2, first identified in China and spread globally, resulting into pandemic. Transmission of virus takes place either directly through close contact with infected individual (symptomatic/asymptomatic) or indirectly by touching contaminated surfaces. Virus survives on the surfaces from few hours to days. It enters the human body through nose, eyes or mouth. Other sources of contamination are faeces, blood, food, water, semen etc. Parameters such as temperature/relative humidity also play an important role in transmission. As the disease is evolving, so are the number of cases. Proper planning and restriction are helping in influencing the trajectory of the transmission. Various measures are undertaken to prevent infection such as maintaining hygiene, using facemasks, isolation/quarantine, social/physical distancing, in extreme cases lockdown (restricted movement except essential services) in hot spot areas or throughout the country. Countries that introduced various mitigation measures had experienced control in transmission of COVID-19. Python programming is conducted for change point analysis (CPA) using Bayesian probability approach for understanding the impact of restrictions and mitigation methods in terms of either increase or stagnation in number of COVID-19 cases for eight countries. From analysis it is concluded that countries which acted late in bringing in the social distancing measures are suffering in terms of high number of cases with USA, leading among eight countries analysed. The CPA week in comparison with date of lockdown and first reported case strongly correlates (Pearson's r = - 0.86 to - 0.97) to cases, cases per unit area and cases per unit population, indicating earlier the mitigation strategy, lesser the number of cases. The overall paper will help the decision makers in understanding the possible steps for mitigation, more so in developing countries where the fight against COVID-19 seems to have just begun.

Noise pollution in Mumbai Metropolitan Region (MMR): An emerging environmental threat.

Noise pollution in urban areas is an emerging environmental threat which local agencies and state authorities must consider in planning and development. Excessive noise is becoming a significant problem adversely affecting the physiological and psychological health of the citizens. Present study was carried out to assess and quantitatively evaluate ambient noise levels in Mumbai Metropolitan Region (MMR) consisting of 9 cities namely Bhiwandi-Nizampur, Kalyan-Dombivli, Mira-Bhayandar, Mumbai, Navi Mumbai, Panvel, Thane, Ulhasnagar and Vasai-Virar. The noise environment was assessed on the basis of equivalent continuous sound pressure levels (Leq), day-night noise levels (LDN) and noise limit exceedance factor (NEF) during day and night time of working and non-working days in four different area categories, viz. industrial, commercial, residential and silence zones. Present study shows that silence zones have been the worst affected areas where noise pollution levels and NEF indicate excessive violation of permissible noise limits due to unplanned, congested and unruly spaces for developmental and commercial activities, followed closely by residential and commercial zones. Cities with separate industrial and commercial zones showed less noisy surroundings in comparison with those cities where land use pattern of industrial and commercial zones is around or overlapping each other. It can thus be concluded that appropriate demarcation and planned use of city space is important to avoid exposure to rising noise pollution levels. Based on the noise pollution in (MMR), various control measures are suggested including awareness campaign and strict compliance of the rules and regulations.

Geospatial assessment of tourism impact on land environment of Dehradun, Uttarakhand, India.

India's tourism industry has emerged as a leading industry with a potential to grow further in the next few decades. Dehradun, one of the famous tourist places in India located in the state of Uttarakhand, attracts tourist from all over the country and abroad. The surge in tourist number paved the way for new infrastructure projects like roads, buildings, and hotels, which in turn affects the topography of the mountainous region. In this study, remote sensing and GIS techniques have been used to assess the impact of tourism on the land environment of Dehradun. Satellite images of the years 1972, 2000, and 2016 were analyzed using object-based image analysis (OBIA) to derive land use and land cover (LULC) and ASTER-DEM (Digital Elevation Model) was used to determine the topography of the study area. LULC classification includes built-up, vegetation, forest, scrub, agriculture, plantation, and water body. The slope of the region was categorized as gentle, moderate, strong, extreme, steep, and very steep. To assess the sprawl of built-up on high terrain land, built-up class of LULC was overlaid on slope classes. The overlay analysis reveals that due to increase in tourism, the land use in terms of the built-up area has been extended from gentle slope to very steep slope. The haphazard construction on the extreme, steep, and very steep slope is prone to landslide and other natural disasters. For this, landslide susceptibility maps have also been generated using multicriteria evaluation (MCE) techniques to prevent haphazard construction and to assist in further planning of Dehradun City. This study suggests that a proper developmental plan of the city is essential which follows the principles of optimum use of land and sustainable tourism.

Impact of highway construction on water bodies: a geospatial assessment.

India has witnessed a massive infrastructure boom in the past few years. One of such projects is National Highway-7 (NH-7), a North-South highway connecting Kanyakumari, Tamil Nadu, to Varanasi, Uttar Pradesh, traversing many water bodies. The present study aims to assess the pre- and post-construction impact due to existing, new and widened NH-7 on the physical status of the water bodies, using remote sensing techniques. Satellite images spanning 22 years were procured and analysed for change detection in land use and land cover within the waterbodies. The study indicates that construction activities have led to transformation within the water bodies regarding reduction in area and inter-changing of land use and land cover classes, in turn leading to siltation and reduction of recharge.

Impact of sewage discharges on coastal water quality of Mumbai, India: present and future scenarios.

The simulation study assesses the impact of sewage discharges on the present and predicted water quality of the Mumbai coast using MIKE 21. Water quality parameters in terms of dissolved oxygen (DO), biochemical oxygen demand (BOD) and faecal coliform (FC) are checked against specified standards. The simulation is validated for the present coastal hydrodynamics and observed water quality parameters. The validated model is further used for predicting scenarios in terms of upgradation in a pumping station and improvement in wastewater collection, treatment level and disposal systems. The water quality of the existing coastal environment does not conform to the stipulated standards but improves considerably in the prediction scenarios. However, despite a marked improvement in FC, it is not as per desired standards as no treatment for bacteria removal is considered. The simulation study emphasizes the need for exploring options like the reuse or recycle of treated effluent, as an effort for water conservation.

A multi-temporal analysis for change assessment and estimation of algal bloom in Sambhar Lake, Rajasthan, India.

Sambhar Lake in Rajasthan, India is the major inland salt water lake producing salt for centuries. The present study addresses the monitoring changes in and around the lake and its consequent effect on the lake water ecology. For this, satellite images of the years 1976, 1981, 1997, and 2013 are analyzed for land use land cover classes. Significant reduction in the water body is observed in contrast with the increase in salt pan around the periphery of lake and wetland classes. Further, the extent of water body and algae in the lake are delineated as per normalized difference water index and normalized difference vegetation index. Rainfall data do not indicate any major change in the pattern, but drastic decrease in the extent of water body and significant increase in algal bloom are serious concerns for the lake's existence. This may be due to surrounding anthropogenic activities and construction of check dams and anicuts in the lake catchment which curtail the runoff into the lake and provide favorable growth of algae. Sambhar Lake, being declared as a wetland according to the Ramsar Convention, is necessary to protect and conserve the ecological importance of the lake through sustainable planning and management.

Object-based image analysis for the impact of sewage pollution in Malad Creek, Mumbai, India.

Today, object-based image analysis provides an option for integrating spatial information beyond conventional pixel-based classifications for high-resolution imagery. Due to its rare applicability in pollution assessment, an attempt has been made to assess the spatial extent of sewage pollution in Malad Creek, Mumbai, India. Based on multiresolution segmentation of an IRS P6 (LISS IV) image and the Normalized Difference Turbidity Index (NDTI), the various water quality regions in the creek were classified. The existing literature implies that the reflectance of turbid water is similar to that of bare soil which gives positive NDTI values. In contrast to this, negative values of NDTI are observed in the present study due to the presence of organic matter which absorbs light and imparts turbidity, which is supported by the significant correlation between NDTI and turbidity. A strong relationship is observed between turbidity and water quality parameters, implying the impact of organic matter through discharges of sewage in the creek. Based on the classified regions and the water quality parameters, the extent of pollution was ranked as high, moderate, low and least. The methodology developed in the present study was successfully applied on an IKONOS image for the same study area but a different time frame. The approach will help in impact assessment of sewage pollution and its spatial extent in other water bodies.

Prioritization of catchments based on soil erosion using remote sensing and GIS.

Water and soil are the most essential natural resources for socioeconomic development and sustenance of life. A study of soil and water dynamics at a watershed level facilitates a scientific approach towards their conservation and management. Remote sensing and Geographic Information System are tools that help to plan and manage natural resources on watershed basis. Studies were conducted for the formulation of catchment area treatment plan based on watershed prioritization with soil erosion studies using remote sensing techniques, corroborated with Geographic Information System (GIS), secondary data and ground truth information. Estimation of runoff and sediment yield is necessary in prioritization of catchment for the design of soil conservation structures and for identifying the critical erosion-prone areas of a catchment for implementation of best management plan with limited resources. The Universal Soil Loss Equation, Sediment Yield Determination and silt yield index methods are used for runoff and soil loss estimation for prioritization of the catchments. On the basis of soil erosion classes, the watersheds were grouped into very high, high, moderate and low priorities. High-priority watersheds need immediate attention for soil and water conservation, whereas low-priority watershed having good vegetative cover and low silt yield index may not need immediate attention for such treatments.

Dynamics of sewage outfall plumes based on Landsat-8-derived sea surface salinity and tidal characteristics.

In the face of growing marine pollution, assessment of the sewage outfall discharges is essential as it affects the seawater quality. The study demonstrates sea surface salinity (SSS) variations caused by sewage discharges and links it with tidal characteristics to hypothesize the dynamics of sewage outfall plumes. SSS is estimated using a multilinear regression model based on Landsat-8 (L8) OLI reflectance and in situ SSS data of 2013-2014. Using the validated model, the SSS of the 2018 image is predicted and evidenced by its relationship with colored dissolved organic matter (CDOM). The preliminary results of the hypothesis are encouraging and found that the dispersion patterns of outfall plumes exhibit distinct characteristics depending on the intra-tidal range and hour. The findings indicate a lower SSS in the outfall plume zone than in ambient seawater due to dilution caused by partially treated sewage discharges from diffusers. The plumes observed during the macro tidal range are long and narrowly spread alongshore. In contrast, during the meso and microtidal ranges, the plumes are shorter and are primarily dispersed offshore rather than alongshore. During slack times, low salinity levels are visibly concentrated around outfalls as there is no water movement to disperse the accumulated sewage discharges from diffusers. These observations suggest that slack periods and low-tidal conditions could be significant factors contributing to the accumulation of pollutants in coastal waters. The study further suggests more datasets such as wind speed, wind direction, and density variations are needed to understand the processes influencing the outfall plume dynamics and variation in SSS. The study recommends increasing the treatment capabilities of existing treatment facilities from primary to tertiary treatment levels. Furthermore, it is important to warn and educate the public about the health risks associated with exposure to partially treated sewage that is discharged from outfalls.

Evaluation of noise barriers based on geometries and materials: a review.

The acoustical properties of a barrier are highly dependent on the physical properties of the material and the internal structure of the material. The acoustical material can curtail the quality of sound or enhance the dispersion, depending on the application being considered. The efficient acoustic performance of noise barriers possessing different shapes and materials including waste materials is reviewed for field implementation to achieve the low-cost sustainable noise barrier application in the Indian context. The review analysis of research papers demonstrates that the acoustic performance of barriers is dependent on different shapes, materials, and textures as well as onsite geometry. Based on the review study, T-shaped barriers with a soft top surface are found to be efficient at noise attenuation. For transparent barriers, perceived loudness and noise annoyance are assessed lower than that for opaque barriers and utilization of waste materials viz. plastic, rubber, bottom coal ash, etc. gives high noise attenuation along with low-cost efficiency. Noise pollution levels are high from prescribed noise limits in most of the Indian metropolitan cities. The Indian government is working on mitigation strategies of noise pollution as well as abiding laws regarding noise standards for the zone (residential, industrial, commercial, and silences) wise. In contrast, some communities which are adjacent to roads are suffering from high noise levels in the ambience. Therefore, it requires a coherent strategy for long-term measures intended at minimizing exposure of noise hence providing much more comfort to live, work, and shop near high-traffic roads. Noise barriers are highly beneficial in mitigating the emitted noise from the traffic.

Statistical assessment of seafront and beach water quality of Mumbai, India.

The water quality of seafronts and beaches of Mumbai is under pressure and deteriorating due to discharge of partially treated sewage and wastewater through point and nonpoint sources. The objective of the study was to assess the water quality and to correlate physico-chemical and bacteriological parameters for establishing relationship, association and dependence on each other. The water quality parameters were selected as per SW II standards specified by Central Pollution Control Board, India and nutrient parameters as strong indicators of sewage pollution. Box and whisker plots were generated for evaluating spatio temporal variation of water quality which suggest influence of organic pollution mostly at Mahim and Dadar in the form of outliers and extremes. Pearson's correlations were estimated between parameters and found significant correlation with each other indicating influence of sewage on water quality. The water quality of beaches and seafronts were found unsafe for recreational purposes. The study suggested that designated water quality can be achieved by restricting nonpoint source through improvement in wastewater collection systems, appropriate level of treatment and proper disposal.

Assessment of water quality using cluster analysis in coastal region of Mumbai, India.

The coastal water quality of Mumbai is deteriorating due to various point and non-point wastewater sources. Hence, it is desirable to monitor coastal water quality for various water-related activities like bathing, contact water sports, recreation, and commercial fishing. The objective of this paper is to assess the seasonal water quality on the basis of seawater standards. Based on water-quality analysis of 17 seafronts and beaches, most of the parameters were exceeding the standards. The statistical cluster analysis was carried out for evaluating impact of wastewater and sewage discharges. The hierarchical cluster analysis resulted into three clustered groups, namely less polluted, moderately polluted, and highly polluted sites with similar characteristics of water quality. Mahim was found to be worst-affected beach due to incoming organic load from the Mithi river in comparison to other seafronts and beaches. Unaccounted sources of sewage and wastewater should be identified and rerouted through sewerage system by improving collection efficiency, treatment, and proper disposal for achieving designated receiving water quality standards.

Assessment of groundwater quality in Puri City, India: an impact of anthropogenic activities.

Puri City is situated on the east coast of India and receives water supply only from the groundwater sources demarcated as water fields. The objective of this paper is to assess and evaluate the groundwater quality due to impact of anthropogenic activities in the city. Groundwater samples were collected from the water fields, hand pumps, open wells, and open water bodies during post-monsoon 2006 and summer 2007. Groundwater quality was evaluated with drinking water standards as prescribed by Bureau of Indian Standards and Environmental Protection Agency to assess the suitability. The study indicated seasonal variation of water-quality parameters within the water fields and city area. Groundwater in the water fields was found to be suitable for drinking after disinfection. While in city area, groundwater quality was impacted by onsite sanitary conditions. The study revealed that groundwater quality was deteriorated due to the discharge of effluent from septic tanks, soak pits, pit latrines, discharges of domestic wastewater in leaky drains, and leachate from solid waste dumpsite. Based on observed groundwater quality, various mitigation measures were suggested to protect the water fields and further groundwater contamination in the city.

A critical and intensive review on assessment of water quality parameters through geospatial techniques.

Evaluation of water quality is a priority work nowadays. In order to monitor and map, the water quality for a wide range on different scales (spatial, temporal), the geospatial technique has the potential to minimize the field and laboratory work. The review has emphasized the advance of remote sensing for the effectiveness of spectral analysis, bio-optical estimation, empirical method, and application of machine learning for water quality assessment. The water quality parameters (turbidity, suspended particles, chlorophyll, etc.) and their retrieval techniques are described in a scientific manner. Available satellite, bands, resolution, and spectrum ranges for specific parameters are critically described in this review with challenges in remote sensing for water quality analysis, considering non-optical active parameters. The application of statistical programmes like linear (multiple regression analysis) and non-linear approaches is discussed for better assessment of water quality. Emphasis is given on comparison between different models to increase the accuracy level of remote sensing of water quality assessment. A direction is suggested for future development in the field of estimation of water pollution assessment through geospatial techniques.

Hydrodynamic assessment of sewage impact on water quality of Malad Creek, Mumbai, India.

The rapid population growth and uncontrolled development in the coastal zone have led to major pollution impacts on creeks, estuarine, and coastal environment. Water quality models are valuable tools to understand the environmental processes for prediction of pollution impacts and evaluate future trends for management. Presently, the Malad creek in west coast of Mumbai receives wastewater and sewage from open drains and partially treated sewage from Malad and Versova treatment plants. The objective of the paper is to assess the environmental quality and estimate the extent of improvement in different parts of the creek by enhancing the collection efficiency and adequate treatment of sewage as well as disposal through ocean outfall. A hydrodynamic and water quality simulation has been carried out for the present condition in the creek and calibrated and validated with two different season data for better representation of the system. Calibrated model has been used to generate future scenarios based on various options. Among scenarios, option of treated effluent diverted to propose outfall and improvement in collection of unorganized flow through sewage up to 40% and 60% are found most significant for biochemical oxygen demand reduction and increase in dissolved oxygen. Fecal coliform reduction is also found drastically but still very high against standard. To improve the environmental quality of the creek, still upper stretch requires more dilution and flushing due to narrow width and contribution of heavy pollution from open drains.

Traffic noise prediction model of an Indian road: an increased scenario of vehicles and honking.

Noise is considered as an underrated and underemphasized pollutant in contrast to other pollutants of the environment. Due to the non-acute response of health effects, people are not vigilant towards consequences regarding noise pollution. The expansion of the transportation industry is contributing towards the increment in the public and private vehicular volume which causes an increment in noise pollution. For evaluation of respective scenario, the research study has been conducted on one of the minor roads of Nagpur, India; for 2 years, viz., 2012 and 2019. The study concludes an increment of 5-6 dB(A) in noise level, 4-6 times in honking, and 1.7 times in traffic volume. The study confirms increment in sound pressure by 65.9% and 81.9% for the year 2012 and 2019 during morning and evening sessions, respectively. Noise prediction model has also been developed for the abovementioned years, using multiple regression analysis, considering traffic volume, honking, and speed against noise equivalent level. Honking has been further characterized into honk by light and medium category vehicles as acoustical properties of horns vary with respect to category of vehicle and introduced into the noise prediction model. Noise prediction model for 2019 has predicted the noise level in a range of - 1.7 to + 1.4 dB (Leq) with 84% of observations in the range of - 1 to + 1 dB (Leq), when compared with observed Leq on the field. For proper management of noise pollution, a noise prediction model is essentially needed so that the noise level can be anticipated, and accordingly, measures can be outlined and executed. This increased noise level has serious impacts on human hearing capacity and overall health. Accordingly, noise mitigation preventive measures are recommended to control traffic noise in the urban environment.

An innovative approach of urban noise monitoring using cycle in Nagpur, India.

Noise is one of the most significant sources of environmental pollution in metro cities. Traffic noise plays an important role to contribute to ambient noise pollution. Noise pollution monitoring was carried out using sound level meter mounted on the cycle with the help of mould fixed on it. Cycle is a noiseless mode of transport and therefore, it was used for noise monitoring over 700 locations in Nagpur City. Noise levels were recorded at each location for 5 min during peak rush hours of traffic in the morning and in the evening at an interval of 1 s leading to around 300 readings each. Noise indices like Leq, L90, L10, Lmax and Lmin were calculated for noise level data analysis. TNI was also determined for analysis of traffic noise on intersections of roads. Equivalent noise levels were transferred into the Geographic Information System (GIS) and spatial analysis tool was used to create spatial and strategic noise maps. Based on the maps, it is revealed that noise levels are exceeded all over the city with respect to ambient noise standards. It was experienced that intersections of roads during peak rush time are very noisy due to honking. The study recommends the noise monitoring through cycle-mounted sound level meter since it covers unapproachable sites, more coverage in the city that helps in identifying hotspot area of concern for noise abatement strategies and planning.