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In the rapidly urbanizing country like India, the transportation sector is growing rapidly, which lead to overcrowded roads producing air and noise pollution. Noise of a particular region is influenced by the volume of traffic on the highway, in addition to other causative factors like existing infrastructure and industrial setup etc. In the present paper, a geographical information system (GIS)-based noise simulation model has been developed to generate noise levels in Versova region of Mumbai, India. The study area comprises effect of infrastructure, road network, traffic volume, and various mechanical components like sewage pumping station and wastewater treatment facility. Various meteorological parameters and effect of land use and land cover on noise attenuation are also considered in the model. In this way, commutative noise prediction for point as well as mobile sources has been presented in the study. GIS-based noise simulation has been calibrated with observed noise levels during day and night time with correlation of 0.84 and 0.74, respectively.

Most critical flood problems occur in urban areas where values at risk are higher and damages tend to be heavier. In the present study, a hydrodynamic simulation of the river Yamuna has been generated under different designated flood flows to delineate the land availability under existing and modified riverbed geometry including channel dredging and riverbed dressing. Flood flows for various return periods, namely once in 10, 25, 50, and 100 years are estimated based on the past 41 years of recorded data using flood frequency analysis. The model set up considered the river stretch of 23 km from the Wazirabad barrage upstream to the Okhla barrage downstream, which includes manmade structures like bridges and barrages. Model calibration is achieved by comparing the water surface elevations with observed data at various downstream gauge stations. The land availability based on submergence scenarios under existing riverbed condition is estimated to be 1147.6, 873.1, and 762.6 ha, respectively, for 10, 50, and 100 year return flood. Various simulations are generated including channel dredging and riverbed dressing to obtain safe height and safe width for dressing the riverbed. The modified river geometry considered channel dredging in 750 to 1350 m width, and riverbed dressing for safe height and width in three levels in various sections. The land availability under this scenario is estimated to be 2197, 1129, and 545 ha for 10, 50, and 100 year return flood, respectively. It is proposed to dress the riverbed by utilizing the material obtained from channel dredging in three levels to maintain the transverse and longitudinal slope, river morphology, and river system. Developmental planning in the riverbed may include utilization of land at three levels for various purposes such as playgrounds, nursery, etc. However, it is suggested that the feasibility study of the project requires detailed engineering including slope stability prior to implementation of the riverbed development.

Monitoring for seasonal variation and changes in groundwater is a costly project. Assessing groundwater at selected monitoring sites and for site-specific indicators may reduce the cost of subsequent monitoring. In this context, the present study developed a method to assess groundwater using a combination of multivariate and univariate statistical techniques to identify critical sites of contamination. The sample data used describes the groundwater quality in Allahabad, India. The factor analysis brings out the observable parameters for groundwater pollution. Finally, univariate techniques such as analysis of variance (ANOVA) and Bonferroni t-test identify the critical sites of groundwater pollution. The first factor indicated high loading (>0.6) of total dissolved solids, Cl, Na, Mg, conductivity, SO 4 , and hardness. This represented overall pollution status of groundwater from human habitation, waste disposal, and agricultural activities in Allahabad. Iron, Mn, and Zn showed loading on distinct factors and indicated local contamination. Univariate techniques ANOVA and Bonferroni t-test for Zn concentration in handpump samples revealed heavy metal contamination at Hasimpur and Beniganj in India. Thus, initial monitoring followed by statistical analysis can help identify critical sampling locations and important indicators.

Water quality standards are developed world over by National and International agencies for pollution control decision-making. Use-based water quality classification criteria and Water Quality Indices (WQIs) also play important role in assessment of water resources for their suitability with reference various uses. Formulation of value function curves and weights assigned to parameters in WQIs are often defined by local water experts and hence WQIs are known to inherit subjectivity. Assignment of weights a priori to various water quality parameters results in misclassification of water quality by WQI. A method of dynamic weighting has been developed in the present work to assign weights to water quality parameters with due consideration to their pollution effect at a particular site. Application of a methodology to Overall Index of Pollution (OIP) provides water quality classification of Indian rivers as “Polluted”, “Acceptable”, and “Slightly Polluted”, which is comparable with the reported CPCB classification as well as with the statistical index CCME-WQI. The methodology developed is general and can be applied to any subjective index. This is exemplified by dynamically weighting the parameters in NSF-WQI for Red and Waikato rivers. Dynamic weighting system provides a true representation to comprehend water quality classification and to achieve River Quality Objectives.

Solid waste management systems currently receive wide attention, from both economic and environmental planners, because of their complexity during coordination of various management strategies. The efficiency and cost effectiveness of route optimization and disposal site selection depend largely upon the appropriate placement of storage bins and their corresponding command area for waste contribution. The present paper illustrates a geographic information system (GIS) based algorithm for optimal location and number of storage bins, considering p-median constrained model, based on Indian guidelines for Municipal Solid Waste Rules. The algorithm also computes the contributing command area of solid waste to a particular bin, based on the shortest distance, with descending slope for ease in solid waste collection.

A methodology based on genetic algorithm has been developed for lower cost design of new, and augmentation of existing water distribution networks. The results have been compared with those of non-linear programming technique through application to several case studies. The genetic algorithm results in a lower cost solution. Parameters governing the convergence of the solutions in non-linear and genetic algorithms are also discussed.

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 sewerage 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.

A well known river hydrodynamic model RiverCAD has been used to simulate and visualize flood scenarios for different designated flood flows under complex riverbed geometry with several man made structures like bridges and barrages. The model applied successfully for the stretch of 23 km in the Yamuna floodplain of Delhi region from Wazirabad barrage in the upstream to Okhla barrage. Flood flows for various return periods namely once in 10, 25, 50 and 100 years were estimated based on recorded flow data for the period of 1963 to 2003 using standard flood frequency analysis techniques. The simulation results were compared and the model was calibrated with water surface elevation records of the previous floods at various barrage and bridge locations. Simulation results enabled prediction of maximum water levels, submergence scenarios and land availability under different designated flood flows for riverbed assessment, development and management.