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Groundwater is the most important and valuable natural resources especially in coastal urban environment where surface water is insufficient to satisfy the water requirement. Puri city is located on the east coast of India where groundwater is the only source available to meet city water supply. As the city is situated on the sandy aquifer, quality of groundwater is deteriorating because of anthropogenic activities, lack of sewerage system, etc. The objective of the study was to assess the groundwater fluctuation during post-monsoon and summer with respect to hydrogeological conditions, topography, and groundwater consumption pattern of the city. For this assessment and analysis, Geographic Information System (GIS) was used to visualize topography of the area through digital elevation model (DEM) and distribution of groundwater contours spatially and temporally. The probable areas prone to contamination were identified based on aquifer property and depths to water table below ground. Copyright © 2010 John Wiley & Sons, Ltd.

In recent years, contamination of water in water distribution systems (WDS) has been recognized as a major cause of waterborne diseases. Owing to old and deteriorated pipes, and the presence of pollution sources in contact with the supply line, water boards often decide to replace the network in the interests of public health. This being a cost-intensive and time-consuming programme, decision makers need a basis for phase-wise investment planning. In view of this, Integrated Risk Assessment of Water Distribution System (IRA-WDS) for the supply network of Adikmet Subzone-I in Hyderabad, India, was undertaken. GIS maps were prepared for the water supply network, sewer network, open drains, soil and groundwater table at 1:2,200 scale and ‘pipe condition assessment’ and identification of ‘contaminant ingress’ locations were performed using IRA-WDS. Findings indicated 18 pipes in ‘very bad’ and ‘bad’ condition in the entire network. ‘High risk’ of contamination was exhibited in 20 locations, suggesting the need for rehabilitation of only 2 to 3% of pipes in the initial phase.

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.

Groundwater recharge and mounding of water-table is a complex phenomenon involving time- and space-dependent hydrologic processes. The effect of long-term groundwater mounding in the aquifer depends on soil, aquifer geometry and the area contributing to recharge. In this paper, a GIS-based spatio-temporal algorithm has been developed for the groundwater mound dynamics to estimate the potential rise in the water-table and groundwater volume balance residual in an unconfined aquifer. The recharge and mound dynamics as predicted using the methodology recommended here were compared with those using the Hantush equation, and the differences were quite significant. The significance of the study is to assess the effectiveness of the basin in terms of its hydrologic and hydraulic properties for sustainable management of groundwater recharge. Copyright © 2007 John Wiley & Sons, Ltd.

The Tapi is a major interstate, westerly flowing river with 14 tributaries, of which the left bank tributaries support large settlements in Maharashtra State. It has been identified as one of the water scarce basins of India. There are many dams and barrages in the basin to store and divert water for agricultural and industrial purposes. This results in low flow and deterioration of water quality in the region particularly in non‐monsoon months. This paper presents the details of a GIS‐based rainfall‐runoff modelling study carried out to assess the runoff flow in the sub‐catchments and at the outlet of the Tapi Basin. Using mean monthly rainfall data at seven gauging stations in the basin, and land use and soil characteristics as reported by the Central Pollution Control Board (CPCB), the annual runoff flow at the watershed outlet was estimated to be 18,814 MCM. A comparison of runoff generated in the sub‐catchments and the observed runoff at Central Water Commission (CWC) monitoring stations is presented...

This study presents a geographical information system (GIS)-based procedure for the precise estimation of solid waste generation, computed using the local population density and income group distribution. Using a triangulated irregular network (TIN) in a GIS environment, the procedure further determines the command area for waste allocation to a particular bin which is generally located so the route slopes towards the collection points for ease of transportation by cart pullers. Computational results of bin location, type, size and the frequency of removal are presented for a typical urban area with known population density, income group distribution, road network and topology.

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.

An optimization algorithm with recourse to a nonlinear programming technique based on the interior penalty function with Davidon-Fletcher-Powell method, incorporating the graph theoretic approach for analysis of networks, has been developed for design of functional and least-cost water distribution systems with multiple reservoirs. The model has the capability to design a new system as well as to reorganize an existing system. Reorganization of a system becomes necessary due to increased water demand resulting from an increase in population density and enhanced service levels or expansion to the new areas. Further, the hydraulic simulator based on graph theory enables design of all types of systems; viz branched, looped or a combination thereof including nodes with specified fixed energy grades. The software package has been developed for use on an IBM-PC compatible microcomputer. The efficacy of the algorithm has been demonstrated through an example on design of a typical water distribution system.

Groundwater quality data on physico-chemical, bacteriological and heavy metal concentrations in three cities (Faridabad, Allahabad and Varanasi) in Ganga-Yamuna basin was subjected to multivariate analysis (MVA) using SPSS. The factors extracted showed high loading (0.3) of various parameters, such as Cl, conductivity, TDS, hardness, Na, Mg, and SO4, indicating contamination due to leaching of pollutants. Major manifest variable associated with these factors is the unorganized solid waste dumping practiced in all the cities. Bacterial contamination of hand pump samples in Allahabad is attributed to surface water-groundwater interaction. The factor with high loading of Ca and F is indicative of geological conditions of the region. Wells in Yamuna river sub-watershed exhibit less freshwater recharge, which is attributed to surface water pollution and sediment deposition in the river. Thus, the methodology for hydrogeological analysis is useful to identify critical water quality issues and possible sources of pollution in river basins.

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 GIS based algorithm has been developed to estimate the rainfall-runoff relationship of Sathanur reservoir catchment based on Soil Conservation Service (SCS) model. The landuse and soil maps were prepared in Arc/Info 9.0 and an arc macro language (AML) programme was developed to assign curve number based on landuse and soil classification including hydrological condition of the area. The algorithm was executed successfully by rainfall data for computation of runoff depth in all the sub watersheds. The study is important for a watershed, which does not have runoff records and can be used for planning of various water conservation measures.

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.

Water supply in old Jammu city is not evenly distributed due to undulating terrain and increase in population density. A study was undertaken to suggest measures for improvement to the distribution system. The paper presents results of analysis carried out using computer package OPT DIS developed at NEERI for optimal design of distribution sytem including system augmentation and reorganization measures needed for the design year 2021. The analysis of zone 1 of the distribution network indicates that seven pipes need alteation to cater to the demand for the year 2006 and fifteen pipes need replacement for the year 2021. New pipelines (13 nos.) are to be provided in parallel to the existing pipes in Upper Reach and 28 pipes in Lower Reach to ensure the service standards of 225 lpcd with minimum residual head of 17 m. Efficient algorithm for augmentations of water supply systems comprising combination of dead-end and loop network are having much wider application in developing countries. The software OPT DIS developed at NEERI was found to be extremely powerful and user friendly for addressing such systems with varying demand pattern, peaking factor, pipe condition, water supply modes and design horizones.