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Sargaonkar A 《Environmental monitoring and assessment》2006,117(1-3):491-503
Non-point source (NPS) pollution is the result of various land use practices such as agriculture, sites of construction and
waste disposal, urban development and so on. The control of NPS pollution is possible by regular monitoring and assessment
on watershed basis to educate people for implementing well-known structural and non-structural measures. Recent trend is to
use GIS based modelling tool for assessment of rainfall-runoff and non-point loading. The approach requires generation and
analysis of basin wide data on various features of land and estimates of Event Mean Concentrations (EMCs) of pollutants in
the runoff. In the present paper, basin wide data in different districts of Tapi basin has been analysed for land use distribution;
fertilizer application; low, medium and high-density habitation; and annual rainfall. Coefficients of runoff have been estimated
considering pervious and impervious area for different land use types, and compared with the reported values for Indian conditions.
The estimated mean annual runoff flow indicated that two districts Jalgaon and Dhule contribute maximum runoff to the Tapi
River. Estimates of EMCs for BOD and nutrients (N and P) in the runoff from various districts are useful in GIS-based modelling
study for NPS pollution assessment. 相似文献
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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. 相似文献
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Various National and International Agencies involved in water quality assessment and pollution control have defined water quality criteria for different uses of water considering different indicator parameters. Classification schemes for water quality criteria/standards developed by these agencies differ inaddition to terminologies used such as Action level, Guide level etc. in defining the concentration values in these classes. In the present article a general classification scheme viz. Excellent,Acceptable, Slightly Polluted, Polluted and Heavily Polluted water is proposed for surface water quality assessment. The concentration ranges in these classes are defined in Indianscenario considering Indian Standards and CPCB criteria. Standardsby the European Community (EC), WHO etc. and the reported factsabout the pollution effects of important water quality indicatorparameters on the surrounding were also taken into account. Themathematical equations to transform the actual concentrationvalues into pollution indices are formulated and correspondingvalue function curves are plotted. Based on the individual indexvalues, an `Overall Index of Pollution' (OIP) is estimated. Theapplication of OIP is demonstrated at a few sampling stations onriver Yamuna based on observed water quality data. The general classification scheme along with concentrationranges defined in these classes will be of immense use fordetermining the surface water quality status with reference tospecific individual parameter, and the OIP for assessing theoverall water quality status in Indian context. 相似文献
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Anisha Nijhawan Priyanka Jain Aabha Sargaonkar Pawan Kumar Labhasetwar 《Environmental monitoring and assessment》2014,186(9):5547-5560
A water safety plan for the city of Nagpur was developed by the National Environmental Engineering Research Institute (NEERI) and Nagpur Municipal Corporation (NMC). Possible hazards were identified through field visits. Based on this, an improvement plan was drawn up to suggest corrective actions and a time frame for implementation. The findings of this study are being used to modify or repair components of the water supply system and upgrade management procedures. This paper highlights the lessons learnt during implementation of the WSP and the key challenges faced. 相似文献
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