ABSTRACT The Soil Conservation Service curve number (SCS-CN) method is a well-recognized techniqu... more ABSTRACT The Soil Conservation Service curve number (SCS-CN) method is a well-recognized technique for the estimation of direct surface runoff from a rainfall event. Most of the recently developed SCS-CN-based models including the original one ignore the effect of storm duration or rainfall intensity on surface runoff, an important aspect of the rainfall-runoff model. Some of these models have, however, included the antecedent moisture conditions. In this study, storm duration is incorporated in a recently modified version of the SCS-CN method to derive a more advanced model. This version is found to perform generally better than the other on the data of 60 small U. S. watersheds. The former model performed significantly better than the latter on the watersheds dominated by silty soils and cultivated land uses. DOI: 10.1061/(ASCE)HE.1943-5584.0000443. (C) 2012 American Society of Civil Engineers.
International Journal of Ecology & Development, 2008
The coastal water bodies such as creeks and estuaries are continuously subjected to the natural a... more The coastal water bodies such as creeks and estuaries are continuously subjected to the natural and man induced perturbations. Hydrodynamics is the unique feature of these water bodies and required to be predicted for various design purposes. Numerical modeling is often preferred in such cases over the analytical solutions and physical models because of its greater flexibility. In the present paper, a two-dimensional depth averaged fully implicit finite element model has been used to study the hydrodynamics of Dahanu Creek and Cochin estuary located at the western coast of India. The model has been found to predict the hydrodynamics satisfactorily.
This study investigates the turbulent flow properties experimentally in the vicinity of two side-... more This study investigates the turbulent flow properties experimentally in the vicinity of two side-by-side circular cylinders, along with the influence of the third cylinder of the same dimension placed in the upstream and successively in the downstream forming an equilateral triangle. Three-dimensional stereoscopic Particle Image Velocimetry (PIV) was employed to collect the instantaneous velocity data around the arrangements. The study highlights the prime parameters of turbulence such as the mean velocities, Reynolds stresses, turbulent kinetic energy (TKE), quadrant analysis and Q-criteria for vortices, which are responsible for the development of various problems such as scour-hole around the cylindrical pier arrangements, disturbance around industrial and marine structures. The spectral analysis was performed to examine the energy distributions, vortex-shedding frequencies with corresponding Strouhal numbers. Dominant vorticity locations were identified from the contours of Q-cr...
An integrated distributed watershed model with channel network for rainfall—runoff simulation is ... more An integrated distributed watershed model with channel network for rainfall—runoff simulation is presented. Interception is estimated by an exponential model based on leaf area index (LAI). The Green-Ampt Mein Larson (GAML) model is used for the estimation of infiltration in the watershed. For runoff estimation, diffusion wave equations are solved using the finite element method (FEM), together with application of the channel network concept. Interflow is simulated using the FEM-based model. A geographic information system (GIS) was used to prepare the input data required for the distributed model. The developed channel network based distributed model was applied to Peacheater Creek watershed, USA. The model performed well on some validation events, but not on all of them. The problems may be due to topographic complexities, or to differences in the characteristics between the calibration storms and those in the validation data set. The developed model has to be further verified for watersheds at different geographic locations for better validation.
International Journal of River Basin Management, 2011
I am delighted to be able to announce the award of the very first International Journal of River ... more I am delighted to be able to announce the award of the very first International Journal of River Basin Management annual best paper prize to Professor Alon Tal of Ben Gurion University and his co-workers for their study entitled ‘Chemical and biological monitoring in ephemeral and intermittent streams: a study of two transboundary Palestinian-Israeli watersheds’ (DOI: 10.1080/15715124.2010.491796). Amongst the many excellent papers published by JRBM in 2010, the work by Tal et al. stood out as a clear embodiment of the science that JRBM seeks to promote. In their paper, Tal and colleagues from Institutions on both sides of the Israeli-Palestinian divide came together in a spirit of co-operation to address a pressing regional environmental issue. More importantly perhaps for the wider field of river basin management, the paper demonstrates that high quality, rigorous science is essential in order to allow the adoption of evidence-based policy and decision-making. Despite the large number of journal papers now published on river basin management every year, very few connect science and management in the fundamental way that has been achieved here. When one also considers the transboundary nature of the problem studied by Tal and his colleagues and the highly complex local political context, it becomes clear what a singular achievement this work represents. In the paper, Tal et al. present research supported by a grant from the Middle East Research and Cooperation Program funded by USAID (http://www.usaid.gov/our_work/merc/ program_description.html) in which they undertook a comprehensive evaluation of environmental conditions in two ephemeral transboundary streams which originate in Palestinian land and flow into Israel. The streams are representative of numerous watersheds in the region and exhibit high concentrations of point and non-point sources of pollution. Many of the region’s streams that in the past had no flow except during isolated storm have emerged as perennial streams, channelling raw or partially treated industrial or municipal wastes. Management of these natural resources constitutes a unique challenge, but the findings of Tal et al. suggest important ways forward for future restoration strategies. This is superb work, and I would like to congratulate Professor Tal and his colleagues for setting such a high standard for the inaugural 2010 JRBM best paper prize. I hope this work will inspire other authors and I look forward to publishing further excellent papers in 2011.
Proceedings of the International Conference on Cloud-Assisted Services – CLASS 2015, Ljubljana, S... more Proceedings of the International Conference on Cloud-Assisted Services – CLASS 2015, Ljubljana, Slovenia, 5-6 November 2015 – Ljubljana: Fakulteta za gradbeništvo in geodezijo, Komisija za informatiko, knjižničarstvo in založništvo, 2015.
<p>Droughts are the major natural disasters affecting water availability le... more <p>Droughts are the major natural disasters affecting water availability leading to social, economic, and environmental challenges. Due to climate variability, investigation of climate change impact on droughts is of vital importance for sustainable societal and ecosystem functioning.  Western Ghats, a humid tropical region of India is selected as a case study to investigate the change in drought characteristics subjected to future climate change. In the last few decades, due to monsoon failure, the intensity of droughts has been identified to increase in this region making this study important. For future climatic variables, the ensemble of five Global Climate Models (GCMs) in the Coupled Model Intercomparison Project (CMIP5) are considered for the Representative Concentration Pathways (RCPs) 4.5 and 8.5. Standardized Precipitation-Evapotranspiration Index (SPEI) for the 12-month accumulated period is considered to assess the change in the drought characteristics during near (2011–2040), mid (2041–2070), and far future (2071–2100). The results indicate an increase in drought events in the future with maximum change during the far future for both RCP 4.5 and 8.5 scenarios. The major areas affected are in the southern part of Kerala and Karnataka. The change in total severity and duration of these drought events are high during the near future, moderate during the mid-future, and very high during the far future in both scenarios with RCP 8.5 being more severe. The findings show the variability in drought characteristics both spatially and temporally across the study area. The results will be helpful in identifying the hotspots prone to drought risk. This will serve as important guidance in improving the identification of causes, minimizing impacts, and enhancing the resilience to droughts in the study area. Further, the important implication of the study will be for water resource planning and management to strategize policies that emphasize on providing water in water-scarce regions during extreme drought situations.</p>
In this paper, a rainfall runoff model for coastal urban watershed con-sidering the effects of ti... more In this paper, a rainfall runoff model for coastal urban watershed con-sidering the effects of tidal variations using Finite Element Method (FEM) is presented. Overland flow is modeled using the mass balance equation considering the impervious character of the urban ...
ABSTRACT The Soil Conservation Service curve number (SCS-CN) method is a well-recognized techniqu... more ABSTRACT The Soil Conservation Service curve number (SCS-CN) method is a well-recognized technique for the estimation of direct surface runoff from a rainfall event. Most of the recently developed SCS-CN-based models including the original one ignore the effect of storm duration or rainfall intensity on surface runoff, an important aspect of the rainfall-runoff model. Some of these models have, however, included the antecedent moisture conditions. In this study, storm duration is incorporated in a recently modified version of the SCS-CN method to derive a more advanced model. This version is found to perform generally better than the other on the data of 60 small U. S. watersheds. The former model performed significantly better than the latter on the watersheds dominated by silty soils and cultivated land uses. DOI: 10.1061/(ASCE)HE.1943-5584.0000443. (C) 2012 American Society of Civil Engineers.
International Journal of Ecology & Development, 2008
The coastal water bodies such as creeks and estuaries are continuously subjected to the natural a... more The coastal water bodies such as creeks and estuaries are continuously subjected to the natural and man induced perturbations. Hydrodynamics is the unique feature of these water bodies and required to be predicted for various design purposes. Numerical modeling is often preferred in such cases over the analytical solutions and physical models because of its greater flexibility. In the present paper, a two-dimensional depth averaged fully implicit finite element model has been used to study the hydrodynamics of Dahanu Creek and Cochin estuary located at the western coast of India. The model has been found to predict the hydrodynamics satisfactorily.
This study investigates the turbulent flow properties experimentally in the vicinity of two side-... more This study investigates the turbulent flow properties experimentally in the vicinity of two side-by-side circular cylinders, along with the influence of the third cylinder of the same dimension placed in the upstream and successively in the downstream forming an equilateral triangle. Three-dimensional stereoscopic Particle Image Velocimetry (PIV) was employed to collect the instantaneous velocity data around the arrangements. The study highlights the prime parameters of turbulence such as the mean velocities, Reynolds stresses, turbulent kinetic energy (TKE), quadrant analysis and Q-criteria for vortices, which are responsible for the development of various problems such as scour-hole around the cylindrical pier arrangements, disturbance around industrial and marine structures. The spectral analysis was performed to examine the energy distributions, vortex-shedding frequencies with corresponding Strouhal numbers. Dominant vorticity locations were identified from the contours of Q-cr...
An integrated distributed watershed model with channel network for rainfall—runoff simulation is ... more An integrated distributed watershed model with channel network for rainfall—runoff simulation is presented. Interception is estimated by an exponential model based on leaf area index (LAI). The Green-Ampt Mein Larson (GAML) model is used for the estimation of infiltration in the watershed. For runoff estimation, diffusion wave equations are solved using the finite element method (FEM), together with application of the channel network concept. Interflow is simulated using the FEM-based model. A geographic information system (GIS) was used to prepare the input data required for the distributed model. The developed channel network based distributed model was applied to Peacheater Creek watershed, USA. The model performed well on some validation events, but not on all of them. The problems may be due to topographic complexities, or to differences in the characteristics between the calibration storms and those in the validation data set. The developed model has to be further verified for watersheds at different geographic locations for better validation.
International Journal of River Basin Management, 2011
I am delighted to be able to announce the award of the very first International Journal of River ... more I am delighted to be able to announce the award of the very first International Journal of River Basin Management annual best paper prize to Professor Alon Tal of Ben Gurion University and his co-workers for their study entitled ‘Chemical and biological monitoring in ephemeral and intermittent streams: a study of two transboundary Palestinian-Israeli watersheds’ (DOI: 10.1080/15715124.2010.491796). Amongst the many excellent papers published by JRBM in 2010, the work by Tal et al. stood out as a clear embodiment of the science that JRBM seeks to promote. In their paper, Tal and colleagues from Institutions on both sides of the Israeli-Palestinian divide came together in a spirit of co-operation to address a pressing regional environmental issue. More importantly perhaps for the wider field of river basin management, the paper demonstrates that high quality, rigorous science is essential in order to allow the adoption of evidence-based policy and decision-making. Despite the large number of journal papers now published on river basin management every year, very few connect science and management in the fundamental way that has been achieved here. When one also considers the transboundary nature of the problem studied by Tal and his colleagues and the highly complex local political context, it becomes clear what a singular achievement this work represents. In the paper, Tal et al. present research supported by a grant from the Middle East Research and Cooperation Program funded by USAID (http://www.usaid.gov/our_work/merc/ program_description.html) in which they undertook a comprehensive evaluation of environmental conditions in two ephemeral transboundary streams which originate in Palestinian land and flow into Israel. The streams are representative of numerous watersheds in the region and exhibit high concentrations of point and non-point sources of pollution. Many of the region’s streams that in the past had no flow except during isolated storm have emerged as perennial streams, channelling raw or partially treated industrial or municipal wastes. Management of these natural resources constitutes a unique challenge, but the findings of Tal et al. suggest important ways forward for future restoration strategies. This is superb work, and I would like to congratulate Professor Tal and his colleagues for setting such a high standard for the inaugural 2010 JRBM best paper prize. I hope this work will inspire other authors and I look forward to publishing further excellent papers in 2011.
Proceedings of the International Conference on Cloud-Assisted Services – CLASS 2015, Ljubljana, S... more Proceedings of the International Conference on Cloud-Assisted Services – CLASS 2015, Ljubljana, Slovenia, 5-6 November 2015 – Ljubljana: Fakulteta za gradbeništvo in geodezijo, Komisija za informatiko, knjižničarstvo in založništvo, 2015.
<p>Droughts are the major natural disasters affecting water availability le... more <p>Droughts are the major natural disasters affecting water availability leading to social, economic, and environmental challenges. Due to climate variability, investigation of climate change impact on droughts is of vital importance for sustainable societal and ecosystem functioning.  Western Ghats, a humid tropical region of India is selected as a case study to investigate the change in drought characteristics subjected to future climate change. In the last few decades, due to monsoon failure, the intensity of droughts has been identified to increase in this region making this study important. For future climatic variables, the ensemble of five Global Climate Models (GCMs) in the Coupled Model Intercomparison Project (CMIP5) are considered for the Representative Concentration Pathways (RCPs) 4.5 and 8.5. Standardized Precipitation-Evapotranspiration Index (SPEI) for the 12-month accumulated period is considered to assess the change in the drought characteristics during near (2011–2040), mid (2041–2070), and far future (2071–2100). The results indicate an increase in drought events in the future with maximum change during the far future for both RCP 4.5 and 8.5 scenarios. The major areas affected are in the southern part of Kerala and Karnataka. The change in total severity and duration of these drought events are high during the near future, moderate during the mid-future, and very high during the far future in both scenarios with RCP 8.5 being more severe. The findings show the variability in drought characteristics both spatially and temporally across the study area. The results will be helpful in identifying the hotspots prone to drought risk. This will serve as important guidance in improving the identification of causes, minimizing impacts, and enhancing the resilience to droughts in the study area. Further, the important implication of the study will be for water resource planning and management to strategize policies that emphasize on providing water in water-scarce regions during extreme drought situations.</p>
In this paper, a rainfall runoff model for coastal urban watershed con-sidering the effects of ti... more In this paper, a rainfall runoff model for coastal urban watershed con-sidering the effects of tidal variations using Finite Element Method (FEM) is presented. Overland flow is modeled using the mass balance equation considering the impervious character of the urban ...
Uploads
Papers by TI Eldho