Umamahesh V. Nanduri

National Institute of Technology, Warangal | NITW · Department of Civil Engineering

Multi-objective optimization of water distribution networks (WDNs) is crucial for achieving a balance between cost, equity, and reliability. The present study conducts a comparative analysis, evaluating the effectiveness of four multi-objective optimization algorithms implemented within the EPANET framework for the optimal design of three distinct...

The effect of climate change on water availability and agriculture water demand is crucial for assessing agricultural productivity and economic development in semi-arid regions. The present study examines the crop water requirement (CWR) and irrigation water requirement (IWR) of the Bhadra and Tungabhadra (TB) command areas, with a focus on forecas...

This research examines the impact of climate change and urban expansion on urban drainage systems in Hyderabad (Zone-XII, Zone-IV&V), India. It employs a Markov chain-based framework to simulate future climate and land changes. Integrated 1D-2D PCSWMM model is used to assess the hazards posed by these changes. Present and future extreme rainfall ev...

Accurate streamflow simulation is crucial for effective hydrologic forecasting and water resource management. This study introduces a nested discretization scheme aimed at refining catchment delineation based on the spatial heterogeneity of its characteristics. The scheme aims to align with the assumption of spatial homogeneity within a hydrologic...

The flash drought has gained widespread attention as a result of its rapid onset with severe impacts. However, a comprehensive assessment of different flash droughts based on various modulators is not carried out over India to date. Here, we attempt to answer the following research questions, (i) What is the status of different flash drought events...

Accurate prediction of streamflow is essential at both the outlet and interior points for effective water resource management. This study aimed to investigate whether improved simulation results at the catchment outlet through Multi-Model Averaging (MMA) can be translated to interior ungauged points in a catchment. To achieve this, the study consid...

Cotton cultivation in India is of vital importance to the national economy. However, the susceptibility of cotton crops to climate change poses significant challenges. Recognizing the spatial heterogeneity of climate change's influence, comprehending its potential repercussions on cotton productivity is crucial. This research examines the effects o...

In urban areas of developing countries, due to industrialization and population growth, water demand has been increasing significantly, thereby increasing stress on the existing water distribution systems (WDSs). Under these circumstances, maintaining equity in the allocation of water becomes a significant challenge. When building an intermittent w...

Ensemble Prediction Systems (EPS) from a single Numerical Weather Prediction (NWP) model often miss out on a few extreme events. Similarly, a single hydrological model cannot capture all types of flows, such as flood peaks, occurring within a watershed due to the inaccurate representation of the real world processes in their mathematical structure....

In general, the impact of two different connected extreme events is noticed on the same duration and spatial area. However, the connected extreme events can have footprint over different temporal and spatial scales. Thus, this article analyses the connected extreme events over India using the spatio-temporal compounding technique to understand the...

Event-based hydrological models are extensively adopted for the estimation of design floods and in operational flood forecasting frameworks. However, an accurate estimation of the initial hydrologic condition (IHC) is essential in enhancing the predictive capability of an event-based hydrological model. Hence, in this study, IHCs of an event-based...

Climate change significantly impacts the natural systems, accelerating the global water cycle, and impacting various ecosystem services. However, the expected effects of climate change on the frequency and severity of extreme events on hydrological systems vary significantly with location. The present study investigates the uncertainties engulfed i...

Agricultural productivity is significantly affected by weather and climate extremes such as droughts and heat waves. Despite several studies addressing the impact of individual and compound extremes on crop yields, there needs to be more comprehensive understanding of their duration thresholds beyond which the crop declines significantly. Hence, in...

As a widespread natural hazard, droughts impact several aspects of human society adversely. Thus, the present study aims to answer the following research questions; (i) What are the expected variabilities in different drought conditions over India in the future? (ii) How the population exposure to drought varies under different climate change and p...

This study addresses the issue of scant availability of sub-daily precipitation data by introducing a novel selection methodology named ‘Pattern Mapping’ (PM) within the existing Method of Fragments (MOF) framework for the disaggregation of daily precipitation. PM introduces multiple statistics based criterion in the selection of fragments thus enh...

The ensemble forecasts from Numerical Weather Prediction (NWP) models are considered as essential elements for operational hydrologic forecasting. However, these forecasts are burdened with significant inherent biases and cannot be used directly for hydrologic forecasting. Therefore, the present study examines the capability of ensemble precipitati...

The current chapter provides an overview of climate change impact assessments in water resources, as well as the techniques and procedures that underpin it. In addition, the generally utilised impact analysis process, such as the integration of climatic and hydrological models, is discussed. The authors have produced a case study over a river basin...

The agricultural drought significantly affects the socio-economic sectors in the agrarian country like India. Though there is a larger variability in the drought characteristics, the time to propagation from meteorological to agricultural drought is not investigated at regional scale in India. The Standardised Precipitation Evapotranspiration Index...

Due to the dual pressure of rapid urbanization and climate change, urban flooding has become more common. Thus, for effective planning and mitigation strategies, it is of paramount interest to quantify the generated runoff and prioritize the urban critical sub-catchments. The present study investigates flood inundation in Hyderabad urban setting (z...

Irrigation water availability is the main driver to determine cropping patterns, whereas the different water storages will potentially reduce because of changes in climate. Therefore, cropping patterns should be adjusted to meet this challenge. In this study with three objective functions 1) Maximization of net benefit 2) maximization of yield and...

Rainfall forecasting and its spatio-temporal variability is important for many hydrological applications. It is critical to understand the uncertainty and verify the quality of rainfall forecasts provided by Numerical Weather Prediction (NWP) models. In the present study, the National Center for Environmental Prediction (NCEP) Global Forecast Syste...

Understanding the devastating nature of drought, this work has assessed the variability in the Severity-Area-Frequency (SAF) curve using Standardised Precipitation Evapotranspiration Index (SPEI) as meteorological drought indicator over Maharashtra, India. The future meteorological outputs from 19 Global Circulation Models (GCMs) of the NASA Earth...

Assessing the risk on agricultural system is important for agricultural sustainability. The present study analyses the agricultural drought risk with respect to different drought severities. Different drought indices namely SPEI, SSI, VCI and TCI are used to evaluate the conditional probability. The non-stationary analysis is carried out for SPEI a...

As a costliest natural hazard, drought profoundly affects water resources, agriculture, and socio-economic sectors in India. In spite of large spatio-temporal variability in droughts, the propagation time from meteorological to hydrological droughts is not examined at local scale over India. In this study, the meteorological and hydrological variab...

The surface water resource, i.e., mostly streamflow/discharge, is the outcome of the complex hydrological and climatic interactions (directly and/or indirectly) which are modulated by the atmosphere–ocean circulation. In the present scenario of climate change, it is inevitable to study and analyse the surface water resources availability and their...

In the present study a total of 201 research articles around the globe over the review period from 2001 to 2021 are identified and investigated. The study has identified some of the grand challenges associated with Ensemble Flood Forecasting (EFF). In addition, future opportunities include development of quality-controlled datasets for longer durat...

Indian cities are exposed to increasing threat of urban flooding due to rapid urbanization and climate change. As a result, life in the affected city comes to a halt with power cuts, roads jammed, houses inundated, accidents and loss of life. A similar event occurred on October 2020 has paused the life in Hyderabad city affecting more than thousand...

Due to present climate change scenario, it is inevitable to interpret return period, risk, and reliability of hydrologic extreme under non-stationary condition. The present study aims to understand the crucial design parameters by introducing physical based covariates in the location parameter of GEV distribution. The analysis is carried out over t...

It is well understood that India is largely exposed to different climate extremes including floods, droughts, heat waves, among others. However, the exposure of co-occurrence of these events is still unknown. The present analysis, first study of its kind, provides the projected changeability of five different compound extremes under three different...

Surface imperviousness is vital basin parameter and plays a major role in watershed hydrology especially in an urban environment. Estimation of surface imperviousness is crucial but tedious task in urban watershed modelling as urban land use changes very frequently. The challenge encountered in calculating surface imperviousness is the need for a s...

The present study looks into the Hyderabad urban floods of October 2020 from a geospatial perspective. The spatial extent and severity of the flooding event for a part of the urban catchment (Zone-12) of Hyderabad city are modelled using HEC-RAS 1D-2D considering 13 October 2020 rainfall event. The study compares the present flooding to the previou...

Atmospheric warming is expected to increase the magnitude and frequency of extreme climatic events namely floods, droughts, heat waves, and so on. Thus, the present study attempts to answer the following research questions; (i) What are the possible implications on future heat wave events due to the projected temperature? (ii) What are the expected...

Hydrological forecasting plays a significant role in effective operation of water resources planning and flood mitigation systems. In the present study ʋ- Support Vector Regression method is implemented to develop a model to forecast stream flow at Tekra site on River Pranahita with one day lead time. River Pranahita is a tributary of River Godavar...

The present study aims to answer the following two research questions using the future outputs from 19 GCMs of the novel NASA Earth Exchange Global Daily Downscaled Projections (NEX‐GDDP) under two Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios. (a) What will be the possible variability of future meteorological drought properties...

Climate change and urbanization are two major ongoing process worldwide and in past few years their impact on ground started becoming visible as increased events of intense rainfall and urban floods. Rapidly growing urban areas are liable to greater risk of climate change. Fine-scale rainfall forms the most important input to achieve greater accura...

Most of the techniques formulated for real-time flood forecasting in India, are based on statistical, and deterministic approach. Any error in the observations, model structure, model parameters, and initial conditions, which are unknown initially, propagates through the flood forecasting system to produce uncertain prediction of flood values. Dete...

Recent studies report that the extreme rainfall characteristics in most parts of the globe exhibit temporal non-stationarity. Therefore, modeling the nonstationary behavior of extreme rainfall for different water resources applications is vital. When modeling non-stationarity in extreme rainfall series, previous studies consider a single threshold...

In general, water resources are becoming more vulnerable under the influence of climate change, especially for the agricultural dominant countries in the world as they are more fragile to the climate variability. Water harvesting possibilities are evaluated based on the historical observations and downscaled future projection of rainfall from the G...

In the persisting climate change scenario, it is of great concern to revisit, rethink, and improve the existing computational aspects of the drought indices. In general, the commonly used drought indices do not encompass environmental changes. Hence, the primary objective of this study is to incorporate the large-scale climatic oscillations in deve...

Understanding the spatio-temporal distribution of rainfall characteristics has a major role in assessing the availability of water resources over a catchment. Therefore, it is necessary to understand the changes in rainfall characteristics using gridded precipitation data and robust statistical analysis for making decisions. In this study, the tren...

Uncontrolled urbanization and climate change play a significant role in urban flooding. The condition in which rainfall excess exceeds the drainage capacity of storm water drains is called urban flooding. Urbanization disrupts the natural water balance by increasing impervious areas and reduction in infiltration. This increases runoff from urban ca...

This paper presents a genetic algorithm and nonlinear programming (GA–NLP) hybrid model to derive steady state optimal reservoir operating policies for a multi-purpose reservoir. In the present study, the objective is maximizing the net benefits from all the crops in the command area considering yield response to water deficit and the hydro-power g...

Flood is the most common natural disaster upsetting the highest population of the world. In recent times, severe floods in urban areas are occurring more frequently owing to uncontrolled urbanization and climate change and it will continue to grow in upcoming years. Prevention of such events is not possible but with advancement of technology, flood...

This paper presents a Genetic Algorithm and Non-Linear Programming (GA-NLP) hybrid model to derive steady state optimal reservoir operating policies for a reservoir. In the present study, the objective is maximizing the yields of all the crops in the command area considering yield response to water deficit subject to constraints on reservoir water...

Stochastic weather generators are generally used to produce scenarios of climate variability on a daily timescale for hydrological modeling and water resource planning applications. Most of the available weather generators assume extreme rainfall series as stationary series. However, it is currently perceived that global climate change is increasin...

Understanding the magnitude and spatial variation of extreme rainfall events are required for decision making and adaptation strategies for flood risk. In Ho Chi Minh City (HCMC), heavy rainfall, which is considered as a main cause of floods, witnessed an increase in frequency and magnitude in last few decades. Although nonstationarity in extreme r...

Flood modelling inputs that are used to create flood hazard maps are normally based on the assumption of data stationarity for flood frequency analysis. However, changes in the behaviour of climate systems can lead to nonstationarity in flood series. Here, we develop flood hazard maps for Ho Chi Minh City, Vietnam, under nonstationary conditions us...

This book is a compilation of the high-quality papers from the International Conference on Emerging Trends in Water Resources and Environmental Engineering (ETWREE 2017). Written by researchers and academicians from prestigious institutes across India, the contributions present various scenarios and discuss the challenges of climate change and its...

In the context of climate change, the uncertainty associated with Global Climate Models (GCM) and scenarios needs to be assessed for effective management practices and decision-making. The present study focuses on modelling the GCM and scenario uncertainty using Reliability Ensemble Averaging (REA) and possibility theory in projecting streamflows o...

Space for water is now becoming guiding principle of urban planning because urban flooding is the major problem facing by most of the cities in India. Urban development in developing countries like India usually occurs with high population concentrating in small areas, with poor drainage conditions. People occupy floodplain areas in low flood years...

Space for water is now becoming guiding principle of urban planning because urban flooding is the major problem facing by most of the cities in India. Urban development in developing countries like India usually occurs with high population concentrating in small areas, with poor drainage conditions. People occupy floodplain areas in low flood years...

Urban floods are self-invited disasters which are responsible for huge property loss and in some cases loss of lives, self-invited in the sense man’s desire for more and more land, and uncontrolled infrastructure development is altering natural land use, land cover and stream flow paths. Thus, high-intensity rainfall for shorter time period is prod...

Uncontrolled urbanization and Climate change plays a significant role in urban flooding. The condition in which rainfall excess exceeds the drainage capacity of storm water drains is called urban flooding. Urbanization disrupts the natural water balance by increasing impervious areas and reduction in infiltration. This increases runoff from urban c...

Recently, human intervention and climate change have been proposed as the causes of changes in extreme water levels, which impact the likelihood of flooding, especially in coastal areas. In many studies, frequency analysis of extreme water levels has been conducted under nonstationary conditions, in which the parameters of a given distribution vary...

In the context of climate change, it is essential to quantify the uncertainty for effective design and risk management practices. In the present study, we have accessed the climate model and flood return level uncertainties over a river basin. Six high-resolution global climate models (GCMs) with two Representative Concentration Pathways (RCPs) are...

In this study, classification and regression based statistical downscaling is used to project the monthly monsoon streamflow over Wainganga basin, India using 40 global climate models (GCM) outputs and four representative concentration pathways (RCP) scenarios. Support vector machine (SVM) and relevance vector machine (RVM) are considered to perfor...

Evaluation of the changes in temporal scale and in extreme values of climatic variables is required for future hydrological modeling and policy-making. Different downscaling techniques are used to downscale global projections to the regional level but projections are not well simulated for extreme events because of uncertainty. In this study the ch...

Urban floods are caused due to increase in population density, development of urban infrastructure without paying due consideration to drainage aspects and increase in paved surfaces. Storm water modelling plays an important role in checking issues such as flash floods and urban water-quality problems. The SWMM (Storm Water Management Model) has be...

In the present study, spatio-temporal variability of hydrological components under climate change is analysed over Wainganga River basin, India. In order to address the climate change projection, hydrological modelling is carried out using a macro scale, semi-distributed three (3)-Layer Variable Infiltration Capacity (VIC-3 L) model. The high-resol...

The major issue in water resource planning and management is determination of the optimal operating policy of a reservoir. In this study, GA-NLP hybrid approach has been applied. Genetic Algorithm (GA) is able to find the near optimal solution easily but for finding global optimal solution it will take too many function evaluations, so hybrid appro...

Since the global climate change altering the characteristics of extreme rainfall events, modeling the behavior of extreme rainfall is becoming indispensable. Among various physical processes, the El Niño Southern Oscillation (ENSO) cycle is a significant process that can trigger occurrences of extreme hydro-climatological events, such as floods, dr...

The infrastructure design is primarily based on rainfall intensity-duration-frequency (IDF) curves and the current IDF curves are based on the concept of stationary extreme value theory (i.e. occurrence probability of extreme precipitation is not expected to change significantly over time). But, the extreme precipitation events are increasing due t...

The global physical processes such as El Niño-southern oscillation (ENSO) and Indian Ocean dipole (IOD) have a significant impact on Indian extreme rainfall. Recent studies show that the impact of ENSO cycle on Indian rainfall has changed. Therefore, understanding the changes in the effects of these physical processes on extreme rainfall of an urba...

Urban flooding is one of the major challenges that India is facing every year to which a solid solution is not yet available. Rapid-growing urban areas are responsible for the ground sealing which affects the natural drainage system. As a result, all the rainwater is going to flow through drainage system. Most of the drainage network in the country...

In the present study, spatio-temporal variability of hydrological components under climate change is analysed over Wainganga River basin, India. In order to address the climate change projection, hydrological modelling is carried out using a macro scale, semi-distributed three (3)-Layer Variable Infiltration Capacity (VIC-3 L) model. The high-resol...

Climate change, a change caused by human activities and natural variability, will have significant impact on frequency of extreme climatic events including intense storms, heavy rainfall, droughts, and an alarming rise in sea level. The purpose of this work is to study the effect of climate change on the streamflow pattern of Wainganga river basin...

The present study analyzes the various uncertainties and nonstationarity in the streamflow projections over the Wainganga River Basin, India, under representative concentration pathways (RCPs) 4.5 and 8.5 using the 3-layer variable infiltration capacity (VIC-3L) model. The uncertainties associated with the multiple climate models, parameters, and r...

Since the substantial evidence of non-stationarity in the extreme rainfall series is already reported, the current realm of hydrologic research focusing on developing methodologies for a non-stationary rainfall condition. As the rainfall intensity duration frequency (IDF) curve is primarily used in storm water management and infrastructure design,...

Climate change, a change caused by human activities and natural variability, will have significant impact on frequency of extreme climatic events including intense storms, heavy rainfall, droughts, and an alarming rise in sea level. The purpose of this work is to study the effect of climate change on the streamflow pattern of Wainganga river basin...

Many bidding methods are available to evaluate the submitted bids in the construction industry. Based on the type of the projects and preference of clients, we choose different bidding methods. Most commonly used bidding methods are ‘Lowest Bid Method (LBM)’, ‘Average Bid Method (ABM)’, ‘Below Average Bid Method (BABM)’, ‘Swiss Challenge Method’, e...

The rainfall Intensity-Duration-Frequency (IDF) relationship is the primary input for storm water management and other engineering design applications across the world and it is developed by fitting an appropriate theoretical probability distribution to annual maximum (AM) series or partial duration series (PDS) of rainfall. The existing IDF relati...

The infrastructure design is primarily based on rainfall Intensity-Duration-Frequency (IDF) curves and the existing IDF curves are based on the concept of stationary extreme value theory (i.e., the occurrence probability of extreme precipitation is not expected to change significantly over time). But, the extreme precipitation events are increasing...

Present infrastructure design is primarily based on rainfall Intensity-Duration-Frequency (IDF) curves with so-called stationary assumption. However, in recent years, the extreme precipitation events are increasing due to global climate change and creating non-stationarity in the series. Based on recent theoretical developments in the Extreme Value...

Evaluating the impact of climate change at river basin level has become essential for proper management of the water resources. In the present study, Godavari River basin in India is taken as study area to project the monthly monsoon precipitation using statistical downscaling. The downscaling method used is a regression based downscaling termed as...

Hydrological forecasting plays a significant role in effective operation of water resources planning and flood mitigation systems. River flow forecasting is required to provide basic information on a wide range of problems related to the design and operation of river systems. In the present study ʋ- Support Vector Regression method is implemented t...

Storm water management and other engineering design applications are primarily based on rainfall Intensity-Duration-Frequency (IDF) curves and the existing IDF curves are based on the concept of stationary Extreme Value Theory (EVT). However, during the last few decades, global climate change is intensifying the extreme precipitation events and cre...

The infrastructure design is primarily based on rainfall intensity–duration–frequency (IDF) curves, and the existing IDF curves are based on the concept of stationary extreme value theory (EVT) (i.e. the occurrence probability of extreme precipitation is not expected to change significantly over time). But, the extreme precipitation events are incr...

The high intensity rainfall has a significant contribution in urban area flooding and understanding this high intensity rainfall over urban areas may help us to reduce the damage caused by urban floods. In this study, the changes in Hyderabad city daily and sub-daily (4-h) extreme rainfall are analyzed using various climate change detection indices...

Climate change is considered to be the greatest challenge faced by mankind in the twenty first century. Distribution and circulation of the waters of the earth become increasingly difficult to determine because of additional uncertainty related to anthropogenic emissions. Climate change and its potential hydrological effects are increasingly contri...

Along with other causes, such as rapid urbanization, the high intensity rainfall has significant contribution in urban area flooding. Understanding this high intensity rainfall over urban area may help us to reduce the damage caused by urban floods. Recent studies reported the relationship between El Niño-Southern Oscillation (ENSO) and Indian extr...

Land Use/ Land Cover (LULC) map is an important input in Geographical Information System (GIS) based hydrological modeling such as rainfall runoff modeling. Preparation of LULC map by satellite image or field visit is expensive in terms of money and time. The spectral characteristics in Google Earth (GE) images are very poor compare to satellite im...

Equity in water supply is one of the major problems faced in intermittent water distribution systems. A new index ‘uniformity coefficient’ is introduced to measure the equity in distribution of water within the network, which may be useful for performance evaluation of water distribution networks (WDNs). An iterative head‐driven analysis technique...

Water quality models are used to describe the discharge concentration relationships in the river. Number of models exists to simulate the pollutant loads in a river, of which some of them are based on simple cause effect relationships and others on highly sophisticated physical and mathematical approaches that require extensive data inputs. Fuzzy r...

The development and management of irrigation facilities has been recognized as the key to national development in India. Despite their high priority and massive investments, the performance of major irrigation projects has been disappointing. Substantial benefits can be achieved from relatively small increases in operating efficiencies. The main ob...

A reservoir operation simulation study is carried out to analyze the impact of alternative scenarios of a hydropower system operation on energy production and natural flow regime in the La Nga river basin in Vietnam. The current operation policy causes severe hydrologic alteration in the natural flow regime represented by 32 parameters of the Range...

A weekly irrigation planning LP model is formulated for determining the optimal cropping pattern and reservoir water allocation for an existing storage based irrigation system in India. Objective of the model is maximization of net annual benefit from the project. In an irrigation planning of a storage based irrigation system, initial storage of t...

Reservoir management is a highly complex problem, which includes the uncertainty in the inflows as well as in the objectives. Stochastic dynamic programming (SDP) has been widely used to develop the optimal operating policies of multipurpose reservoirs. In the recent years, fuzzy optimization has been used to incorporate the uncertainty caused due...

In this study optimal irrigation planning strategies are developed for the Nagarjuna Sagar Right Canal command in the semiarid region of South India. The specific objective of the study is to allocate the available land and water resources in a multicrop and multiseason environment and to obtain irrigation weeks requiring irrigation of a fixed dept...

The prediction of flow into a reservoir is fundamental in water resources planning and management. The need for timely and accurate streamflow forecasting is widely recognized and emphasized by many in water resources fraternity. Real-time forecasts of natural inflows to reservoirs are of particular interest for operation and scheduling. The physic...

Nodal demand satisfaction is one of the means to assess the performance of a Water Distribution Network (WDN). In most of the developing countries, the public water supply systems are not capable of meeting consumer demands. In such situations it is more appropriate to observe deviations in nodal demand satisfaction. Through this paper a new parame...

Erosion is a fundamental and complex natural process that is strongly modified by the activities such as land clearance, agriculture, forestry, construction, surface mining and urbanisation. Inventory on soil loss is vital for effective soil conservation planning of a watershed for sustainable development. An alternative sustainable practice is mai...

Optimal operation of reservoir has been an active area of research for many years. Various techniques have been developed and adopted for reservoir operation incorporating the uncertainty due to stochastic nature of inflows and demands. However there is not much literature reported on models incorporating uncertainty caused due to imprecise goals a...