Jens Grundmann

TU Dresden | TUD · Institut für Hydrologie und Meterologie

In Oman, the frequency of flash floods has significantly increased in recent years. This phenomenon is correlated with climate change, resulting in an intensification of the atmospheric water cycle. Consequently, a further escalation of flash floods can be anticipated in the future. In Oman, the issue of flash floods is exacerbated by the frequent...

2 Saxon state office for environment, agriculture and geology, Saxon Flood Forecasting Centre Flood forecasting and warning for small catchments are challenging due to the short response time of the catchments on heavy rainfall events. Thus, disaster managers are interested in extended lead times to initiate flood defence measures, which can be obt...

Obtaining real-time water level estimations is crucial for effective monitoring and response during emergencies caused by heavy rainfall and rapid flooding. Typically, this type of monitoring can be a difficult task, requiring river reach preparations and specialized equipment. Moreover, in extreme flood events, standard observation methods may bec...

Im Projekt "HoWa-innovativ" ist ein Demonstrator eines neuartigen niederschlagsbasierten Hochwasserfrüh-warnsystems unter Verwen-dung von Dämpfungsdaten kommerzieller Mobilfunknetze entwickelt worden. Dabei sind Daten einer weltweit vorhandenen Infrastruktur durch künstliche Intelligenz (KI) opportunistisch für eine völlig neue Anwendung, hier für...

A new hydro-meteorological precipitation and flood forecasting system for small catchments

Communicating uncertainties for flood warning in small catchments using ensemble hydrological forecasting

Im Projekt "HoWa-innovativ" ist ein Demonstrator eines neuartigen niederschlagsbasierten Hochwasserfrüh-warnsystems unter Verwendung von Dämpfungsdaten kommerzieller Mobilfunknetze entwickelt worden. Dabei sind Daten einer weltweit vorhandenen Infrastruktur durch künstliche Intelligenz (KI) opportunistisch für eine völlig neue Anwendung, hier für d...

Zusammenfassung Die Freiberger Mulde, die einen Teil des Freiberger Reviers entwässert, weist hohe Schwermetall‑, Arsen- und Sulfatbelastungen auf. Besonders der Abschnitt zwischen Berthelsdorf und Siebenlehn ist stark durch den Alterzbergbau sowie die Bunt- und Edelmetallurgie geprägt. Das Ziel von zwei Messkampagnen war die Identifikation aller p...

The handling of natural disasters, especially heavy rainfall and corresponding floods, requires special demands on emergency services. The need to obtain a quick, efficient and real-time estimation of the water level is critical for monitoring a flood event. This is a challenging task and usually requires specially prepared river sections. In addit...

The importance of optical measurement methods in hydrology is increasing in the last years. In contrast to conventional gauging techniques, they can be applied remotely, making the measurement safe for humans and equipment, even under difficult measurement conditions. One important hydrological parameter to measure is discharge. Deriving discharge...

Analysis of ensemble forecasts over successive forecast lead times for decision support in flood management

Unoccupied aerial systems (UASs) are frequently used in the field of fluvial geomorphology due to their capabilities for observing the continuum rather than single sample points. We introduce a (semi‐)automatic workflow to measure river bathymetry and surface flow velocities of entire river reaches at high resolution, based on UAS videos and imager...

This study assesses the suitability to use RGB and thermal infrared imagery acquired from an UAV to measure surface flow velocities of rivers. The reach of a medium-scale river in Hungary is investigated. Image sequences with a frame rate of 2 Hz were captured with two sensors, a RGB and an uncooled thermal camera, at a flying height that ensures t...

An automatic workflow to measure surface flow velocities in rivers is introduced, including a Python tool. The method is based on particle-tracking velocimetry (PTV) and comprises an automatic definition of the search area for particles to track. Tracking is performed in the original images. Only the final tracks are geo-referenced, intersecting th...

An automatic workflow to measure surface flow velocities in rivers is introduced, including a Python tool. The method is based on PTV and comprises an automatic definition of the search area for particles to track. Tracking is performed in the original images. Only the final tracks are geo-referenced, intersecting the image observations with water...

In this paper an automatic approach is proposed to measure flow velocity with an uncooled thermal camera. Hot water is used as thermal tracer. The introduced tracking algorithm utilizes the pyramidal Lucas-Kanade method and is especially suitable for thermal image data. The performance of the new tool is compared to traditional image-based tracking...

The problems of water resource management and its interaction with society have to be tackled from an integrated perspective taking into account the interdependence of environmental, political, social and economic factors. The conventional approaches being currently used, to study water resources management, lack to reflect the mutual relationship...

Knowledge of spatio-temporal rainfall patterns is required as input for distributed hydrologic models used for tasks such as flood runoff estimation and modelling. Normally, these patterns are generated from point observations on the ground using spatial interpolation methods. However, such methods fail in reproducing the true spatio-temporal rainf...

Knowledge about the spatio-temporal rainfall pattern is required as input for distributed hydrologic models to perform several tasks in hydrology like flood runoff estimation and modelling. Normally, these pattern are generated from point observations on the ground using spatial interpolation methods. However, such methods fail in reproducing the t...

Coastal aquifers in arid and semiarid regions are particularly at risk due to intrusion of salty marine water. Since groundwater is predominantly used in irrigated agriculture, its excessive pumping – above the natural rate of replenishment – strengthen the intrusion process. Using this increasingly saline water for irrigation, leads to a destructi...

For finding optimal water management strategies in arid coastal regions efficiently, the behaviour of a numerical groundwater model for different extraction and replenishment scenarios is approximated by an artificial neural network using a novel approach for state space surrogate model development. Afterwards the derived surrogate is coupled with...

The complexity of water resources management increases when decisions about environmental and social issues are considered in addition to economic efficiency. Such complexities are further compounded by multiple uncertainties about the consequences of potential management decisions. In this paper, a new fuzzy-stochastic multiple criteria decision-m...

Abstract: The scarcity of freshwater resources in the Sultanate of Oman, makes it essential that both surface and groundwater resources are carefully managed. Introducing new water demand management tools is important, especially for the coastal agricultural areas (e. g. Al Batinah coastal region) which are affected by sea water intrusion. Based on...

The work introduces the use of a participatory process within the frame of an integrated water resources management (IWRM) to support decision makers in taking more informed decisions.

A surrogate modeling framework is developed in this study to circumvent the computational burden of high-fidelity numerical groundwater models for arid coastal aquifers. Two different surrogate models, namely, artificial neural network (ANN) and Gaussian process model (GPM) are trained to replace the computationally expensive numerical flow and tra...

The water resources management complexity increase when decisions about environmental and social issues are considered in addition to economic efficiency. Such complexities are further compounded by multiple uncertainties about the consequences of potential management decisions. In this paper, a new fuzzy-stochastic multiple criteria decision-makin...

Mountain catchments are the major contributer to the total renewable water yield in (semi-)arid regions. Consequently, a distinct, well adapted assessment is essential for this hydrogeologic setting. Due to generally deep lying groundwater tables, the hydrologic response of a mountain catchment is divided into subsurface flow components and surface...

Global change and its consequences require reliable and robust methods for an efficient and sustainable management of increasingly scarce water resources. Integrated approaches are recommended (e.g. river basin management or integrated water resources management) to ensure a long-term management and development of watersheds and their resources con...

Al Batinah coastal area is the main agricultural region in Oman. Agriculture is concentrated in Al Batinah, because of more fertile soils and easer access to water in form of groundwater compare to other administrative areas in the country. The region now is facing a problem as a result of over abstraction of fresh groundwater for irrigation from t...

The planning and implementation of effective water resources management strategies need an assessment of multiple (physical, environmental, and socioeconomic) issues, and often requires new research in which knowledge of diverse disciplines are combined in a unified methodological and operational frameworks. Such integrative research to link differ...

Global change and its consequences require reliable and robust methods for an efficient and sustainable management of increasingly scarce water resources. Integrated approaches are recommended (e.g. river basin management or integrated water resources management) to ensure a long-term management and development of watersheds and their resources con...

The management of complex interacting hydrosystems is challenging if in addition to the physical processes also socio-economic and environmental aspects have to be considered. This causes conflicts of interests among various water actors with mostly contradicting objectives and uncertainties about the consequences of potential management interventi...

The International Water Research Alliance Saxony (IWAS) is addressing the global challenges concerning water quality in the areas of drinking water and sanitation, agricultural irrigation and the quality of surface and ground waters, as well as developing specific ecosystem-relevant services to be implemented on an exemplary basis in selected model...

The estimation of soil hydraulic parameters for the description of the highly non-linear hydraulic conductivity and water retention curve is of crucial importance for numerical modeling of water and solute transport in the vadose zone. Soil cores have been taken from different depths of a sandy soil of an agricultural field site located in the Bati...

Irrigation farming is the greatest consumer of the Earth’s freshwater resources. In the light of an increasing water demand caused by growing population, effective methods are required that use the available water resources efficiently and increase the overall productivity of irrigation systems. In this contribution, a combined approach of simulati...

Groundwater systems in arid coastal regions are particularly at risk due to limited potential for groundwater replenishment and increasing water demand, caused by a continuously growing population. For ensuring a sustainable management of those regions, we developed a new simulation-based integrated water management system. The management system un...

The conventional methods used to solve multi-criteria multi-stakeholder problems are less strongly formulated, as they normally incorporate only homogeneous information at a time and suggest aggregating objectives of different decision-makers avoiding water–society interactions. In this contribution, Multi-Criteria Group Decision Analysis (MCGDA) u...

An amplified interconnectedness between a hydro-environmental and socioeconomic system brings about profound challenges of water management decision making. In this contribution, we present a fuzzy stochastic approach to solve a set of decision making problems, which involve hydrologically, environmentally, and socioeconomically motivated criteria...

This paper evaluates the remediation potential of a salinized coastal aquifer by utilizing a scenario simulation. Therefore, the numerical model OPENGEOSYS is first validated against analytical and experimental data to represent transient groundwater level development and variable density saline intrusion. Afterwards, a regional scale model with a...

Sea water intrusion into the coastal aquifer system of the Al Batinah coastal area in Oman as a result of over abstraction has been addressed by the Government since the beginning of 1990s. However, the water situation in the region is still at risk and the sea water intrusion is expanding more and more inland. Agriculture is the main consumer of g...

Flash floods in ephemeral rivers are characterized by pronounced runoff dynamics, rapidly rising hydrographs, and infiltration through permeable river beds. In numerous countries, this infiltration—which is commonly referred to as transmission loss—is artificially increased by means of dams in order to promote groundwater recharge of local aquifers...

The conventional methods used to solve multi-criteria multi-stakeholder problems are less strongly formulated, as they normally suggest aggregating the objectives of different decision-makers to develop a compound objective avoiding relative powers of the stakeholders, which has an important effect on the results. This is even more difficult as mul...

An improved understanding of hydrological and socio-economic connection is necessary for efficient hydrosystem management and decision-making. However, it is challenging to conceptualise complex interactions in hydrosystems if in addition to the physical processes also socio-economic and environmental aspects are considered. In this contribution we...

It is challenging to model complex groundwater systems if in addition to the physical processes also socio-economic and environmental aspects are considered. In this contribution we propose a new approach for integrated groundwater resources management decision support, utilizing Object-Oriented Bayesian Networks (OOBN) and simulation-based optimiz...

Water for irrigation farming is severely limited in arid and semi-arid regions, hence reliable and robust strategies are needed that allow to use the available resources efficiently. Controlled deficit irrigation (DI) is one strategy that can help to use water in an effective way while still ensuring considerable yields from harvest. It needs preci...

For ensuring an optimal sustainable water resources management in arid coastal environments, we develop a new simulation based integrated water management system. It aims at achieving best possible solutions for groundwater withdrawals for agricultural and municipal water use including saline water management together with a substantial increase of...

Improving groundwater recharge is of high importance for a sustainable water resources management in many dryland regions. Ephemeral rivers, which are quite common for those regions, contribute to groundwater recharge due to infiltration through permeable river beds. In numerous countries, this infiltration is artificially increased by means of dam...

This paper deals with numerical modeling of groundwater systems. We present the implementation of an approach to solve a moving boundary problem for a dynamic water table within an invariant finite element mesh. The modeling software is successfully validated against laboratory experiment data for an unconfined, density-dependent benchmark. The val...

In this paper we present a new simulation-based integrated water management tool for sustainable water resources management in arid coastal environments. This tool delivers optimised groundwater withdrawal scenarios considering saltwater intrusion as a result of agricultural and municipal water abstraction. It also yields a substantially improved w...

For ensuring an optimal sustainable water resources management in arid coastal environments, we develop a new simulation based integrated water management system. It aims at achieving best possible solutions for groundwater withdrawals for agricultural and municipal water use including saline water management together with a substantial increase of...

In arid and semi-arid regions where water is scarce, farmers heavily rely on irrigation in order to grow crops and to produce agricultural commodities. The variable and often severely limited water supply thereby poses a serious challenge for farmers to cope with and demand sophisticated irrigation strategies that allow an efficient management of t...

Regions in arid and semi-arid countries that are used for agriculture are highly water-stressed and their water resources are often overexploited. In this paper, we present the concept of simulation-based optimization for incorporating numerical simulation models into the integrated water resources management concept. To develop a new management sy...

For ensuring both optimal sustainable water resources management and long-term planning in a changing arid environment, we propose an integrated Assessment-, Prognoses-, Planning- and Management tool (APPM). The new APPM integrates the complex interactions of the strongly nonlinear meteorological, hydrological and agricultural phenomena, considerin...

In this contribution we introduce a stochastic framework for decision support for optimal planning and operation of water supply in irrigation. This consists of: (i) a weather generator for simulating regional impacts of climate change on the basis of IPCC scenarios; (ii) a tailor-made evolutionary optimization algorithm for optimal irrigation sche...

The optimization of an aquifer's "safe yield", especially within agriculturally used regions, is one of the fundamental tasks for nowaday's groundwater management. Due to the limited water ressources in arid regions, conflict of interests arise that need to be evaluated using scenario analysis and multicriterial optimization approaches. In the cont...

Temporal and spatial variability in the rainfall field is regarded as a substantial source of uncertainty in flood prediction with spatially distributed rainfall-runoff models. But often – due to a lack of data – the influence of rainfall uncertainty on the accuracy of flood predic-tion is not properly addressed. In our case, we can base our uncert...

Distributed watershed models constitute a key component in flood forecasting systems. It is widely recognized that models because of their structural differences have varying capabilities of capturing different aspects of the system behaviour equally well. Of course, this also applies to the reproduction of peak discharges by a simulation model whi...

Eine große Unsicherheitsquelle bei der Hochwasservorhersage mittels räumlich verteilten Niederschlag-Abfluss-Modellen stellt die raum-zeitliche Variabilität des Niederschlagsfeldes dar. Mangels geeigneter Daten wird in vielen Studien diese Unsicherheitsquelle nur unzureichend berücksichtigt. In der vorliegenden Studie werden Ensembles von jeweils 1...

The objective of the project HORIX is the development of an efficient management tool for flood forecasts in meso-scale watersheds. Thereby the flood warning should be faster and more reliable than the classical methods. The basis of the investigation is the analysis of important flood relevant processes: forecast of rainfall events – rainfall-runo...

Das Ziel der hydrologischen Untersuchung war, die Möglichkeit von Hochwasserpräventionsmaßnahmen für das Schloss und den Schlosspark in Weesenstein aufzuzeigen und ihre Leistungsfähigkeit zu berechnen. Die Untersuchungen waren dabei auf Maßnahmen beschränkt, welche auf dem Gebiet des Schlossparks im Bezug auf eine Hochwasserprävention der Ortslage...

Modelling rainfall-runoff (R-R) processes using deterministic, spatial distributed, process-based models is affected by numerous uncertainties. One major source of these uncertainties origins from measurement errors together with the errors occurring in the process of data processing. Inadequate representation of the governing processes in the mode...