Click on the name of the organization in the list below to navigate to the experts on this page.

The Water Institute of the Gulf

Ehab Meselhe, Vice President of Engineering

Ehab Meselhe, Ph.D., P.E., has more than 20 years of experience researching coastal wetland hydrology, sediment transport, and computer modeling of coastal wetland, estuarine, and riverine systems. His multi-layered background includes work as an educator, researcher, and practitioner with extensive experience working with academic institutions, government agencies, and the private sector. He has been heavily involved in large-scale coastal ecosystem restoration programs in south Louisiana and the Florida Everglades. Dr. Meselhe is heavily involved in the numerical modeling being used by Louisiana to help refine the design of sediment diversions at Mid-Barataria and Mid-Breton along the Mississippi River.

Alyssa Dausman, Vice President of Science

Alyssa Dausman, Ph.D. has more than 20 years of experience working in hydrology, research plan development, and restoration project science and monitoring. Dr. Dausman previously served as the Science Director for the Gulf Coast Ecosystem Restoration Council, an independent federal agency created by the RESTORE Act in 2012. Dr. Dausman focused on Gulf restoration and science for the council, comprised of the governors of the five Gulf states and cabinet-level officials from six federal agencies. In addition to serving as the Institute’s Vice President for Science, Dr. Dausman will serve as the Chief Scientist of the RESTORE Act Center of Excellence for Louisiana.

Mead Allison, Director of Physical Processes and Sediment Systems

An expert on river, deltaic and coastal sedimentary processes, Mead Allison, Ph.D., has researched river delta systems for nearly 25 years. He is one of the foremost experts on the Mississippi River’s sediment transport processes. Prior to joining The Water Institute of the Gulf, he served the University of Texas as Associate Director and Senior Research Scientist at the Jackson School of Geosciences’ Institute for Geophysics. Dr. Allison has held faculty positions at Tulane University’s Department of Earth and Environmental Sciences and at Texas A&M University’s Department of Oceanography.

Tim Carruthers, Director of Coastal Ecology

Tim Carruthers, Ph.D. has a strong international reputation from more than 20 years working in coastal ecology, focusing on human impacts and management. His work has focused on assessing and leveraging ecosystem conditions to enhance adaptation to coastal change. He brings specific experience in developing ecosystem health indicators and solving problems by focusing on systems analysis. Carruthers has developed approaches to ecosystem condition assessment, and global syntheses of seagrass trends and processes. Synthesizing knowledge for communication to broad audiences, including coastal citizens, policy-makers and scientific colleagues, has been an ongoing focus throughout his career.

Melissa Baustian, Coastal Ecologist

Melissa Baustian, Ph.D. is a Coastal Ecologist with The Water Institute of the Gulf. She has more than 10 years of experience in researching the ecological responses of aquatic ecosystems to nutrient enrichment, eutrophication and hypoxia. Most of her research experience has been on the benthic ecology of the low-oxygen area, known as the “Dead Zone” in the northern Gulf of Mexico. Dr. Baustian's current research is focused on providing technical support in the data collection and development of analyses and models that will examine nutrientrelated dynamics from restoration efforts in Louisiana’s coastal zone.

Dallon Weathers, Coastal Scientist

Dallon Weathers has been working as a Coastal Geologist in Louisiana for the past 9 years. He is a Coastal Scientist within the Physical Processes and Sediment Systems group at The Water Institute of the Gulf, where his main interests are the physical processes and geomorphology of rivers, inlets, deltas, and beaches. In pursuing his research, Weathers has developed technical expertise in hydrographic and geophysical surveying, oceanographic instrumentation deployment, as well as data modeling and analysis with geographic information systems (GIS).

Christopher Esposito, Research Scientist: Water Resources

Christopher Esposito, Ph.D. is a Research Scientist with The Water Institute of the Gulf. He has nearly 10 years of field and modeling experience studying sediment transport and deposition in river deltas. His research is primarily focused on the connections between river channels and their floodplains, a topic which is closely related to channel management and planned river diversions in deltas. Prior to joining the Institute, Dr. Esposito obtained his Ph.D. at Tulane University and his master’s degree at The University of New Orleans. Before entering graduate school, Dr. Esposito taught math and environmental education in public high schools. His interest in coastal zone management in Louisiana was sparked while leading students on field trips throughout the Mississippi River Delta.

Deltares USA

Toon Segeren, president of Deltares USA

Dr. Toon Segeren holds an engineering degree from Wageningen University, The Netherlands, in water management and hydrology and a PhD degree in Irrigation Engineering from Utah State University, United States of America. In 1996, Toon joined Delft Hydraulics as a senior researcher/consultant. For a number of years, he was involved in research and development projects for Dutch regional water authorities and municipalities with a focus on operational systems. In 1999, Toon was appointed department head, regional and municipal water management, Delft Hydraulics. From 1999 until 2002, Dr. Segeren was also employed part time by the Netherlands Organization of Regional Water Authorities as the coordinator of international affairs. In 2003, Toon was appointed as the deputy director, inland water systems with Delft Hydraulics. After the merger of Delft Hydraulics into Deltares, Toon was appointed as the Director Inland Water Systems and later Director Groundwater and Subsurface and became member of the Management Team of Deltares. Toon is also a member of several steering committees within the Netherlands. In 2008, Toon became President of Deltares USA. Deltares USA is an independent research and specialized consultancy organization affiliated with Deltares. His key expertise is water management.

Edwin Welles, hydrologist, director Deltares USA

Edwin Welles is currently the Executive Director of Deltares USA, located in Silver Spring, Maryland. His focus is on operational systems, implemented in FEWS. He works with flood forecasting agencies and hydro power companies throughout the US and Canada to guide their implementations. He follows two lines of operational reasearch, the verification of river forecasts and the development of ensemble forecasting techniques. Prior to working with Deltares USA, he worked with the National Weather Service (NWS) developing their hdyrologic and meteorological forecast systems. In addition to the operational systems, Edwin Welles manages Deltares USA.

Edwin Elias, coastal expert

Dr. Edwin Elias is a specialist advisor/researcher in the fields of Coastal Systems and Sediment Dynamics at Deltares USA. He holds a Master’s degree and a Ph. D degree in Civil Engineering, Delft University of Technology, the Netherlands. In 2005 he joined WL | Delft Hydraulics (now Deltares) as a coastal researcher and advisor. In the period 2006-2011 he was stationed with the US Geological Survey in California as a visiting scientist responsible for supervising the USGS numerical (Delft3D) modelling efforts in the fields of hydrodynamics, sediment dynamics and morphodynamics.

Tiantian Yang: Hydrologist and Reservoir Scientist

Dr. Tiantian Yang is a hydrologist and reservoir scientist at Deltares USA. His expertise are (1) evolutionary optimization theory, (2) multi-criterion decision-making, (3) Artificial Intelligence and Data Mining, (4) Hydropower assets management and production, and (5) the interaction among human-built infrastructures, hydrology, and climate. Dr. Yang works with Bonneville Power Administration (BPA), Manitoba Hydro, Idaho Power, Tennessee Valley Authority (TVA), and National Weather Service with respect to the implementation, maintenance, and enhancement of the FEWS platform to agencies’ operational systems. In addition, Dr. Yang works with RTC-Tools and RiverWare for real-time control and decision-making. In addition, Dr. Yang holds a Researcher title at the University of California Irvine. The research of Dr. Yang and his students focus on a presidential-level, multi-campuses, and multi-million U.S.-China Clean Energy Research Center Water Energy Technology (CERC-WET) initiative. Dr. Yang earned his Ph.D. and Master degree on civil engineering and mechanical Engineering from the University of California Irvine in 2010 and 2015, respectively. Dr. Yang got his Bachelor degree from Tsinghua University on mechanical engineering in 2009. Dr. Yang is an active researcher in academia and his work has been published in many premium journals, including “Water Resources Research”, “Hydrological Earth System Science”, “Environmental Modeling and Software”, etc.


Wiel Tilmans, director Hydraulic engineering and Deltares responsible for USA business development

Mr. Tilmans has been Delft Hydraulics' project manager in projects all over the world, notably in Europe (for the prestigious Venice Storm Surge Barrier Project), Africa, Middle East, Asia, North America and the Caribbean. His overseas work included assignments as coastal expert in project formulation and appraisal missions for the Dutch Overseas Development Aid, German Overseas Development Aid, and international organisations such as UNEP, UNESCO, European Community), Kuwait Fund and Asian Development Bank. Mr. Tilmans also has been resident engineer Delft Hydraulics' USA affiliate Engineering Hydraulics Inc., Seattle. USA.. Mr. Tilmans also was WL | Delft Hydraulics' director business development for South-East Asia. From 1997 till 2007 he held the position of director Marine, Coastal and Industrial Infrastructure, and was member of the management board of Delft Hydraulics. After the merger of Delft Hydraulics within Deltares (2008), Mr. Tilmans now as Director Hydraulic Engineering is member of the management board of Deltares, responsible for the region Middle East and North Africa, region Europe and thus recently appointed for region USA/Canada. He equally is responsible for the broad area of Hydraulic Engineering within Deltares, consisting of the following areas of expertise: harbour and marina developments; hydraulic structures; coastal engineering; offshore engineering; wave modelling; port and coastal structures; sea defences; intake/outfall structures; recirculation studies; water, sewage and industrial pipeline systems; sustainable energy. These activities are organized as a business unit with 4 departments incl. physical scale modelling in various wave/current flumes, wave/current basins, multiphase loop and the large-scale Delta Flume, all of which are the responsibility of the unit. The unit has some 110 specialists, most of which have academic or higher university degrees in various technical disciplines.

Roelof Stuurman, urban water and soil expert

Roelof Stuurman is specialist in integral management of environment, water and soil: hydrogeological systems analysis on a regional and local scale in support of spatial -, environmental- and water policy planning. Research is focused on the relation groundwater- surface water in the upper meters of the subsurface (water quality, water dynamics) and on research on seepage processes in relation to surface water base flow conditions, ecology and water quality. Groundwater generalist: flow processes, water quality, water temperature, isotopes, geology, subsidence, fresh-salt processes, monitoring network design. Urban water: research on the interaction of surface water-ground water-communal water-ecology within the urban area (urban water systems analysis, including ground subsidence), quantification of integral municipal water system, design of municipal (ground) water monitoring networks. Specialist in natural and man-made (hydro-) geological hazards. Risk analysis advisor in various lawsuits concerning material damages. Some recent projects:
  • 2017 – present: Rebuild by Design: San Francisco Bay Challenge, United States, research and advise. Designing in cooperation with architects, urban planners, landscape architects, health specialists
  • 2017 – present, Resilient Bridgeport, United States, research and advise, One week field visit, physical geographical system analysis and presentation of results and advises to local (governmental) stakeholders
  • 2016 – present: Mirabeau rain water garden, New Orleans, United States, advisor/research. Design, implementation and analysis of a groundwater monitoring network. Mapping the shallow geology and creating a hydro-geological subsurface model. Numerical modelling of the groundwater system and risk assessment of water storage to the surroundings. Design groundwater drainage solutions to neutralize risks. Study of hydro chemical processes
  • 2015 - present Dutch Dialogues Virginia: Life at sea level, United States, groundwater and subsurface processes specialist
  • 2014 – present: Rebuilt by Design, New York State, Long Island, United States, research subsurface and groundwater

Gennadii Donchyts, remote sensing & software development specialist

Gennadii Donchyts is specialized in remote sensing, geospatial processing and software development. He worked on multiple international research and consultancy projects, focusing on solving complex multi-disciplinary challenges and designing new algorithms for a better management and visualization of scientific data. For the last 20 years, Mr. Donchyts participated in various international projects, financed by TACIS, UNDP, EURATOM, INTAS, CRDF, DANCEE, SIDA, USAID, which required profound knowledge of the modern software development techniques, database design and various agile software and project management methods, including SCRUM (Certified Scrum Master), Test-Driven Development, and extreme Programming. Before starting his Ph.D., he has been a technical lead of a team, working on the development of new integrated modelling software of Deltares (Delta Shell). During recent years, his main focus has shifted to the development of new methods of Remote Sensing for the detection of surface water from Earth Observation data at planetary scale. The later involves processing of multitemporal, multisensory, and multi-petabyte satellite data acquired by optical and radar satellites during the last decades. Gennadii developed the Deltares Aquamonitor: a public tool in which you can view the water and land changes around the globe, in the last 30 years. Gennadii was an invited speaker at a yearly summit of Google.

Joachim Rozemeijer, water quality expert

Dr Joachim Rozemeijer has been working for Deltares since 2002 as a researcher in water quality and hydrology. He worked on various projects dealing with water quality monitoring, groundwater-surface water interactions and water conservation. From 2006 Joachim worked on his PhD-project DYNAQUAL. The goal was to measure and understand dynamics in water quality and to assess the consequences for monitoring, modelling, and water management. From 2010 until present, Joachim coordinated several Deltares projects on water quality monitoring, agricultural drainage, and effect quantification of mitigation options. He studied the effects of controlled drainage in agriculture as a water and nutrient conservation measure. He also initiated the National Monitoring Network for Agricultural Headwaters (MNLSO), which is used to report on the effects of the Dutch manure Policy to the European Government. In addition, he has initiated and coordinates a project that will enable farmers to measure nitrate concentration using smartphones in order to link nutrient losses to their farming practices. Joachim coordinates the ecosystem monitoring and modelling strategic research program at Deltares.

Margreet van Marle, expert in remote sensing and climate change

Margreet van Marle has a background in hydrology and has over 5 years experience in GIS, satellite remote sensing and biogeochemical modelling. During her master at the Vrije Univeristeit she developed an interest in remote sensing of the hydrological cycle. After her master degree she started a PhD research and aimed to gain more insight in tropical deforestation patterns, fire dynamics, and their interaction, especially over the past decades. Consistent data on forest loss dynamics are important to study the global carbon cycle, to estimate the potential of reducing deforestation for reducing greenhouse gas emissions. She developed several deforestation and fire emissions datasets using and combining satellite remote sensing with visibility observations from weather stations and modelled data. Ms. van Marle developed a historic global fire emissions inventory since 1750, which will be used in the Intergovernmental Panel on Climate Change’s (IPCC) Coupled Model Intercomparison Project phase 6 (CMIP6). She presented her work at several international conferences and her research resulted in international publications in peer-reviewed journals. Furthermore she supervised BSc students in Earth Sciences during their field practicals in physical geography and lectured in statistics and environmental remote sensing to both BSc and MSc students at the Vrije Universiteit Amsterdam. In 2017 she started working at Deltares and is responsible for applying remote sensing techniques for geo-engineering applications. Furthermore her focus is on soil subsidence and critical infrastructure.

Stuart Pearson, coastal expert

Stuart Pearson is specialized in hydrodynamic and morphodynamic modelling of coastal systems. Recently, he led the development of the BEWARE system for predicting floods on coral reef-lined coasts and low-lying tropical islands in a joint project with the U.S. Geological Survey. He is currently also carrying out PhD research at Delft University of Technology, where he is investigating sediment transport pathways and nourishments at tidal inlets in the Dutch Wadden Sea as part of the SEAWAD/Kustgenese2 project. He completed his MSc in the Coastal and Marine Engineeering and Management (M.Sc. CoMEM) program at TU Delft, carried out jointly with the University of Southampton and the Norwegian University of Science and Technology (NTNU). While at NTNU, he also performed research on modelling the erosion of permafrost coastlines in the Arctic. Prior to beginning his MSc, he was employed as a coastal modeller at W.F. Baird & Associates Coastal Engineers in Canada for over two years. At Baird he was primarily involved in hydrodynamic and sediment transport modelling of rivers and coastal regions. He completed his BASc in Civil Engineering at the University of Waterloo in Canada.

Jarno Verkaik, groundwater flow modeler and software developer

Jarno Verkaik has a broad experience in the fields of Groundwater Flow Modeling and Scientific Software Development. Since he graduated on parallel solvers at TNO in 2003 he worked on various numerical codes, for example, on processing radar data, simulation of glass melting, ultrasound wave propagation and crash-test simulation for the automotive industry. About a decade ago he started at TNO as a groundwater modeler for the Netherlands Hydrological Model and as a modeler for fresh-salt groundwater interaction on a regional scale. His work shifted from modeling to code development and as a core member of the Netherlands Hydrological Model he is now responsible for the software development of the Netherlands Hydrological Instrument. Mr. Verkaik is the initiator of several innovative, MODFLOW related, products like iMOD-MT3D, iMOD-SEAWAT, HydroConnect and parallel MODFLOW-USG, that is currently being developed in cooperation with the USGS, Utrecht University and Delft University of Technology. Within these developments he has mostly the role of both developer and code architect, but for several of these developments he is also project leader and supervisor of graduate students.

Julien Groenenboom, expert in environmental hydrodynamics

Julien Groenenboom is a consultant/researcher in the field of environmental hydrodynamics. He holds a Master’s degree in Civil Engineering, Delft University of Technology, The Netherlands. Julien is mainly working on the numerical (3D) modelling of marine and coastal systems. Most of the projects he is involved in are related to salt water intrusion. Furthermore, he has provided multiple trainings in using Delft3D 4 and Delft3D Flexible Mesh.

Joan Sala Calero, expert data management and image processing

Joan Sala graduated in 2009 in Computer Science from the Polytechnic University of Catalonia (UPC) and his main focus resides in GIS, data management, image processing and remote sensing. After his studies, he worked in TRE-Altamira contributing to its interferometric synthetic aperture radar (inSAR) image processing chain, specializing on data georeferencing and visualization. In the following years, his interest shifted into Marine Information Systems and data management which he could apply in the MyOcean project that turned into the Copernicus Marine operational service funded by the European Commission. At 2016, he joined Deltares to continue working on EU funded data management projects such as the Water Switch-ON and the Foreshore Assessment with Space Technology (FAST), both OGC (Open Geospatial Consortium) standards compliant software platforms. In parallel, Mr. Sala worked in disaster risk management tools such as Delft-FIAT a flood impact assessment tool to evaluate the economic impacts of flood events.

Roeli Suiker, communications expert

Roeli Suiker is specialist in communications at Deltares. She studied Business Economics at the Erasmus University in Rotterdam and has been working for Deltares for about 18 years. She is responsible for communications about the theme ‘flood risk’.

She was responsible for the communications strategy of the Delta Flume at Deltares, an experimental research facility that can make the highest artificial waves in the world. The Delta Flume made world news: from the BBC news to Discovery Channel and CBS.

She also coordinated the press when Dutch researchers made a computer simulation of the Alcatraz escape in December 2014, which went viral. Roeli has been host at the Deltares booth at AGU since 2013.