Graduate Intern Fluvial Flooding Modelling

MSc Thesis: “Comparing and modelling breach development in different hydraulic models”

The flood safety standards in the Netherlands are based on flood risks, which are determined by running flood scenarios for all locations prone to flooding. Previous MSc theses at Royal HaskoningDHV have shown that flood simulations are sensitive to the description of breach development (see Westerhof (2019) & Klein Wolterink (2022)). The assumptions used while describing breach development have a significant impact on the discharge through a breach and therefore on the flood safety standards in the Netherlands. This leads to several questions:

1. The actual breach development depends on the materials used in the dike. In a dike with a core of sand a breach will develop faster than in a dike with a core of clay. Collect the research done to determine accurate ways of describing breach development. Can this research be expanded?
2. The different hydraulic models used for the flood scenarios (e.g. Delft-FLS and D-Hydro) have different methods to describe breach development. In both models, conservative estimates about the material in the core of the dike are made, leading to large inflows of water. What would the effect be on the safety standards if these assumptions were less conservative (if the actual material in the core of the dike is taken into account)?
3. If a dike was reinforced by adding clay to the core, this would affect flood simulations and the safety standards will be lower. Would this be an efficient dike reinforcement measure?
4. Are there other measures which can impact breach development that are effective in lowering flood risk? For example, adding roughness in the hinterland behind a breach would affect flow velocities through the breach and therefore breach development. Can the core of the dike be reinforcement with a creative measure to make use of the benefits of this?

We would like to do further research into the accuracy of breach development and the consequences of that on flood simulations and safety standards.

What you do as a Graduate Intern Fluvial Flooding Modelling

As different breach development formulas are used in modelling software, the first step of this research is to determine the ways in which breach development is modelled. This includes the models itself, but also other methods in literature. We want you to find the method(s) that corresponds to observations from experiments and compare that to the breach development formulas used in hydraulic models.

The second aspect is implementing the found dike breach development in the hydraulic model D-Hydro. D-Hydro has a standard breach development formula, so we need to find smart ways to adjust the resistance to match an actual breach. We would therefore like to challenge you to develop way(s) to properly model the breach development, without altering the breach development formula itself. For a student interested in soil mechanics the last two questions might be subject of the assignment too.

Where you will work

Royal HaskoningDHV is a worldwide independent engineering, project management, and consultancy firm which integrates 140 years of engineering expertise with digital technologies and software solutions. Our 6,000 colleagues are working from offices in more than 25 countries across the world. Through our mission “Enhancing Society Together”, we take responsibility for having a positive impact on the world.

You will become part of the team Resilience & Maritime the Netherlands. This team consists of around 230 colleagues and is based in the Netherlands across three offices (Rotterdam, Amersfoort, and Nijmegen). As a team, we excel in a wide variety of services and skills in the fields of climate resilience and maritime developments. We provide our clients, both private and (semi)governmental, with a range of services throughout the various phases of a project: from inception, through master planning, feasibility, design all the way to construction supervision. We have a strong foothold in the Netherlands, but we operate worldwide.

What you bring

You are a MSc student with educational track relevant to this topic, such as Civil Engineering. Besides that, you:

• are available to work full-time on your thesis
• have affinity with hydraulic modelling
• are proficient in both English and Dutch [because of the nature of this vacancy, Dutch language level (at least C1 is a requirement]
• are interested in working at a consultancy firm in the future

What we offer you

During your time at Royal HaskoningDHV, you will learn what it is like to work in a consultancy firm. More specifically, you will learn the kind of projects implemented by the advisory group Resilience & Maritime NL. You will be fully part of the team and as such, you are invited to participate in all team activities both project related and social activities. You will also receive a monthly allowance. You will be based in one of our Dutch offices, with direct support from our experts based in these offices.