Samen Sterk/Stronger Together aims to enhance flood protection in the Dutch lower rivers area threatened by rising sea levels. The key innovation is the addition of the Holland Barrier alongside the existing Maeslant Barrier, rather than replacing it as per current policy. This dual barrier system significantly reduces the risk of failure, lowers water levels, improves water management on the south side, and allows for continuous barrier operation during maintenance. This approach saves costs on dike improvements, maintains vital sea connections for shipping and ecology, and promotes future waterfront development, including unembanked port industry, offices, housing, and more.
During high flows events, debris (e.g. driftwood, plastic, rubble, etc.) are likely to accumulate at riverine bridge piers. Recent research has acknowledged the negative consequences of debris accumulations at bridge piers on bridge stability, hydraulic capacity and therefore on inundation dynamics. More specifically, the accumulated debris may causes an increase of the water velocity, with consequences on hydrodynamic phenomena (e.g. scour); moreover, the clogging also causes backwater level rise, with consequences on the surroundings (e.g. embankment failures, overflow). During the 2021 floods in Belgium, Germany and Netherlands, many bridges suffered from debris accumulation. Currently, satellite imagery have been shown to capture debris accumulation (e.g. Panici et al., 2020) in given locations and for several years, but this technology has not been explored yet.
When designing hydraulic structures, foundations (or parts of) are located in open channels (like bridge piers) or in the sea (like offshore wind foundations). The structures influence the motion of the water around them, and in combination with erodible beds, the resulting sediment transport gradients could lead to local erosion (scour) around the base of the foundation. Scour can lead to structural failure and needs to be managed. Knowing the depth, extent and time development of scour holes at the base of foundations is crucial for the design of the foundation: the information can be used to determine if extending the foundation depth is a viable option, or if designing a scour protection is a more cost-efficient option. Assessing scour hole development is, in general, not a trivial task. Especially for milder conditions, where the external forcing does not often exceed the threshold of motion, we often see a huge bandwidth of possible scour depths with current approaches, likely related to uncertainty in the threshold of motion of sand, in combination with the threshold of scour development around a structure. Uncertainty related to natural variation of the alluvial bed, fluctuation in conditions and simply uncertainty in scour assessment methods further adds up to the great variation in assessing scour depths.
In recent years, the concept of Digital Twins has gained remarkable traction across various sectors, revolutionizing how we understand and manage natural and human (complex) systems. A Digital Twin is a virtual representation of a physical entity, with a typical “twinning” connection where real-world data inform the virtual model, and vice versa outputs from the virtual model inform decisions in the real world. One of the areas where this technology holds immense potential is Civil engineering, and in particular catchment management. By developing a Digital Twin for catchments, we can gain valuable insights into the hydrological and ecological dynamics, leading to more informed decisions and practices around flood management, water resources, water quality and beyond.
The Netherlands is a front runner in the field of hydraulic engineering. The design of our dikes, locks, sluices and barriers can be considered as the most advanced worldwide. The department of Hydraulic and Ecological Engineering of Rijkswaterstaat deals with the preparation and supervision of complex infrastructural projects and programmes nationwide. Large projects such as the redevelopment of Meuse river (Maaswerken), Lock improvement program and the renovation of the Afsluitdijk are some examples.
In the Netherlands, historically much has been invested in flood prevention. However, there has been little focus on preparation before and during a flood. Without plans for preparedness and emergency management, floods can extensively disrupt the regular functioning of the healthcare system. The floods in the Netherlands, Germany and Belgium in July 2021 revealed what the consequences could be, and that we need to better prepare healthcare facilities, even during a shortlived flood. For example, the VieCurie Medical Centre in Venlo had to evacuate more than 200 patients due to an anticipated flood threat, whereas some elderly homes were flooded and evacuation of their vulnerable patients completed although flooded. This experience indicates the potential lack of awareness and preparedness of healthcare facilities to flood risk.
Celebration of the end of the exam period of Q3 with HE & HOS students! Come join us at Café de V from 17:00 until 20:00 for some free drinks and snacks!!
A lunch lecture by MTBS with free lunch! 🙂
More information TBA
A case day at the office of Horvat & Partners in Delft. More information and registration TBA.
In 2008, hurricane Ike caused 38 billion US$ worth of damages, among much of that in the greater Galveston & Houston areas in Texas, USA. The area in general is immensely vulnerable to storm surge from a hurricane, which could push a wave of water into homes on Galveston Island and up the Houston Ship Channel, dislodging chemical tanks and damaging refineries. In response to that, the US Army Corps of Engineers has begun planning for a massive 31 billion US$ coastal barrier project in Galveston Bay, formerly known as the “Ike
dike”. The project has recently been approved by US congress and is now moving forward towards engineering works quickly. Among others, the project consists of around 90 miles of coastal protection and several storm surge barriers crossing the Galveston Bay inlet, thus protecting Galveston island and the Galveston Bay from surge during hurricanes. These storm surge barriers will consist of many vertical lift gate barriers and two large navigable sector gate barriers to allow shipping to freely pass during daily circumstances. More information on the project can be found on the official website.
For this master thesis, we are looking for an enthusiastic student in hydraulic engineering with a specialization in hydraulic structures, who will be looking into the design of these sector gate barriers. During hurricane conditions, the water first will be pushed into bay and thus into the storm surge barrier. However, as the hurricane passes, the wind direction will change, and water will be pushed out. As it is unlikely the sector gates will open during hurricane conditions, this will generate a reverse head on the storm surge barrier and thus back pressure.
How can a sector gate barrier be designed in such a way that it can withstand these pressures? What alternative types of storm surge are possible that can withstand all loads, while still allowing navigability? How will this barrier look and fit in? These are all questions that are very open and are in need of well substantiated answers.
If you are interested in this vacancy, send an e-mail to Maarten Schoemaker (firstname.lastname@example.org) or Ric Huting (email@example.com).