Coasts & Seas

Burial depth study Borssele

Client: Tennet TSO.

In front of the coast of the province of Zeeland, the Borssele wind farm is under construction. The subsea power cables connecting the wind farm zones to the electricity grid on land have to be buried into the seabed to protect them against external threats. However, due to migrating sandbars, sandwaves and bar-channel systems, the seabed along the cable route is mobile, leading to a change in burial depth through time. The main objective of this morphological study is to quantify the optimal burial depth, such that the total costs (installation costs + required maintenance) during the entire lifespan of the power cables are as low as possible. The study shows that the Spijkerplaat, a very morphological active sand bank,  has a large effect on the maintenance requirements and optimal installation depth.



Sand waves at km 54-55 of the cable track

Coastline study Lagos, Nigeria

Client: Dredging International.

At the port of Lagos (Nigeria), a breakwater is build into the sea. This requires a large amount of sediment, which is dredged in close proximity and then deposited at the location of the breakwater. However, severe coastal erosion occurs in the vicinity of the dredging activities. During this study, the offshore wave climate has been translated to the coast and the alongshore and cross-shore sand transports were determined. The objective of this study is to investigate whether the coastal erosion is related to the dredging activities.

Significant wave height in the study area during the year 2013

Development wave buoy

In order to obtain actual wave data, we are currently developing a practical wave buoy in collaboration with Jato Cleanroom Supplies. The wave buoy will provide data on wave height, wave period and wave direction. Thanks to the different communication modules, the real-time data can be read from the buoy. Due to the convenient size it will be relatively easy to deploy this buoy temporarily, for example during during storms, and retrieve it afterwards. The buoy will be equipped with solar panels for long-lasting measurement campaigns (lasting over one year). The practical size means there is no need for a large vessel with heavy crane, basically a small boat with two surveyors is sufficient to deploy the buoy.

The prototype measuring during a sunset at sea

Optimization salt marsh design Terschelling

Client: Provincie Friesland.

In 2015, a preliminary design was released for developing approximately 88 hectares of salt marsh on the south side of the Wadden island of Terschelling. This preliminary design was optimized by WaterProof from a hydromorphological perspective. This was done by analyzing the present and historic hydromorphological situation of the area by means of data analysis and a small field campaign, studying the best type and location of salt marsh screens and modelling the effects of several alternative designs in order to find the layout in which the salt marsh will develop the quickest. The study shows that salt marsh development at this location will be slow but can be stimulated by implementing an alternative design. The effects on the nearby environment appear to be limited, but it is recommended to carry out a thorough monitoring program before and after construction.


The present situation at the proposed salt marsh location

Reducing silt sedimentation Noordpolderzijl

Client: Municipality of Eemsmond.

The port of Noordpolderzijl is located in the municipality of Eemsmond, situated at the Wadden Sea coast. In recent years, the port is silting up rapidly and becomes increasingly difficult to access by boat. This study investigates whether low-cost options are available to reduce the silting up of the harbour and navigation channel of Noordpolderzijl. An important part of the study will be devoted to investigating whether the creation of an artificial basin can contribute to this. The first phase of the project mainly focuses on hydrodynamics. By means of data collection, limited field measurements and a first exploration with numerical models it is being investigated whether construction of an artificial basin can influence the water motion in such a way that sediment can be transported out of the channel towards the Wadden Sea.


Impression of the channel near the harbour

Ports & Infrastructure

Morphological study deepening New Waterway Rotterdam

Client: Port of Rotterdam / Arcadis

The coming years, the Port of Rotterdam will invest a significant amount of money in revitalization of existing port areas. One of these areas is the Botlek/Vondelingenplaat, where the Port Authority will improve nautical accessibility by deepening. The dredging volumes that are a result of this are significantly larger than the threshold for EIA requirement. For the purpose of preparing the EIA, a morphological study was conducted. This study investigates the effects of the proposed deepening on the channel morphology.


Computational grid of the Delft3D model used in this study

Optimization dredging strategy deepening New Waterway, Rotterdam

Client: Port of Rotterdam

The coming years, the Port of Rotterdam will invest a significant amount of money in deepening of the Nieuwe Waterweg and the Botlek/Petroleum harbours. During the execution of the dredging activities, additional turbidity will be generated and hence an increase in sedimentation will occur. By cleverly combining dredging and spreading, the required dredging volumes can be minimized and thus the environmental effects and related costs can be limited. This study provides advice on the most clever dredging strategy, to ensure that the final volumes to be dredged are as small as possible.

Deepening locations in the New Waterway

Wave penetration marina Cadzand

Client: Infra Trading/Walcon Marine.

The Cadzand marina is planned in the outlet channel west of the town of Cadzand, Zeeuws Vlaanderen, the Netherlands. To facilitate mooring of small yachts and vessels, a set of floating pontoons inside the marina is foreseen. These pontoons are only feasible to position if they can withstand the operational and extreme wave conditions inside the marina. This study (in cooperation with Van Vledder Consulting) investigates whether the wave conditions within the marina are sufficiently low that during operational and extreme situations only limited damage occurs to the pontoons and moored vessels.

Variation in signification wave height for layout 1

Nautical feasibility bridge Urk Channel

Client: Municipality of Urk.

South of the 'Polderwijk' district in Urk, a bicycle bridge crosses the Urk Channel. Due to development of the area south of the Urk Channel, there is a need for a bridge that can be used by cars. The proposed location of the new bridge is located in a bend of the Urk Channel in such a way that it achieves the most direct connection between the existing infrastructure and the new district. This study examines whether the proposed location is possible from a nautical point of view.

Overview of the proposed new situation

Reinforcement Houtribdijk

Client: Jan De Nul Group.

The Houtribdijk is a dike located between Enkhuizen and Lelystad and forms a barrier between the Markermeer and the IJsselmeer. The so-called 'dike-MOT' showed that the Houtribdijk no longer meets the legal safety standards as set in the Water Act. Therefore, reinforcement of the Houtribdijk is necessary. The main part of this reinforcement is to add a prescribed sand nourishment on both sides of the dike to better protect it against severe storms. In this study, WaterProof calculated in detail the required sand and rubble stone volumes for the Houtribdijk project. This was done by creating a 3D model of the current Houtribdijk and the proposed sand nourishments, and then add this 3D model on top of the present lake bed. A first draft design of the Trintelzand nature reserve is also included in these calculations.


Aerial photograph of the Houtribdijk

Reinforcement Prins Hendrikdijk

Client: Jan De Nul Group.

The Prins Hendrikdijk is a dike located at the south-eastern coast of the island of Texel. In 2006, it turned out that this dike did not meet the safety standards as set in the Water Act. Therefore, reinforcement of the Prins Hendrikdijk is necessary. It has been decided to apply an outer dike reinforcement, which combines high water security with nature development. The plan foresees the outer dike construction of a safety dune, a spit with sand rich of shells and a few dynamic lagoons. In this study, WaterProof made a major contribution to the necessary ‘Plan Sand extraction and processing’. This included a detailed analysis of the sand extraction area on the basis of available data (cores, bottom depth, object locations) and determining the available and required sand volumes for this reinforcement.

AI Prins Hendrikzanddijk
Impression of the final situation

Marine Ecology

Feasibility study Eelgrass Seed nursery

Funder: Netherlands Enterprise Agency

WaterProof BV. has been awarded with an MIT-subsidy for carrying out a feasibility study for the founding of the Eelgrass Seed nursery®. The cultivation of eelgrass seed will eventually lead to an enrichment of our coastal ecosystems, where the earlier seagrass areas unfortunately have disappeared due to various factors. The product can be exported and used worldwide for eelgrass field construction and restoration projects. Pilot experiments were carried out in collaboration with Tjisse van de Heide and the Fieldwork Company, with the aim of investigating the technical aspects. In addition, the economic aspects, social support and applicable laws and regulations have been studied. The concept was represented to potential stakeholders who’s first responds was positive. The feasibility report can be downloaded here.


Experimental setup Eelgrass Seed nursery®

Support future vision on Eelgrass in the Dutch Wadden Sea

Client: Program for a Rich Wadden Sea.

Eelgrass fields make the water clearer and provide a breeding ground for many fish species. In terms of policy the restoration of eelgrass habitat is important for the realization of the set objectives in the Water Framework Directive and the Habitat and Bird Directives. Managers, researchers and policy makers have been working for years to get eelgrass back in the Dutch Wadden Sea. Hereby it is necessary to align current and future efforts well with each other. Therefore, the document 'Future Vision Eelgrass' has been written, which describes the vision for the approach to build up knowledge in order to restore in an effective way eelgrass fields in the Dutch Wadden Sea.


Seagrass at the sea bed

Technical support radar systems offshore wind farms

Client: Rijkswaterstaat Sea and Delta.

In periods where many birds migrate over sea, the amount of birds that collides with rotor blades of offshore wind turbines increases. To limit the effects, a mitigation measure is imposed in which the turbines rotate very slowly during bird migration periods. This measure requires insight into the intensity of bird migration (flux). This can be achieved by the use of radar systems and models. In this study, the various radar systems are identified and the feasibility of setting up these systems on offshore wind turbines is investigated. In addition, bird radar specialists and model developers were asked how to collect the appropriate information for implementing the measure and for model validation. The final report (in Dutch) can be downloaded here.


Overview of a radar system

Biofouling marine cables, Germany

Client: CPNL Engineering.

Currently, the Innogy Nordsee 1 Offshore Windfarm is under construction in the German Bight. CPNL Engineering provides a cable protection system for the cables between seafloor and turbine entrance. Usually, the cables quickly overgrow with organisms, also known as biofouling. For offshore constructions in general, a biofouling layer thickness of 100 mm is assumed, but it is questioned whether this thickness also applies to the Innogy Windfarm cables which have high operating temperatures between 70 – 90 °C. Therefore, CPNL Engineering requested WaterProof BV to assess the expected biofouling on the protection system of the cables of the Innogy Nordsee Windfarm.

CPNL cable protection system

Ecological support for container terminal Flevokust, Lelystad

Client: A&W.

WaterProof B.V. has contributed in this study to exploring ecological opportunities in the planning area of the container terminal Flevokust. Here, the focus is on development measures with positive effects on birds with conservation objectives for the Natura 200 area IJsselmeer. Think for example of shell or gravel layer on the breakwater, reefballs for the breakwater, Elastocoast on collapsed stone banks, extension of the breakwater or silting of parts of the port. These measures can be used in the further development of the container terminal Flevokust.

Common tern on a floating platform

Potential effects of elektromagnetic fields in the Dutch North Sea

Client: Rijkswaterstaat Water, Traffic and Environment.

A strong development of offshore wind farms in the Dutch coastal zone is foreseen in the coming years. These offshore wind farms will be connected to land by subsea power cables that transport the generated energy to shore. These cables generate electromagnetic fields (EMFs) and induced electric fields (iEFs) in the marine environment, the impact of which on the marine ecosystem is largely unknown. To close this gap, WaterProof has started a research project to investigate the effects of electromagnetic fields on the marine environment. This project consists of two distinct parts. The first part comprises a desk study about electromagnetic fields in general and the known effects of electromagnetic fields on marine life and the second part explores the opportunities for designing an experimental setup to study the effects in water basins or in the North Sea.


Measured geomagnetic field intensities (NOAA, 2014)

Specifications radar systems offshore wind farms

Client: Rijkswaterstaat Sea and Delta.

In periods where many birds migrate over sea, the number that collides with the rotor blades of offshore wind turbines increases. To reduce the number of collisions, a measure is inflicted in which the turbines will be temporarily shut down during migration periods. In the spring of 2016, WaterProof conducted a technical assessment of suitable radar systems in which the specifications were discussed with various stakeholders. Based on this information, a first move was made towards the installation of radar systems at different wind farms. The objective of this follow-up study is to determine together with stakeholders the functional requirements of the radar systems and describe these in accordance with the CIV contract system, so that based on this a European tender can be set in the market.


Overview of the study

Underwater Acoustics

Measurements during removal of old windmills, Medemblik

Client: Deep B.V.

In front of the Coast of Medemblik (located at the lake IJssel), a total of four old windmills were removed in October 2016 because it was no longer profitable to exploit hem. To remove the windmill foundations, a vibratory technology was used. During the vibration periods, WaterProof B.V. conducted measurements with multiple recorders at different distances from the vibration source. The purpose of these measurements is to map the amount of noise that is caused by such offshore activities and to find ways to reduce the noise level in the future. This way, it is possible to comply with set regulations by various countries. See also this flyer for an impression.


The vibration equipment used to remove the wind turbine foundations