WESP

WESP ( W ater E n S trand P rofiler ) is a Dutch measuring vehicle for checking the underwater bed along the coast. The WESP is fifteen meters high and resembles a pyramid in shape . The vehicle drives in circular movements over the beach and up to eight meters deep water.

construction

The vehicle was developed as part of the KUST 2000 program by the Ministry of Transport and Water Management of the Province of North Holland in cooperation with the Rijkswaterstaat Rijksinstituut voor Kust en Zee (RIKZ). The design is based on the American Coastal Research Amphibious Buggy for short CRAB, a similar vehicle from the US Coastal and Hydraulics Laboratory .

It consists of a triangular basic structure of three 9.9 meter long steel girders at the corners of which the three wheels are arranged as well as three pyramid-shaped steel girders to which two platforms are attached. The upper platform at a height of 11 meters houses the driver's cab and the diesel engine with hydraulic pump attached below . This supplies the hydraulic motors of the three wheels. The wheels each have a diameter of 1.6 meters, the distance between the two rear wheels is 11 meters. To avoid the buoyancy of air-filled tires, they are filled with flexible polyurethane . The lower platform at eight meters serves as a work platform for underwater work and for lifting loads with the crane attached above.

The WESP is equipped with a DGPS-VPS and an IXSea Octans inertial navigation system for position determination, which determines the exact position of all three wheels.

commitment

An echo sounder scans the water level and the profile of the sea floor and the shore . The data are processed by geographers from the University of Utrecht . With the help of this data, they can calculate where, for example, a dike needs to be raised. Other areas of application include research into the ecosystem and maintenance work on the shaft measuring system near Petten .

Some parts of the Dutch coast are made of clay and peat , which is only covered with a thin layer of sand. If the sand layer has a hole at one point, the WESP with a wheel can get stuck in it. In one case, getting out of such a situation required the help of a floating crane and two bulldozers . For these cases, the WESP has special pulling points for attaching the ropes.

Since the vehicle is difficult to transport, it has so far only been able to be used in a very small stretch of coast. In 2003 the ministry therefore asked companies to find a way to transport the WESP over water. Such a floatable vehicle has not yet been built due to financial difficulties.

swell

BE Spelt, M. Rab, AH Kikkert: WESP: Water and Strand Profiler . In: Hydro International . tape 9 , no. June 5 , 2005 ( online ).