'Smart levees' predict breaks 42 hours in advance

Dutch engineers can predict 42 hours in advance whether levees will break, using a 'smart' network of sensors, monitored from afar by computers. A series of tests was carried out by the Dutch Water Affairs Ministry on a 6m-high, 100-m long earthen dam.

The Dutch have already started calling them Digi-Dikes. see The leading project engineer said their scientific aims for trying out such a 'smart-levee' system are two-fold: first, to develop multi-sensor networks and IT-tools for them, and to increase the knowledge of Dutch water-barrier engineers as to exactly why and when such 'water-retaining structures' would start to fail - before the water has a chance to pour through. see The tests are carried out by the IJkdijk foundation - pulled together from group of institutes which all focus on the development of knowledge in the field of Delta- and sensor technology. Since August last year, they have been carrying out a series of experiments to test whether and how their new multi-sensor networks and IT-tools could supplement the standard visual inspections carried out by the country's network of levee-patrollers and dike-managers. What the Dutch were particularly interested in -- besides learning to set up these smart-levees efficiently -- was whether any deviations in the dam-systems could be found in enough time to allow water authorities to take timely, i.e. emergency measures to start fixing the levees, and also to give authorities enough time to evacuate an affected community. New Orleans:These smart levees would obviously be of particular interest to low-lying areas such as New Orleans in the United States, Bangladesh and the wetlands regions of the United Kingdom which all are at risk of potential flooding, the IJkdijk Foundation spokesman said. "There is the realisation that not only can potential flooding risks be prevented by stronger levees, but also by using advanced prediction systems in a preventative way to manage and combat disasters', he said. The team publishes its comprehensive report on exactly how they built their smart dike next week. The Dutch engineers are hoping that by installing such sensoring networks, they could predict and hopefully even prevent two recent dike-breaks in The Netherlands in August 2003 and January 2004. About one-thirds of The Netherlands lies below sea-level, some places as deep as 6 meters below, mostly in the most populated and also agriculturally and economically most important areas. Any breaks in the huge Dutch network of dikes and dams would be a major disaster, not only for the Dutch, but also for the European hinterland which greatly relies on the Dutch harbour systems for the import and export of their commodities. This so-called 'macro-stability experiment' was carried out in a series of controlled collapses since 5 August. The precision job, carried out by a highly-skilled team of Dutch water-barrier engineers and top experts in their field, was a precise, hands-on learning experience, they said. They constructed a 100-meter-long dam with layers of gravel, clay, sand and grass around their carefully laid-out network of electronic sensors. They then installed large pads on top and on the sides which could apply pressure at any given portion of the dike. The project manager of this test team was Ton Peters. see They then started forcing controlled breaks in the earthen dike and were able to forecast 42 hours in advance on their monitors, fed by the network of sensors, exactly when the dam would start collapsing. The pressure applied was similar to wave motions at specific storm levels. see The next step for the IJkdijk Foundation will be a larger pilot study, in which a 600-meter 'smart-levee' will be created at the Eems-harbour in Groningen, in the northern-most province of The Netherlands. see