Delta Life 12

DELTARES, OCTOBER 2019 3 DELTARES IN BRIEF MOZAMBIQUE USES COASTAL FORECASTING SYSTEM Cyclone Idai battered Mozambique on 15 March 2019. As a result, the coastal city of Beira was ninety percent flooded, in some places up to six metres deep and half a million people living in and around the city were displaced. Deltares had already developed a national coastal forecasting system for five coastal cities – including Beira – in collaboration with the INAM meteo­ rological institute. The main purpose of this model was to provide port opera­ tors and fishermen with local detailed forecasts. When Idai came ashore, the system was used by the authorities to warn residents about the cyclone. Even after the cyclone had passed, Deltares still used forecast models to estimate rainfall, water levels and possible risks for dams. These data helped rescue missions to do their work. MORE RELIABLE CABLES FOR OFFSHOREWIND TURBINES Failing power cables at sea are one of the main risks for the development and operation of offshore wind farms. Approximately eighty percent of insurance claims in the offshore wind industry relate to cable outages. To reduce the number of outages, more than thirty international organisations have launched a joint research project: the Joint Industry Project CAbles Life­ time Monitoring (JIP-CALM). During the two and a half year project, the researchers will seek to identify possible improvements in all the phases of the life cycle of submarine power cables. Reducing the risk of submarine cable failures makes the offshore energy grid more reliable and establishes a clearer picture of the total cost of using offshore cables. T he first genuine land-subsidence monitoring site in the Netherlands has been established in the peat-rich area of Overijssel to monitor land subsidence in space and time. Four different measuring techniques – surveying, extensometers, LiDAR and InSAR – will be used to monitor land subsidence for at least five years. The site is the first step on the road to a national monitoring network for the structural and frequent measurement of subsidence. The monitoring of subsidence in a complete area helps to determine the effectiveness of measures to combat subsidence such as under­ water drainage. It also provides a picture of how fast subsidence is, and how it varies in an area and over a year. The measurements can then be used to unravel the mysteries of the processes that lead to land subsidence. Effective technical and policy measures can be developed only if we knowwhich proces- ses cause subsidence. UNIQUE LAND-SUBSIDENCE MONITORING SITE IN THE NETHERLANDS GOES OPERATIONAL