Case Study Port of Hamburg/Germany
LOG_aLevel Storm Tide Network at the Port of Hamburg, Germany
Since 2003 a Storm Tide Network from General Acoustics GmbH (GA) has been satisfactory operating at the Port of Hamburg. In a first test phase of two years a LOG_aLevel station was successfully tested by the Hamburg Port Authority (HPA) against its conventional gauges. Due to the good results in terms of accuracy and robustness obtained with LOG_aLevel, HPA decided to set up a measuring network of stations from GA. In the current operational phase a Storm Tide Network consisting of four stations was installed and has been since then conveying data continuously.
The main objective of the network is to measure waves during storm at the second largest port in Europe. The port, located at the River Elbe about 100 km upstream from its mouth at the North Sea, is frequently affected by storm tides. The network was conceived to allow activation of continuous recording mode when a triggering event occurs. Under normal conditions all stations records tides by sampling data during 1 min every half an hour. In case of a storm they shift to continuous mode at a sample rate of 5 Hz, which allows to register every single wave. Due to the extreme narrow beam of its ultrasound sensors, which make this device unique, is possible to measure every single wave form.
The stations are laid-out to measure ranges up to 10m and transfer data remotely via GPRS to the control office of HPA. Different power supply options including, solar panels and wind generators are used. The station “Nienenstedt” is also provided with an external anemometer to measure wind speed and direction as well as air temperature. One possible event trigger is the occurrence of certain wind speed and direction measured by the anemometer and that can be specified by the user through the software (see bottom Figure). Another event trigger is a storm alarm on the website of the German Maritime Hydrographical Authority (BSH), which is being constantly monitored by LOG_aLevel Software. In addition to these triggers, the user can also manually shift to continuous mode at any time.