New Methods including Picture Processing for Hydro-Meteorological On-Line Data Acquisition

Early warning systems, quality control networks and sustainable protection of drinking water resources became more and more important as a main task of water resources management. They heavily rely on on-line measurements, which mostly are automated. Nevertheless the quality of the measured data can be increased by an integrated Quality Management System, including also the field measurement devices into a complete chain of quality traceability. To increase the data reliability alternative measuring methods have to be evaluated. In our prototype development staff gauge images are digitally processed to achieve a second value for the actual water-level. If the both detected water levels are different, an alarm is generated or remote configuration procedures are performed. The system is a contribution to an integrated Quality Management Tool, allowing retracing the complete chain of measuring value acquisition. Low Earth Orbit Satellites then allow worldwide “nomadic” on-line data-communication from otherwise inaccessible regions. Their combination with plausibility tests in the run-up to the database enables us to accept the great challenge of "real-time" supervision of the quality of the measurements. 1. Water Level Measurement System The gauge height is a most important parameter for hydrogeological investigations. Typical Measurement devices are differential pressure probes, pneumatic probes or radar devices, which require periodical control measurements. Usually this is realized by local service persons. In secluded areas, during wintertime or in vast regions, this can be impossible. Therefore we are developing a system to generate control measurements automatically from pictures of a staff gauge. System backbone is a near real time bidirectional LEO satellite communication link. From the measuring station (MS) in the field, periodical measurements of the water level (for instance with a pressure probe) and others, including quality parameters, are transmitted to a Central Monitoring Station (CMS) and after several plausibility tests, these values are stored in a data base (Figure 1). Additionally pictures of a staff gauge are shot. Image processing for automatically extraction of the water level is done in the camera. These control values are transmitted to the CMS. In a next step also the pictures will be transmitted via satellite to the CMS to retrace the whole procedure of water-level measurements and the integrated quality management system. Data from the MS is stored in a database as "original values" within the CMS. Plausibility tests can be conduced automatically. If several values are detected as "false value" (like spikes) a second quality level for "automatically corrected values" is created ("original values" are never changed or deleted). Both values are available for automated comparison. In case of deviations, different measures are possible: Alarm messages in the CMS, GSM based information to a local service team, a query to the system to verify the values, or a remote configuration of the MS. As the whole system works in "near-real-time", short response times are possible. 1 University of Applied Sciences FH Technikum Wien, Höchstädtplatz 5, A-1200 Wien, Tel.: (+43 1) 33 34 077; e-mails: christian.kollmitzer@technikum-wien.at; paul.skritek@technikum-wien.at; kurt.woletz@technikum-wien.at 2 Joanneum Research, Inst. of Water Resources Management – Hydrogeology and Geophysics, Elisabethstr. 16, A-8010 Graz, Tel.: (+43 316) 876 1326; e-mail: hermann.stadler@joanneum.at EnviroInfo 2007 (Warschau) Environmental Informatics and Systems Research Copyright © Shaker Verlag, Aachen 2007. ISBN: 978-3-8322-6397-3