Near Real-Time Quality Assurance of Hydrological Measurements using Failsafe Data Transfer

Abstract

Quality control (QC) of hydrological measurements also from remote measuring sites will be in the future a basic necessity in state of the art hydrological investigations. This will be of particular importance within quality assurance networks and early warning systems of drinking water supplies and all other tasks of sustainable water resource management. These systems heavily rely on on-line measurements and near real-time data transmission as well as automated plausibility tests in the run-up to the database in a Central Monitoring Station (CMS). To accept the great challenge of "real-time" verification of the quality of the measurements, which is very important for the supply of consumers with high quality uncontaminated drinking water, according to the European Water Framework Directive (European Parliament, 2000), we have established a bidirectional, dual wireless communication structure, combining GSM/GPRS data transfer with LEO-Satellite communication. In this way we obtain a failsafe data link from the spring in the remote area to the CMS. The data logger as the remote control unit manages the use of the two possible communication media. If available, the GSM/GPRS communication is used, otherwise the LEO-Satellite link is activated. This is necessary, because the small scale terrestrial communication structure of the cell-phone-networks are often impaired by local events like thunderstorms and floods. But especially during these times it is crucial to achieve information of the reaction of the spring. Therefore our system is a contribution to an integrated Quality Management Tool, which allows retracing the complete chain of generation of the measuring values.