Conceptions nouvelles en matière de mesures limnimétriques sur les cours d'eau

Chef du Département Recherche Appliquée du Service Hydrologique de l'O.R.S.T.O.M.

Résumé

The running of a hydrometric network is discussed within its theoretical setting under such varied aspects as the measurement of stage/discharge data, their collection of transmission, conversion of 'stage' data into 'discharge' data, processing and publishing the latter, and general data classification and filing. The French Ministry of Agriculture's aims and purposes are discussed with regard to the requirements of its gauging network ; optimal features of stage measurement equipment or 'level recorders are prominent among the points explained. A complete list of stage recording equipment available on the market is subjected to a critical analysis with a view to ascertaining whether it meets present gauging network requirements, and it is found that there are several gaps requiring new types of equipment. At least three European firms have produced prototypes (Neyrpic and S.F.I.M.) or modified an existing level recorder (Ott, type 20 060). All this new equipment is under test at the time of writing. The author gives some additional information on the prototype equipment, i.e. the Neyrpic pneumatic remote-reading level recorder and the S.F.I.M. strain gauge pressure pick-up recorder. Both manufacturers are considering an I.B.M. tape code print-out system enabling visual data-processing. The article ends with discussion of the main lines along which a complete control 'sequence' for a gauging system might run, in theory, allowing for data-processing requirements. Five such sequences are presented in detail, being both suitable for the French Ministry of Agriculture's requirements and feasible with present available standard or prototype equipment.