Unification Of Elevation Datum For Water Resource Management In A River Basin

Abstract

In the water resource management of a river basin, elevation values used in various calculations, hydraulic analysis, river building planning, flood control, irrigation planning and others must refer to the same elevation datum. The most suitable elevation datum in the water resource management of a river basin is geoid, and the most suitable elevation system is orthometric elevation system. The unification of elevation datum consists of the determination of its point origin, tide observation, and the installation of elevation datum network. The point origin is a permanent peg called peil installed next to the location of sea surface tide observation.Minimum tide observation is 29 days. Elevation datum network is a benchmark, installed systemically along the left and the right sides of the main river, tributary,around the irrigation development area, dam plan location, and others. The calculation of the height difference between benchmarks is conducted using precise levelling method.