ABSTRACT
This chapter describes instrumentation and methods to collect data on topography, bathymetry, and bed roughness. It also describes the development of the instruments mainly driven by disciplines other than hydraulic engineering such as physics, geodesy, construction, or by industrial applications. The chapter deals with regard to the measurement of topography and bathymetry from larger to smaller spatial scales and hence also from 2.5D to 1D measurements. It focuses on traditional sieve-analysis and an advanced optical method to get automated information about bed surface grain-size distributions. Ultrasonic transducers are devices that convert ultrasound waves to electrical signals, as well as the reverse. In hydraulic engineering, active and passive devices are used for flow velocity measurements, sediment transport measurements, discharge measurements, and remote sensing to determine water depth and to scan underwater topography. Standard survey equipment is commonly used to obtain information about topography and bathymetry.
