ABSTRACT
This chapter covers the measurement of stage, discharge and the determination of rating curves, and methods for direct measurement of stage. Stage is usually either used as an index for discharge estimation, or to give levels in reservoirs. Although the fundamental measurement techniques are the same in both cases, the practical considerations are usually different, and the demands on the installations and operation procedures differ. Non-recording gauges are labour intensive, unsuitable in uninhabitated areas, and give inadequate time resolution in streams with rapid variation in stage. The solution to this is to use recording gauges. High precision mechanical instruments such as stage recorders are becoming increasingly expensive, while prices on electronic equipment are falling. Correction for the influence of ice must be based on discharge measurements during winter.
