Continuous Suspended Load Sampler

Knowledge of the response of sediment particles to the hydraulic forces produced by shoaling waves is essential in studies of both large and small scale sedimentation patterns along sandy coasts. While accurate fluid-flow measurements are possible in even the most energetic nearshore waters because of technological advances in commercially available current meters, the technology for measuring sediment response is far less satisfactory (Downing, 1978). Direct samplers such as pumps (Watts, 1953; Fairchild, 1973) and water corers (Kana, 1979; Inman et al., 1980) can provide accurate data but are limited by spatial and temporal resolution. Optical instruments previously used (Brenninkmeyer, 1974, 1976) had excellent frequency response but lacked dynamic range; they also were subject to interference from gas bubbles entrained by breaking waves. In order to integrate sediment dynamics studies into the surf zone dynamics aspects of NSTS, it was necessary, therefore, to design and develop new instrumentation to measure the spatial and temporal characteristics of the suspended sediment concentration field.