A detailed review and chronological survey is presented of the various techniques which have been used for the measurement of river bank erosion and channel change. The techniques are classified according to the time scales involved (long, intermediate and short) and each is discussed with respect to accuracy and repeatability. The methods covered include sedimentological evidence, botanical evidence, historical sources, planimetric resurvey, repeated cross-profiling, erosion pins and terrestrial photogrammetry. Prospects for future developments are also discussed.

The measurement of river bank erosion and lateral channel change: A review

Erosion of streambanks and shorelines by exfiltrating seepage is called sapping or piping (because tubular cavities are produced). This mechanism is widespread in occurrence and is very significant to bank and shore stability, but is rarely recognized. The mechanism is complex and acts in concert with other processes of bank and shore erosion and deposition. Operation of those other mechanisms often masks the processes and products of the piping/sapping mechanism. Furthermore, failures caused by this mechanism may occur during periods of stream inactivity long after storm and/or flood events have ended. This paper describes and illustrates characteristic features of piping/sapping erosion and attendant instability. Situations typical of sites where piping/sapping is significant are illustrated. Conditions necessary (but not necessarily sufficient) to cause piping/sapping are presented. Diagnostic procedures are presented in a companion paper. The purpose of this paper is to present the fundamental aspects...

Piping/Sapping Erosion. I: Basic Considerations

Row-crop agriculture, continuous-grazing, and stream channelization, have accelerated stream bank erosion and increased sediment load. Stream bank erosion rates and total soil loss were compared among riparian forest buffers, row-crop fields and continuously grazed pastures along a continuous 11 km (6.8 mi) stream reach in central Iowa. Exposed erosion pins were measured to estimate stream bank erosion rates, approximately every month from June 1998 to June 1999, except during the winter months. Total stream bank soil losses for each treatment were estimated from the mean bank erosion rate, mean bulk density, and the total stream bank eroding area. Row-crop fields had the greatest stream bank erosion rate and total soil losses followed by continuously grazed pastures while riparian forest buffers had the lowest. If riparian forest buffers had been established along all of the non-buffered segments of the 11 km (6.8 mi) stream reach, total stream bank soil loss would have been reduced by approximately 72%.

Stream bank erosion adjacent to riparian forest buffers, row-crop fields, and continuously-grazed pastures along Bear Creek in central Iowa

Needle ice processes and sediment mobilization on river banks: the River Ilston, West Glamorgan, UK

One of the major tasks in earthquake geotechnical engineering is the preparation of liquefaction susceptibility maps. For this purpose, some indices associated with liquefaction susceptibility are used. However, the currently used indices have some limitations. In this study, a liquefaction severity index, which can be used in preparation of susceptibility maps, is suggested. The suggested severity index is applied to two sites selected from Taiwan (Yuanlin) and Turkey (Inegol) to examine performance. The application indicated that the suggested index shows a good performance for the selected sites, and can be considered as a tool for further studies.

M.F. Spoor

Papers

Bank failure and erosion on the Ohio river