Flume studies often seek to measure and record the interstitial flow within plane-bed sediment bodies and within sediment beds with wavy surfaces, such as those typified by salmonid fish spawning nests and river-dunes. A simple, inexpensive method is described to record and map, at discrete points, the spatial variation in interstitial flow speeds in experimental fine gravel beds. The procedure uses activated carbon granules to capture a tracer: Rhodamine WT dye. Calibration of the uptake of dye by the carbon for known interstitial flow speeds allows mapping of point flow speed data initially in the nominal x-dimension. Using interpolation procedures available in a range of commercial 'mapping' software packages, the point data can be used to produce quasi two-dimensional 'slices' along sampling planes within the three-dimensional gravel bed. Similarly, three-dimensional representations can be produced within which lines of equal current speed ('isovels') are interpolated such that the flow vectors (in x, y and z coordinates) may be inferred.

A refinement to the conductiometric standpipe method for determining interstitial flow velocities is described. Three modifications to the original calibration are presented: (i) development of calibration curves for gravels of varying permeability; (ii) statistical validation of a practicable field run time; and (iii) integration of zero velocity flow data to the calibration procedure. These modifications are shown to improve the conductiometric probe's ability to delineate interstitial flow velocities considered critical to salmonid incubation success. Field deployment of the probe highlighted its practical application for determining interstitial flow velocities in salmonid spawning gravels.

Many coastal areas throughout the world are suffering from erosion, so numerous attempts are made, by constructing various forms of sea defences, to stabilize a retreating beach or reduce its rate of erosion. In recent years, artificial beach replenishment has become an established method in helping to restore a deteriorating beach. However, there has been a relative lack of information regarding the post-replenishment behaviour of many artificially renourished beaches. Results of a study of a replenished beach at Hayling Island suggest that the apparent depositional and erosional trends measured along a typical beach profile can be due to the longshore movement of a single, trapezium-shaped, mass of shingle, at a constant rate, rather than variations in the longshore transport rate.

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