1. They built timber groynes and constructed chalk banks and patched up breaches as they occurred.

2. The contribution of groyne height reduction to counteracting unwanted erosion is then considered a favourable incidental circumstance.

3. Thomas decided that the solution was a rounded end to the groyne.

4. A formula reflecting the stabilization of riprap in a closure work and of groyne head apron is thus deduced.

5. Experimental study includes the law of flow field variation and variation of water surface in affected zone by the single groyne or twin-groyne.

6. This paper studies on the law of the kinetic energy correction factor near a groyne by a flume experiment basing on one dimensional energy equation of steady flow.