Abstract
While sediment is needed to build aquatic habitats and reintroduce nutrients for submerged vegetation, too much sediment can easily cause ecosystem and safety issues. Sediment buildup can damage the drainage ability or navigability. In addition to the problems cause by load quantity, sediment can easily introduce pollution and other contaminants into a waterway, spreading the pollutants downstream1. As contaminants do not degrade (or degrade very slowly), they can be a source of environmental issues for long periods of time, even if they are not frequently resuspended. The most problematic contaminants in both bedded and suspended sediment are metals and persistent bioaccumulative toxics (PBTs), such as pesticides and methyl mercury2. Sediment remediation may involve dredging to remove the deposited and contaminated sediment from the waterway1. The dredging method has some disadvantage points like it costs a lot of money or it cannot be used in urgent cases, therefore a new method which can encounter those disadvantages should be developed. A new tool, which named “Bamboo Spike Ball” or “BSB”, is invented with the hope that it can remove sediment in a cheaper cost and can be used in urgent cases. BSB basically is designed by using stone, clay and bamboo which are cheap and eco-friendly materials. Bamboo spikes are tied surrounding stone in a sphere shape so that BSB can roll along the channel by flow force effect. PIV technique was used to figure out the effect of BSB to erosion characteristic on bed. The result showed that while BSB was rolling, under the effect of the collision force of BSB's spike and turbulent flow caused by BSB's structure, significant amount of sediment was removed in compare with case which river bed is affected by flow only.
