Author(s): Jiahao Zhang; Mengzhen Xu; Wei Liu; Lujie Han
Linked Author(s): Wei Liu
Keywords: No keywords
Abstract: Water transfer projects are constructed worldwide to alleviate the uneven distribution of water resources. Some of them face the risk of invasion and biofouling by mussels. Specifically, water transfer projects in Asia and South America risk biofouling by golden mussels, and water transfer projects in North America risk biofouling by zebra mussels. The East River Water Source Project (ERWSP) in Guangdong, China is a typical golden mussel-affected project. Mussels attach to the channel/tunnel walls with a density of up to 96000 individuals/m2, forming biofouling clusters and layers, increasing the wall roughness and flow resistance, and reducing the water conveyance capacity. Based on the relationship between mussel attachment density and hydraulic roughness obtained from a bespoke laboratory open-channel flow, a 1D model for the entire ERWSP was applied to study the effect of golden mussel biofouling on flow resistance. The hydraulic roughness denoted by ks of different sections was set according to the actual attachment densities observed during project maintenances. The model was calibrated with field data. Results show that high attachment density occured where the flow velocity was suitable for golden mussels. It is estimated that the head loss caused by the biofouling of golden mussels would increase by up to 25% every year. Therefore the prevention of golden mussel invasion would be crucial for the sustenance of water transfer projects and should be considered at the design and early implementation stages.