The hydrological,geographical and geological conditions along the Qiantang estuary are very complicated, especially the character of the strong tide bore is an outstanding difference from the ordinary tide and flood.

• 钱塘江河口沿线的水文、地形、地质条件十分复杂,强涌潮的存在及其完全不同于洪、潮水的特性,恶化了施工条件,增加了海塘建设的复杂性和难度。