Relying on the full-scale model test of embedded pile capping for Hong Kong-Zhuhai-Macao Bridge，the method
combining theoretical calculation analysis with in-situ monitoring tests is used to study the over-dredged depth of foundation
excavation. In the theoretical calculation estimate，an empirical formula of the Hydrology of Sea-port is adopted for the overdredged
depth, while the single-beam is for the topographic survey underwater at random after the foundation excavation in the
in-situ monitoring test. On that basis，proper over-dredged depth of pile cap foundation excavation is put forward to provide
key construction parameters for the main works of Hong Kong-Zhuhai-Macao Bridge.