The estuaries of the Port Davey-Bathurst Harbour area, including Melaleuca Inlet and Creek and the Davey, Spring, North and Old Rivers, are Holocene sedimentary basins. The once depositional banks of all these estuaries are now eroding. Due to concern that wave wake was the cause of the erosion (like on the lower Gordon River) a monitoring program was first established in Melaleuca Inlet and Creek in 1992 and expanded to the other estuaries in 1997. That monitoring program is documented in the following reports:-