The estuary's main central basin connects with smaller sub-basins, such as Orielton Lagoon and Iron Creek Bay, and is shaped by a combination of tidal flows and sediment dynamics.

By the mid-19th century, the area had developed into a hub for farming and fishing, with its fertile soils supporting agricultural activities, particularly cropping and grazing.

The site supports a diverse range of flora and fauna, including many migratory bird species protected under international agreements such as the JAMBA and CAMBA.

Key species that inhabit the area include: Saltmarsh habitats around Pitt Water are also vital for carbon sequestration, nutrient cycling, and buffering against coastal erosion.

The main channel, about 12 km long with an average depth of 8 m, facilitates water exchange and stabilises salinity, temperature, and nutrient levels.