Estuarine canal estates are man-made canals that are connected to estuaries and therefore have tidal influence. The canals are usually dug into unconsolidated sedimentary aquifers including coastal sand masses (see coastal sand masses – beach ridges) or alluvia deposited during periods of higher sea level by fluvial processes in current river channels, floodplains, estuaries, deltas and other near-shore environments (see low-lying coastal swamps). These unconsolidated sedimentary aquifers store and transmit groundwater through inter-granular voids between gravel and sand particles.

At high tide marine water from canals infiltrates adjacent unconsolidated sedimentary aquifers. A thin lens of fresh groundwater is supported above the saline marine water which may then discharge back into the canal at low tide. These areas may support fauna and flora communities, ecological processes and delivery of ecosystem services.

• Estuarine canals estates may depend on the surface expression of groundwater from the underlying unconsolidated sedimentary aquifers.
• Unconsolidated sedimentary aquifers associated with estuarine canal estates may also support aquifer ecosystems which can be indicated by the presence of stygofauna.

Pictorial conceptual model PDF