Skip links and keyboard navigation

Alluvia—closed drainage systems

Evaporation Eucalyptus spp. Eucalyptus spp. Evaporation Infiltration and percolation Direction of groundwater movement Direction of groundwater movement Direction of groundwater movement GDE GDE GDE GDE GDE GDE GDE GDE GDE GDE GDE Evapotranspiration Evapotranspiration Evapotranspiration Evapotranspiration Evapotranspiration Evapotranspiration Evapotranspiration Evapotranspiration Eucalyptus spp. Eucalyptus spp. Eucalyptus spp. Eucalyptus spp. Eucalyptus spp. Eucalyptus spp. Negligible groundwater movement Negligible groundwater movement Stygofauna Mixing of groundwater and surface water Alluvia (unsaturated) Low permeability rock or clay fish Low permeability rock or clay Alluvia (saturated) Focal point Negligible groundwater movement Low permeability rock or clay Eucalyptus spp. Evapotranspiration Fish Stygofauna Alluvia (saturated) GDE

Click on elements of the model or select from the tabs below

Click on elements of the model or select from the tabs below

Alluvial aquifers are formed from particles such as gravel, sand, silt and/or clay deposited by fluvial processes in river channels or on floodplains. These deposits store and transmit water to varying degrees through inter-granular voids. Alluvial aquifers can develop in areas where groundwater flow is constrained by the surrounding lower permeability material. In closed drainage systems alluvial aquifers are completely constrained by local geology and topography, combined with high evaporation. Therefore, groundwater and surface water is unable to continue flowing and are stored in these areas.

Unconsolidated sedimentary aquifers in upper catchment areas may provide a range of ecosystems with water required to support their fauna and flora communities, ecological processes and delivery of ecosystem services.

  • Palustrine (e.g. swamps) and lacustrine (e.g. lakes) wetlands and riverine waterbodies may depend on the surface expression of groundwater from these unconsolidated sedimentary aquifers which are supported by surrounding permeable rocks.
  • Terrestrial vegetation fringing channels on alluvia may depend on the subsurface presence of groundwater in these unconfined, sedimentary aquifers.
  • Unconsolidated sedimentary aquifers in alluvial deposits may also support aquifer ecosystems which can be indicated by the presence of stygofauna.

Pictorial conceptual model PDF


Last updated: 12 April 2017

This page should be cited as:

Alluvia—closed drainage systems, WetlandInfo 2015, Queensland Government, Queensland, viewed 14 December 2018, <https://wetlandinfo.des.qld.gov.au/wetlands/ecology/aquatic-ecosystems-natural/groundwater-dependent/alluvia-closed-drainage-systems/>.

Queensland Government
WetlandInfo   —   Department of Environment and Science