Australian Hydrological Geospatial Fabric (AHGF) (Geofabric) V3x

The AHGF: Australian Hydrological Geospatial Fabric (Geofabric) is a specialised Geographic Information System (GIS). It identifies the spatial relationships of important hydrological features such as rivers, catchments, waterbodies, aquifers canals and monitoring points.

By detailing the spatial dimensions of these hydrology features and how they are connected, it is possible to analyse how water flows, is stored, transported and used through the landscape.

The enduring nature of the Geofabric is based on a set of contracted nodes (points) which represent important hydrological features in the landscape. A subset of the contracted nodes is used to create a simplified node-link network with associated contracted catchments. There is also a hierarchy of catchments, as well as alternate representations to meet varied user requirements and a toolset that supports customisation.

The Geofabric includes 6 products; Surface Hydrology Network Surface Hydrology Cartography Surface Hydrology Catchments Hydrology Reporting Catchments Hydrology Reporting Regions Groundwater Cartography

Surface Hydrology Network product:

Network representation of hydrological features, including over 2.5 million stream segments and 6000 gauging stations, with the ability to trace the drainage the network both upstream and downstream and identify contributing catchment areas. Can also be used with the Geofabric Toolset to create customised catchments and networks.

The Surface Hydrology Network product provides a set of related feature classes to be used as the basis for production of consistent hydrological surface stream network analysis. This product contains a topographically consistent representation of the (major) surface water features of Australia (excluding external territories). Contains six datasets: Waterbody, Network Stream, Network Node, Catchment, Network Connectivity (Upstream) and Network Connectivity (Downstream).

Surface Hydrology Cartography product:

Cartographic representation of surface hydrological features, based on best available mapped features, approximating 1:100,000 scale, for contextual purposes and production of consistent hydrological cartographic maps.

The Surface Hydrology Cartography product contains a geometric representation of the (major) surface water features of Australia (excluding external territories). Primarily, these are natural surface hydrology features but the product also contains some man-made features (notably reservoirs, canals and other hydrographic features. Contains thirteen datasets: Waterbody, Mapped Stream, Mapped Node, Dam, Structure, Canal Line, Monitoring Point, Water Pipeline, Hydro Point, Hydro Line, Hydro Area, Mapped Connectivity (Upstream) and Mapped Connectivity (Downstream).

Surface Hydrology Catchment product:

National catchment boundaries (NCB) derived from the 1 second Digital Elevation Model using ANUDEM, with approximately 7 million base level catchments, designed to represent geographic catchment boundaries that have a hydrological relationship to surface water features.

The Surface Hydrology Catchments product provides a hierarchy of catchments, with base AHGFCatchment defining a catchment for every stream segment contained within the Geofabric Surface Network along coastal draining and sink basins. ANUDEM processing provided an additional 2 AHGFCatchment aggregated features, these being NCB Level 2 Drainage Basin Group and NCB Level 1 Drainage Division. These 2 aggregate layers are somewhat superseded by Geofabric Hydrology Reporting Regions; River Region and AWRA Drainage Division. Contains three datasets: Catchments, NCB level 1 Drainage Division and NCB Level 2 Drainage Basin Group.

Hydrology Reporting Catchment product:

Geofabric Hydrology Reporting Catchments comprises two related views of hydrological catchments to be used for modelling, analysis and reporting purposes. Firstly, a topological network view of hydrological catchments represented as a simplified node-link network using a subset of the contracted nodes (AHGFNode) and the links (AHGFLink) between them; and secondly, a catchments view of the hydrology using the contracted catchments (AHGFContractedCatchment).

The AHGFNode feature class contains contracted nodes that are points of hydrological significance that carry identity. They include the confluence of major named streams, coastal stream termini, waterbody inflow and outflows, important gauging stations and inland sinks. The AHGFLink feature class provides the topological connectors between a subset of contracted nodes that participate in the simplified node-link network. The AHGFContractedCatchment feature class contains catchment polygons for the subset of contracted nodes that participate in the simplified node link network. These catchments are part of a hierarchy that can be aggregated and traced based on upstream relationships. Contains five datasets: Node, Link, Contracted Catchment, Node-Link Connectivity (upstream), and Node-Link Connectivity (downstream).

Geofabric Hydrology Reporting Regions product:

Reporting regions based on aggregations of contracted catchments, similar to 1997 Australian Water Resource Council (AWRC) Drainage Division and River Basin boundaries, as well as important Gauging Station contributing catchments, for provision of a stable set of reporting boundaries at both the national and regional scale.

It contains three levels of hydrological reporting regions. The first delineates national level drainage divisions, the second delineates regional level river regions across Australia and the third important Gauging Station catchments that represent upstream contributing catchments, which are also used in hydrological modelling. Contains five datasets: AWRA Drainage Division, AWRA Drainage Division Contracted Catchment Lookup, River Region, River Regions Contracted Catchment and Station Catchments.

Groundwater Cartography product:

Groundwater Cartography is a national collation of existing groundwater mapping including aquifer boundaries and properties (structure contours, salinity, outcrop and yield). It has been developed to collate and integrate state and regional groundwater mapping datasets across Australia. It provides foundation groundwater datasets essential for groundwater assessments, management, planning, modelling and research.

The data set is intended to be used at the regional to national scale and does not support local scale groundwater applications. Contains five datasets: Aquifer Boundary, Aquifer Outcrop, Aquifer Contour, Aquifer Salinity and Aquifer Yield.