Geofabric Hydrology Reporting Catchments comprises two related views of hydrological catchments to be used for 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 and inland sinks. It also contains a new class of node called diffuse nodes that represent diffused flow from groups of nodes at coastal, delta or inter-catchment outlets.
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 (that are aggregations of AHGFCatchments) 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 based on upstream relationships.
This product contains five feature types including: Node, Link, Contracted Catchment, Node-Link Connectivity (upstream), and Node-Link Connectivity (downstream).
Metadata ConstraintsThe authoritative (Point of truth) full version of this metadata record is under copyright, and available from [ http://www.bom.gov.au/metadata/19115/ANZCW0503900107 ]. Licence details about harvesting and derivative versions of the metadata are included there.
PurposeGeofabric Hydrology Reporting Catchments is designed to meet two specific use cases. Firstly, the contracted catchments are designed to build stable reporting regions and secondly, the simplified node-link network is designed to be used as input to hydrological modelling environments, to identify nodes, reporting reaches and their associated catchments.
The AHGFContractedCatchment feature class is designed to represent geographic surface boundaries that have a hydrological relationship to surface water features. These catchment boundaries in their current form may not completely satisfy legislative or business requirements, but are intended to provide the building blocks for reporting regions such as those given in Geofabric Hydrology Reporting Regions. The AHGFNode and AHGFLink feature classes provide a simplified, dendritic node link network for input into hydrological models.
CreditGeoscience Australia, Canberra; CSIRO, Water for a Healthy Country; ANU, Fenner School of Environment and Society
Geofabric Hydrology Reporting Catchments is part of a suite of Geofabric products produced by the Australian Bureau of Meteorology. The geometry of this product is derived from the Geofabric Surface Network product. It consists of AHGF Node, AHGF Link and AHGF Contracted Catchments as well as AHGF Node-Link Connectivity tables for both upstream and downstream network tracing. The outflow point for each AHGF Contracted Catchment is based on a Contracted Node and the boundaries of the underlying AHGF Catchments. The feature class terminology for Geofabric Hydrology Reporting Catchments components has been modified to distinguish it in terms of the products underlying data model.
The AHGFContractedCatchments are aggregations of the 9 second catchments that participate in a relationship of common areal extent, based upon the location of a Contracted Node from both the Geofabric Surface Cartography and Geofabric Surface Network products. The types of contracted nodes and the levels of contracted confidence are further described in the Geofabric Product Guide.
1. re-composited feature classes in the Geofabric Maintenance Geodatabase Feature Dataset are assigned unique Hydro-IDs using ESRI ArcHydro for Surface Water (ArcHydro: 126.96.36.199 and ApFramework: 188.8.131.52)
2. feature classes from the Geofabric Maintenance Geodatabase Feature Dataset are extracted and reassigned to the Geofabric Hydrology Reporting Catchments Feature Dataset within the Geofabric Hydrology Reporting Catchments Geodatabase.
A complete set of data mappings, from input source data to Geofabric Products, is included in the Geofabric Product Guide, Appendices.
Changes at v2.1
! Further simplification of the Node-Link network to give a dendritic
Changes at v2.1.1
! Improvements to the quality of simplified Node-Link network (AHGFNode and
AHGFLink) and Catchment Hierarchy (AHGFContractedCatchment) via the addition
of diffused Inter-catchment nodes and merging of dangling sink nodes:
+ East: Murray-Darling completely reprocessed with addition of 116 new
diffused Inter-catchment nodes and 62 dangling sink nodes merged.
+ South-Central: Addition of 11 new diffused Inter-catchment and 36
dangling sink nodes merged (fixes problems with disjoint contracted
+ North: Addition of 3 new diffused Inter-catchment, 1 dangling sink
nodes merged and 2 disjoint contracted catchments fixed.
+ West: Addition of 5 new diffused Inter-catchment nodes, 5 dangling
sink nodes merged and 1 disjoint contracted catchment fixed.
! Layer file revised to include sub-catchment view of
! Supplemental table, PrefFlowNodesV2-1-1.dbf, included providing list
of identifiers for ‘preferred flow’ nodes used in v2.1.1 (see
HR_Catchments_Technical_Overview.pdf for more info).
- 2 connectivity tables AHGFNodeLinkConnectivityDown and
AHGFNodeLinkConnectivityUp corrected by adding missing 'AHGF' prefix to