Dataset Title: Hydrographic Catchments - Basins

Custodian: Department of Environment

Jurisdiction: Western Australia

Abstract
The drainage divisions of Western Australia, derived from catchment boundaries defined at
various scales. This dataset is derived from a subset of lines from the Hydrographic Catchments
- Subcatchments data.

Currency and Status

Beginning Date: 01-01-1993
Ending Date: Not Known
Metadata Date: 03-04-2003
Progress: Complete within current limitations on funding, further updates will be done as necessary.
Maintenance & Update Frequency: Ongoing, as required.

Lineage :
1. The gauging station catchment boundaries (including Basin & Division boundaries) were drawn on hardcopy maps in 1994-95,
generally the best available scale topographic maps (1:25 000, 1:50 000, 1: 100 000 and 1:250 000), with reference to the elevation contours.
These maps were digitised and the information stored as a microstation design file. Calculated catchment areas only included sub-areas.

2. The microstation DGN files were converted to ArcView shapefiles and stored as a polygon SDE layer in 2000.
This layer remained unchanged until March 2003.

3. From 1997 to 2002, updates to original catchment microstation (line) file were undertaken off-line and not published.
These updates used the best available DOLA contours and in some cases LandMonitor contours and aerial photography, digital streamlines, and ground truthing.
Boundaries were extended to sites other than gauging stations. Where known, the accuracy is attributed to linework.

4. Updates were incorporated into a single dataset, attributed and published in April 2003.

5. Divisions, Basin and Catchments data are derived from different subsets of the subcatchments data.
Pilbara, Gascoyne and Murchison are fair, while the MidWest, SouthWest and South Coast are good.

Positional Accuracy
Varies depending on the scale of the original contour data used to delineate the basins. Varies between 2m contours and 50m contours.

Attribute Accuracy
Good. Area_km2 and Perim_km calculated in ArcView based on Albers Equal Area (Conic) Projection for WA.

Logical Consistency
Good.

Completeness
As larger scale data become available, and demands dictate, these areas will be redigitised.

Access:
Standard WRC license agreement

Contact Persons

For external data provision:

Brett Harrison
GIS Data Administrator
Information Services
Business Development Division
9278 0719

For scientific content queries:

Peter Muirden
Senior Engineer/Hydrologist (Surface Water)
Hydrology and Water Resources
Resource Science Division
9278 0456

For GIS technical queries:

Dan Sandison
Divisional GIS Coordinator
Regional Services
Regional Operations Division
9278 0554

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DATA DICTIONARY

Basin_name

Basin_no

Division - Name of Hydrographic Division in which basin occurs.

Edited - date on which part of the boundary was last edited (derived from subcatchments linework)

Area_km2 - Area in square kilometres

Perim_km - Perimeter in kilometres