In response to water management and usage issues, certain areas within the state have been prescribed in order to equitably share and manage the water resources and control future water extraction processes. The prescription may be placed on surface water areas (e.g. farm dams), groundwater (areas of bores and wells) or watercourses (streams and rivers) or a combination of types. This layer contains the linework delineating the watercourses which have been prescribed through legislation (Water Resources Act 1997). It is maintained as the master linework of the prescribed watercourses within the state. This layer will mainly be used for administration purposes for water licensing. This dataset only provides details of prescribed watercourses (streams and rivers) while the associated datasets, Prescribed Surface Water Areas and Prescribed Wells Areas, contains the linework for the prescribed surface water areas and ground water areas within the state. The Water Resources Act 1997 defines the principles for prescribing a watercourse and the resource management policies. Each prescribed watercourse requires a Water Allocation Plan to be prepared by the appropriate Catchment Water Management Board.

In response to water usage issues, certain areas within the state may be prescribed in order to control future water extraction processes. The prescription may be either area based or watercourse based (or in some area both eg Barossa). This layer contains the linework of the groundwater areas which have been prescribed through legislation. This layer is maintained as the master linework of the prescribed areas within the state.

This layer contains the linework of the water resource areas (surface water, groundwater and watercourse) which have been prescribed through legislation. This layer is maintained as the master linework of the prescribed areas within the state. Please refer to the metadata document for more information.

The catchment layer contains boundaries of watersheds where surfacewater drains to a common point into the sea or a major waterbody. Attributes include drainage division, basin (name and number), catchment name and drainage type. Related layers include sub-catchments, reservoir catchments and gauging station catchments.

Surface Water Management Areas for Western Australia were derived in consultation with the regional offices, geometry is based on hydrographic subcatchments. Regional Department of Environment officers identified areas of similar management requirements to define boundaries. Management areas will be used for licencing and administrative purposes. Purpose: The Surface Water Management Area data was developed in order to give a clear understanding of surface water availability and to provide management tools to make good water allocation and natural resources management decisions. Dataset was formally known as Surface Water Management Areas (DOW-020)

The DWER Water Information Sites dataset lists monitoring locations (sites) where surface water and groundwater data are collected to assess the quality and quantity of state water resources. This monitoring supports a comprehensive understanding of the state's water assets and underpins evidence-based decision-making for both regulatory and resource management purposes. Please note that the dataset presents only summary-level attribute information for each site. It does not include all available data, which may encompass individual measurements such as water depth, stream height, water quality, rainfall, and bore details including construction, lithology, and stratigraphy. For access to detailed data, please visit the Water Information Reporting (WIR) system. (https://wir.water.wa.gov.au/).

The sub-catchment layer contains boundaries of discrete areas within catchments that each defines the watershed of a major tributary or tributaries. Attributes include the names of basin, catchment and sub-catchment, and sub-catchment area. Related layers include catchments, reservoir catchments and gauging station catchments.

Statewide River Water Quality Assessment (SRWQA) 2004 & 2008 uses water quality data collected as far back as 1998 to determine the status and trends of nine water quality parameters for all waterways in the state, where consistent data is available. The project was undertaken by the Water Science Branch of the Department of Water and Environmental Regulation in 1999 and 2004 has now been updated to include water quality information up to the end of 2007. This dataset only shows the classifications and trends from the 2004 and 2008 assessment. The Assessment focused on colour, dissolved organic carbon, dissolved oxygen, pH, total nitrogen, total phosphorus, total dissolved salts, total suspended solids and turbidity. A total of 255 sites from 23 basins in Western Australia (out of a total of 44) were included in the 2008 update with 126 of these being assessed for the first time in 2008. In 2004 232 sites were assessed. Due to a lack of data numerous sites that were assessed in 2004 are not included in the 2008 update. Many basins had no data, whilst the others lacked recent monitoring data. The status and trend results were compiled into an excel spreadsheet. Dataset was formerly known as Statewide River Water Quality Assessment (DOW-056)