Policy
State Planning Policy 2.9 Water was published on 16 December 2025 and became operational on 18 December 2025. It supersedes nine instruments, including Better Urban Water Management (2008), SPP 2.9 Water Resources, the Government Sewerage Policy and the flooding provisions of SPP 3.4. It also renames the water planning documents: a District Water Management Strategy is now a District Water Management Report, a Local Water Management Strategy is a Local Water Management Report, and an Urban Water Management Plan is a Subdivision and Development Water Management Report. The content and the planning stages are substantially unchanged. The names, the references and a good deal of published guidance are not.
The renaming, in full
Four documents, four new names. A Regional Water Management Strategy is now a Regional Water Management Report. A District Water Management Strategy is a District Water Management Report. A Local Water Management Strategy is a Local Water Management Report. An Urban Water Management Plan is a Subdivision and Development Water Management Report.
The stated reason is prosaic: the old naming was confused with other water-related documents produced by different agencies, so "strategy" and "plan" both became "report". The explanatory notes are explicit that the content and requirements are substantially unchanged, and that the policy does not apply retrospectively to developments or plans already approved. So an approved LWMS remains an approved LWMS; a new one is a Local Water Management Report.
Which report attaches to which stage
A Regional Water Management Report sits at framework, region scheme, sub-regional strategy and local planning scheme level, prepared by state or local government and approved by the WAPC with DWER endorsement.
A District Water Management Report supports a region scheme amendment, a district structure plan or a local planning scheme amendment. It is prepared by the proponent and approved by the WAPC with DWER endorsement, in close consultation with the relevant local government. It answers whether the land and water resources can support the proposed development, where the drinking and non-drinking water comes from, and what land is required for water management and protection.
A Local Water Management Report supports a local structure plan, precinct structure plan or master plan — same preparation and approval path. It answers how water will be managed within the development, how much land that needs and where, and who delivers the services.
A Subdivision and Development Water Management Report supports subdivision and development applications and local development plans. It is prepared by the landowner or developer and approved by the WAPC with local government endorsement, or by local government with DWER advice if requested. It carries the detailed design that prevents or reduces impacts on water resources. Notably, it is not always required — the guidelines set out three cases where it is not, including where the site will be connected to services to the water service’s satisfaction, or where an approved report already confirms no further report is needed.
The stormwater criteria underneath it
SPP 2.9 points stormwater management at DWER’s Decision process for stormwater management in Western Australia, the Stormwater Management Manual for Western Australia, and the Australian Rainfall and Runoff guidelines. The operative criteria come from the 2017 decision process document and they are more specific than the shorthand people quote.
For small events, the requirement is to manage — retain and/or detain, and treat if required — stormwater runoff from constructed impervious surfaces generated by the first 15 millimetres of rainfall, at source. At source means within lots and road reserves, not routed into a piped system first. For major events, the requirement is to maintain the 1% AEP pre-development flood regime: flood level, peak flow rates and storage volumes. For minor events, systems are designed for serviceability, amenity and road safety, with the applicable event set by the service provider.
Minimum clearances above the 1% AEP flood level are 0.3 metres for road drainage systems and 0.5 metres for terminal retention and detention areas and for major drainage systems and waterways.
One correction worth making, because it appears in a lot of otherwise good documents: the "one year, one hour" criterion is not the current state standard. Chapter 4 of the Stormwater Management Manual, which carried it, has been superseded by the 2017 decision process. It survives in some local government drainage handbooks as a desirable target rather than a requirement — the City of Swan, for instance, treats runoff at source for the one in six months event as a minimum with a one year, one hour storm desirable. Quoting it as the state criterion is a small error that a WA reviewer will notice.