Liverpool Council Stormwater & OSD Requirements for Builders

Stormwater Approval in Liverpool: Two Sets of Rules

Liverpool City is one of the busiest development fronts in Sydney. Greenfield suburbs such as Austral, Leppington, Edmondson Park, Middleton Grange and Carnes Hill are building out rapidly, established areas like Liverpool, Prestons and Moorebank see constant infill and industrial activity, and the Western Sydney Aerotropolis on the LGA’s western flank is reshaping long-term infrastructure planning. For builders, the first thing to understand is that stormwater rules in Liverpool depend on where your site sits.

Which Planning Controls Apply

For most of the established LGA, the governing document is the Liverpool Development Control Plan 2008 (LDCP 2008), which supports the Liverpool LEP and contains Council’s design guidance for drainage and development. Liverpool also maintains a dedicated On-Site Stormwater Detention policy and design specification that sets the technical standard for OSD design.

Critically, land in Austral, Leppington North and parts of Denham Court falls under the Liverpool Growth Centre Precincts Development Control Plan rather than LDCP 2008. That precinct DCP carries its own water cycle management controls tied to the staged delivery of trunk drainage, regional detention basins and biofiltration systems across the precinct. Land near the new airport is subject to the separate Aerotropolis planning framework. Confirm which instrument applies to your lot before any design work starts.

Typical Requirements for Residential Development

• On-site detention (OSD): development that increases impervious area generally requires OSD designed to Council’s OSD specification, with controlled discharge to the street or Council system. OSD must not be located within overland flow paths. Confirm the current permissible discharge and storage criteria with Council before sizing.
• Stormwater drainage plans: a civil engineer’s design showing the lawful point of discharge, pipes, pits, levels and overland flow management is expected with DAs for dwellings, duplexes and townhouses.
• WSUD and water quality: larger projects and subdivisions must address stormwater quality, typically via bioretention, tanks and MUSIC modelling consistent with Council’s requirements.
• Interim arrangements in growth precincts: in Austral and Leppington, lots often drain to trunk infrastructure that is still being delivered. Council will check that your discharge point exists and has capacity, and interim detention or staged connections may be required.
• Easements: low-side lots that cannot drain by gravity to the street need inter-allotment drainage easements – start negotiating early.

Local Factors in Liverpool

• Georges River and Cabramatta Creek: the eastern LGA drains to the Georges River system, with flood-affected land along its corridors that carries floor level and flood-compatibility requirements.
• South Creek catchment: Austral, Leppington and the Aerotropolis drain west to South Creek – a flat, slow catchment where regional basins and water quality controls are central to precinct planning.
• Flat clay country: much of the growth area is flat Cumberland Plain clay with poor infiltration and shallow grades, making pipe cover, overland flow and driveway levels recurring design constraints on small lots.

How Builders Should Prepare

Establish which DCP applies to your site, obtain a detail survey, and confirm the lawful point of discharge – in growth precincts, verify the receiving infrastructure is actually constructed. Have a civil engineer prepare the OSD and drainage package to Liverpool’s current specification before lodgement, and resolve any easement needs up front. Applications with complete, compliant stormwater documentation move through Liverpool’s assessment queue significantly faster.

Contrive Consultants prepares stormwater and OSD designs accepted by Liverpool City Council, including Austral and Leppington precinct work. See our services or contact us – call +61 497 848 111 or email info@contriveconsultants.com.au to discuss your site.