Perth Flood Risk Assessment - Homeowner Bylaw Guide

Environmental Protection Western Australia 3 Minutes Read · published February 11, 2026 Flag of Western Australia

Perth, Western Australia homeowners should assess flood risk before buying, renovating or lodging development applications. This guide explains practical steps to determine site flood exposure, how local planning and building approval pathways interact with flood controls, and where to find official maps and contacts to meet Perth bylaw requirements.

Assessing Flood Risk — First Steps

Start by locating your property on official flood mapping, review any applicable local planning overlay, and check current building requirements for floor levels, drainage and stormwater. Engage a suitably qualified flood consultant where site-specific assessment is required. Use official state flood maps and the City of Perth planning resources to confirm constraints and submission requirements[1][2].

Check official flood maps early to avoid wasted time or expense.

Practical Assessment Checklist

  • Obtain official flood mapping and note modelled flood extents and levels.
  • Confirm whether a development application or building permit is needed from the City of Perth.
  • Engage a qualified flood consultant for site-specific assessment where required by planning or building rules.
  • Record site levels, proposed finished floor levels and proposed drainage measures in the application documents.
  • Budget for any required flood mitigation works or changes to design to comply with standards.

Penalties & Enforcement

Flood-related compliance in Perth is enforced through planning and building approval pathways and by local law officers where works or land use contravene approvals. Specific monetary penalties for failing to obtain required approvals or for unlawful works are not stated on the primary City of Perth planning and building pages cited here; refer to the enforcing department for exact figures[2].

If unsure whether works need approval, contact planning before starting construction.
  • Fines: not specified on the cited page for flood/building offences; see the City of Perth enforcement contacts for current penalty amounts.[2]
  • Escalation: first and repeat/continuing offence ranges are not specified on the cited pages; enforcement may escalate from notices to infringement or prosecution depending on circumstances.
  • Non-monetary sanctions: stop-work orders, remedial directions, requirement to obtain retrospective permits, and court action are standard enforcement tools.
  • Enforcer: City of Perth Planning and Building Services and local law officers handle inspections and complaints; use the official contact and reporting pages to lodge queries or complaints.[2]
  • Appeals/reviews: appeal routes typically run through internal review or the State administrative tribunal or relevant court; time limits for appeals are not specified on the cited pages and should be confirmed with the approving authority.
  • Defences/discretion: approved permits, development conditions, or a demonstrated reasonable excuse may affect enforcement; obtain approvals or variances where available.

Applications & Forms

Common applications include development applications and building permit submissions to the City of Perth. The specific form names, application fees and lodgement methods are published on the City of Perth planning and building pages; if a form or fee is not listed on a cited page, it is not specified there and you must contact the department for details[2].

Action Steps for Homeowners

  • Check flood maps and overlays for your address and note required floor levels.
  • Contact City of Perth Planning or Building Services early to confirm permit requirements.
  • Engage an accredited consultant where modelling or reports are mandated.
  • Include mitigation works in your budget and submit accurate documentation with applications.
  • Report suspected unlawful works or flooding hazards to local law enforcement or council via official complaint pages.

FAQ

How do I find out if my property is in a floodplain?
Use the state flood mapping tools and City of Perth planning overlays to check modelled flood extents; contact council planning for clarification.
Do I need a development application for flood mitigation works?
It depends on the scale and location of works; contact City of Perth Planning or Building Services to confirm whether a DA or building permit is required.
Who inspects compliance and enforces flood-related bylaws?
City of Perth Planning and Building Services and local law officers perform inspections and enforcement; lodge complaints via the council contact page.

How-To

  1. Locate your property on official state flood maps and note flood extents and levels.
  2. Check City of Perth planning overlays and building requirements for your parcel.
  3. Engage a qualified flood consultant if a site-specific flood risk assessment is required.
  4. Prepare and lodge any required development application or building permit with supporting flood and drainage documentation.
  5. Complete any required mitigation works to the approved specification and retain records for insurance and future sale.

Key Takeaways

  • Check official flood maps and council overlays before planning works.
  • Engage specialists where required and confirm permit needs with City of Perth.
  • Use official council complaint and contact channels for inspections or reporting.

Help and Support / Resources

  1. [1] Department of Water and Environmental Regulation - Flood information
  2. [2] City of Perth - Planning and Building

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