Flood Study Report
If your property is mapped within a council's flood planning area, a flood study or, for a simpler site, a flood advice letter assesses your flood risk and determines requirements like minimum habitable floor levels, flood-compatible materials below that level, and safe access and egress. It directly shapes the building design, not just the paperwork, so getting it early avoids designing a floor level that later has to be raised. We check your property against council flood mapping before assuming either way.
Free consultation
- 1–3 weeks, depending on whether a full study or advice letter applies
- Quoted per site - typically from $1,000 + GST
- Quoted fixed after a free scope check
Why this belongs before floor levels are drawn
A floor level set before flood requirements are confirmed is one of the more disruptive late changes a project can face, because it can affect ceiling heights, stair runs and even whether the proposed built form still complies with height controls. Confirming flood requirements at concept stage avoids that entirely.
Source: Environmental Planning and Assessment Act 1979 (NSW), s 4.15; relevant council flood planning maps and Development Control Plans.
How it works
Flood mapping check
1–2 days
Confirm whether the property sits within a mapped flood planning area and at what category.
Advice letter or full study
1–2 weeks
A flood advice letter is prepared for straightforward sites; a full flood study is commissioned where risk is more complex.
Design integration
3–5 days
Minimum floor levels and construction requirements integrated into the architectural and structural design.
What we take off your hands
What EHUP handles
- Checking your property against council flood mapping before assuming risk either way
- Coordinating a flood advice letter for straightforward sites, or a full flood study where needed
- Confirming minimum habitable floor levels and flood-compatible construction requirements
- Integrating flood requirements into the design before floor levels are locked in
What you don't have to deal with
- A floor level set below what council's flood mapping actually requires
- A full flood study commissioned where a simpler advice letter would have been enough
Frequently asked questions
How do I know if my property is flood-prone?
Council flood mapping is checked against your specific address - it is not something to assume from a general area reputation, since flood planning areas can be quite localised even within the same street.
What is the difference between a flood advice letter and a full flood study?
A flood advice letter is a shorter assessment suitable for straightforward sites with well-established flood data; a full flood study is a more detailed hydraulic assessment used where flood behaviour on the specific site is more complex or less well documented.
Does this affect my design, or just approval paperwork?
It affects the design directly - minimum habitable floor levels, flood-compatible materials below that level, and safe access during a flood event are all building requirements, not just conditions added after the design is finished.
Related services
Stormwater Drainage Plan
Stormwater is assessed as part of every DA's general merit assessment, but the engineering standard comes from your council's own specifications - typically requiring on-site stormwater detention (OSD) so your development does not increase peak flood flows onto downstream properties.
Development Application (DA)
A Development Application is the merit-assessed approval pathway.
Specialist Reports
Most applications of any size need reports from specialists outside town planning.
Why clients choose EHUP
- 10+
- 250+
- 14
- 1
Not sure which approval you need?
Tell us the address and what you want to do. We'll help identify the appropriate planning pathway, whether it is exempt development, complying development or a full DA. Your first conversation is free.