How to check flood risk on a NSW property

To check flood risk on a NSW property, start with the section 10.7 planning certificate attached to the contract: it must say whether the land is in the flood planning area and subject to flood-related development controls. Then check the council's flood maps and studies, get an insurance quote before you exchange, and look for signs of past water on site.

Flooding isn't only a river problem. Overland flow from heavy rain, low points in a street and blocked stormwater can flood homes far from any creek.

Step 1: Read the planning certificate

Every NSW contract for sale must include a section 10.7 planning certificate from the council. It answers two flood questions:

• Is the land within the flood planning area and subject to flood-related development controls?
• Is the land between the flood planning area and the probable maximum flood and subject to flood-related development controls?

The answers can be yes, no or unknown.

• Yes to the first question means the land is in the area where council applies flood controls. That can affect what you can build, how high floors must be, and insurance.
• Yes to the second question means the land is outside the main flood planning area but could still be affected in a very rare, extreme flood.
• Unknown means the council doesn't yet have the mapping to say. Treat it as a reason to check further, not as a clear answer.

The certificate may also include other flood information the council holds. Read the whole certificate, not just the yes or no.

Step 2: Check the council's flood information

Most councils publish flood studies and floodplain risk management plans, and many have online flood maps. Look for:

• The flood planning area and flood planning level for the street
• Overland flow paths, which often follow roads and natural low points
• Any flood study under way that could change the mapping

You can also find statewide flood information through the NSW Government's flooding pages at planning.nsw.gov.au/flooding and the NSW Flood Data Portal.

Council flood maps don't cover every street equally, which is why the planning certificate matters: it's the council's answer for that specific lot.

Step 3: Get an insurance quote before you exchange

Ask an insurer for a home insurance quote, including flood cover, before you exchange. A very high premium, a large flood excess, or flood cover being unavailable are all strong signals. Lenders usually require insurance from settlement, so you want to know the cost early.

For apartments, check the building insurance in the strata report and any history of water damage claims.

Step 4: Look for signs on site

• Water stains, tide marks or new paint low on walls, in the garage or under the house
• Damp, musty smells, mould or lifting floors
• Sandbags, flood barriers or raised power points and appliances
• A property lower than the street, or at the bottom of a slope
• Drains, gutters and stormwater pits that look blocked or overloaded

Your building and pest inspector can report on damp and drainage, but they won't tell you the flood mapping. See what a building and pest report doesn't tell you.

Step 5: Ask the right people

• The selling agent: has the property ever flooded or had water come inside? Any insurance claims?
• The council: what does the flood mapping show, and is a new flood study coming?
• Neighbours: locals often remember the last big storm.
• Your solicitor or conveyancer: what does the certificate mean for this contract?

Flood terms in plain English

• 1% AEP flood: a flood with a 1% chance of happening in any year (sometimes called a "1 in 100 year" flood). It can happen two years in a row.
• Flood planning level: the height councils use for setting floor levels and other controls, usually the 1% AEP flood plus a safety margin called freeboard.
• Probable maximum flood (PMF): the largest flood that could reasonably happen. Rare, but important for safety planning.
• Overland flow: stormwater flowing over the ground during heavy rain, rather than a river or creek breaking its banks.

Questions

Does every NSW property have a flood answer on its planning certificate?

Yes. The section 10.7 planning certificate must answer the flood questions for the lot, though the answer may be "unknown" where the council's mapping isn't complete.

If the certificate says no, is the property safe from flooding?

It means the land isn't in the mapped flood planning area. It doesn't rule out overland flow, stormwater problems or a very rare flood, so still check the site and get an insurance quote.

Can I get flood insurance on a flood-affected property?

Often yes, but it can be expensive or come with a large excess. Get a quote before you exchange.

Will flood controls stop me renovating?

Not usually, but they can set minimum floor heights or other conditions for new building work. Ask the council or a town planner if you're planning big changes.

Where do I find the planning certificate?

It's attached to the contract for sale. If you don't have the contract yet, ask the selling agent for it before you make an offer.

Keep reading

• Bush fire prone land in NSW: what buyers should know
• First home buyer checklist for NSW
• Building and pest inspection cost in Sydney
• How much does a strata report cost in NSW?

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