How to Use the Map Links

The links will take you to Council’s public mapping system.

• You will need to read and accept the terms and conditions to proceed.

• The 'General' module is the default and the mapping may open in that module.
• To access the draft flood mapping, click on the module called 'Flood Consultation 2024'.

• The 'Flood Consultation 2024' module has a number of layers in a group called 'Draft Wollondilly Flood Study 2024':

• Groups of layers are expanded with a click on '+' (plus) and compacted again with a click on the '-' (minus)

• Under the main group, there are also sub groups of maps for different flood information:

• Flood Planning Areas are where planning controls will normally affect a proposal.
• Flood extent mapping is available for the 10% AEP, the 1% AEP, the 1 in 500 AEP and the PMF events.
• Flood depth mapping shows the depth of flooding for the same events.

• The layers (and groups) are displayed with a tick in the box on the left 

• There are many layers available to view. The top one (that comes first in the layer list) will show over the top of other lower ones.

• The full list of maps available (with no flood mapping turned on):
  

• A handy button to use is the Legend Tool in the top right corner:

• If you click that button, the Legend will then pop up on screen:
  
• It can be useful if some of the layers are hidden behind others.
• The Legend can be moved around (click and drag on the top bar) or closed again by clicking the 'X'

• Finding a property is easy. You can either zoom in and click on a property, or use the search tools: either across the bottom of the screen or via a magnifying glass icon at the bottom.

• Type in the address until the correct property is listed, and select that - then click “search”. 

• If a property details screen appears, you can minimise it with the down arrow at the top of screen.
• On the map, the property selected will have a red border and sit in the middle of the map. 
• You can zoom in and out with the “+" and "-" tools or by scrolling the mouse.

• There are several layers that show the varying depths (from 5 cm to greater than 4 metres) of each of the modelled flood events:

• 10% AEP Flood Extent (1 in 10 chance flood)
• 1% AEP Flood Extent (1 in 100 chance flood)
• 1 in 500 year flood
• Probable Maximum Flood Extent

• Choose which layer you would like to view.  
• E.g. Flood mapping for the Flood Depth in the 10% AEP flood event (with the depth ranges expanded):

•  Flood Planning Area Mapping (Based on the 1% AEP Flood map):

• The maps look at the worst case for a given flood probability, and extend that across a wide area.
• That means that the worst case flooding in one place may be from a different storm than the worst case flooding somewhere else.
• That also means that the extent of the flooding shown for a given probability will never happen during a single event. 
  E.g. a 1% AEP flood extent in your street might be from a two hour storm ...
  But the 1% AEP flood extent for Nepean River results from a storm over 24 hours. 
  The storm that floods the street will result in a much lower flood in the river.