Bass Coast Shire Council

Flood information for the Bass Coast Shire Council, encompassing local flood guides and a Municipal Flood Emergency Plan.

On this page:

 

Bass Coast Municipality Map
Bass Coast Municipality Map.

Bass Coast Shire Council has a history of flooding including significant flood events in July 2007 and May 2012 which impacted the townships of Wonthaggi, Kilcunda and Dalyston and cut several major roads.

Flooding usually occurs as a result of prolonged moderate to heavy rain across Shire.

This includes successive cold fronts, often during winter and spring, that brings periods of rain that wets the catchments and primes them for flooding from further fronts. 
 

 

 

 

Are You at Risk of Flood?

Bass Coast Areas of Flood Risk
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There  is  little  recognised  riverine  flooding  risk  in  Bass  Coast  with  the  majority  of  impact being  too  low  lying  rural  land  and  roads. Riverine  flooding  can  cause  isolation  when access/egress roads are cut by flood  waters. 

Prolonged  moderate  to  heavy  rain  often  leads  to  flooding  within  the  Shire  and  generally  occur as a result of moist warm airflow from Northern Australia bringing moderate to heavy rainfall over a period of 12 hours or more following a prolonged period of general rainfall. The period of  general  rainfall  “wets  up”  the  catchments  and  (partially)  fills  both  the  on‐stream  dams  and  the  natural  floodplain  storage. These  combine  to  increase  the  runoff generated during the subsequent period of heavy rainfall. 

Successive cold  fronts, often during winter and spring,  during winter and  spring, that bring periods of rain that wet up the catchments and prime them for flooding from a further front or complex low pressure system that is perhaps slower moving and / or brings heavier rainfall. 

A low pressure system (often intense and known as an ‘east coast low’) that develops within eastern Bass Strait or over the Tasman Sea and directs moist air  for a period of  12  hours  or  more onto West Gippsland. The lifting that occus as it travels inland reults in heavy rain and possible flooding.

The earlier stages of an east coast low, as a low pressure system moves from the west and 
deepens over Bass Strait, tends to result in the heaviest rainfall over the catchments of the streams that flow through Bass Coast.

Short duration, high intensity rainfall (usually associated with thunderstorms) can also cause  localised  flooding along  overland  flow  paths and within  urban areas if  the  capacity  of  the  stormwater  drainage  system  is exceeded. Such events,  which  are mainly  confined  to  the  summer months, do not generally create widespread flooding since they only last for a short  time  and  affect  limited  areas. 

Flooding  from  these  storms  occurs  with  little  warning  and  localised damage can be severe. High intensity rainfall associated with thunderstorms (ie average rainfall rates of more than  35mm/hour  for  30  minutes  or  more  or  17mm  in  30  minutes)  is  likely  to  lead  to  flash  flooding, across the urbanised parts of the Shire.

Blocked  or  capacity  impaired  stormwater  drains  can  also  lead  to  overland  flows  and associated flooding: the drain surcharges and excess water flows above ground. 

High tides on top of storm surge associated with an extra low pressure system and on‐shore  winds,  can  exacerbate  flooding  within  the  coastal  areas  of  the  Shire  or  create  areas  of  flooding  in  and  around  the  drainage  network. 

Due  to  the  proximity  of  Bass  Strait  to  the  coast  and  Western  Port,  rises  in  coastal  ocean  levels  may  reduce  the  capacity  of  the  waterways  and  storm‐water  drains  to  discharge  runoff,  while  extreme  storm  events  can  cause  backflow  to  the  point  where  water  surcharges  back  above  ground  around  the  drainage pits and channels.

About Flood Guides

Communities can use local flood guides to identify and better understand their local flood risk. They include information about: flood history, how to prepare & respond to floods and who to contact.

Contact Information

For more information, contact the Gippsland (East) Regional Headquarters.
For information on flood warnings, see the VicEmergency website
Visit the Bass Coast Shire Council website.
Your local Catchment Mangement Authority: West Gippsland.

Local VICSES Units

Inverloch VICSES Unit:
Bear St, Inverloch

Phillip Island VICSES Unit: 
125/127 Settlement Road,
Cowes, Victoria  3922

San Remo VICSES Unit: 
Davis Point Road,
San Remo, Victoria  3925

Wonthaggi VICSES Unit: 
319 White Road,
Wonthaggi, Victoria,  3996

Municipal Flood Emergency Plan (MFEP)

Municipalities can use Municipal Flood Emergency Plans to prepare, respond and recover from flood and storm events. Bass Coast Municipal Flood & Storm Emergency Plan - Updated Dec, 2018