Flood Mitigation in the Coffs Harbour LGA

A community unlike any other

Explore inspiring articles, discover events, connect with locals and learn more about Coffs Harbour City Council.

Build the Best Bypass

Build the Best Bypass

Council, on behalf of the community thanks our State and Federal Governments for supporting our request to use tunnels...

Read more
Cultural Civic Space

Cultural Civic Space

Find out the latest project updates and news...

Read more
Projects

Major Projects

Find out information about major projects we have underway and ones we have recently completed...

Read more
View all news

Latest News

STILL

Local Artists Shine in the City Heart

Artworks by 35 local artists from Byron Bay to Port Macquarie that entered this year’s nationally significant Still: National Still Life Award will go on display in a special exhibition...

Read more
Lifeguard Strategy

Future Lifeguard Strategy Out for Public Comment

Changes in our local population and the reasons people visit beaches, plus innovations in lifesaving technology are captured in a Draft Lifeguard Service Strategic Plan...

Read more
Solar

Switching on to Solar

Work has begun on the first sites chosen for Council’s major solar energy push to help reach its target of using 100% renewable energy as an organisation by 2030...

Read more
View all news

Flood Mitigation in the Coffs Harbour LGA

​​​The Great Dividing Range passes very close to the coast in the Coffs Harbour local government area. With the proximity of the coastal ranges to the ocean, the coastal plain has no major river systems, but there are numerous small creek systems. Overall there are 16 major coastal creeks plus the inland waterways of the Bobo River, Little Nymboida River, Bucca Creek and Orara River. 

Map of waterways & catchments in Coffs Harbour (1MB)

Climate & Rainfall

Coffs Harbour experiences a moderate climate, which has been classified as humid sub-tropical. This is characterised by warm to hot summers and mild winters. The area experiences a high rainfall, averaging 1700mm annually, with most rain falling in late summer and early autumn. The cooler months receive much less rainfall, and dry spells are not uncommon from April to October.
 
Landform has a strong influence on rainfall within the area. Higher rainfall occurs east of the coastal range, due to moist maritime air rising over the land, and can lead to high intensity storms.

Because the catchments are steep, relatively small in area and subject to high rainfall intensities, they experience what is termed 'flash flooding'.

​Flash flooding is:

  • flooding that peaks within six hours of the rain that caused it;
  • very sudden, with little warning of its coming;
  • a result of local heavy rainfall;
  • characterised by rapid rises of stream levels with elevated levels experienced for short periods of time.

Flood Mitigation Programme

Council made its Coffs Creek Catchment Flood Mitigation Programme a priority after the 2009 floods. It includes four flood detention basins.

Funds for the Programme were secured through a $6m loan and a special rate variation that raised $6m in total.

Bakers Road Detention Basin

The largest of the detention basins was completed at William Sharpe Drive, West Coffs, in 2010. 

Bennetts Road Detention Basin

The Bennetts Road basin construction was finished in December 2012.

Spagnolos Road Detention Basin

The basin was officially opened in March 2015.

Upper Shephards Lane Basin

Work was completed in December 2018.

Flood Warning System​

Rain gauges and water level recorders have been installed at key locations and are operational. The recording and radio communication systems are fully operational and linked to the Bureau of Meteorology and State Emergency Services which have provided very positive feedback regarding the assistance this provides emergency services.

History of Flooding in Coffs Harbour

There is a long history of flooding in the Coffs Harbour LGA. Significant flood events have occurred in 1917, 1938, 1950, 1963, 1974, 1977, 1989, 1991 and 2009.

In November 1996, a natural disaster was declared when Coffs Harbour experienced major flash flooding with some 800 properties flood affected. The 1996 storm event caused inundation above floor level of over 250 residential properties and 210 commercial or public properties. 300 people were evacuated.

In 2009, a storm on 31 March saw Coffs Creek peak at 5.14m resulting in flash flooding in the Coffs Harbour CBD and surrounding streets.

On 5 November 2009, another major storm saw more than 500mm of rain fall within 48 hours,​ resulting in further flash flooding in the city centre area.