We acknowledge the Bundjalung, Gumbaynggirr and Yaegl as the Traditional Custodians of the Clarence Valley area.
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Clarence Valley waterways
The Clarence River is NSW’s largest coastal river system, including water volume and catchment area. It has a long history of regular flooding. Major floods have been recorded since 1890, including 1954, 1974, 1996, 2001, 2009, 2011, 2013, and 2022.
The Clarence River’s major tributaries include the Mann River, Nymboida River and Orara River, with the river mouth estuary reaching over 100km inland to Copmanhurst.
Grafton and Maclean are two of the larger townships on the Clarence River and both have levee systems built to protect them from major flooding.
Find out more about how levees work at Levees
What causes flooding in Clarence Valley?
Watch this video to find out more about how floods move through the Clarence River catchment and its communities.
Climate change is expected to bring heavier rainfall and higher sea levels, which will make flooding worse in the Clarence Valley region.
Every flood is different. While NSW SES can provide guidance on what may occur in future floods, it's important to remember that predictions are not guarantees.
Clarence Valley communities
To find Community Resilience Networks in Clarence Valley region and learn more about how these communities are responding to floods, email Clarence Valley Council at council@clarence.nsw.gov.au.
Grafton and South Grafton
Grafton and South Grafton are protected by levee systems. The Grafton levee (7.95m) shields most of the city, while the South Grafton levee protects areas near Big River Way.
Floods outside the levee can still cut off rural properties, close roads, and damage farms.
In moderate floods, rural land outside the levees, such as Carrs Island and Southgate, are inundated and properties isolated.
In South Grafton, if the Waterview levee fails, the water flows south. Rising water can also cut off bridges and evacuation routes. If the levee is fully overtopped, around 12,000 people and 5,742 homes could be affected.
Maclean
Maclean is built on the floodplain of the Lower Clarence River, which means it’s at risk of flooding. Floods in Maclean can happen because of heavy rain in the upper catchment, combined with high tides, storm surges from the ocean, and local rain. These factors together can cause major floods that last a long time and ease slowly.
Major floods have happened in the past, including in 1890, 1921, 1950, 1954, 1974, 1996, 2001, 2013, and 2022. Before the levee was built in 1976, floods often hit the town centre and homes, cutting off the community and causing serious damage.
Maclean is protected by a levee that’s about 3.3m high on the local flood gauge. It works alongside floodgates and pump stations to help manage floodwater. However, if the river stays high for a long time or there’s heavy local rain, the system can struggle to keep up.
In major floods, the levee helps stop floodwater from reaching the town centre, homes, and important services. But if the levee is ever overtopped, floodwater would quickly flow into the town like water filling a basin.
Properties, key evacuation routes, roads and services would be at risk. This could damage homes, roads and utilities like electricity, gas and water. The community may be isolated for a very long time. Flooding outside the levee affects rural properties, riverbank infrastructure, and low-lying roads. In moderate/major floods, areas outside the levee become isolated, with road closures making it hard to get in or out.
Climate change is expected to bring heavier rainfall and higher sea levels, which will make flooding worse in Maclean and nearby areas.
Every flood is different. While NSW SES can provide guidance on what may occur in future floods, it's important to remember that predictions are not guarantees.
Lawrence
Lawrence is located on the north bank of the Clarence Valley at the junction with Sportmans Creek, approximately halfway between Brushgrove and Maclean. Most of the town does not flood, however there are residential and non-residential properties that may experience flooding, and some residents may need to evacuate.
The periods of isolation for these areas can vary depending on the size and duration of the flood. Any residents wanting to leave the area would need to do so before the onset of flooding causes local road closures.
Coutts Crossing and Nymboida
The Orara and Nymboida Rivers flow through narrow valleys and are prone to regular flooding. Towns like Coutts Crossing and Nymboida, located near these rivers, are above major flood levels. However, surrounding areas can become isolated when local roads close due to floodwaters. Affected areas include Middle Creek, Lower Kangaroo Creek, and others near Coutts Crossing, as well as Buccarumbi and Billy's Creek near Nymboida.
The duration of isolation varies with the severity of the flood, so residents must evacuate before roads become cut off.