The Clarence River Catchment
The Clarence catchment is located on the far north coast of NSW in the Northern Rivers Region and has a population of about 65000 residents.
The Clarence River is the largest of all NSW Coastal rivers in both catchment area and river discharge. The 250km long river has a catchment area of approximately 22,700 square kilometres and an average annual discharge of almost 3.9 million mega litres.
The catchment is defined by the following divides: the Macpherson Ranges (North); the Baldblair and Doughboy Ranges and the Dorrigo Plateau (South); and the Great Dividing Range (West).
The mouth of the river is located between the towns of Yamba and Iluka, with the tidal limit (estuary) reaching 108km inland to Copmanhurst. The towns of Grafton, Maclean, Yamba and Iluka are the main centres of population along the estuary.
Nearly half of the catchment is managed by National parks or state forests with over 20% of the areas protected in World Heritage Areas, national Parks, and nature reserves. The key catchment management issues are riverbank erosion, gully erosion, invasive weeds, fire management practices, acid sulphate soils, urban and recreational pressures and coastline erosion associated with storm surges.
The 830 square kilometres Clarence floodplain consists of low lying, flat alluvial plains, intersected by lagoons, channels and creeks. The floodplain supports the largest commercial fishing region in the state as well as significant sugar cane, timber and beef cattle industries. Half of the catchment area is utilised for agriculture including a cane industry with an annual gross output of over 12 million dollars. Sugar cane has been grown on the Clarence floodplain for over 125 years and there are over 250 cane farms.
Agricultural and urban development on the coastal floodplain is protected from floods by 110 kilometres of levees and 268 kilometres of publicly managed drains. The investment in these structures is a major public asset.
There is a growing tourist industry focused around water activities such as recreational fishing, swimming, boating and surfing. Tourism contributes more than $100 million annually to the economy of the Clarence Valley. Boating is a major recreational activity, with 90% of recreational boating related to fishing.
Many parts of the Clarence River system are in relatively good condition. Almost half of the catchment is reserved as national parks and state forests. There is a great diversity of vegetation types and wildlife habitats and the catchment is home to many endangered species including the last viable populations of Eastern Freshwater Cod.
Nevertheless, a range of past activities and the current period of rapid development and changes in land use have had, and continue to have, an adverse effect on parts of the river system.