Rocky Creek Dam
Encyclopedia
Rocky Creek Dam is a drinking water catchment dam on the North Coast of New South Wales
, Australia
. The dam forms the waterbody known as Rocky Lake. As the principal source for Rous Water it supplies water for the majority of the Far North Coast of New South Wales including Lismore
, Ballina
, Byron Bay, Evans Head and Alstonville.
and Whian Whian State Conservation area. The area was once used for logging but is now has a conserved and generally pristine catchment environment for the North Coast of New South Wales.
The vegetation in the catchment is mainly subtropical rainforest or wet sclerophyll. The vegetation community generally reflects the geology and soils in the area which are derived from the Lamington Volcanics which in this area consists of basalt
and thick rhyolite
rocks erupted from the Tweed Volcano
. The subtropical rainforest is generally regarded as one of the biggest remnants of the Big Scrub
rainforest that once existed over a large part of the surrounding region.
In 2009 the dam wall was upgraded. This upgrade did not increase the height of the dam wall or increase the volume of water stored behind the dam, it was focused on ensuring the safety of the dam wall during a maximum probable flood. The upgrade involved the removal of the top of the wall, the installation of a concrete cut-off wall
keyed into the impermeable clay core, followed by replacement of the gravel and road over the dam wall. Actual construction works took approximately three months.
) and interpretive walks. The lawns near the edge of the lake are often used for weddings.
The catchment is mainly under the control of the National Parks and Wildlife Service
as National Parks
and State Conservation areas
. This means that only passive recreation such as bush walking, bird watching, etc are permitted. However, Swimming, boating, 4WD and dirt bikes are prohibited in the catchment area.
, Ballina
, Byron Bay
, Evans Head
, and Lismore
. Water is pumped from the lake a short distance to the Nightcap Water Treatment Plant and then this water is provided to the region generally through gravity reticulation.
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. The dam forms the waterbody known as Rocky Lake. As the principal source for Rous Water it supplies water for the majority of the Far North Coast of New South Wales including Lismore
Lismore, New South Wales
Lismore is a subtropical town in northeastern New South Wales, Australia. Lismore is the main population centre in the City of Lismore local government area. Lismore is a regional centre in the Northern Rivers region of the State.-History:...
, Ballina
Ballina, New South Wales
Ballina is a town on the Northern Rivers of New South Wales, Australia, and the seat of the Ballina Shire Local Government Area. It had a population of 16,477 in the 2006 Census.-Location:...
, Byron Bay, Evans Head and Alstonville.
Catchment
The Rocky Creek Dam catchment is made up of 31 km² which includes the Whian Whian State Forest, Nightcap National ParkNightcap National Park
Nightcap National Park is in New South Wales, Australia, 35 km north of Lismore. It is classed by the IUCN World Commission on Protected Areas as Category II...
and Whian Whian State Conservation area. The area was once used for logging but is now has a conserved and generally pristine catchment environment for the North Coast of New South Wales.
The vegetation in the catchment is mainly subtropical rainforest or wet sclerophyll. The vegetation community generally reflects the geology and soils in the area which are derived from the Lamington Volcanics which in this area consists of basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
and thick rhyolite
Rhyolite
This page is about a volcanic rock. For the ghost town see Rhyolite, Nevada, and for the satellite system, see Rhyolite/Aquacade.Rhyolite is an igneous, volcanic rock, of felsic composition . It may have any texture from glassy to aphanitic to porphyritic...
rocks erupted from the Tweed Volcano
Tweed Volcano
Tweed Volcano was an early Miocene shield volcano in northeastern New South Wales, Australia. In the course of about three million years, Tweed Volcano was formed over the East Australia hotspot when this part of the continent passed over it around 23 million years ago...
. The subtropical rainforest is generally regarded as one of the biggest remnants of the Big Scrub
Big Scrub
The Big Scrub was the largest area of subtropical lowland rainforest in eastern Australia. It was intensively cleared for agricultural use in the 19th century by colonists...
rainforest that once existed over a large part of the surrounding region.
Construction
The dam itself covers around two square kilometres (478 acres) and can hold about 14,000 mega litres of water when at 100% capacity. The dam wall is 28 metres high and is made up of about 80,000 tonnes of rock, soil, clay and concrete. Construction of the dam and spillway was completed in 1953.In 2009 the dam wall was upgraded. This upgrade did not increase the height of the dam wall or increase the volume of water stored behind the dam, it was focused on ensuring the safety of the dam wall during a maximum probable flood. The upgrade involved the removal of the top of the wall, the installation of a concrete cut-off wall
Slurry wall
A slurry wall is a technique used to build reinforced-concrete walls in areas of soft earth close to open water or with a high ground water table. This technique is typically used to build diaphragm walls surrounding tunnels and open cuts, and to lay foundations.A trench is excavated to create a...
keyed into the impermeable clay core, followed by replacement of the gravel and road over the dam wall. Actual construction works took approximately three months.
Recreation
Recreation (including swimming and boating) on the lake itself is prohibited to protect the high quality of the water in the dam. However, a recreational area is provided by Rous Water near the dam wall including lawns, barbecues, playgrounds, walking tracks (including a board walk and pontoon bridgePontoon bridge
A pontoon bridge or floating bridge is a bridge that floats on water and in which barge- or boat-like pontoons support the bridge deck and its dynamic loads. While pontoon bridges are usually temporary structures, some are used for long periods of time...
) and interpretive walks. The lawns near the edge of the lake are often used for weddings.
The catchment is mainly under the control of the National Parks and Wildlife Service
National Parks and Wildlife Service (New South Wales)
The National Parks and Wildlife Service is part of the Office of Environment and Heritage - the main government conservation agency in New South Wales, Australia....
as National Parks
National park
A national park is a reserve of natural, semi-natural, or developed land that a sovereign state declares or owns. Although individual nations designate their own national parks differently A national park is a reserve of natural, semi-natural, or developed land that a sovereign state declares or...
and State Conservation areas
Protected areas of New South Wales
The Protected areas of New South Wales include both terrestrial and aquatic protected areas. At 30 June 2010 there were 776 separate terrestrial protected areas with a total land area of . 189 of these are national parks, totalling...
. This means that only passive recreation such as bush walking, bird watching, etc are permitted. However, Swimming, boating, 4WD and dirt bikes are prohibited in the catchment area.
Water supply
Water from the lake is used as a potable water supply by Rous Water to the region. It is the primary water source to the centres of AlstonvilleAlstonville, New South Wales
Alstonville is a town located in northern New South Wales, Australia, part of the region known as the Northern Rivers. Alstonville is located on the Bruxner Highway between the town of Ballina and city of Lismore . The village of Wollongbar is situated 4 km to the west of Alstonville...
, Ballina
Ballina, New South Wales
Ballina is a town on the Northern Rivers of New South Wales, Australia, and the seat of the Ballina Shire Local Government Area. It had a population of 16,477 in the 2006 Census.-Location:...
, Byron Bay
Byron Bay, New South Wales
Byron Bay is a beachside town located in the far-northeastern corner of the state of New South Wales, Australia. It is located north of Sydney and south of Brisbane. Cape Byron, a headland adjacent to the town, is the easternmost point of mainland Australia. At the 2006 Census, the town had a...
, Evans Head
Evans Head, New South Wales
Evans Head is a town in the Northern Rivers region of New South Wales, Australia in Richmond Valley Shire. At the 2006 census, Evans Head had a population of 2,631 people. It is 726 kilometres north of Sydney, and 11 kilometres east off the Pacific Highway from Woodburn...
, and Lismore
Lismore, New South Wales
Lismore is a subtropical town in northeastern New South Wales, Australia. Lismore is the main population centre in the City of Lismore local government area. Lismore is a regional centre in the Northern Rivers region of the State.-History:...
. Water is pumped from the lake a short distance to the Nightcap Water Treatment Plant and then this water is provided to the region generally through gravity reticulation.