Cotter River
Encyclopedia
The Cotter River is a fresh water river
in the Australian Capital Territory
. It is a tributary
of the Murrumbidgee River
and part of Murray-Darling Basin
. The Cotter River is one of two rivers—the Queanbeyan River is the other—that meet the water supply
needs of the Canberra and Queanbeyan
region. The river is named after a colonial convict Garrett Cotter
who first settled and had a very long and continued association with the Cotter River region in the mid 19th century.
When the Government surveyor, Charles Scrivener
, recommended Canberra as the best site for Australia's national capital, water catchment
was a significant consideration. Of the total 2358 square kilometre of the Australian Capital Territory, 480.1 square kilometre were reserved as the catchment area of the Cotter River. The catchment area was calculated to support a planned population of 100,000.
. Most of the Cotter catchment is in the Namadgi National Park
.
The Cotter Dam is currently having a new 76m dam wall built downstream of the current 26m dam wall, along with a couple of auxiliary dam walls along low-lying neighbouring valleys. This will increase storage capacity of the Cotter Dam from the current 3.9GL to 78GL. The old dam wall will remain and be inundated during extended periods of average to above average rainfall. Completion is expected in June 2012 .
The Cotter Dam, like other dams and reservoirs within the Cotter Catchment supply domestic drinking water and is therefore closed to recreational watercraft use. The Cotter River Reserve located at the base of the dam wall is a very popular picnic
area. The reserve has amenities such as barbecue
facilities and tables. There are a number of areas that are suitable for swimming when there is sufficient water flowing in the river. There is also a short term camping site which can accommodate a very limited number of caravans and tents.
The Cotter Road, ACT tourist route 5, begins as a side road off Adelaide Avenue in the suburb of Deakin. The scenic drive stretches 17.6km from the centre of Canberra past the suburbs of Curtin, Holder and Duffy, in between Stromlo Forest and Narrabundah Hill Pine Plantation, and past Casuarina Sands into the Cotter Avenue river area. "The Cotter" and the adjoining 7.1km winding Brindabella Road (the beginning of "The Loop") are well known to motorcyclists, many of whom ride there in the evening after work or on weekends. The Cotter Hotel, which stood near the children's swings alongside the river, was burned down in the 2003 bushfires
. It was a well known meeting place amongst motorcyclists on weekends.
The upper section of the Cotter River is also popular with white water kayakers. Featuring a fast flowing scenic grade 3 section. However the river requires high rainfalls for it to flow at a minimum level. There has been a push by local white water paddlers to kayak this section before the dam is completed down stream as it raise the level of the lake drowning the section. Below the dam are also kayaking opportunities. Located near the top picnic area the 'Cotter Play Wave' is the only one in the area and creates playboating opportunities formed by a small weir, however again it requires high flows. From the play wave it is possible to paddle to the confluence of the Murrumbidgee River. Caution is advised as it is prone to strainers formed by trees, weirs and man made objects.
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...
in the Australian Capital Territory
Australian Capital Territory
The Australian Capital Territory, often abbreviated ACT, is the capital territory of the Commonwealth of Australia and is the smallest self-governing internal territory...
. It is a tributary
Tributary
A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...
of the Murrumbidgee River
Murrumbidgee River
The Murrumbidgee River is a major river in the state of New South Wales, Australia, and the Australian Capital Territory . A major tributary of the Murray River, the Murrumbidgee flows in a west-northwesterly direction from the foot of Peppercorn Hill in the Fiery Range of the Snowy Mountains,...
and part of Murray-Darling Basin
Murray-Darling Basin
The Murray-Darling basin is a large geographical area in the interior of southeastern Australia, whose name is derived from its two major rivers, the Murray River and the Darling River. It drains one-seventh of the Australian land mass, and is currently by far the most significant agricultural...
. The Cotter River is one of two rivers—the Queanbeyan River is the other—that meet the water supply
Water supply
Water supply is the provision of water by public utilities, commercial organisations, community endeavours or by individuals, usually via a system of pumps and pipes...
needs of the Canberra and Queanbeyan
Queanbeyan, New South Wales
Queanbeyan is a regional centre in the Southern Tablelands in south-eastern New South Wales adjacent to the Australian Capital Territory. The city's mixed economy is based on light construction, high technology, manufacturing, service, retail and agriculture. It is the council seat of the...
region. The river is named after a colonial convict Garrett Cotter
Garrett Cotter
Garrett Cotter was an Australian convict. The Cotter River in the Australian Capital Territory is named after him.From circa 1827, Garret Cotter inhabited the Cotter Valley and the Cotter River received its name by association. Cotter was born in 1802 in County Cork. He had been a ploughman and...
who first settled and had a very long and continued association with the Cotter River region in the mid 19th century.
When the Government surveyor, Charles Scrivener
Charles Scrivener
Charles Robert Scrivener was an Australian surveyor, and the person who surveyed numerous sites in New South Wales for the selection of a site for the Australian Capital Territory and Australia's capital city, Canberra....
, recommended Canberra as the best site for Australia's national capital, water catchment
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
was a significant consideration. Of the total 2358 square kilometre of the Australian Capital Territory, 480.1 square kilometre were reserved as the catchment area of the Cotter River. The catchment area was calculated to support a planned population of 100,000.
Dams
There are three reservoirs on the river, the Corin, Bendora and Cotter Dams which supply water to CanberraCanberra
Canberra is the capital city of Australia. With a population of over 345,000, it is Australia's largest inland city and the eighth-largest city overall. The city is located at the northern end of the Australian Capital Territory , south-west of Sydney, and north-east of Melbourne...
. Most of the Cotter catchment is in the Namadgi National Park
Namadgi National Park
Namadgi National Park is located in the southwestern part of the Australian Capital Territory, bordering Kosciuszko National Park in New South Wales. It lies approximately 40 km southwest of Canberra, and makes up approximately 46% of the ACT's land area....
.
- Cotter Dam is a concrete gravity dam built in 1912 when the city of Canberra was established. The height of the dam wall was raised in 1951 to increase capacity. The top water level of the dam is 501m above sea level. The dam has a capacity of 3,856 million litres; a review in October 2006 using more accurate mapping methods resulted in capacity being re-estimated downwards from the previous estimate of 4,700 million litres. Water was pumped from the dam to Mount StromloMount StromloMount Stromlo is situated a short drive west of the centre of Canberra, Australia, near the district of Weston Creek. Its peak is at approximately 770m AHD....
and from there the water flowed by gravity to fill the city's reservoirs. The dam water quality had deteriorated compared with Bendora and Corin dams and the dam was only used when water is in short supply. However, in December 2004, ActewAGLActewAGLActewAGL is Australia's first multi-utility to offer electricity, natural gas, water and wastewater services in a single organisation. At the time of its formation it was the only multi-utility of its kind in Australia....
brought the dam back on line in response to the ongoing droughtDrought in AustraliaDrought in Australia is defined as rainfall over a three month period being in the lowest decile of what has been recorded for that region in the past. This definition takes into account that drought is a relative term and rainfall deficiencies need to be compared to typical rainfall patterns...
.
The Cotter Dam is currently having a new 76m dam wall built downstream of the current 26m dam wall, along with a couple of auxiliary dam walls along low-lying neighbouring valleys. This will increase storage capacity of the Cotter Dam from the current 3.9GL to 78GL. The old dam wall will remain and be inundated during extended periods of average to above average rainfall. Completion is expected in June 2012 .
- Bendora DamBendora DamThe Bendora Dam is a thin-wall, double curvature concrete dam, completed in 1961 on the Cotter River in the Australian Capital Territory to supply water to Canberra, via the Bendora Gravity Main. It was the first dam of its type built in Australia. It is 47.2 metres high.-References:* Canberra's...
, a double curvature concrete arch dam completed in 1961. It has a capacity of 11,540 million litres. The top water level of the dam is 778m above sea level. - Corin Dam, an earth and rockfill embankment damEmbankment damAn embankment dam is a massive artificial water barrier. It is typically created by the emplacement and compaction of a complex semi-plastic mound of various compositions of soil, sand, clay and/or rock. It has a semi-permanent waterproof natural covering for its surface, and a dense, waterproof...
with a capacity of 70,900 million litres. This dam which was completed in 1967 is situated upstream of the Bendora Dam and controls the release of water into Bendora Dam. The top water level of the dam is 956m above sea level.
Recreation
Picnic
In contemporary usage, a picnic can be defined simply as a pleasure excursion at which a meal is eaten outdoors , ideally taking place in a beautiful landscape such as a park, beside a lake or with an interesting view and possibly at a public event such as before an open air theatre performance,...
area. The reserve has amenities such as barbecue
Barbecue
Barbecue or barbeque , used chiefly in the United States, Canada, the United Kingdom, New Zealand and Australia is a method and apparatus for cooking meat, poultry and occasionally fish with the heat and hot smoke of a fire, smoking wood, or hot coals of...
facilities and tables. There are a number of areas that are suitable for swimming when there is sufficient water flowing in the river. There is also a short term camping site which can accommodate a very limited number of caravans and tents.
The Cotter Road, ACT tourist route 5, begins as a side road off Adelaide Avenue in the suburb of Deakin. The scenic drive stretches 17.6km from the centre of Canberra past the suburbs of Curtin, Holder and Duffy, in between Stromlo Forest and Narrabundah Hill Pine Plantation, and past Casuarina Sands into the Cotter Avenue river area. "The Cotter" and the adjoining 7.1km winding Brindabella Road (the beginning of "The Loop") are well known to motorcyclists, many of whom ride there in the evening after work or on weekends. The Cotter Hotel, which stood near the children's swings alongside the river, was burned down in the 2003 bushfires
2003 Canberra bushfires
The Canberra bushfires of 2003 caused severe damage to the outskirts of Canberra, the Australian capital city. Almost 70% of the Australian Capital Territory’s pasture, forests and nature parks were severely damaged, and most of the renowned Mount Stromlo Observatory was destroyed...
. It was a well known meeting place amongst motorcyclists on weekends.
The upper section of the Cotter River is also popular with white water kayakers. Featuring a fast flowing scenic grade 3 section. However the river requires high rainfalls for it to flow at a minimum level. There has been a push by local white water paddlers to kayak this section before the dam is completed down stream as it raise the level of the lake drowning the section. Below the dam are also kayaking opportunities. Located near the top picnic area the 'Cotter Play Wave' is the only one in the area and creates playboating opportunities formed by a small weir, however again it requires high flows. From the play wave it is possible to paddle to the confluence of the Murrumbidgee River. Caution is advised as it is prone to strainers formed by trees, weirs and man made objects.
External links
- ACTEW Corporation. Future Water Options
- Ecological effects of serial impoundment on the Cotter River, Australia
- High-resolution total stream power estimates for the Cotter River, Namadgi National Park, Australian Capital Territory
- State of the Environment Report 2003 Australian Capital Territory Indicator: water use