| Lake Macquarie | |
|---|---|
| View from Swansea showing Pulbah Island | |
| Location | Hunter Region, New South Wales |
| Lake type | Coastal Saltwater |
| Primary inflows | Cockle Creek, Dora Creek |
| Primary outflows | Tasman Sea |
| Basin countries | Australia |
| Max. length | 21.8 km (13.5 mi) |
| Max. width | 7.9 km (4.9 mi) |
| Surface area | 110 km2 (42.5 sq mi) |
| Average depth | 8 m (26 ft) |
| Max. depth | 15 m (49 ft) |
| Shore length1 | 167 km (103.8 mi) |
| Surface elevation | 0 AMSL |
| Frozen | never |
| Islands | Pulbah Island plus several small islands |
| Settlements | City of Lake Macquarie |
| 1 Shore length is not a well-defined measure. | |
Lake Macquarie is Australia's largest coastal salt water lake, covering an area of 110 square kilometres (42.5 sq mi) in the Hunter Region of New South Wales with most of the City of Lake Macquarie's residents living near its shores. It is connected to the Tasman Sea by a short channel. Lake Macquarie is twice as large as Sydney Harbour and is the largest permanent salt water lake in the southern hemisphere. However, it is slightly smaller than Port Stephens, which is about 43 kilometres (27 mi) to the northeast of the lake.
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Lake Macquarie was discovered in 1800 by Captain William Reid, who been sent from Sydney to retrieve a load of coal from Newcastle Harbour. Reid took a wrong turn and found himself in a lake rather than a river, with no coal to be seen anywhere. The name "Reid's Mistake" was retained until 1826, when it was renamed in honour of Governor Lachlan Macquarie.[1] The Aboriginal name was Awaba, which means "a plain surface".[2]
The lake is of irregular shape and the land separating it from the ocean is only a few kilometres wide along most of its length. While there are a several small islands in the lake, some of which are grouped near the mouth, the only significant island is Pulbah Island, which is located in the southern part of the lake south of Swansea.
Lake Macquarie is connected to the sea by Swansea Channel and Lakes Entrance. Swansea Channel is approximately 380 metres (1,247 ft) wide and 2 kilometres (1.2 mi). It joins Lakes Entrance, a small bay measuring approximately 900 m (2,953 ft) wide by 2.2 km (1.4 mi) at the Swansea bridges. The bridges can lift to allow yachts and other larger pleasure craft into and out of the lake.
There is no point on the coast from which the entire expanse of the lake and its 167 km (104 mi) foreshore may be seen. However, a good view can be obtained from lookouts in the nearby Watagan Mountains.
The remnant and fragmented eucalypt forests on the southern margins of the lake have been identified by BirdLife International as a 121 km2 Important Bird Area (IBA) because they support significant numbers of endangered Swift Parrots and Regent Honeyeaters in years when the Swamp Mahoganies and other favoured trees are flowering.[3] Masked Owls and Ospreys regularly nest within the IBA.[4]
Pulbah Island is a small island of approximately 68 hectares (168 acres) in the southern part of the lake at .[5][6] It is a nature reserve managed by the National Parks and Wildlife Service, an agency of the Department of Environment and Climate Change of New South Wales.[5][7] There are no permanent structures on the island and it is uninhabited although in the past a maintenance cottage existed on the Island. Pulbah is an Aboriginal name meaning island.[8]
The island has a lot of weeds such as Bitou Bush, Lantana and Wandering Jew. There have been local efforts to remove and control the weeds. It also has a native trees such as gum trees.
Kangaroos and koalas were introduced to the island during the early 1900s, but they have all since been wiped out by illegal hunting. Goannas are common on the island.
| External images | |
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| Pulbah Island photos | |
From the island there are clear views of the Wangi Wangi peninsula as well as the Eraring, Munmorah and Vales Point power stations.
The island has cliff faces on the west and south sides as well as the south east side. The rest of the island is edged by sandy beaches although the density of vegetation ensures that there is minimal beach at high tide. The east side of the island has a slight bay that is commonly frequented by leisure boats. Camping on the island is not permitted.
In 1983, the State Pollution Control Commission undertook an investigation into the causes of poor water quality in the lake. The final report of this investigation, known as “The Environmental Audit of Lake Macquarie”, identified the primary causes of concern, highlighting the major problems of sedimentation and nutrient enrichment. Accelerated sedimentation levels were estimated at 75,000 tonnes (73,815 long tons) per annum and nutrient levels had shown a substantial increase as a result of urbanisation. A study prepared for Lake Macquarie City Council in 1995 estimated that sediment loads to Lake Macquarie were 57,000 t (56,100 long tons) per annum, which was very different to the sediment loads prior to European development, estimated at 6,600 t (6,496 long tons) per annum. Two creek systems, Cockle and Dora Creeks, were estimated to be contributing 23,900 t (23,523 long tons) and 11,000 t (10,826 long tons) per annum respectively.[9]
In 1998, the then Premier of NSW, the Hon. Bob Carr, announced the formation of a task force under the chairmanship of Clean Up Australia founder, Ian Kiernan. The report of the task force, known as the "Integrated Estuary and Catchment Management Framework" was accepted by the NSW State Cabinet in February 1999. The report recommended a unique institutional arrangement for implementation through the creation of the Office of the Lake Macquarie and Catchment Coordinator. This cooperative-based arrangement was a joint initiative of Lake Macquarie City Council, Wyong Shire Council, and the State Government, with major funding provided by these partners. To oversee the implementation process, a committee known as the Lake Macquarie Project Management Committee was appointed by the then Minister of Land and Water Conservation. The Committee would consist of representatives of both councils; community; regional directors of relevant government departments and three ex-officio members.[10]
The action plan, known locally as the "Lake Macquarie Improvement Plan" has an emphasis on integration, both physically and administratively, as well as promoting a "whole of government" approach and strong community involvement. The physical works concentrated on treating the cause of the water problems in the Lake by tackling stormwater runoff within the catchment. Again, the emphasis adopted included the use of "soft engineering" and the restoration of natural ecological processes where possible.
After six years in operation, the Lake Macquarie Project Management Committee entered its third project phase in 2006.[11]
A series of water quality indicators are used to monitor and quantify the water quality improvements observed by the community. The lake body generally has low nutrient concentrations, good water clarity and excellent dissolved oxygen levels.[12] Activities that reduce the amount of sediments and nutrients washing into the Lake via stormwater run-off have assisted in improving water quality in Lake Macquarie. These activities include the construction of wetlands, the installation of stormwater treatment devices, bush regeneration and an increased awareness by the local community.[13]
Recreational fishing is improving as fish stocks respond to the recent removal of commercial fishing and the significant increase in water quality that has come from a concerted environmental program undertaken by the state government and council. Since settlement lake-bed silt has increased in some areas due to unsealed roads, road shoulders and diffuse effects of urbanisation, however the quantity is far less than in nearby Lake Munmorah, and swimming is quite tolerable. Average water depth is approximately 8 m (26 ft) reaching a maximum depth of approximately 15 m (49 ft) east of Pulbah Island.
Recreational fishing, boating and water skiing are all popular recreational activities on the lake. Sailing and yacht racing are also popular with the lake boasting multiple yacht clubs including:
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