| Six Mile Creek Dam | |
| Location Map: | Queensland |
| Location Map Caption: | Location of the Six Mile Creek Dam in Queensland |
| Coordinates: | -26.3811°N 152.93°W |
| Country: | Australia |
| Location: | South East Queensland |
| Status: | O |
| Operator: | SEQ Water |
| Dam Type: | E |
| Dam Height: | 15.7m (51.5feet) |
| Dam Length: | 490m (1,610feet) |
| Dam Volume: | 69e3m3 |
| Dam Crosses: | Six Mile Creek |
| Spillway Type: | Uncontrolled |
| Spillway Capacity: | 1147m3/s |
| Res Name: | Lake Macdonald |
| Res Capacity Total: | 8018ML[1] |
| Res Catchment: | 49km2 |
| Res Surface: | 260ha |
The Six Mile Creek Dam (more commonly known as Lake MacDonald) is a rock and earth-fill embankment dam with an un-gated spillway across the Six Mile Creek that is located in the South East region of Queensland, Australia. The main purposes of the dam are for potable water supply of the Sunshine Coast region and for recreation.[2] The impounded reservoir is called Lake Macdonald, named in memory of former Noosa Shire Council Chairman Ian MacDonald.[3]
The dam is located from Cooroy and west of Noosa. The small settlement of is located adjacent to the dam. The primary inflow of the reservoir is Six Mile Creek.
Built in 1965[2] and raised by 3.6 metres in 1980, the rock and earthfill dam structure is high and long. The 69e3m3 dam wall holds back the 8018ML reservoir when at full capacity. From a catchment area of that includes much of the Tewantin National Park, the dam creates Lake Macdonald, with a surface area of . The uncontrolled un-gated spillway has a discharge capacity of .[2] [4] Initially managed by the Sunshine Coast Regional Council, management of the dam was transferred to Seqwater on 1 July 2008.
The dam reached its maximum recorded level of 1.97m over the spillway in February 2012.
In May 2019, Seqwater proposes to upgrade Six Mile Creek Dam (also known as Lake Macdonald Dam) as part of its Dam Improvement Program.[5]
Within proximity of the dam, horse riding, boating and canoeing are permitted. The Noosa Botanic Gardens are located on the northwestern shoreline of Lake Macdonald.
The reservoir is stocked with Mary River cod, bass, yellowbelly, saratoga and snub nosed gar with endemic populations of tandans (eel tailed catfish) and the introduced spangled perch.[6] [7] A stocked impoundment permit is required to fish in the dam.[8]
Historical high water capacity percentages above 110% since recording began on 1 July 2008.[9]
| Date | Percentage | |
|---|---|---|
| 1 November 2017 | 113.4 | |
| 8 October 2018 | 115.3 | |
| 1 November 2020 | 119.9 | |
| 14 February 2022 | 111.6 | |
| 16 May 2022 | 113.4 | |
| 30 January 2024 | 115.2 |