![Mill Dam RSPB wetlands, extreme northern verge, Shapinsay](https://upload.wikimedia.org/wikipedia/commons/f/f2/Mill_Dam_RSPB_wetlands%2C_extreme_northern_verge%2C_Shapinsay.jpg)
Mill Dam is a
wetland
A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...
in western
Shapinsay
Shapinsay (, sco, Shapinsee) is one of the Orkney Islands off the north coast of mainland Scotland. There is one village on the island, Balfour, from which roll-on/roll-off car ferries sail to Kirkwall on the Orkney Mainland. Balfour Castle ...
, in Orkney,
Scotland
Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the ...
.
This water body was not shown on the 1840 survey map of the island, since it is a man-made creation from a damming in the 1880s.
[G.T, Masters, ''Orkney, Approaches to Kirkwall'', HMS official survey map, 1840-1843] Mill Dam is fed by a stream flowing from the north that rises on the western lobe of Shapinsay. The
pH levels of the outflow stream of Mill Dam are moderately
alkaline
In chemistry, an alkali (; from ar, القلوي, al-qaly, lit=ashes of the saltwort) is a base (chemistry), basic, ionic compound, ionic salt (chemistry), salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as ...
, in the range of 9.18. The Mill Dam wetland is a significant bird habitat and is owned and managed by the
Royal Society for the Protection of Birds
The Royal Society for the Protection of Birds (RSPB) is a charitable organisation registered in England and Wales and in Scotland. It was founded in 1889. It works to promote conservation and protection of birds and the wider environment throug ...
.
See also
*
Balfour Castle
Balfour Castle is a historic building on the southwest of Shapinsay, Orkney Islands. Though built around an older structure that dates at least from the 18th century, the present castle was built in 1847, commissioned by Colonel David Balfour, ...
*
Burroughston Broch
Burroughston Broch is an Iron Age broch located on the island of Shapinsay in the Orkney Islands, in Scotland (). The site overlooks the North Sea on the northeast part of Shapinsay. Excavated in the mid 19th century, Burroughston Broch is stil ...
*
The Ouse
The Ouse is a tidal estuary in northern Shapinsay, Orkney Islands. This water body has been shown on early maps of the island in a very similar shape to its current geometry. The Ouse is fed by small rivulets and upland springs that rise on the ...
*
Vasa Loch
Vasa Loch is a brackish lagoon in southwestern Shapinsay, Orkney Islands. (Ordnance, 2002) This water body has been shown on early maps of the island in a very similar shape and size to its current geometry, separated from the North Sea by a narr ...
Footnotes
External links
Shapinsay Island, Orkney
Dams in Scotland
Wetlands of Scotland
Landforms of Orkney
Shapinsay
Royal Society for the Protection of Birds reserves in Scotland
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