Mill Dam, Shapinsay is a wetland

Wetland

A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....

 in western Shapinsay

Shapinsay

Shapinsay 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...

, in Orkney, Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

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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. Mill Dam is fed by a stream flowing from the north that rises on the western lobe of Shapinsay. The pH

PH

In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...

 levels of the outflow stream of Mill Dam are moderately alkaline, 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

Royal Society for the Protection of Birds

Bird Notes and News was first published in April 1903.The title changed to 'Bird Notes' in 1947. In the 1950s, there were four copies per year . Each volume covered two years, spread over three calendar years...

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