Rotten Calder

The Rotten Calder is a river to the east of East Kilbride, South Lanarkshire, Scotland and along with the Rotten Burn it forms the southern and western boundaries of Blantyre.

It begins as the Calder Water at its source at Ardochrig, and is joined by the Cleughearn, Lea and Drumloch Burns around Langlands Moss which drain from the Eldrig Hills. This river has also been titled the 'West' or 'South Calder Water', although the latter title is shared by another river in Motherwell. Upon being joined by the Rotten Burn to the south-east of East Kilbride, the river becomes the Rotten Calder Water. 'Water' is a term used in Scotland to denote a small river.

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