I was looking this up and thought I could expand a wee bit on an explanation of the Mickey Dam.
It refers to the Mugdock Reservoir in Milngavie just north of my house which is a terrific feat of Victorian engineering fro the late 19th century. The reservoir is connected to Loch Katrine in the Trossachs and has supplied the City of Glasgow with water since then.
Like most project of this era the workers would come from Ireland hence the title.