River Tay River Tay The River Tay () is the longest river in Scotland and the seventh-longest in the United Kingdom. The Tay originates in western Scotland on the slopes of Ben Lui (), then flows easterly across the Highlands, through Loch Dochart, Loch Iubhair and Loch Tay, then continues east through Strathtay (see Strath), in the centre of Scotland, then southeasterly through Perth, where it becomes tidal, to its mouth at the Firth of Tay, south of Dundee. It is the largest river in the UK by measured discharge. Its catchment is approximately , the Tweed's is and the Spey's is
Tay Bridge disaster allowance for wind loading for spans less than , whilst noting this was for the design of girders not piers. Evidence was taken from scientists on the current state of knowledge on wind loading and from engineers on the allowance they made for it. Airy said that the advice given was specific to suspension bridges and the Forth; could act over an entire span of the Tay Bridge and he would now advise designing to (i.e. with the usual margin of safety). The highest pressure measured at Greenwich was ; it would probably go higher in Scotland. Sir George Stokes