http://www.bbc.co.uk/iplayer/episode/b06jsxbk/tryweryn-50-years-on

Available on BBC iPlayer for a limited period.   It is stated that this dam led to concessions for Wales: the DVLA in Swansea, a Secretary of State for Wales and the Welsh Assembly.   Ironically, Liverpool did not need the water because it was aleady exporting some to other districts.  They simply wanted to increase their resources - and of course their profits.  It was another case of greed and not need.

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