There is a television series called Building Ireland, about “Ireland’s building and engineering heritage”. A series of six programmes will begin on Friday 30 September 2016 at 8.30pm on RTÉ One, which is a television station.
The third programme, on 14 October, covers Ardnacrusha and the sixth, on 4 November, is entitled “Galway’s Corrib Canal” and covers canals in Galway and, I believe, may have some material about the Cong Canal.
Here is a PDF describing the series.
building-ireland-series-info-and-billings
Irish waterways history 