In Reply to: river query posted by bob on November 29, 2006 at 20:47:35:

The Moy drainage scheme in the 1960s could have had an impact on the level of the lakes reclaiming land for grazing etc and reducing flooding along the margins - that was the driving force behind the drainage programmes. At low flow times though the lake may have gone too low for fish and wildlife so weirs would control the minimum level in the lake. Removing a few boards would have allowed the level to be dropped in times of high flow. That's not to say that the weirs weren't there long before the drainage scheme.