Parteen Villa Weir is sending large amounts of water down the original channel of the Shannon, and over the Falls of Doonass, to draw water off from the upper reaches of the river.
The footbridge at Castleconnell
Above the bridge
The downstream side of the bridge
A bumpy ride
At normal levels the bottom of the wall is several feet above the water
Levels below Parteen Villa have not yet reached those of 2009 and the channel can probably take more before folk get flooded.
The Old River Shannon site has some photos taken at Parteen Villa Weir.
Irish waterways history 
Being on the river in Athlone I can only say that whatever the powers that be are doing appears to be working: the river here is holding just a little short of where things will start getting interesting. And I note from waterlevel.ie that the level at Shannonbridge is also steady at present.
Glad to hear it. The water level in the public harbour at Dromineer was within six inches of the top of the wall last Saturday. The problem may come when the Shannon’s vast catchment drains into the river; I don’t know how much of a rise that might cause. OTOH, Dr William O’Connor thinks that the ESB may be draining too much too fast: see his posts here and here. bjg