ESB Networks today increased the flow at the Inniscarra Dam on the River Lee.
The flow at the Parteen Weir at Lough Derg is also being monitored, and could be increased in the coming days.
Engineering manager with the ESB Tom Browne, explains why they've taken the decision to increase the flow rates at those weirs.
"Well what would happen if you didn't do it basically is the level in Lough Derg would back up.
"Ultimately you will get significant flooding upstream, but more importantly you would also be creating a significant risk downstream then because effectively you would be giving yourself a lot less room to manoeuvre if further heavy rains come."