Just to let you know, I've set up a Facebook page for Olympus Dam and Lake Estes.
I wanted to create a place people can go to get correct information about Olympus Dam, how it operates, and why. Feel free to post questions there, or here, or send them to me directly. I'll answer as best I can.
As for what to expect for run-off: I just don't have enough information yet. True, March is almost over, but April is traditionally our second largest precip month of the year. We wait until the May 1 forecast before we finalize our own operation plans.
But, Deep South Paddler is correct: During run-off, if there is enough water native to the Big Thompson, we do divert it through the Olympus Tunnel to generate power and then redeliver it to the Big Thompson at the Canyon Mouth.
Most days, though, roughly 98% of the water in Lake Estes is actually Colorado River water, delivered there via the Colorado-Big Thompson water diversion project. We usually move all C-BT project water through Olympus Tunnel. Only when we have portions of the project down for maintenance do we release C-BT Project water through Olympus Dam.
Olympus Dam is really just a diversion dam. It catches the C-BT water and redirects it through the rest of the project, to power plants, Horsetooth and Carter reservoirs. The Dam is always bypassing native Big Thompson River water right on through to the canyon. It is not designed for flood control, so large native flows have to be passed on through. We don't have any place else to put them.
Come the first week of May, we'll have a much better idea of how we'll balance run-off and C-BT project imports. I will definitely keep you all posted.