Join Date: Oct 2003
reservoir ops and rain forecast
Hi all--Just sent this out to my e-mail lists:
I have received a few inquiries asking about operations of the Colorado-Big Thompson Project as they relate to the forecast for rain today and tomorrow.
As you all know, the Colorado-Big Thompson Project is not authorized nor designed for flood control. It is a water supply system. Looking at the current forecast, we do not anticipate significant impact to the system. However, we are prepared to respond if conditions change and I will keep you all posted.
Meanwhile, here is a breakdown, by reservoir, of current operations:
At Lake Granby, there is a chance that rain runoff could bring the reservoir back up to 100% full. It is at 99% full, currently. We are still diverting water from Granby via the Adams Tunnel, which is helping keep Granby slightly below full. However, the tunnel is only running at half capacity. As rain runoff inflows come up on the east side of the Divide, we will cut the diversion from the West Slope. Right now, we are projecting it will be curtailed very early tomorrow morning.
Lake Estes is around 82% full--just a touch lower than is typical for this time of year. As West Slope diversions slow down, space in Lake Estes could fill with rain runoff water. We will be able to pull some of that through the C-BT's power arm using the Olympus Tunnel. We've got a little bit of space in Pinewood and Horsetooth reservoirs. But, the remainder of any rain water runoff will have to pass through Olympus Dam to the Big Thompson Canyon.
Right now, outflow through Olympus Dam is around 125 cfs. If the rain materializes as forecast, we could see outflow through Olympus Dam in a range from 125-1200 cfs. This year's spring snow melt runoff through Olympus Dam peaked at about 1195 cfs.
For those in and around the Big Thompson Canyon, here are the links to gages so you can track the rain run off:
Big Thompson River below Olympus Dam
Big Thompson River in Narrows section, near canyon mouth
Please keep in mind that this is all based on forecasts from the National Weather Service and forecasts are subject to change.
I am in all week this week. Please feel free to e-mail or call me with any related questions. As always, please be river wise and river wary!
Eastern Colorado Office
Bureau of Reclamation