From email from Reclamation (Kara Lamb):
First and foremost, the water year on the C-BT is about to wrap up. Halloween is the last day of the 2009 water year for C-BT. That means that some water users are taking the last of their water from the project. Last week, when releases from Olympus Dam to the Big Thompson River increased and when Horsetooth releases out of Horsetooth Dam suddenly increased, it was because water users were taking their last shares of water. Those draws dropped the elevations at Horsetooth and Pinewood. Today, Pinewood is on its way back up and will continue rising through the weekend. Also, we are currently pumping water to Carter Lake, which is also slowly rising–water users are still taking water from Carter. Releases to the Big Thompson have dropped off and will drop again tonight to about 50 cfs in the canyon. That is an average flow for this time of year. Horsetooth is currently at an elevation of 5379. About 50 cfs is flowing to Horestooth. However, demands out of the Big Thompson River have dropped off, at least for the weekend, which means beginning tomorrow morning, we can increase flows to Horsetooth by another 50 cfs. This will level out the current draw of water from Horsetooth, holding the elevation close to 5379, at least for the weekend.
There remains the possibility that water users will call for the very last of their water the last week of the water year. So, it is possible that delivery via the Big Thompson River, or via Horsetooth Reservoir, will be required one more time before the water year closes. If that is the case, late next week we could see flows in the Big T increase, or see an increase in water going out of Horsetooth. Either way, I will keep you posted.
More Colorado-Big Thompson coverage here.