From email from Reclamation (Kara Lamb):
It is almost spring and that means we are in the middle of filling both Horsetooth and Carter reservoirs for the upcoming season.
For the last six weeks, we have been sending water into Horsetooth Reservoir at a rate of about 500 cfs. Those tracking the reservoir’s progress will note that it reached a water level elevation of just over 5400 feet earlier this week. Currently, it is sitting at almost 5403–about 11 feet down from where we typically start the water season. However, we are hoping to fill Horsetooth a little more than that, this year.
While we have been filling Horsetooth, Carter Lake has remained at a water level elevation of 5744–about 15 vertical feet from full. Because our goal is to have both Horsetooth and Carter at their highest elevation for the season by mid-May, it is time to resume pumping water to Carter. This means on Monday afternoon (March 8, 2010), we will once again begin pumping water into Carter Lake.
When we are pumping to Carter, we cannot send as much water into Horsetooth. Once the pump to Carter goes on, inflow to Horsetooth will drop to around 165 cfs. We anticipate we will fill Carter through the month of March, resuming our fill of Horsetooth by the second week of April. Both reservoirs are anticipated to reach their highest water level elevation for the season by the middle of May.