From the Aspen Daily News (Curtis Wackerle):
Beginning in July, the city will empty the reservoir, which stores water for the municipal water treatment plant on Doolittle Drive. It will remain dry for about three months, said Dave Hornbacher, the city’s deputy director of utilities and environmental initiatives…
Most of the $2.3 million 42-inch pipeline, running from the reservoir to the site of the proposed plant, was constructed last summer and fall. Crews still need to install the final 200 feet of pipe leading up to the earthen dam. They will then bore through the dam, build an intake structure and hook up the pipe. The state of Colorado’s Division of Water Resources granted a permit for the work this spring. That permit also requires the city to upgrade a spillway on the east side of the reservoir, so there will be even more capacity to release water form the reservoir in case levels rise too high.
The pipeline is a crucial part of the city’s proposed hydroelectric plant. Voters in 2007 approved $5.5 million in bonds — with a maximum repayment of $10.7 million — to build the plant, which would be located under the Castle Creek Bridge. The pipeline would feed up to 52 cubic feet per second (cfs) of water into a turbine, generating up to 8 percent of the municipal utility’s electricity needs.