From the Summit County Citizens Voice (Bob Berwyn):
The trans-mountain Roberts Tunnel, which transports water from Dillon Reservoir to the South Platte drainage, will remain shut off until April while Denver Water does major maintenance on the valves at the east end of the underground aqueduct…
“We’re in the process of draining it right now,” Steger said. The original plan was to shut off the tunnel in early November, but after talks with Keystone Ski Area, which uses some of the water from the tunnel for snowmaking, Denver Water decided to hold off on the project until mid-December, toward the end of the snowmaking season.
More Denver Water coverage here.