Crews Make Significant Progress on the Testing of Chimney Hollow Infrastructure
The testing and commissioning of the infrastructure that will ultimately bring water into the Chimney Hollow Reservoir Project is well underway. Crews are making significant progress pushing us closer to seeing water flow into the future reservoir.
About 90 percent of the dry (testing valves and pipes without water) and leakage testing is done – all that remains is the testing of the valves and pipes in the tunnel. The fiberoptic system has been tested, and Northern Water crews are starting to install equipment in the valve house that will connect the operating system of Chimney Hollow to the rest of the Colorado-Big Thompson Project.
In early- to mid-June, crews will wet test various valves in the valve house, which is the same testing that was performed previously without water. Crews will also perform a dry test of the bulkhead, which will be placed between the inlet/outlet tower and the pipe that carries water in and out of the reservoir. When work needs to be performed on the inlet/outlet tunnel piping, crews will place the bulkhead from a floating barge in the reservoir to stop the water from flowing into the pipe that needs to be inspected or repaired.
At the end of June, crews will test the power systems and the saddle dam instrumentation. In early July, dry and wet testing of the hydraulic power unit (HPU), which houses the hydraulic system that can close key valves in the case of a power outage, as well as testing the conduit from the valve house through the tunnel to the inlet/outlet tower, will be completed. By late July, all of the main dam instrumentation will be tested.
Following testing and commissioning of all components, water will begin flowing into the reservoir in late summer.
