The Chimney Hollow valve house at the downstream toe of the main dam is well underway. It will be approximately 14,400 square feet, four stories tall and will control pressures and flows between the Colorado-Big Thompson (C-BT) Project and Chimney Hollow Reservoir.  In the next couple of months, all concrete will be poured, and miscellaneous items, like walkways and platforms, will be complete. By the end of June, all the valves and piping will be installed. After that, crews will begin working on the actual building, which will take about a year to construct.