Colorado's Tallest Dam Was Built Over a 70-Year-Old Dam. Mega Construction Projects

How do engineers raise a working dam 131 feet without draining the lake behind it? In Colorado, the Gross Dam expansion transforms a 340-foot gravity dam into a 471-foot arch structure, aiming to triple reservoir storage and strengthen Denver’s water supply. See canyon blasting, 37-ton concrete cuts, 20,000-psi water jets, rock grouting, roller-compacted concrete, giant conveyors, and construction of a stepped spillway designed to control floodwater. Then follow the water beyond the dam through a gravity-fed mountain siphon, massive pipelines, treatment plants, water reuse, underground storage, and high-tech pipe inspections. This extreme engineering documentary reveals how dam construction and America’s water infrastructure work together—and why bigger reservoirs are only one part of solving drought. Video Chapters: 0:00 — How Colorado Raised a Working Dam Higher 1:57 — Why Denver Needed Three Times More Storage 3:32 — Cutting Old Concrete and Preparing Canyon Foundations 5:29 — Testing and Placing Giant Layers of Concrete 7:30 — Bonding Old and New Dam Concrete Together 9:19 — Controlling Dangerous Floodwater With Massive Spillway Systems 11:55 — Moving Mountain Water Across Valleys Without Pumps 13:34 — Recycling Water and Exploring Underground Storage Systems 15:03 — Inspecting Aging Pipelines and Protecting Denver's Supply Hashtags: #DamConstruction #ExtremeEngineering #MegaConstruction #GrossDam #Colorado #CivilEngineering #DamEngineering #WaterInfrastructure #EngineeringDocumentary #ReservoirConstruction #FloodControl #MegaProjects --------------------------------- ⚠️ Copyright Disclaimers • We use images and content by the YouTube Fair Use copyright guidelines • Section 107 of the U.S. Copyright Act states: “Notwithstanding the provisions of sections 106 and 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright.” • This video could contain certain copyrighted video clips, pictures, or photographs that were not specifically authorized to be used by the copyright holder(s), but which we believe in good faith are protected by federal law and the fair use doctrine for one or more of the reasons noted above.