Colorado Public Works Journal, Fall 2022

Fall 2022 15 On February 19, 2021, the Sky Ridge Bridge (Lone Tree Structure 4) was struck by an over height excavator which was being transported on a flatbed trailer on I-25. The excavator arm struck the exterior concrete bulb tee girder and severed 14 post tensioned strands making up 35% of the strands in the girder. The City of Lone Tree, CDOT, FHWA and emergency personnel responded immediately resulting in a full closure of northbound I-25 for several hours while emergency inspections were performed. The inspection findings and recommendations resulted in a need to replace the girder. The City then contracted with WSP to use Benesch’s findings to begin a design to safely remove and replace the damaged girder. The City, WSP and CDOT worked together to prepare an emergency design repair package and started discussions with contractors within 2 months. Final design packages, CDOT IGA and contractor bidding occurred within 3 months of the bridge strike. Kraemer North America was selected as the contractor and was able to mobilize within days after being selected. Partial demolition and construction occurred over the next 3 months which included numerous interstate closures overnight and lane shifts. This project required close coordination with the City of Lone Tree, CDOT, FHWA, Rampart Range Metropolitan District, RTD, nearby businesses and all the contractors and material suppliers. A project this size would normally span 18 months and was condensed because of the close collaboration of all entities. The Sky Ridge Bridge emergency repair project was a successful collaboration of numerous stakeholders achieving a complex girder replacement on a bridge spanning mainline I-25. The cooperation and attention from all parties allowed the project to be completed within 7 months of the damage and with as little disruption to the public as possible. This is truly a success story ºin forging and utilizing relationships to deliver a critical project. City of Lone Tree - Sky Ridge Bridge Emergency Repair Project SMALL COMMUNITY DISASTER OR EMERGENCY CONSTRUCTION VALUE FOCUSED. COMMUNITY MINDED. QUALITY DRIVEN. Congratulations to the City of Lone Tree for the collaborative e ort on the Sky Ridge Bridge Emergency Repair Project Winner of the APWA Disaster or Emergency Construction, Repair or Response – Small Community Award