This complex rehabilitation project completed in 2020 involved the completion of repairs and improvements to Sylvan Lake Dam, a high hazard dam located in Eagle, CO. This high-altitude project, located at over 8,500’, included challenging work conditions due to a remote project site as well as working in an environmentally sensitive area. ESCO completed all zoned embankment, reservoir water control, a Roller-Compacted Concrete overtopping, and various outlet structures and drains in an extremely constrained site so as not to impact the mountain environment. This work also included the installation of a pedestrian bridge, instrumentation including telemetry and SCADA systems, and sand filter layers and gravel drains. ESCO self-performed the construction of Sylvan Lake Spillway so as to stay on-schedule and while collaborating with the various project stakeholders and the general public.