Colorado Public Works Journal, Spring-Summer 2023

SPRING-SUMMER 2023┃23 able, and local energy source rather than burning fossil fuels. This reduces air population while decreasing natural-gas dependence and installs an energy recovery system that isn’t subject to the price fluctuations of the global economy. There is also significant improvement at the sight line. “The wet well is fed by a 72-inch sewer main that ran along the bank of the South Platte, adjacent to the site. It was almost seven feet tall,” Karlos shares. “That huge pipe, which was an eyesore and probably didn’t smell good, was taken below grade. This allowed an entire segment of the riverfront landscape to be returned to the community. Just as important, when we consider the partnership between the City and County of Denver and Metro Water Recovery this project becomes a precedent for inter-organizational cooperation on a legal level as well.” Indeed, cooperation seems to be a must for most infrastructure improvements. In 2015, the National Western Center Master Plan established ambitious sustainability objectives for the forthcoming campus rejuvenation. Among them, the desire to restore the site propelled the City and County of Denver to approach upstream water and sanitation provider Metro Water Recovery about the possibility of relocating the pipeline below grade. At the time, Metro Water Recovery was working on regulating the temperature of clean wastewater (effluent) that they were returning to the South Platte, post-treatment. Their investigation was focused on drawing thermal energy from the pipeline as a means of cooling the effluent, which is better for the flora, fauna, and wildlife within the river’s ecosystem. In adding the possibility of using the extracted thermal energy to heat and cool a campus of buildings, the wheels were set in motion for what is sure to become a benchmark in wastewater rights. “What is interesting about the relationship between Denver and Metro Water Recovery is that they established legal agreements that guarantee future flow rates so there is always an energy source for the campus and also assure that the biosolids, which become a commodity are rightfully returned to Metro Water Recovery,” says Karlos. The complexities don’t end there. The project was delivered under a multi-layered financing process known as a Design Finance Build Operate Maintain (DFBOM) whereby EAS Energy Partners built and now operate the system through an agreement with the National Western Center. EAS is comprised of CenTrio Energy, the largest core-competency district energy operator in North America, AECOM Technical Services Inc., and Saunders Construction. Partners in the district energy system and its future users include the City and County of Denver, CSU Spur, and the National Western Stock Show. And behind it all — Metro Water Recovery is providing thermal energy at no cost. While the idea of free energy certainly ought to sound appealing to entities that own and operate a campus full of facilities, Karlos reminds us that though the CUP is small what’s inside is something more than intricate. For Karlos, like many project managers, the fun is in putting together the puzzle.