At a location lower in the basin where stormwater concentrates, an East-West corridor extending from 39th Avenue was selected for the greenway. This greenway will both intercept overland flows in larger storms and help naturally clean stormwater in smaller events as it flows and conveys to a river. A key challenge with the project was completing the project in a tight urban corridor with businesses and residents surrounding the two-mile-long project site. Therefore, a robust community outreach process was established, enabling the City to uncover design aspects most important to the community which included gathering and recreational spaces, incorporation of native landscapes and materials, and increased connectivity for pedestrians, drivers, and bikers. The City reconstructed the urban landscape where possible, slowing down and filtering the water through vegetation to remove contami- nants, all while controlling storm runoff and nourishing greenery to help residents endure the climate shift toward droughts and rising temperatures. Greenways help remove waterborne contaminants by exposing them to sunlight and slow and control stormwater across wider channels and gentler banks. To further the treatment process, over 50 street side stormwater quality planters were installed to collect and filter water through various layers of vegetation and soils. Addi- tionally, two new trash vaults add 1,000 cubic feet of trash collection in the basin Precast, reinforced concrete boxes were installed underground on both sides of the greenway, connecting the overall system and allowing for future extension further into the basin. Storm flows will be intercepted and directed from newly constructed boxes on one end through the greenway and back through additional new boxes and pipes leading to the Globeville Landing Outfall – which ultimately empties into the South Platte River. Another key component was careful planning and designing around an existing 100-year-old, 120-inch brick pipe. The existing pipe was inspected and found to be in good condition, allow- ing for reuse. The reuse of this pipe helps convey a significant portion of the stormwater to the South Platte River and reduces the need for another bored tunnel under the Union Pacific Railroad. The new greenway project will replace the City’s aging infrastructure with nearly 12 acres of new recreational open space and increased connectivity. Three vehicular and two pedestrian bridges will connect people across the channel, and the site will feature the first shared street in Denver. The new green infrastructure will better control stormwater, improve water quality and public safety, increase plant diversity, and improve natural ecosystems – all of which were top priorities for the City and community. Once complete, the new space will include more pathways and bridges, 5,000 square feet of community gardens and an outdoor amphitheater. Engineered outfall within Superfund site and railyard Globeville Landing Park is the final stop for stormwater traveling from northeast Denver to the South Platte River. Five hundred linear feet of large diameter pipes were installed to carry stormwater under 17 freight train tracks and two heavy commuter rails, and through an existing Superfund site, before it rises to the surface at a natural open channel with a capacity of 2,300 cubic feet per second.
While the treatment train is essential to the Platte to Park Hill project, the City was challenged with smartly integrating these elements into a beloved City course. Through a collaborative design process, the drainage improvements, including re-grading of 200 acre-feet of de- tention, were integrated in such a way as to become part of the course itself. Playability is now enhanced and challenged by the drainage and stream features. Using green infrastructure in an urbanized area to capture a 100-year storm Even with the City Park Golf Course redesign to integrate these storm- water features, the Montclair Basin still lacked the infrastructure for handling the water produced during a 100-year flood event. Therefore, the City opted to combine a greenway and stormwater pipe system to create the backbone of the needed drainage system. December 2018 aerial view of the City Park Golf Course. Photo: Rocky Mountain Photo
The Platte to Park Hill: Stormwater Systems Project is a coordinated and community-led approach to a series of engineering-focused projects that will address flood protection in northeast Denver neighborhoods. Photo: Design Workshop, Inc.
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january 2020
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