C+S June 2021 Vol. 7 Issue 6 (web)

In September 2020, City Park Golf Course began hosting golf rounds again after a significant redesign. A $45 million renovation project successfully integrated stormwater detention and water quality im - provements into the existing 136-acre site to protect nearby neighbor - hoods from flooding. The drainage improvements triggered a complete renovation of Park Hill Golf Course, including a new layout for the 18-hole, par-71 course, a full driving range, and installation of a new clubhouse with community event space. The project began in 2017, as part of the City and County of Denver’s larger Platte to Park Hill stormwater drainage infrastructure program the City was implementing to protect people and property against flooding, while improving water quality and enhancing public space. The City Park Golf Course project was controversial because the needed stormwater detention volume to protect nearby neighborhoods would alter the course routing and require the removal of mature trees. From the beginning, the existing mature trees on the golf course be - came a major project consideration for the team. Martin/Martin, the project Engineer, had to weave 9 holes of golf around a 100-year flood detention facility sized for over 200-acre feet of water. Martin/Martin worked closely with Landscape Architects at Dig Studio, who identi - fied drip line protection zones and limits of disturbance, and provided planting plans for the constructed wetland channel. Another major constraint was the integration of the drainage infrastructure into a play- able golf course layout. The Engineer, Landscape Architect, and Golf Course Architect, Icon Golf, worked hand- in- hand to maximize the stormwater infrastructure and save existing trees, while improving the golf course play experience. The resulting stormwater detention area effectively manages and con- trols the flow of stormwater to downstream neighborhoods within the 9-square mile Montclair basin – one of Denver’s largest drainage ba - sins. The system collects stormwater from the basin upstream and then works to release slower flows into an existing pipe north of the course, helping to prevent flooding in the downstream neighborhoods that had been prevalent for years. The detention basin and open channel design also added to golf playability strategy, aesthetic beauty, and provided an opportunity to clean the water before it goes down stream. City Park Golf Course Opens as a Key Project in Denver’s Platte to Park Hill Stormwater Program A close collaboration between the Civil Engineer, Golf Course Architect, and Landscape Architect results in a redesigned course that meets multiple community objectives By Bill Vitek, FASLA, PLA

Another major benefit for water quality is provided by a trash vault at the entry to the north drainage outlet. The vault captures approxi - mately 6,600 cubic feet of trash annually, preventing debris from being directed into the drainage channel, eliminating a tremendous amount of waste. The team engaged nearby residents and the community at large to convey information about the project, how it would serve the future needs of the broader community, and plans for reforestation of the golf course. Many citizens didn’t realize that two thirds of the existing trees would remain, and that 760 new 2-3” caliper trees would be installed, establishing a “next generation forest” at the golf course. Educational sessions were hosted before removal began, explaining what trees would be removed and why, and what the plans were for reforesta- tion. Ultimately, neighbors realized there was sound methodology and expertise that went into solving the many faceted challenges of the project, and the greater community benefits the project would provide. Dig Studio worked closely with Denver’s City Forester and the project engineer to identify trees to be removed based on health or hazard threats. Other trees needed to be removed or relocated to make way for the drainage improvements and to allow for playability of the rede- signed golf course. Numerous factors were considered in the selection of new tree species at the golf course. Dig Studio tested the evolution of Denver’s traditional horticultural zones to respond to a warming climate, salt tolerance to withstand the grey water from the City’s reclaimed water system, and the ability of species to survive being inundated by stormwater for short periods of time. Due to their inability to withstand salt from recycled gray water, evergreens comprised only 10 percent of the total tree counts. Diverse varieties were sourced from Colorado and around the country, and were held in an on-site tree nursery prior to installation. “From the city’s perspective, we looked at this as an opportunity to create an arboretum at the golf course,” said Mike Swanson, Denver City Forester. The city looked at this as a ‘clean slate’ to plant species they knew had worked successfully in other parks, and to experiment with new species that are tolerant within Denver’s horticultural zone. “We have so few native species, if all these different species survive, the diversity of it all is a big win for the city.”

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June 2021

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