The most surprising thing about Rhys Duggan’s grand plan is that nothing’s stopping it.

Duggan wants to build a small city in the middle of Denver. He sees tall, spindly towers rising from the banks of the South Platte River. He sees grocery stores and schools, glass and steel. He sees 17,000 more people — a huge figure for a city that has grown by 100,000 since 2011.

Remarkably, in a city wracked by arguments about development, gentrification and density, the enormous redevelopment project faces little if any resistance. With a series of city approvals last year, the River Mile project is approaching the start of what could be decades of construction.

“To me, that’s part of growing up as a city,” he said in a Denver Post interview.

“I think there’s a growing awareness of the challenges that population growth brings, and perhaps a growing awareness that the model of growth that Denver has adopted previously — i.e., more of a horizontal-sprawl model — is perhaps not sustainable. And it’s taken a couple cycles of growth to really start to realize that.”

Duggan leads the plan for a “River Mile” district that eventually would replace the Elitch Gardens amusement park and surrounding parking lots, a site just west of downtown on a light-rail line. It would take billions of dollars and decades to finish.

“I think that if you talk about potential transformation projects, River Mile, Union Station and National Western Center are probably all three in the same category,” said Brad Buchanan, the city’s former planning director and the current CEO of the National Western Center Authority.

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So far, there’s every sign that it will happen. The Denver City Council last year approved high-level plans and legal changes for the project, including a rezoning that gives Duggan permission to build up to 59 stories high on the site.

Perhaps most important, the project has committed and wealthy supporters: Stan Kroenke, the billionaire owner of the neighboring Pepsi Center and several professional sports franchises, and his family. It’s “not your typical bank loan, not your typical hedge fund investor,” Duggan said.

Still, there’s no firm timeline for “vertical” construction of buildings yet. The project is likely to solve its major planning challenges, Buchanan said — but he and Duggan both say market conditions will determine everything.

“I’m a Canadian, so I’m conservative in my DNA,” Duggan said. “I’m cautious right now.”

How it would happen

Through 2020, Duggan’s Revesco Properties will work with the city on a detailed plan for sewer, water, roads and other infrastructure. Infrastructure costs could be about $600 million, to be funded by a taxing district on the property.

Over the next few years, Revesco will work with governments to re-dredge and rebuild parts of the river. That will protect River Mile and other riverside properties from flooding, and it’s part of a broader effort.

Revesco will build a parking structure to replace the current surface parking lots near the amusement park. Then, the developer can start building on the 17 acres of parking lots. That area could fit up to six towers, a mix of office and residential, without affecting the amusement park.

Eventually, blocks of urban development could replace Elitch Gardens. Revesco already owns the park, but there are no immediate plans for demolition. It will likely stay open for years to come.

The project could include about 8,000 residential units, but city planners say they’re trying to encourage taller, skinnier towers that would keep the area feeling open.

The developer has agreed to set aside 15 percent of the new housing as “affordable” units at a mix of income levels, starting as low as 30 percent of the area median income, or $24,300 for a family of three.

Plans also describe trails and open space along the river, along with a pedestrian plaza near the Pepsi Center transit stop. Duggan will have to keep 15 percent of the site as public parks and open space, including for a potential recreation center, according to an agreement with the city.

The rules for the property include maximum limits on automobile parking, which is meant to reduce auto traffic, while also requiring bicycle parking.

An idea from Vancouver

Duggan keeps a relatively low public profile — he declined to be photographed for this story, for example — but he’s a frequent sight around the city buildings of Civic Center.

Wearing wood-framed glasses and a black V-neck sweater over a white button-up at a recent interview, he looks like a stylish university professor, and he’s known to ride his electric scooter to meetings.

The idea for River Mile, he said, has percolated for decades.

“It struck me 20 years ago, when I moved here in 1998,” said Duggan, who previously lived in Vancouver, British Columbia. “I knew one person — the guy I was working for. I was driving around a lot, and I saw this piece of land which had an amusement park.”

Elitch’s had only moved to the site in 1995. But even then, Duggan saw an opportunity: The property was similar to Vancouver’s Expo 86 land, a former world’s fair site that has become an urban development.

“The site that hosted it in Vancouver had a lot of similarities to this site in Elitch’s. It was downtown-adjacent; it was right next to a sports stadium; it was on the water. It was environmentally challenged, should we say,” he recalled. “I looked at Elitch’s and said, ‘That could be the next Expo lands.’ ”

And then he ignored it, taking on a series of much smaller projects. Revesco describes itself as a “boutique” company, and its portfolio includes single buildings as small as the Arvada Tavern, a retrofitted restaurant in Olde Town Arvada.

Eventually, though, a young new employee of Duggan’s took interest in Elitch’s and tracked down its then-owners. Working with Kroenke, Revesco bought the Elitch’s site for $140 million in 2015, according to property records.

Density debate

Today, the River Mile plan has a unique place in Denver’s citywide growth debates.

It’s one of the major transit-oriented “infill” projects — like I-25 and Broadway, and “Fox Island.” Ironically, these mega-projects have faced less political resistance than much smaller projects in residential areas, where neighbors often complain about traffic and mountain views.

Duggan sees it as evidence that people are willing to accept more growth in Denver — but, for better or worse, not in their backyards.

“I think the reason why the River Mile was well accepted is because I think people saw it as a viable alternative to what some people see — not myself — as unfettered, uncontrolled growth happening within … neighborhoods.”

Councilwoman At-large Debbie Ortega voted for the project’s rezoning, but she is concerned about all the intensity of development along Interstate 25, from the displacement of renters in northwest Denver neighborhoods to roads and sewers. The city has plans for the area, but she’s not convinced they’re as detailed as earlier efforts near Union Station.

“We should be looking at how do we maximize efficiencies around the infrastructure improvements that are going to be needed,” she said. “I want to make sure someone’s looking at the bigger picture.”

Duggan, meanwhile, thinks the city’s next phase of growth will depend on transit, walking and other options.

“More and more residents are realizing that we’ve tried to accommodate growth a certain way — sprawl, highways, single-occupancy-vehicle cars — and maybe the results aren’t what we wanted them to be. We can do something better,” he said.