A River Reborn

On a crisp Colorado morning, the South Platte River weaves a reflective path through downtown Denver, serving as both a living memory of the city’s origins and a testament to its ongoing evolution. For decades, this segment of the river was molded for efficiency: confined, straightened, and fortified against floods. However, the narrative is shifting with The River Mile: South Platte River Restoration Project.

Today, the South Platte is at the core of a $120 million public-private restoration initiative in Denver’s urban heart. As part of Denver’s Urban Waterways (WATR) initiative and the U.S. Army Corps of Engineers’ comprehensive seven-reach South Platte River master plan, this restoration aims to foster an ecologically robust floodplain that facilitates future redevelopment of the existing Elitch Gardens site, Ball Arena, and surrounding areas. The developer’s ambitious goal was to remove the sites from the floodplain, not merely by constructing barriers, but by restoring the river itself.

This innovative design marks a milestone as the first riverine project in the Western United States to earn WEDG® (Waterfront Edge Design Guidelines) Verification, underscoring Denver’s commitment to resilience and reconnection.

Engineering, Unconventionally 

Calibre Engineering, a Colorado-based civil engineering firm, directed a multidisciplinary team, which included Wenk Associates, Birch Ecology, Waterways Consulting, S2o Design & Engineering (now part of Calibre), and others, through one of the region’s most ambitious river restorations.

“Most teams start with flood control,” reflects Ben Murphy, Project Manager at Calibre Engineering. “We started with the river itself.”

Historically, the South Platte had evolved into more of a channel than a river, becoming shallow, sediment-laden, and constrained by decades of urban development. Previous design efforts primarily focused on flood conveyance, but the team recognized a greater opportunity: to heal the river while safeguarding the city.

The project site is situated within an extensively developed urban corridor, presenting significant challenges in reintroducing meandering. Recognizing this, Revesco Properties, the property owner at the time, made the unprecedented decision to donate over two acres of land to facilitate the river’s natural bend and flow. This choice, rarely seen in private development, demonstrated a profound understanding of what the river required to thrive.

The developer and design team envisioned a channel that could breathe, bend, and meander within its limits, enhancing habitat, expanding flood capacity, and reconnecting people to the water’s edge. By integrating Low-Impact Development (LID) strategies alongside sophisticated hydrologic and hydraulic modeling, they constructed a system capable of managing floods, improving water quality, and bolstering both ecological and community functions.

The project further addressed more than thirty stormwater outfalls within the river’s reach, which previously discharged untreated runoff directly into the South Platte. Instead of minimizing efforts for cost-effectiveness, the team consolidated and redirected these outfalls through constructed wetlands, transforming them into natural treatment zones that filter urban runoff and safeguard downstream water quality.

Teaming Beyond Convention 

Calibre Engineering brought meticulous precision to the project, while Wenk Landscape Architects infused ecological insight and a human-centered focus. This collaboration blurred conventional boundaries between design and engineering, structure and spirit.

“What made this partnership special was that the engineers weren’t just solving problems, they were co-creating a place,” says Greg Dorolek, Principal of Wenk Associates. “We began the with the ecological goals for the river. We looked at modifying the channel cross-sections that would support more biodiversity and habitat. Then we engineered the hydrology to support these goals.  Calibre encouraged us to think big, then helped us make it real.”

The team reframed the project not merely as an infrastructure endeavor but as a park initiative with infrastructure responsibilities. Their vision fostered a landscape that felt natural and interconnected—a river that could support both ecological systems and everyday human use. This shift influenced every design decision, from grading and vegetation selection to access and long-term maintenance planning.

Designing with Friction 

Collaboration often invites differing opinions. When the design team suggested reinstating native willow stands along the riverbanks, crucial for soil stabilization and stormwater filtration, the city initially resisted. Public Works raised concerns about maintenance and safety, advocating for broad paved access roads along the corridor. Rather than dismissing these concerns outright, the team promoted open dialogue, striving to strike a balance between the city’s operational needs and ecological integrity.

“We wanted to find balance, not opposition,” Murphy explains. “Our goal wasn’t to win an argument; it was to create a river system that worked for everyone.”

By maintaining this balance, the design team encouraged collaboration among departments, fostering a shared vision for a revitalized South Platte River—where nature and urban life can thrive in harmony.

“That was the power of this project,” notes Greg Dorolek, “It brought people together who’d never been in the same room before: engineers, ecologists, city leaders, and community voices, all focused on restoring the river.”

A Model for Collaboration

The success of the South Platte River Restoration Project stems from both its process and product. It required a blend of diplomacy, technical rigor, and a shared vision from all partners involved. The City and County of Denver, Revesco Properties, the Mile High Flood District, the U.S. Army Corps of Engineers, and a multidisciplinary design team collaborated to harmonize regulations, address ecological concerns, and prioritize community needs. This collective effort has created a replicable model for future segments of the South Platte River under the WATR initiative.

What WEDG® Means for Denver

Achieving 151 out of 250 points, the River Mile: South Platte River Restoration Project set a record as the highest WEDG® score in the program’s history. This distinction underscores the team’s commitment to the three pillars of WEDG®: ecology, access, and resilience. For Denver, it represents a transformative approach to waterfront redevelopment, viewing it not only as a means of flood mitigation but also as a catalyst for community revitalization.

“WEDG gave us a language for what we were already doing,” says Murphy. “It’s about more than compliance; it’s about commitment.”

Engineering Possibility

This river restoration project stands as a testament to what can be achieved when developers, designers, and city leaders unite around a common goal. It reflects not only what was built, but how it was built—through listening, curiosity, and a shared belief in the river’s potential.

“We aimed to create a place where people could enjoy a leisurely morning and reconnect with their river,” Murphy explains. This connection between individuals, disciplines, and nature may very well be the project’s most significant legacy.

A Blueprint for the Future

The River Mile: South Platte River Restoration showcases the remarkable outcomes that can occur when technical precision meets creative courage. By asking probing questions and exploring possibilities, the project team did more than restore a river—they redefined the future of engineering in the 21st century.

Because when developers, designers, and communities choose curiosity over convention, they don’t just rebuild rivers. They redefine what’s possible.