From the outset, the design team faced several complex challenges typical of dense, high-traffic urban sites:

• limited soil volume
• extreme surface loads
• stormwater control
• root management

Ensuring long-term tree health in this environment demanded a rethink of traditional planting methods. Small tree pits or planter boxes would have confined root systems and stunted canopy growth, falling short of the project’s vision for a thriving, shaded public plaza.

The stadium’s expansive paved plazas also introduced structural pressures. The landscape had to support maintenance vehicles and crowds of thousands while still providing a continuous underground soil zone where trees could grow unimpeded. Any solution needed to balance load-bearing strength with soil porosity— a task beyond conventional techniques.

Stormwater management was another critical objective. With more than an acre of hardscape, heavy Ohio rains could create significant runoff. Rather than directing this water into municipal drains, the design aimed to capture, filter, and reuse it on-site to nourish the trees and relieve the stormwater system.

Root management presented the final piece of the puzzle. The team needed a way to guide roots to develop strong, deep structures that would also protect pavements and utilities as the trees matured. These intersecting challenges - soil, structure, water, and root control - called for an integrated green infrastructure system.

To address these complex challenges, the design team partnered with Citygreen to implement a series of integrated green infrastructure solutions that would make the stadium’s landscape both resilient and visually seamless.

The design team conceived a hidden, load-bearing forest floor under the stadium. At the heart of the solution was

the Stratavault™ soil cell system to unlock generous root zones beneath the stadium’s paved concourses. Beneath the plazas, an interconnected grid of Stratavault modules were installed to form large, uncompacted soil chambers capable of supporting healthy tree growth, while simultaneously carrying the heavy surface loads of crowds and maintenance vehicles above.

The Stratavault structure preserves around 95% of the soil’s natural volume and porosity, allowing tree roots to expand freely while the system’s lattice of interlocking cells distributes loads evenly. This combination of strength and permeability ensures that trees can thrive long-term without compromising the integrity of the hardscape.

The Stratavault system also doubled as a stormwater management network. Rainfall that lands on the plaza and surrounding walkways filters through permeable paving and inlets into the Stratavault matrix below. There, the soil acts as a natural sponge absorbing, filtering, and holding water for gradual release. This process nourishes the trees passively while easing the strain on city drains during

Ohio’s intense storms. Instead of treating stormwater as runoff to be removed, the landscape now captures and reuses it as a resource, embodying low-impact development principles in action.

Vertical root directors and barriers guide root systems downward, encouraging deep anchorage and preventing surface upheaval and pipe intrusion. By establishing controlled root growth from the start, the design effectively eliminates one of the most common maintenance issues in urban landscapes, while enhancing the trees’ long-term stability and resilience against wind and weather.

Completed in mid-2021, the Columbus Crew Stadium now stands not only as a premier soccer stadium but also as a showcase of green infrastructure in action.

On opening day, fans arriving at the stadium were greeted by the shade of young trees and the aesthetic of a well- integrated landscape that felt like a natural extension of the neighbouring park and riverfront.

Approximately 40 new trees were planted around the stadium concourses and entry plazas, each one positioned in its Stratavault habitat. In the two growing seasons since, those trees have already begun to flourish – a testament to their favourable underground environment.

The uncompacted soil and passive irrigation from stored rainwater have given the trees a strong start, even through the hot Ohio summers. This suggests a promising trajectory: these trees are expected to form a mature canopy in five years, providing extensive shade and cooling to what was once an entirely paved site. The benefits will be tangible to visitors who linger in the plazas on sunny days, enjoying cooler temperatures and the ambiance of greenery in what could have been a heat-trapping concrete expanse.

The stormwater strategy has already proven its worth as well. During heavy rains, instead of water sheeting off the plaza and overwhelming drains, much of it percolates down through permeable joints and inlets into the soil vaults below. Observations after recent thunderstorms showed little to no surface flooding around the stadium – the engineered soil system absorbed and slowed the runoff. This not only protects the venue from puddles and slick surfaces, but it also contributes to Columbus’s broader efforts to reduce storm sewer overflows. Essentially, the stadium’s landscape is performing like a giant rain garden, treating and using rain where it falls

Perhaps the most compelling outcome of the Columbus Crew Stadium project is the way it marries civic space with ecological function. The design overcame the old dichotomy of “either a functional stadium or a green park” by proving it could be both. The stadium plazas are not just pathways to the entrances; they are vibrant public spaces where community members can gather under the dappled shade of trees even on non-game days.

As other cities look to rejuvenate their public venues and infrastructure, the Columbus Crew Stadium case stands as an inspiration. It shows how investing in quality soil systems, smart tree pit design, and root management can pay dividends in beauty, resilience, and performance.