For a place known as “the garden city,” a nearly six-story-tall fabric flower makes an apt icon.

By Jan Brenny

Although only one calla lilly is “in bloom” on the beach in Vina del Mar, Chile, with a flower this size, one is all you really need.

For Colombian fabricator Castro Rojas Ingenieros y Arquitectos Ltda., helping engineer and build the steel and fabric city symbol was a new experience. “This was a very unusual project for us,” says general manager Gerardo Castro, who co-owns the business with his sister, Esther, an architect. “Usually our structures cover some space, but in this case, we were creating an icon, and that was unique for us.”

The behemoth bloom was part of a renovation project around Caleta Abarca Beach. Vina del Mar Mayor Virginia Reginato and her team came up with the idea of creating the city landmark as part of the area’s overhaul. The idea was to “showcase a new iconic place for the city,” explains Jorge Heen, architect in charge of the main project. The sculpture sits adjacent to the main coast highway, marking where the city’s two main roads converge. The creation has become a reference point for the city, Heen says.

Vina del Mar, Chile, also known locally as La Ciudad Jardín (Spanish for “The Garden City”), was founded more than 100 years ago as a weekend retreat and garden residence for the well-to-do of Valparaiso and Santiago. Today, approximately 300,000 residents live in the coastal town, which is filled with manicured lawns, parks, gardens and other beautiful green spaces. There’s even a “garden clock,” with numbers made up of flowering plants. The town’s colorful beauty, as well as area beaches, draw thousands of vacationers every year.

Project pairing

When planning the project, city officials first contacted Desmontables S.A., a Chilean engineering and architectural firm—“our partners in Chile,” Castro explains. Owner Osvaldo Sotomayor then contacted Castro. The two companies had collaborated on projects in the past. “Desmontables is the most experienced Chilean company working on fabric structures,” Castro explains. “We had already carried out several projects in that country.”

Each firm employs about 25 people, including architects, engineers, technicians, shop workers and installation experts. Castro Rojas handled the fabrication and engineering, while Desmontables handled the architecture and steel design for what was dubbed the “Cala Project.” (Cala is the Spanish word for “lilly.”) Both firms helped install the sculpture.

Fine-tuning the flower

City officials had come up with a preliminary design for the sculpture, but reality dictated some necessary changes—especially when building began. “The main problem during construction was the site,” Castro says. ““On the beach, high winds blow every day. And we could only access the site with a crane from a nearby street.”

To withstand the wind, the sculpture’s concrete support column, as well as its surrounding steel framework, had to be re-engineered. Designers added steel posts and cables to stiffen the eight-inch-diameter steel tube ring forming the rim of the flower. Steel rings and cables added to the lower part of the structure helped reinforce and stabilize it. Nonetheless, the calla lilly’s warped shape complicated fabrication and assembly, Castro says.

“The main design challenge was to deal with an extremely complex geometry,“ he notes. “The architectural design of the steel structure had to be mathematically reconfigured to make it buildable.”

The project took nearly two months to design, and another two months for fabrication and anchor plate installation. Workers from the two companies spent the final three weeks assembling the steel framework and installing the fabric.

Fabric architecture

Castro spent 11 years in New York City working for Weidlinger Associates, where he helped design the Georgia Dome. Today, his projects typically “cover some space”—for instance, a roof over a soccer stadium grandstand. The Cala Project, because of its height, its asymmetrical shape and its location, was more high-tech, requiring higher levels of engineering analysis and design, which he enjoys.

Those types of projects “force us to be more creative and to create some fabric architecture,” he explains. Many didn’t believe the lilly was made of fabric. “The surface is well-tensioned and wrinkle-free, so people thought it was something else, like a metal sheet, but the truth is that it would have been very difficult to do with something other than fabric.”

Jan Brenny is a Minneapolis-based writer and editor.