When Boston-area landscape architect Kimberly Garza heard her hometown, Sacramento, had launched an international competition to redesign the lackluster Capitol Mall streetscape, she told a colleague: "We have to do this! I know what the city needs and what it's lacking in terms of public spaces."

That local knowledge proved pivotal.

Garza and colleague Andrew ten Brink of New York were named winners Wednesday of the contest's $20,000 first prize for their re-imagining of the mall's sidewalks and medians as an urban forest, populated by native oaks and pine trees, and studded with event sites, including an amphitheater and farmers market.

Garza said the concept, called "Sacramento's Capitol Canopy," recognizes the ecological and human health benefits of bolstering the city's green canopy.

"The urban forest in Sacramento is in decline," Garza said. "That means increased heat island effect, and increased pollution. There needs to be a strategy in place that responds to that."

Garza, a graduate of the Natomas Charter School Performing and Fine Arts Academy, as well as UC Berkeley and Harvard University, teamed with ten Brink to beat 39 other contestants, including several from outside the United States, officials said.

The competition was co-sponsored by the city of Sacramento and the local architect group AIA Central Valley. Jury member Bill Crouch, the city's urban design manager, called the Garza and ten Brink entry "a lovely design" that made sense downtown.

"We felt it was believable and doable," he said. "It resonated as a design that understood its context."

The design maintains open site lines between the Capitol building and Tower Bridge. The mall's center medians remain in place, but are turned into spaces where people can shop and frolic, including a marketplace and children's water play zone. To add more event room, the street is narrowed in some places to one lane in each direction.

The design also turns Crocker Park into a sculpture garden and adds an amphitheater on the south side of Capitol Mall near the freeway. It includes a pedestrian bridge over the freeway, and creates a riparian canopy along the Sacramento River.

City officials said they and local architects devised the competition to solicit ideas on how to brighten the mall's bland streetscape and entice more people onto the blocks weekdays and weekends.

City development officials said they expect to review all entries, not just the winners, for ideas on how to transform the mall. Any changes to Capitol Mall's street and sidewalks are likely to happen slowly over time, as money becomes available, and as other priority downtown projects advance, city officials said.

Crouch said officials may put together a steering committee to review the ideas and talk about next steps.

"We are looking to do something that is affordable," he said. "There is no money earmarked for this project at the moment. But if you have a compelling vision, money sometimes follows the vision."

Winning entries are online: http://www.dreyfussblackford.com/graphics/winners.pdf

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