A visit to the old town neighborhood of San Diego will take you back in time to the 1800s when the West was wild and California was a new state in the union. Old Town is considered California’s birthplace because Spanish priest Junípero Serra founded the state’s first mission in the area. Today, nine city blocks make up Old Town State Park, which features original adobe buildings, California’s first schoolhouse, a blacksmith shop, stable and the state’s earliest newspaper office. The area offers tourists a history lesson while they shop for traditional Mexican wares and enjoy authentic local cuisine. North of Old Town’s eclectic buildings and Southwestern-style courtyards, 15 acres (6 hectares) of land belonging to the state of California had been a visual distraction to local residents. The site hosted facilities for District 11 of the state’s transportation operations, Caltrans, including temporary trailers, warehouses and a fuel island and storage tank to maintain its fleet of vehicles. The 1950s facilities were no longer up to California’s seismic-code requirements; in 2000, the state’s Department of General Services decided to build a new office structure on the site, consolidating nearly 1,000 Caltrans District 11 employees who had been interspersed around the county.

Architecture firm, Carrier Johnson, San Diego, led the design for the design-bid-build project. Although the state of California was not funding green buildings when design for the building began in 2000, Michael Johnson, Carrier Johnson’s design principal, says sustainability is part of the 30-year-old firm’s culture and guides many design decisions. The success of the 301,000-square-foot (27963-m2) Caltrans District 11 headquarters complex, which includes three office buildings, a central-plant building and a fleet maintenance facility, began an initiative to green all state office buildings. GUIDING SITE Although the original program called for one building to house District 11’s employees, Ed Holakiewicz, senior designer on the project, considered the context in his design. “Our two significant neighbors are the Old Town historic community that’s primarily made of 1- to 2-story adobe buildings on one side and a 70-foot- [21-m-] high freeway interchange and Amtrak line on the other side. It was important to deal with those diverse neighbors and create a project that harmonizes with both.”

Holakiewicz also took into account that the site once was a riverbed; extra care would need to be taken to ensure anything constructed on the site would minimize impact on very soft soil. In addition, a seismic fault crosses the east corner of the site, parallel to the railroad line, and had to be avoided. “The site’s neighbors and natural conditions were the most significant challenges of the project but perhaps the greatest catalyst for the design because it was the response to these things that created the design,” Holakiewicz says. Instead of one monolithic office structure, his concept was to create multiple buildings at different vertical scales—taller façades up to 5 stories near the highway interchange and stepped-down façades of a minimum 2 stories toward the Old Town neighborhood—connected by bridges and outdoor walkways.

By creating multiple buildings, Holakiewicz could position the structures from urban and sustainable standpoints. Each of the five buildings is set back 70 to 90 feet (21 to 27 m) from the street, creating a landscaping buffer between Caltrans’ buildings and Old Town. “The positioning of the buildings began to take on the shape of the site,” Holakiewicz remarks. “And with the buildings clustered on themselves, they create their own noise and solar protection.”

Facing out to the community, the buildings feature a limestone and precast concrete skin with recessed windows to aesthetically integrate with Old Town’s historic Spanish architecture motif. Facing into campus, curtainwalls allow natural light to penetrate each office building. Holakiewicz ensured that if a building has a west-facing glass wall, there is a building across the way that provides shading.

“That brought light into each building in a protected way and also incorporated social aspects,” Holakiewicz says. “When we talk about sustainable design it’s not just energy; it’s also quality of space for people. One of the items that came up in our dialogue early on with the state and Caltrans was people like to see other people. It creates a very strong social working environment. The extensive glass facing into campus encourages interaction, as do open interior environments.”