The San Ysidro Port of Entry, located in southern San Diego County, is the busiest land border crossing in North America. Every day, around 70,000 vehicles cross to and from the U.S.-Mexico border, contributing to some of California’s poorest air quality and higher rates of asthma among residents. Access to fresh, local food is also limited, and climate-related risks like extreme heat and drought compound existing challenges.  

Many residents access vital resources and build collective power through the non-profit Casa Familiar, which for more than five decades has offered bilingual programs focused on affordable housing, economic opportunities and community development. 

Over time, the organization’s work revealed deep connections between environmental conditions and health outcomes in San Ysidro, particularly related to air quality, limited green space and access to healthy food. As a part of the solution, the organization envisioned a multi-functional space that could serve as a gathering place, an educational resource and a model for climate resiliency. 

From there, the concept of La Semilla — Spanish for “the seed,” symbolizing the environmental justice efforts that can grow from the project — was born. 

“We wanted to create a tangible space, an example of how you can build healthier, climate-resilient places at a neighborhood scale,” says Lisa Cuestas, CEO of Casa Familiar. “It’s about creating something the community can experience, learn from and ultimately replicate in their own lives." Designed and built in close partnership with local stakeholders, the project demonstrates how intentional construction can support health, opportunity and long-term durability in underserved communities.

La Semilla is a case study in collaboration, bringing together Casa Familiar, the design team from Magic Animals and McCullough Landscape Architecture, PCL Construction’s San Diego team, and, most importantly, the residents of San Ysidro themselves. Together, the team set out to create a place that reflects community priorities while modeling what equitable, climate-conscious development can look like at a neighborhood scale.

Set to be completed in the summer of 2026, La Semilla is a mass timber project (an engineered wood construction method that uses large, layered timber panels to replace steel and concrete) that spans an approximately 7,000-square-foot site and consists of two detached buildings: a community-focused facility and a single-family residential unit. The community facility is designed as a year-round gathering space and education center focused on climate resiliency and environmental justice. 

The project is part of a broader shift taking shape across the region, as San Diego leads California’s adoption of mass timber construction, driven by updated building codes, research partnerships and a growing emphasis on lower-carbon building materials. From high-rise wood structures to commercial and residential developments, the region has become a real-time exploration of mass timber’s structural performance and climate benefits, positioning projects like La Semilla within a rapidly evolving and forward-looking construction landscape.

During extreme heat, power outages or other climate-related events, La Semilla can serve as a hub for cooling, charging devices and accessing resources. It will host workshops, educational programming and informal gatherings on a daily basis. 

“Our goal was to create a space that is not something fenced off or exclusive, but a place people pass through, stop at, learn from and enjoy,” says Cuestas. “Even if someone just cuts through the property on their way home and their day feels a little nicer, that’s a success.” 

The design teams from Magic Animals and McCullough Landscape Architecture set out to create a space that was accessible and deeply connected to its surroundings, and went directly to residents to ensure it was.

“The overarching goal was to demonstrate climate resilience by using recognizable construction methods and materials, meaning things the neighborhood could understand and potentially use themselves,” says Brandon Blakeman, founding principal at Magic Animals.

This included incorporating a “food forest” where edible plants mimic a natural ecosystem, installing solar panels and cisterns for water capture and storage, and integrating local artwork into highly visible exterior spaces, all features designed to be approachable and replicable in residents’ own homes.

That idea of relatability — designing with, not for — informed every design decision. The team worked closely with residents through workshops and conversations, asking basic but critical questions: What is missing in the neighborhood? What would make daily life better? What would make you feel welcome in this space? 

“We wanted a place that felt like it belonged to the neighborhood,” Blakeman says. “Somewhere people could come to learn, relax, celebrate and connect.”

Landscape designer Ben Arcia of McCullough notes that the project had to confront environmental challenges — such as air pollution and limited green space — within an unusually small footprint.

“We didn’t have the scale to solve everything, but we could lead by example,” Arcia says. “The idea was crowdsourced, community-based resilience and showing the possibilities in a way that’s relatable and repeatable.”

That philosophy is reflected in La Semilla’s features: in addition to the food forest, there are shaded gathering areas, solar power with battery storage and electric vehicle charging. Each element serves a purpose while also acting as a teaching tool by demonstrating what sustainability can look like in a neighborhood context. 

Turning that vision into a buildable, functional reality required an equally intentional approach to construction. For PCL, La Semilla is not a typical community project. It is a compact, multi-use resilience prototype built within a tight residential footprint, where every design ambition must be translated into something constructible, durable and accessible to the community it serves.

The La Semilla project integrates a community-focused facility, a residential unit and outdoor environmental learning spaces into a highly constrained footprint. Each component carries different requirements, yet all must function together as a cohesive, accessible environment that remains open and welcoming to the neighborhood.

“We’re literally building in the heart of the community,” says Brian Chen, a PCL project manager. “People walk by every day, ask questions, watch what's happening. It really reinforces that what we're building is for them."

That visibility shaped how the team approached construction from day one. With limited space for staging and an active residential setting, traditional construction approaches had to be adapted. The team carefully phased the work, coordinated deliveries to minimize disruption and aligned daily construction activities with how the surrounding community uses the site. 

The project also required thoughtful integration of mass timber and other sustainable systems, approaches that support the project’s environmental goals while introducing a higher level of precision and coordination not typically found in projects of this scale. In this way, the building process becomes part of the project’s broader purpose: demonstrating what climate-resilient, community-centered development can look like in practice.

“We’re building something that’s going to last far beyond us and have a much bigger reach than the time we spend here,” says Chen. “A project like this reminds you that construction can have a real, personal impact on people’s lives.”

For Lucas Mallory, PCL’s San Diego area manager, that’s what makes projects like La Semilla meaningful.

“These are the projects that give meaning to what we do,” says Mallory. “It’s not just about delivering a building; it’s about supporting a vision that serves the community and elevates what’s possible.”

La Semilla illustrates what can happen when construction, design and community advocacy align around a shared purpose. Each partner brought expertise, but the project’s strength lies in how those roles overlapped, supported by a delivery approach that prioritized early coordination, shared problem-solving and adaptability as community input shaped the project.

For the design team, the goal was to create spaces that foster connection and inspiration. For PCL, La Semilla reinforces the idea that construction can be a catalyst for positive change when it’s rooted in community values. The project reflects the approach PCL brings to all of its work: thoughtful construction leadership rooted in adaptability and collaboration and built to support community-led infrastructure.

And for Casa Familiar and the San Ysidro community, La Semilla is a physical expression of decades of advocacy — acknowledging challenges without being defined by them, and investing in people as much as infrastructure.

Intentional design and construction, as La Semilla shows, is about more than what gets built. It’s about who it’s built for and the opportunities it creates long after the last crew leaves the site.