Upgrading SEA

How Seattle-Tacoma International Airport is delivering progress while preserving the passenger experience

By Mandy Xiggores, Assistant Director of Aviation Capital Programs, Port of Seattle

Seattle-Tacoma International Airport (SEA) is undergoing a significant transformation that reflects both the scale of its operations and its vision for the future. Record passenger volumes, population increases across the Puget Sound region and the 2026 FIFA World Cup games are driving a $4.6 billion, five-year modernization program known as Upgrade SEA.

Launched in 2023, Upgrade SEA comprises more than 120 projects spanning terminal interiors, security checkpoints, circulation patterns, baggage systems, roadways and digital tools, all focused on delivering a frictionless passenger experience now while supporting the region’s long-term growth and demand for air travel tomorrow.

All of this work is occurring while SEA Airport has served more than 50 million passengers annually for the past three years in a highly constrained 2,500‑acre footprint. To deliver Upgrade SEA successfully in this environment, the Port of Seattle adopted two parallel priorities: preserve the existing passenger experience during construction while delivering a more efficient, modern passenger experience for the future.

Integrating the delivery structure

Maintaining a fully operational airport while delivering a complex, multi-year construction program requires disciplined coordination. For Upgrade SEA, we have developed a successful model for delivering large-scale airport modernizations.

The Upgrade SEA program delivery structure consists of three integrated groups, each with distinct functions but a shared goal to ensure a positive passenger experience now and in the future:

1. Aviation Capital Programs (AVCP). Serving a hybrid planning‑to‑delivery role, the Aviation Capital Program group incorporates the passenger experience from the earliest stages of project development. Our objective is to deliver vetted scopes of up to 15% design completion, schedules and budgets as projects advance to design and construction. The AVCP’s approach equips the managers responsible for delivering those projects with a solid vision for and understanding of the intended passenger experience.
2. Aviation Project Management Group (AVPMG). When a project is ready to advance to design and construction, the Aviation Project Management Group takes the lead. The AVPMG executes and coordinates concurrent projects across the campus. They manage sequencing, phasing and interim conditions to minimize impacts on the operating airport, working closely with engineers, construction managers and regulatory partners to maintain passenger access, safety and service continuity while advancing the overall capital program.
3. Operational Readiness, Activation and Transition (ORAT). As construction projects near completion, ORAT mobilizes to prepare facilities, systems and stakeholders for opening day. Collaborating with tenants and operators, ORAT confirms procedures, trains staff on new equipment, conducts operational trials and addresses risks, ensuring new spaces function as intended and enhance the passenger experience the moment they open.

The Port’s integrated delivery structure enables us to deliver an elevated passenger experience while maintaining the integrity of the existing journey.

Reinforcing a passenger-first approach

While the Port’s integrated delivery structure provides the foundation for how Upgrade SEA is planned, delivered and activated, it is not the only factor driving our success. The Port has paired this structure with complementary strategies that reinforce passenger‑centric decision‑making, reduce risk and support continuity in a live airport environment. Together, the following practices help translate organizational alignment into consistent, on‑the‑ground results for travelers.

• Multidisciplinary planning team. Early in project development, the Port assembles a team representing a cross-section of the organization, including airport operations, customer service, accessibility, the Aviation Project Management Group, Operational Readiness, Activation and Transition and SEA Airport’s in-house art curator. Bringing these perspectives together early introduces operational insight, customer feedback and emerging technology considerations into project scope, phasing and design, helping identify and mitigate risks while keeping projects passenger-focused.
• Early, continual stakeholder engagement. Airport Capital Programs engages with the Aviation Project Management Group and stakeholders in early workshops and design charrettes to align around shared goals and constructible solutions. The Port works closely with airlines, tenants and operational partners to carefully sequence construction, preserve critical circulation paths and shift the most disruptive work to overnight windows whenever possible. Ongoing Upgrade SEA outreach keeps these stakeholders informed about upcoming work, while regular coordination forums, such as monthly airline meetings, provide opportunities for Port staff to answer questions and address concerns.
• Modeling and visualization. As the project progresses, we use advanced modeling and visualization technologies to understand better how construction activities and completed projects affect passenger flow. These capabilities allow Port leadership to compare scenarios, perform model coordination and clash detection and make more informed decisions that improve wayfinding, circulation and the overall passenger experience.

Beyond informing internal audiences, modeling and visualization tools, such as virtual reality, help us communicate Upgrade SEA externally. VR allows the public to see what is behind the construction barricades, serving as both a public information resource and another way to maintain engagement during construction.

• Real-time passenger feedback loops. Throughout construction, SEA Airport’s in-house Business Intelligence team actively monitors the passenger experience. Since April 2023, monthly traveler surveys have measured how often passengers encounter construction, perceived impacts and awareness of the Upgrade SEA program. This real-time feedback enables projects and operations teams to adjust phasing, communications and mitigation strategies to minimize disruption.

• Centralized construction reviews. Coordination across Upgrade SEA is reinforced through a centralized construction advisory review process that identifies and resolves potential impacts before work begins.

Each activity is reviewed holistically, with input from the Operational Readiness, Activation and Transition team and key operational stakeholders, to assess effects on passenger flow, safety, wayfinding, access and airport operations. This proactive review allows teams to adjust sequencing, refine phasing and implement mitigation measures and coordinate communications to ensure construction activities align with the airport’s commitment to a predictable, high‑quality passenger experience.

• Clear wayfinding and visual cues. During construction, SEA Airport relies on a layered wayfinding strategy to help passengers navigate changing conditions with confidence. Temporary signage, floor markings, overhead banners, and visual landmarks clearly communicate detours, alternate paths and key decision points.

These visual cues are reinforced by the Port’s Pathfinder customer service team and SEA Airport’s volunteer ambassadors, who provide real‑time, on‑the‑ground assistance in high‑traffic areas, proactively guiding travelers through evolving layouts.

Ultimately, these strategies help ensure that every phase of construction supports a predictable, intuitive and passenger‑focused experience.

Delivering progress without compromising the journey

Upgrade SEA reflects a deliberate balance between meeting today’s needs and preparing for tomorrow’s demand. By preserving the passenger experience during construction, SEA Airport continues to operate reliably amid unprecedented growth. At the same time, the program is delivering long‑term improvements that simplify the journey, reduce friction and create a more intuitive, resilient airport for the future.