Event: Climatic factors/sea-level rise, 2021

The Port of Seattle has regularly been disrupted by flooding and erosion, which has resulted in a shrinking shoreline in recent years. Significant disruption at the port and its hinterland access occurred during the most recent flooding event, which followed a new daily rainfall record was set in October 2021.

Causes and impact

Weather disruptions, including severe flooding, were the main factor for the disruption (Skagit Climate Science Consortium, 2015). Other amplifying factors included: (i) the COVID-19 pandemic and its ripple effects on container shortages and the availability of the port’s workforce and truck drivers; (ii) topography, with the port area bounded by the Pacific Ocean and Puget Sound in the west and the Cascade Mountains which form a barrier to the east. The port is crammed within a narrow corridor with very limited north-south road and rail connectivity; and (iii) surge buying and bullwhip effects along the supply chain, immediately before the weather events.

The impact on the ecosystem around the Port of Seattle was severe, and affected low coastal lands, farmland, coastal septic systems, and hinterland infrastructure. The impact on sea biodiversity was also important. Vessels waiting at anchorage raised safety concerns when high wind speeds threatened to unmoor them.

Response and mitigation measures

The Port of Seattle, in close collaboration with the neighbouring residential communities, took a set of emergency measures, namely: (i) use of digital tools shared across port stakeholders; (ii) implementation of weather forecast and risk assessment procedures to detect potential population clusters with no access to food sources and other priority threats across the port surroundings; and (iii) adapt Puget Sound as a highway for the transportation of primary goods, equipment and people during and after the disruption.

Lessons learned and good practice

  • Implement preventive risk assessment processes and organize coordinated trials and rehearsals with key port and community stakeholders prior to the event. This has proven useful and enabled the Port of Seattle, for example, to deploy emergency plans during the 2021 flood-led congestion (Holdeman E., 2021).
  • Take proactive and creative actions that leverage local accessibility and mobility options during a disruption. For example, the Puget Sound waterway was adapted as a highway to transport supplies, equipment and people during and after the disruption.
  • Implement digital solutions that enable continuous risk assessment before and during a disruption. For example, these have helped the Port of Seattle to continuously adapt its strategy and operational plans.
  • Ensure infrastructure improvements dedicated to minimizing damages from disruption including flooding. These may include wharves improvements, the relocation of buildings, rail yard expansion, apron upgrades, and slope stabilization measures.