HDOT Climate Resilience Action Plan | May 2021

A Message from Ed Sniffen, Deputy Director of the Highways Division

Aloha, Hawai‘i is resilient and self-sufficient. From its very first inhabitants, decisions and actions have been made to accommodate, adapt, and thrive with nature. For thousands of years, environmental conditions in Hawai‘i and worldwide have been relatively stable. But such conditions are now changing. Global average temperatures are increasing; sea levels are rising; and in many parts of the world storms are becoming more frequent and intense. These changing conditions have important implications to Hawai‘i – inundated shorelines, coastal erosion, floods from rainfall, a higher water table, more saturated soils and greater risks of landslides, and increased wildfires. Given our understanding of what is changing, we need to make some tough decisions to ensure the long-term viability of the State. It no longer makes sense to continue the same approaches we have been using to maintain and improve the State Highway Network, which assume historic environmental conditions will remain unchanged. The Highways Division of the Hawai‘i Department of Transportation (HDOT) needs to be more resilient, adaptive, and engaged in climate change risks to our highway network. It is our responsibility. This Action Plan is our first step to act comprehensively across the agency in recognizing and considering more fully these changing climatic conditions. The Plan is based on research and studies conducted by other agencies to establish an understanding of

how changing environmental conditions will likely impact the State’s highway network in the future. It outlines numerous strategies to ensure that today’s decisions reflect future long-term environmental risks so that every decision and action we make is one that achieves greater network resilience. The Action Plan presented in this report identifies the data used by HDOT staff in designing and managing State highways and how this data, combined with the additional climate data shown as required in the plan, can be used to guide future decisions. It focuses on ways to change key procedures and agency capabilities to be better prepared for climate change. The success of the Action Plan requires collaboration with many other agencies and groups that are critical to the State’s economy and community. Hawai‘i’s community fabric is deeply interwoven, and actions taken by HDOT need to be mindful of the critical need for effective transportation options. Such essential collaboration will ensure that future generations will benefit from the actions HDOT takes today. This Action Plan reflects the input of the professionals who work at HDOT, their thoughts on how to best proceed and change the way they do business to better incorporate resilience into everyday practices. We will work diligently with our partners to ensure the long-term viability of Hawai‘i for the generations to come. Thank you for your support. Mahalo, Ed Sniffen

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