Agent of Change

UH Study Reshapes Honolulu’s Urban Core to Embrace Sea Level Rise

Miami. New York. Tokyo. London. While the list brings to mind some of the world’s greatest cities, it also doubles as a list of locations most vulnerable to future sea level rise. Unfortunately, an extension of this list would also include many other well-known cities across the world, including Honolulu, Hawai‘i.

Over the next few decades, Hawai‘i could face a rise in sea level of up to three feet, with some estimates predicting a rise of up to six feet. In Honolulu, it is estimated that the rise in ocean levels resulting from climate change could force over 13,000 people from their homes and result in $13 billion in economic losses.

Professor Judith Stilgenbauer

“When you read all the reports on sea level rise, it’s frightening,” said Judith Stilgenbauer, professor of landscape architecture at the University of Hawai‘i at Mānoa (UH Mānoa). “However, we have a real opportunity here on O‘ahu and in Honolulu to get an early start on planning for the inevitable.”

The opportunity that Stilgenbauer refers to is a comprehensive study released earlier this year by the University of Hawai‘i Community Design Center (UHCDC) that proposes radical changes to Honolulu’s south shore in response to sea level rise. Entitled, South Shore Promenade and Coastal Open Space Network Study: Resilience and Connectivity by Design, the two-year study was the result of an applied research, analysis and proof-of-concept planning and design project funded by the State of Hawai‘i Office of Planning to serve as a visionary tool to stimulate dialogue among federal, state and city leaders on the future planning along the south shore of urban Honolulu, which stretches from Diamond Head to Pearl Harbor, and includes the world-famous Waikiki Beach.

The UHCDC approach utilizes speculative, nature-based living shoreline (soft) design solutions to embrace coastal flooding rather than trying to prevent it from occurring. For instance, the study proposes that the state make room for wetlands in order to increase its capacity to withstand flooding and improve overall environmental and water quality. Other more specific suggestions include converting the land currently occupied by the world-famous Ala Wai Golf Course into wetlands and areas for wetland farming; creating a “South Shore Promenade” on the Honolulu waterfront to connect a network of existing and proposed shoreline green spaces that is currently fragmented and highly vulnerable to a myriad of hazards such as sea level rise, flooding, groundwater inundation, erosion storm surges and tsunami damage; and creating an elevated pedestrian promenade that would allow for unhindered water flow and protect wetland habitats.

“These catalytic sites will act as soft defense mechanisms against sea level rise, allow for indeterminacy, increase biodiversity, provide ecosystem services, and at the same time, create livable and accessible urban waterfront and place amenities for all people,” said Stilgenbauer, principal investigator of the UHCDC study. “This study contributes to help merge the seemingly conflicting goals of economic development, ecological performance, and urban place-making into mutually beneficial, resilient relationships.”

UHCDC’s comprehensive two-year study serves as a visionary tool for federal, state and city leaders

“In contrast to many scientific sea level rise and climate change studies, which often paint doomsday scenarios, our project highlights opportunities intrinsic to an inevitable need to plan for the adaptation of our coastal urban fabric throughout the remainder of the century,” she added.

Headquartered at the UH Mānoa School of Architecture, the UHCDC is a collective of faculty, staff, students and allied professionals representing multiple disciplines. The group provides proof of concept services in strategic planning, city and regional planning, master planning, community engagement, landscape and ecological design, architectural design, development studies, engineering studies, interior design, furniture design, graphic design, service design, social science, and user research.

“I’m thrilled that Stilgenbauer’s team leveraged the modeling that our researchers produced in 2018 depicting the footprint of sea level rise impacts on O‘ahu this century,” said Chip Fletcher, associate dean and professor in UH Mānoa’s School of Ocean and Earth Sciences and Technology (SOEST). “It has always been our goal that experts in other disciplines would build on our products. Interdisciplinary thinking such as this, needs to be at the heart of solutions to protect our communities from the increasingly dangerous effects of climate change.”