Report pinpoints state facilities most at risk for sea level rise | News, Sports, Jobs

According to the annual sea level rise adaptation report released last month by the state Office of Planning and Sustainable Development and the state Department of Business, Economic Development and Tourism, the state Department of Education has the greatest number of vulnerable structures.

OPSD’s Coastal Zone Management Program completed one of three phases of work relating to sea level rise adaptation in Hawaii. Adaptation planning takes place over decades and is constantly evolving as conditions change and process, but the report is annual and includes exposure assessments and recommendations.

“This initiative is an on-going and dynamic process,” the report said.

Phase 1, which was completed, involves making assessments and taking inventory of existing and planned state facilities within coastal areas that are or will be vulnerable to sea level rise, flooding impacts and natural hazards.

Toppled coconut palm stumps and pieces of broken concrete walkway are lapped by waves on the beach fronting the Kaanapali Alii in September.

Over the next 30 to 70 years, homes and businesses located near the shoreline will be impacted by sea level rise, according to the 2017 Hawaii Sea Level Rise Vulnerability and Adaptation report.

About 130 structures in Hawaii would be chronically flooded with 3.2 feet of sea level rise, calling for state and county agencies to consider long-term adaptation measures as early as possible, such as relocating infrastructure, which would save money down the road.

Using the 2017 report’s calculations, sea level rise exposure areas for the 0.5-foot, 1.1-foot, 2-foot and 3.2-foot scenarios were used for analysis in the 2021 report of three chronic flooding hazards: passive flooding, annual high wave flooding and coastal erosion.

There are roughly 13 state facilities on Maui in the 0.5-foot sea level rise zone, about 31 in the 1.1-foot range, about 34 in the 2-foot range and 34 in the 3.2-foot zone.

The National Oceanic and Atmospheric Administration’s 6-foot projection was also used in the report, which showed that roughly 51 state facilities across the Valley Isle were in this sensitive area.

Molokai has an estimated 69 state facilities in the sea level rise scenarios. Lanai has 39.

The report also broke down vulnerable facilities by department/agency in the 3.2-foot scenario, showing that the state Department of Education has the greatest number of vulnerable facilities, followed by the Department of Transportation and Department of Land and Natural Resources.

Of the 25 agencies with facility management responsibilities, 20 agencies have vulnerable facilities in the 3.2-foot scenario, the report said.

It is noted in the data that the total number is an underestimate due to underreporting, but among the 275 state structures listed, most agencies have vulnerable facilities in the 6-foot scenario.

On Maui, specifically, DOE buildings are the most vulnerable to sea level rise, flooding impacts and natural hazards, followed by DOT’s Harbors Division. On Molokai, the most vulnerable state facilities belong to the DOT.

With 3.2 feet of sea level rise expected by 2100 or sooner, more than 11 miles of major coastal roads around Maui would become impassable, jeopardizing critical access to and from many communities.

The findings indicate that the impacts of sea level rise on state facilities will be statewide, but with impacts concentrated on Oahu.

The report also identified “critical facilities” throughout the state — with functions such as agriculture, transportation, communications or health care — that include both public and private management.

Every facility was analyzed with the 3.2-foot sea level rise scenario. Among the 195 in the report, only 20 are managed by the state, which “underscores the need to consider the vulnerabilities of out-of-scope assets, as well as coordinate with non-state government entities, when assessing the effects of sea level rise on state facilities.”

One of the core categories was water, waste and wastewater systems, which was the category with the most amount of critical infrastructure in vulnerable areas. Among the 82 facilities, 81 were under the county or privately managed.

Next were energy and communications at 19 and 18, respectively, with all but one structure privately managed.

Now that the Hawaii Coastal Zone Management Program has completed the first phase, they will continue on to Phase 2, which involves more site-specific vulnerability assessments in order to prioritize adaptation actions.

“Due to numerous limitations including funding and capacity, it is not feasible to adapt all vulnerable facilities at the same time, therefore it is necessary to prioritize facilities in need of adaptation,” the report said.

Prioritization is determined through conducting more detailed assessments and creating a ranking system.

Phase 3 is about identifying several mitigation and adaptation strategies for the identified vulnerable facilities.

Since there is no “one-size-fits-all solution,” the report said that this phase would require the state to identify a variety of acceptable strategies that would be applicable in a variety of settings. These strategies would range from nature-based solutions to shoreline hardening while also incorporating short-, mid- and long-term planning.

“Additionally, the process of adaptation is inherently continuous as conditions change and understanding evolves,” the report said. “With the Phase 1 high-level inventory completed, OPSD-CZM is looking towards Phase 2 and facilitating in-depth, localized vulnerability assessments in order to prioritize facilities in need of adaptation and mitigation strategies.”

To view the whole document, visit climate.hawaii.gov/hi-adaptation/climate-change-reports/.

* Dakota Grossman can be reached at dgrossman@mauinews.com.