There are significantly more vulnerable state facilities along the coast as the impacts of sea level rise are also increasing due to global climate change, especially on Maui and Oahu, according to a recent report from the Water Management Program. Hawaii Coastal Area posted last month.
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 most vulnerable structures.
OPSD’s Coastal Zone Management Program completed one of three phases of work related to adaptation to sea level rise in Hawaii. Adaptation planning takes place over decades and is constantly evolving as conditions change and processing, but the report is annual and includes exposure assessments and recommendations.
“This initiative is an ongoing and dynamic process,” the report said.
Phase 1, which has been completed, involves conducting assessments and taking an inventory of existing and planned state facilities within coastal areas that are or will be vulnerable to sea level rise, flood impacts, and natural hazards.
Over the next 30 to 70 years, homes and businesses located near the coast will be affected by sea level rise, according to the 2017 Hawaii Sea Level Rise Vulnerability and Adaptation Report.
Some 130 structures in Hawaii would be chronically flooded with a 3.2-foot sea level rise, requiring state and county agencies to consider long-term adaptation measures as soon as possible, such as infrastructure relocation , which would save money in the future.
Using the calculations from the 2017 report, the areas of exposure to sea level rise for the 0.5-foot, 1.1-foot, 2-foot, and 3.2-foot scenarios were used for analysis in the 2021 report from three chronic flood hazards: passive flooding, annual high wave flooding, and coastal erosion.
There are approximately 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-foot zone. ,2 feet.
The National Oceanic and Atmospheric Administration’s 6-foot projection was also used in the report, which showed that approximately 51 state facilities on Valley Isle were in this sensitive area.
Molokai has an estimated 69 state facilities in the sea level rise scenarios. Lanai is 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 most vulnerable facilities, followed by the Department of Transportation and the Department of Land and Natural resources.
Of the 25 agencies with facilities management responsibilities, 20 agencies have vulnerable facilities in the 3.2-foot stage, according to the report.
It is noted from 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 stage.
On Maui specifically, DOE buildings are the most vulnerable to sea level rise, flood impacts, and natural hazards, followed by DOT’s Division of Ports. On Molokai, the most vulnerable state facilities belong to DOT.
With a sea level rise of 3.2 feet expected in or before 2100, more than 11 miles of major coastal highways around Maui would become impassable, jeopardizing critical access to and from many communities.
The findings indicate that sea level rise impacts 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— that include both public and private management.
Each facility was tested using the 3.2 foot sea level rise scenario. Of the 195 in the report, only 20 are administered 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 sewage systems, which was the category with the largest amount of critical infrastructure in vulnerable areas. Among the 82 facilities, 81 were under county or private management.
Power and communications followed at 19 and 18, respectively, with all but one structure privately managed.
Now that the Hawaiian Coastal Zone Management Program has completed the first phase, they will move on to Phase 2, which involves further site-specific vulnerability assessments to prioritize adaptation actions.
“Due to numerous constraints, including funding and capacity, it is not feasible to retrofit all vulnerable facilities at the same time, so facilities needing retrofitting need to be prioritized.” the report said.
Prioritization is determined by conducting more detailed assessments and creating a ranking system.
Phase 3 is about identifying various mitigation and adaptation strategies for the identified vulnerable facilities.
As 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 strengthening, while incorporating short-, medium-, and long-term planning.
“Furthermore, the adaptation process is inherently continuous as conditions change and understanding evolves.” the report said. “With the Phase 1 high-level inventory completed, OPSD-CZM looks forward to Phase 2 and facilitates in-depth, localized vulnerability assessments to prioritize facilities in need of adaptation and mitigation strategies.”
To view the full document, visit climate.hawaii.gov/hi-adaptation/climate-change-reports/.
* Dakota Grossman can be reached at [email protected]