Kansai Airports and Hannan City to collaborate on “the Osaka Bay Sea Forest (Seaweed Beds) Conservation and Restoration Project“

Kansai Airports and Hannan City will work together to create a rich marine environment through collaboration between the local communities and the airport as “the Osaka Bay Sea Forest (Seaweed Beds) Conservation and Restoration Project”. Kansai Airports is also pleased to announce that this initiative was registered to the “TEAM EXPO 2025” Program Co-Creation Challenge of the Osaka-Kansai Expo.

The year 1970, when the previous Osaka Expo was held, was when the economy was rapidly growing and when the Osaka Bay area experienced environmental changes, such as water quality deterioration, due to population growth and industrial development. In addition, while land development by earth filling greatly supported the economic growth, natural beaches and shallow waters, such as seaweed beds and tidal flats, were lost. Against this historical backdrop, Kansai International Airport was planned and built on the sea about 5 km off the coast of Senshu in the Osaka Bay, with the policy of becoming "a pollution-free airport coexisting with the communities". The plan aimed for harmony with the marine environment from  the outset, and gently sloping rubble mound seawalls were used for the seawalls of the airport island and we have actively planted seaweed to create rich seaweed beds. Hannan City has the largest eelgrass bed in Osaka Prefecture, and has conducted regional learning using the sea, conducted the first oyster farming in the Osaka Bay, and became the first municipality in Kansai region to be certified under the Yokohama Blue Carbon Offset System for “wakame” seaweed farming. 

The city has also been actively working to preserve the marine environment and to utilize resources, for example, by obtaining the certification under the J Blue Credit System of the Japan Blue Association, a government-approved organization established in 2020 for a blue carbon offset certification for “eelgrass”.

Now, 50 years after the Osaka Expo, we hope that the seagrass beds that have been nurtured together with Kansai International Airport will contribute to environmental conservation activities with the local communities and help build the future of the entire Osaka Bay.

Given the global focus on environmental issues and the values of blue carbon, this project, co-created by Kansai Airports and Hannan City, is expected to generate synergy effects, and by using this as a model case to spread it to other areas laterally in the whole country and the world, we aim to prevent global warming, which is an environmental issue in and out of the country, and to protect biodiversity. We will also contribute to achieve the carbon neutrality as a "Sea-Expo”, by sharing the results of this project with Japan and the world through the Osaka-Kansai Expo.

Overview of the registration for the TEAM EXPO 2025 Program Co-Creation Challenge of the Osaka-Kansai Expo
Osaka Bay Sea Forest (Seaweed Beds) Conservation and Restoration Project
To create a rich marine environment through collaboration between local communities and the airport.

1. Seaweed transplant projects by the local communities and the airport
2.  Enhancing the values of the Osaka Bay by sharing knowledge to create seagrass beds
3.  Educating the next generations to improve the marine environment

The Initiatives by Kansai Airports
In order to contribute to the creation of a habitat for marine life in the Osaka Bay, Kansai Airports is actively working to create a rich seaweed bed environment around the airport islands. When Kansai International Airport islands were built, various ingenuity was actively utilized to adopt gently rubble mound seawalls to most of the seawalls. Even now, by continuing our efforts to maintain and expand a good seaweed bed environment, about 20% of the seaweed beds in the Osaka Bay is at Kansai International Airport, providing habitat for a variety of fish and shellfish. In December 2022, the amount of CO2 absorbed by seaweed growing on the seawalls around the airport islands was quantified and KAP received JBlue Credit Certification*.

KAP also works with people in the fisheries sector through “the Osaka Marine Beautification and Safety Association Secretariat”, an NPO, to collect garbage deposited and floating in the waters of Osaka Prefecture and washed ashore. KAP also contributes to the conservation of the ecosystem of the Osaka Bay by collecting an annual total of approximately 1,300m3 of garbage, including marine plastic waste.

The Initiatives by Hannan City
Hannan City has the largest eelgrass bed in Osaka Prefecture and plays an important role in protecting the environment of the Osaka Bay. Triggered by the National Amamo (Eelgrass) Summit 2018 in Hannan, elementary school students participated in “the G20 Osaka Summit Partners’ Program”, and regional learning programs utilizing the ocean (such as dragnet fishing experience and environmental education) are provided to children from an early age in cooperation with the fishing industry. In FY2019, the city was selected in the regional activity section of “the Ocean Education Pioneer School Program” and was certified for “the Yokohama Blue Carbon Offset System” for the first time in Kansai as an initiative by fishers’ associations, including oyster farming, which was the first in the Osaka Bay, and seaweed farming. In 2021, the city was registered as part of the "Zero Carbon City Declaration" and the local SDGs "the Circular and Ecological Economy" by the Ministry of the Environment. In 2022, the city joined the 30 by 30 Alliance for Biodiversity. Furthermore, in May 2022, the city was selected as a "SDGs Future City" and a "SDGs model business district". And the city's Co Benefit Creation Project will be presented as a carbon-neutral initiative utilizing local resources such as beach space, at the Zero Carbon International Forum to be hosted by the Ministry of the Environment in March 2023. In February 2023, the “eelgrass” was certified for blue carbon offset under the J Blue Credit* system. In addition, the city is currently working with various organizations and companies in Hannan City as co-creation partners to undertake co-creation activities on the occasion of  the Osaka-Kansai Expo.

*Credits certified, issued and managed by the Japan Blue Economy Association (JBE). The credits are certified and issued after review and verification by an independent third-party committee.