The is a

breakwater Breakwater may refer to: * Breakwater (structure), a structure for protecting a beach or harbour Places * Breakwater, Victoria, a suburb of Geelong, Victoria, Australia * Breakwater Island Breakwater Island () is a small island in the Palme ...

and

artificial island An artificial island is an island that has been constructed by people rather than formed by natural means. Artificial islands may vary in size from small islets reclaimed solely to support a single pillar of a building or structure to those tha ...

located in

Tokyo Bay is a bay located in the southern Kantō region of Japan, and spans the coasts of Tokyo, Kanagawa Prefecture, and Chiba Prefecture. Tokyo Bay is connected to the Pacific Ocean by the Uraga Channel. The Tokyo Bay region is both the most populous a ...

, adjacent to the

Tokyo Gate Bridge is a truss cantilever bridge across Tokyo Bay in Kōtō, Tokyo, Japan. It opened on 12 February 2012 with an estimated total construction cost of for the Stage II section of highway including the bridge.Official "flyer" shows Stage II includin ...

History

The Central Breakwater was first constructed in 1973 and has been used as a site for waste disposal from Tokyo since then, forming two

s in Tokyo Bay known as the and the . The islands had a combined area of 377 hectares in 2011 and are expected to ultimately reach an area of 989 hectares.

Jurisdiction dispute

Jurisdiction over the Central Breakwater islands was disputed between the

special wards are a special form of municipalities in Japan under the 1947 Local Autonomy Law. They are city-level wards: primary subdivisions of a prefecture with municipal autonomy largely comparable to other forms of municipalities. Although the autono ...

Koto Koto may refer to: * Koto (band), an Italian synth pop group * Koto (instrument), a Japanese musical instrument * Koto (kana), a ligature of two Japanese katakana * Koto (traditional clothing), a traditional dress made by Afro-Surinamese women * K ...

and Ota for 4 decades. Under Japanese law, any boundary dispute may be submitted to the prefectural government (in this case, the Tokyo metropolitan government) for resolution; a similar dispute with regard to the nearby

Odaiba today is a large artificial island in Tokyo Bay, Japan, across the Rainbow Bridge from central Tokyo. Odaiba was initially built in this area for defensive purposes in the 1850s. Reclaimed land offshore Shinagawa was dramatically expanded durin ...

and

Ariake Ariake (有明: "daybreak") may refer to: Places in Japan *Ariake, Kagoshima, a former town in Kagoshima Prefecture *Ariake, Kumamoto, a former town in Kumamoto Prefecture *Ariake, Saga, a former town in Saga Prefecture *Ariake, Tokyo, a district w ...

area was resolved in 1982 by splitting the area between the three special wards that claimed it. Koto has argued that the garbage used to create the landfill was hauled through Koto and that making the island part of the special ward would repay residents for their trouble, while Ota has argued that the site of the breakwater was historically used by Ota-based ''

nori Nori is a dried edible seaweed used in Japanese cuisine, made from species of the red algae genus ''Pyropia'', including ''P. yezonesis'' and '' P. tenera''. It has a strong and distinctive flavor, and is often used to wrap rolls of sushi or '' ...

'' cultivators, and that the island should be managed in coordination with nearby

Haneda Airport , officially , and sometimes called as Tokyo Haneda Airport or Haneda International Airport , is one of two international airports serving the Greater Tokyo Area, the other one being Narita International Airport (NRT). It serves as the primary ...

(which is part of Ota). The dispute is mainly considered an issue of brand image; jurisdiction over the island offers little practical benefit to the special wards, as fixed asset taxes on real estate are collected by the metropolitan government. On October 3, 2019

Tokyo District Court is a district court located at 1-1-4 Kasumigaseki, Chiyoda, Tokyo, Japan.Supreme Court of Japan websit東京地方裁判所の紹介Retrieved on August 7, 2011 See also *Judicial system of Japan The judiciary (also known as the judicial sys ...

ruled 79.3% of the Central Breakwater landfills to Kōtō Ward and 20.7% to Ōta Ward for multiple decades. Ota Ward stated that it won't appeal the ruling. Thus the 40 year dispute was closed. From December 17 to January 31, 2020 the public made 532 proposals for the town name of the west side to be incorporated in Ota Ward. On 1 June 2020, Reiwajima (令和島) became the official name. The east side of Koto Ward uses the name Sea Forest (海の森) which they were accustomed to.

2020 Summer Olympics

The Central Breakwater is one of the planned venues for the

2020 Summer Olympics The , officially the and also known as , was an international multi-sport event held from 23 July to 8 August 2021 in Tokyo, Japan, with some preliminary events that began on 21 July. Tokyo was selected as the host city during the ...

. The Inner Landfill will host the Sea Forest Cross-Country Course for equestrian events, while the Outer Landfill would have hosted the Sea Forest Mountain Bike Course but was eventually moved to

Izu, Shizuoka is a city located in central Izu Peninsula in Shizuoka Prefecture, Japan. , the city had an estimated population of 30,678 in 13,390 households, and a population density of 84 persons per km2. The total area of the city was . Geography Izu is ...

. The waterway between the two islands, named

Sea Forest Waterway The is a regatta venue for rowing (sport), rowing and canoeing, situated in Kōtō and Ōta, Tokyo, Ōta, Tokyo Bay, in Japan. History The venue was built for the 2020 Summer Olympics and 2020 Summer Paralympics, Paralympic Games. Construction ...

, will be used for rowing and kayaking events. The venues will be maintained as recreational areas after the Games.

References

{{Olympic venues equestrian Breakwaters Artificial islands of Japan Venues of the 2020 Summer Olympics Olympic equestrian venues Tokyo Bay Internal territorial disputes of Japan