Toei Ōedo Line

The Ōedo Line is the first Tokyo subway line to use linear motor propulsion (and the second in Japan after the Osaka Metro Nagahori Tsurumi-ryokuchi Line), which allows it to use smaller cars and smaller tunnels (a benefit similarly achieved by the Advanced Rapid Transit system manufactured by Bombardier). This technology, though, is incompatible with other railway and subway lines, which can only operate with vehicles utilizing conventional rotary motors, thus preventing Ōedo Line trains from operating through services onto them. Although vehicles with rotary motor propulsion can technically operate on the Ōedo Line, its smaller tunnels and loading gauge prevents such occurrences, hence making the Ōedo Line the first self-enclosed subway line in Tokyo in over 40 years, and the first and to date only such line operated by Toei, although there is a track connection to the Asakusa Line that can be used only by Class E5000 locomotives. The line is deep (as low as below ground at points) through central Tokyo, including three underground crossings of the Sumida River. Originally budgeted at ¥682.6 billion and 6 years, the construction ended up taking nearly 10 years and estimates of the final cost of construction range from the official ¥988.6 billion to over ¥1,400 billion, making it the most expensive subway line ever built at that point. However, stages 1–3 of Singapore's Downtown MRT line, completed in 2017, are 2.84 times as expensive, at 33,669.5 compared to 11,571.8 US dollars per kilometer after adjusting for inflation and international price differences. Phase 1 of New York's Second Avenue Subway, also completed in 2017, is over 5.5 times costlier per kilometer at 2,308.3 compared to 416.3 price-adjusted US dollars per kilometer. Ridership projections originally estimated 1 million users daily, a figure scaled down to 820,000 before opening. At the end of 2006, the line was averaging 720,000 passengers/day. However, its ridership has increased by about five percent each year since its opening, following new commercial and residential development around major stations such as Roppongi and Shiodome. According to the Tokyo Metropolitan Bureau of Transportation, as of June 2009 the Ōedo Line was the fourth most crowded subway line in Tokyo, at its peak running at 178% capacity between Monzen-Nakachō and Tsukishima stations. There are plans to extend the Ōedo Line westward from its current western terminus at Hikarigaoka Station through to a new terminus in Ōizumigakuenchō, north of Ōizumi-gakuen Station (on the Seibu Ikebukuro Line) then later towards Higashi-Tokorozawa Station (on the Musashino Line). The first segment to Ōizumigakuenchō, which will include three new stations in Doshida, Oizumimachi, and Oizumigakuencho, is expected to open around 2040 at a cost of 160 billion yen. Following the awarding of the 2020 Summer Olympics to Tokyo, there had been speculation regarding the addition of another to the proposed extension in order to extend the line to Niiza where the shooting range for the Olympics was to be located. A decision regarding this matter was expected in 2015. ==Services==

The Ōedo Line runs in a loop around central Tokyo before branching out towards Nerima in the western suburbs, meaning the line is shaped like a figure 6 lying on its side. It is not a true loop line: trains from the western Hikarigaoka terminus run anticlockwise around the loop and terminate at the intermediate Tochōmae Station facing towards Hikarigaoka, and vice versa. The arrangement is very much like the London Underground Circle Line since 2009, but does not share any track segments with other lines. The full trip from Tochōmae around the loop and onward to Hikarigaoka takes 81 minutes. Trains operate once every three to five minutes during rush hours, and once every six minutes during off-peak weekday hours, weekends and holidays. ==History==

Planning The Ōedo Line was first proposed in 1962 as a route running from Roka-kōen through Hōnan-chō, Shinjuku, Kasuga-chō, Umayabashi, Fukagawa, and Tsukishima, and onward to Azabu under the Urban Transportation Council Report No. 6 (都市交通審議会答申第6号). However, Keio opposed the plan on the grounds that the proposed route would traverse a key Keio Bus operating area and that the introduction of a subway would have a substantial adverse effect on its bus business. In response, on March 27, 1964, the Urban Transportation Council accepted Keio’s proposal and revised Line 9’s route between Roka-kōen and Shinjuku to follow a quadruple-tracked Keio Line alignment via Sakurajōsui, Meidaimae, and Hatagaya. However, as a result of the abrupt change in social conditions following the 1973 oil crisis and the deterioration of the Transportation Bureau’s financial situation, the construction plan was temporarily frozen from mid-1976. Construction and opening On June 1, 1986, construction begins between Hikarigaoka and Nerima. ==Stations== All stations are located in Tokyo. ==Rolling stock==

• Toei 12-000 series 8-car EMU trainsets • Toei 12-600 series 8-car EMU trainsets Oedo Line trains are housed and maintained at the Kiba depot, located underneath Kiba Park to the southeast of Kiyosumi-Shirakawa Station. Prior to the completion of the Oedo Line loop in 2000, servicing was performed at a depot near Hikarigaoka Station. Major overhaul work for Oedo Line trains is performed at the Magome depot, located south of Nishi-Magome Station on the Toei Asakusa Line. Oedo Line trains access this facility using a connecting tunnel to the Asakusa Line near Shiodome Station. Because of differences in infrastructure and technology used preventing trains on either line from accessing the other, a special Toei Class E5000 locomotive powers these ferry runs during overnight hours when the subway is closed. ==Noise complaints==

The Ōedo line is one of the noisiest train lines in the world, with decibel levels reaching 90 decibels frequently along the line. However, during the COVID-19 pandemic, noise levels have reached to over 105 decibels. The train line's President states that infection is a more significant concern [than hearing damage], and therefore train's windows are kept open to increase ventilation, which caused a number of complaints. As of April 2023, windows continue to be kept open to reduce the risks of Covid-19 transmission. The cause of the Ōedo line's high noise levels lies in construction constraints such as preexisting infrastructure and the need to build deep tunnels, resulting in low-radius curves and small tunnels. == Notes ==