Unlike the largely above-ground Tokaido Shinkansen that runs a similar but more coastal route, 86 per cent of the maglev line's 286-kilometre course between Tokyo and Nagoya would be in tunnels, necessitating significant excavation work. Just 8.9 km of the tunnels are set to pass through Shizuoka Prefecture. Amid controversy over the line's tunnels passing through the prefecture, Kawakatsu and local communities have pushed back over environmental issues, including what is known as the "water problem" involving the effects of construction on the Oi River. Opposition in Shizuoka Prefecture emerged from fears the planned tunnel construction for the line could adversely affect the overall volume of water that passes through the river. JR Central has not yet been able to start tunnel construction despite the approach of the initial targeted start date. [...] But as one door opened, another shut in the form of a report from a Ministry of Land, Infrastructure, Transport and Tourism panel in December that acknowledged the development could damage the ecology of mountain ranges known as the Minami Alps, or the Southern Alps, which run from central Nagano Prefecture and down through Yamanashi and Shizuoka prefectures.