If the Ohi nuclear reactors plunged into a Fukushima-style meltdown, the only route for escaping or for sending help would be a winding, cliff-hugging road often closed by snow in winter or clogged by beachgoers in summer.

Radioactivity from such an accident at the plant in western Japan could contaminate the country's biggest freshwater source, Lake Biwa, which serves more than 14 million people.

Still, Japan's government has chosen to lift its post-Fukushima nuclear freeze and restart two reactors at Ohi, even though construction of an alternative route to the facility is barely on the drawing board and despite the lack of any firm contingency plans for the water source.

The government is pushing hard to get some reactors back online before energy-hungry summer months, despite much public opposition.