Koichi Takada's career began with a river. The Tokyo-born architect grew up in the 1970s, living a stone's throw from the scenic banks of the Tama River in the west of the capital. Takada spent his youth enjoying nature, catching shellfish or koi and releasing them back into the river.

However, the formidable grip of postwar urbanization was palpable in the city. As a child, Takada observed as skyscrapers, train stations and modern infrastructure emerged against the backdrop of the placid rice fields and water systems near his home.

"(The) river was my playground, but as a child I could (already) understand that when the river got polluted, all the fish disappeared," he says. "I was surrounded by incredible nature, but it was disappearing. This so-called commercialization was taking away a basic but fundamental living environment."