A path to return the memory of water - Togura Town, Nagano Prefecture, mid-1990s

A path to return the memory of water - Togura Town, Nagano Prefecture, mid-1990s
In the mid-1990s, Japan was in the midst of a period of recession and pollution-related difficulties. Waves of urbanization and sewerage system development swept into rural areas, and miscellaneous domestic wastewater began to permeate into mountainous farming communities. The reality was that rice paddies and agricultural waterways were being affected by domestic wastewater and chemical fertilizers, polluted by organic matter and pesticides, and the ecosystem was quietly being eroded. Against this backdrop, the town of Togura in Nagano Prefecture has produced a small miracle that weaves together tradition and technology.

In this town, an agricultural canal was diverted and a filtration system was installed, in which charcoal was laid between layers of crushed stone. As the water gently passes through the device, the porous nature of the charcoal and the microorganisms absorb and decompose organic matter and chemical residues, thereby promoting purification. This method, which requires no power and no chemicals, is a recycling-oriented technology that maximizes the use of local materials and the effects of nature.

The results of this practice were clear. Genji fireflies, which had disappeared in the past, began to light up again in the clear stream. Fireflies became a symbol of the cleanliness of the water and a symbol of the restoration of nature for the local residents. Eventually, the used charcoal was crushed and returned to the fields as a soil conditioner. This series of cycles was more than a simple purification technology; it was like a pathway between nature and daily life.

This attempt can be regarded as a pioneering case in which the philosophy of sustainability, which has increased since the Rio Earth Summit in 1992, was embodied at the local level. In terms of locally based technology, soil purification and water quality improvement techniques using charcoal are still the subject of research, and are in line with the Forestry Agency and the Ministry of the Environment's policy of promoting the use of old trees. For example, water purification using activated charcoal and charcoal is attracting attention as a low-cost removal technology for agricultural water and urban wastewater treatment.

I believe that the story of Togura Town is a "poem of landscape revival" in which the voice of water was restored not by grand facilities or large capital investment, but by the use of familiar materials and the ingenuity of human knowledge.