Tamagawa Josui in Modern Society
This project has another goal. That is to discover the unknown value of Tamagawa Josui. Experience the rich biodiversity of Tamagawa Josui and learn its historical and cultural values. Looking back from the past to the present, you will be able to think of ways to make Tamagawa Josui more attractive and valuable in today's society.
Photo: Karoku Kato
Tamagawa Josui’s Value Today
Safe Zone & Pathway for Creatures
Tamagawa Josui, which runs through the Kanto Plain, has become a "place of refuge" for living things whose homes have been deprived of by development, and a "pathway" for animals to travel from the mountains to the city.
Place where People and Nature Meet and New Activities Begin
Tamagawa Josui's mysterious charm has always attracted people. A variety of events and activities take place there.
Museum in Nature
If you look closely, you will be surprised that the world you don't know is spreading in the immediate vicinity. Tamagawa Josui is a "walk and enjoy museum" where you can experience nature and learn about its history.
Artery Created by Water and Green
Tamagawa Josui flows through the ridgeline and reaches the city center. It runs through the middle of the Kanto Plain east and west and connects the ruins of Edo Castle, Shinjuku Gyoen, and Meiji Jingu. It is like a flow of arteries, supporting the life of many creatures.
Water taken from the Tama River in Hamura flows to Kodaira observatory. From there downstream, highly treated sewage water flows. The treated water going through the underground waterway is released from Asama Bridge to the Kanda River and flows into the sea. If we can build a future that values nature, we may see migratory fish, such as ayu, swimming in Tamagawa Josui someday.
Refugee for Creatures
The Tamagawa River watershed, which connects the Tama Mountains and the city center, is a habitat for a variety of wildlife, including endangered species. People can't enter the waterways, which makes them a paradise for living things. It became an evacuation site for small creatures that had been deprived of their habitat by post-war residential development.
Produced based on observation data from organizations engaged in activities related to Tamagawa Josui. Many people volunteered to create fun illustrations. (Published by a local group Chimukui in 2013)
Tamagawa Josui Connects People and Nature and Became a Place Where Activities Emerge
The water of Tamagawa Josui is not used as drinking water anymore. Instead, the area around the stream is preserved as green space. Parks and promenades were made along with the flow, and people enjoy visiting there. Also, a variety of events are held on weekends and holidays.
Since the Edo era, Tamagawa Josui has changed its appearance as people's lifestyles have changed. In the 1960s, the government planned to fill in the entire Tamagawa Josui and make a highway there. But thanks to strong opposition from the public, most of the waterway was able to survive. This precious green corridor was protected by people's will. Today, this waterway provides citizens of Tokyo valuable nature from the Tama mountain area. Our involvement will be inevitable for this waterway to remain as it is.
A Museum to Learn Valuable Historic Sites and Nature
Since the Jomon period (about 10,000 years ago), the Kanto Plain has been a land of unpopulated barren fields. Tamagawa Josui has enabled a wide range of farming in the Kanto Plain. Populations of the area have grown, and major historical changes have taken place.
Tamagawa Josui is a waterworks made by Tamagawa brothers in 1653. The rapid population growth in Edo caused a severe water shortage and the town needed a waterway from the west. Tamagawa Josui is about 43 km from the water intake at Hamura to Yotsuya Okido in Tokyo. The height difference between the starting point and the endpoint is only about 90 meters. It is a miracle that the technology at the time made it possible to pass water through such a gentle slope. It is because Tamagawa Josui was built using high-quality building techniques.
You can learn about nature, architecture and the history of the area by walking through Tamagawa Josui.