Case Studies

Fish came back to a river

Mie, Japan

Asechi Usui No. 2 main line, which is an approximately 5 km long river that flows through the center of the Yokkaichi city, is called by the local people Asechi River (hereinafter, referred to here as “Asechi River”). Up to before World War II fireflies were seen near Asechi River, but with population growth pollution increased and sludge has gradually built up in the river. Complaints to city hall about the stench led to dredging of sludge every three to four years as a countermeasure, but this did not stop the progression of the pollution. Local volunteers decided to try to clean the Asechi River on their own, and starting in 2000 began implanting the use of EM (Effective Microorganisms). One year from the start of their activities, they confirmed that the stench was alleviated and the sludge had decreased. The local residents’ association was impressed by this result and they started to cooperate in using EM. Gradually the circle of this activity grew, residents and businesses along Asechi River also participated, and this led to community-wide activities. As the activities increased so too did the results, and now clean sand is visible between the aquatic plants that grow in the riverbed

Five years from the start of this activity fish have returned to the river, and local people released colored carp into the water and enjoy watching them now.

In 2008, eight years after the activities began, Ayu (sweetfish) also been identified swimming upriver, and this has been widely reported in the local media.

Comment from the previous mayor of Yokkaichi City

From Chunichi Newspaper on October 22, 2008
An article about Ayu fish coming back to Asachi River

Asechi River flows through the very center of the city, and nearby residents often complained loudly about it. In the summer, people complained that, “It stinks!” If you go toward to estuary, there are indeed mountains of sludge. People begged that we “Do something about it!” We got rid of the sludge at a cost of 20-30 million yen every three or four years. However, I wondered whether we should use our tax money to do that. In 2000, as I recall, I wondered whether we could clean up the river introducing EM Bokashi fermented mud balls. Then, the municipal government would no longer need to spend a tremendous amount of money just to get rid of the sludge. Will it really work? I wondered, and thought that we won’t know until we actually try it. Volunteers asked me to let them do it on their own, and told me that definitely the conditions in the river would improve. So we asked them to go ahead. The most surprising thing is that the Japanese government requires the most money and authority to take care of the rivers, but those kinds of actions and national undertakings were done through the power of local citizens, This is simply revolutionary. At first, this was done by volunteers, but after a couple of years members of the local resident’s association thought, “This looks very likely to succeed” and they also wanted to help. Two or three years after that, the city started to think they needed to be part of this, and seriously got involved.
So support for the volunteers steadily began to swell. Also, the results are quite visible. This would be a truly great project. Far from citizens’ activities and administrative and bureau business expansion moving in opposite directions, we see them moving in the same direction, doubling and tripling the effectiveness. We call this “collaboration” and I want us to focus on this. This case is the most stunning example of the success of such joint efforts.

※ Here we introduce the tape transcription of an interview with Mr. Tetsuo Inoue, who was mayor
of Yokkaichi city in 2008, about the restoration project in Asechi River at that time.

(Updated in 2008)