Building up and maintaining local capacity depend naturally on the self-governing of people, but they also depend much on supports from the outside, on the social circumstances and on the appropriateness of people's decisions themselves. In early modern, people in Kiryu in Gumma prefecture (one of the key industrial spots in Japan, including Isesaki and Ashikaga of Northern Kanto and Hachioji of West Tokyo as well as Toyota in Aich prefecture) had textile technology as high as Nishijin's, operating about 150 water wheels once only in its Shinshuku and Sakaino areas for thread twisting. They had a strong endogenous capacity having installed factories, railroads and a textile college all by themselves. After WWII, they steered their business to cheaper products, which brought them into total decline. This is quite in contrast to Nishijin which has been maintaining their status so far by sticking to high-quality products. These imply that once miss-defining and misjudging the future, even a strong local autonomous capacity has to decline.
     Now that we are in the time to revisit renewable energy utilization for getting rid of global warming, these rural towns of rich water resources have a chance to reconstruct themselves as a "water city", redefining their potential for the sustainable future, including their urban renovation for green tourism, like Lowel, Ma. of United States.
     In this research, we organize a university-local people collaboration to unveil the past achievements in water utilization and their endogenous urban development in the early modern period through actor network analysis and to conduct a conceptual design for the rebirth of a once active local city into a "sustainable water city" with a new self-definition of their role for the future. This project also aims at making the process of research a process of building up local actors' endogenous capacity for the urban rebirth, of which people will become proud at home and abroad as one of the precedent case of actions against global warming.

1. Summary
1-1 Background and target
This project aims to reevaluate the characteristics of local regions and the formation of cities through research on the history of water use in so-called “water cities,” cities whose construction was strongly influenced by rivers and canals. In carrying out the project, we established a collaborative framework with the local people living and working in the area. Through collaborative research, we reveal present regional problems and newly found regional values, and aim to establish a methodology for creating a future vision of the city by utilizing natural energy and regional resources for regional revitalization, which will contribute to proactive efforts by local residents.

1-2 Method
We studied Kiryu City, Gunma Prefecture. Kiryu developed in tandem with the silk industry, where water mills were used in textile production. We conducted the following activities.
- A survey on reproducing the channel network and the history of water mill use
- Establishing a collaborative framework, the “Suito Kiryu Collegium” (“suito” meaning “water city”). A professor from Gunma University, officers from private corporations, NPO staff, city officials, and other diverse individuals participated
- Sharing the results of the survey and knowledge (introduction of historical materials related to the local history, including the history of water use among attendees); exchanging opinions on utilization of historical resources and sightseeing PR measures at the collegium
2. Results
Our research and activities yielded the following results
- Reproduction of the channel network and a survey on the history of water mill use
＞ We reproduced Kiryu's channel network (mainly the Akaiwa Channel and Ozeki Channel) for the year 1873 (Meiji year 6), when water mills were used.
＞ Broadly, it is known that many of Kiryu’s water mills were installed in Akaiwa Channel. Our research revealed that a larger number of water mills were installed in Ozeki Channel before the Edo era.
＞ We have shown that the modern factory based on hydraulic power constructed by Nippon Textile Co., Ltd. in Kiryu in the latter half of the Meiji era is highly likely to have been designed with reference to a cotton fabric factory in the northeastern United States with a hydraulic power system.
＞ We showed that the industrial revolution progressed here using hydropower instead of fossil fuels, and that Kiryu is in the final chapter of its history.

- Survey of historical materials provided by participants at the Suito-Kiryu Collegium
＞ We received about 30,000 old photographs of the sights in and around Kiryu, provided by the participants, and surveyed some pictures of unknown origin.
＞ In the survey, we held a “Kiryu Old Photography Survey Meeting” with elderly people, looked at photographs together, and determined where each photograph was shot.
- Hosting of parent-child participation events
＞ By using some of the results of Kiryu Old Photography Survey Meeting, we held a parent-child participation event, the "Kiryu History Expedition Team." In the event, we toured and observed historic locations in Kiryu on an electric bus with parents and children.
- Creating a path towards revitalization as Suito-Kiryu (conducted concurrently alongside another project)
＞ We studied measures to conserve Kiryu’s historic features while utilizing Kiryu's channels in a feasibility study for small-scale hydropower generation (implemented by the Japanese Ministry of Economy, Trade and Industry).
＞ Although subsidies will need to be utilized, we found that activity is possible if two conditions are met.
(Condition 1): If a 1 kW small hydraulic power generation system can be installed at a cost of about 3.7 million yen
(Condition 2) If water intake during rice planting can be maintained throughout the year
- Symposium
＞ We held a symposium "Urban image of Kiryu, seen in the history of Suito" with the aim of disseminating the results of the research and activities to the citizens of Kiryu.