In order to adopt the brushwood breakwater, we were able to institute a system for providing thinned-out brushwood. Brushwood is produced through managing the coppices (deciduous broad-leaved forest), such as thinning and undergrowth mowing. Most of the coppices in the watershed, however, were abandoned and wasted for over 30 years. Consequently, the life and industry using the coppices have long been lost.
Brushwood supply from the coppices in the catchment area can only be achieved by creating a new industry through close tie with the local community. We needed an industry that provides the lake reviving project (brushwood breakwater) with fascines of brushwood collected through the coppice management in the catchment area. For this reason, we called on various self-employed businesses and companies who participated in the Asaza Project to organize the “Kasumigaura Brushwood Fascine Association Ltd.”. The eco-restoration action prepared the way for creating a new industry. The Association is committed to managing 20 ha of different forests every year. Their activities contribute to not only the nature conservation but also a positive social impact, i.e. job creation.
In the past, administrative bodies and community groups operated forest management in the catchment area. Nevertheless, their activities covered areas of only limited extent, far from the necessary spread of action required for a total lake-wide vision. These individual efforts can now join hands with the new industry such as The Kasumigaura Brushwood Fascine Association Ltd. to evolve the localized actions into more diffuse and extensive ones. Total watershed expansion of the eco-restoration efforts vitally require the tie-up with a locally spread industry. The Kasumigaura Brushwood Fascine Association Ltd. is an enterprise devoted to forest management and fascine production on the basis of biodiversity conservation and headwater protection.
The Asaza Project is also engaged in a wide spectrum of other activities in various locations, including reed field restoration in partnership with fisheries cooperatives, biotope creation in fallow paddy fields in cooperation with farmers, a watershed management system construction linked with a school biotope network and the internet, and a nature restoration program with the influent river tying up the municipalities and the Ministry of Land, Infrastructure, and Transport.
The crucial element in creating a circulation in society is that each action and technology does not fall into self-containment. We need to evolve our efforts so that each action will spawn another in a chain-reaction manner to form a network. By this way, public works projects can also exert a cross-boundary ripple effect over the entire region (Fig. 8).