Lake Kasumigaura (including Lake Kitaura) ranks second only to Lake Biwa in area (220 km2) and is first in total shoreline (250 km) from among all Japanese lakes. For the purpose of water utilization and flood control, the Kasumigaura Development Project surrounded the lake with a concrete revetment, which devastated the ecosystem by depleting the lake-wide vegetation zones (Fig. 2). The concurrent works with this, such a construction of the river sluice gate and the catchment basin development, together rapidly aggravated the lake water quality. The lake fishery, which once sported the nation’s highest catches of pond smelt and white bait, was the worst hit: the total catch decreased down to a quarter in Nishiura area and to a tenth in Kitaura area of their heyday figures.
Various government-initiated measures and projects were implemented against the unfolding water pollution and ailing biodiversity in Lake Kasumigaura, which endured environmental devastation due to eco-unconscious development. Although these schemes temporarily relieved the pollution, the water quality again turned downhill and continued the same without any signs of improvement.
There is a widely spreading acknowledgment that a better lake environment requires a coalition of separately conducted projects under a catchment-wide comprehensive strategy. In line with this trend, the government organized a project team consisting of the authorities concerned, although few catchment-wide measures and total watershed management projects have been put to practice thus far. What we needed was a new concept and mechanism that will create a coalition of a wide variety of government agencies and other bodies related to Lake Kasumigaura and its catchment area.
The Asaza Project is a cooperative project launched on the basis of the above recognitions. A non-profit organization free from conventional frameworks coordinates a setting for cooperation to work toward catchment-wide environmental conservation and restoration.
A society coexisting with nature requires a strategy to establish a localized “cyclical society”, where such social systems as industries and education incorporate the dimension of environmental conservation to produce flows of humans, goods, and money, that are conscious of material and water circulation in the ecosystem. Coexistence with nature can only come true when the human and social networks established under this strategy and the ecological network overlap each other.
For this monumental work, grass-roots activities play a vital role by offering a key element for these networks: the bond among the vertically-structured administrative policies and the social spheres to integrate the community from the community member’s point of view.
Since 1995, we have been engaged in the “Asaza Project: Lake Kasumigaura/Kitaura Revival Project through Uniting Lakes, Forests, and People”, a mission based on the above strategy to establish the cyclical society coexisting with nature in the Lake Kasumigaura catchment area.