Water Report (1997)

Our biggest river, the Fuefuki-gawa is in the Kofu Basin. In May of 1997, the Fuefuki tested at pH 7.0.   In Summer, the alkalinity increased significantly.  In June, it was pH7.5; and in July it was 8.0.  By September, the alkalinity dropped to pH7.8.  We hypothesized that the increased alkalinity was resulting from runoff from nearby farmland.   Tests in tributary rivers in Nakamichi seem to confirm our hypothesis.  At a source low in the valley, the Makadou-gawa river tested at pH 8.0 in June and pH 7.5 in July.  In contrast, a river in the mountains of Nakamichi-Minami tested at pH 7.0 (July).

The degree of particulate matter, or (COD), in July for the Fuefuki and Makadou rivers [7mgO/l (ppm)] was higher than the TAKIDOU river [2mgO/l (ppm)] in the mountains of Nakamichi-minami. If the clear-cut timber-cutting methods petroleum-based agriculture used in this area continue, erosion could contribute toward higher (COD) levels in the near future.

A high alkalai stream in Toyotomi-mura (July 1997)

Kofu-Basin Map | Fuefuki River Map
Nakamichi-cho Toyotomi-mura streams map
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