This mining pollution not only affected Watarase-gawa River Basin but also spread across the Gyotoku area through Edo-gawa River and across the Kasumigaura area through Tone-gawa River.
なお、この鉱毒被害の範囲は渡良瀬川流域だけにとどまらず、江戸川を経由し行徳方面、利根川を経由し霞ヶ浦方面まで拡大した。