Koshimizu 【古清水】3 The Japanese surnames etymology dictionary.
① Yamanashi-ken Koushuu-shi · Originated from the Oosu village of Kitashitara - mura daigasatos . "Satsu" of the Majin Sato Pass was used. Aichi-ken Nishio-shi I tell him that he came from Yoda - cho in Karasa Town. It was in the Edo period in the same place.