Nagamizu 【長水】3 The Japanese surnames etymology dictionary.
① Gifu-ken Kaidzu-shi Haibara originated from Kaizu Town. A place name with a record since the Azuchi-Momoyama period. It was in the Sengoku period in the same place. It was in the Muromachi period in the southern part of Gifu-ken (formerly Mino country). In the vicinity of Yamanashi-ken Yamanashi-shi (formerly Yamanashi-gun), tell the fact that it was also described as "Higara" in the southern part of Gifu-ken (Old: Mino country). Yamanashi-ken Yamanashi-shi Otaki of Mitomi Kamakuchi The shrine of Naga-ku Shrine has a transmission with Mr. Fujiwara's descendant. Fujiwara has "Hara". 藤原 reference.
② Toukyou-to Nishitama-gun Hinohara (Hinohara) village origin. Place name with a record as "Hino original" in the Muromachi period. Tradition at Yamanashi-ken . There is a transmission that it was also called "Hino Hara" in the same place. 日野原 reference.