Etymology and distribution of 寶川.

Takaragawa 【寶川】^{レベル1
Very rare}  The Japanese surnames etymology dictionary.

徳嵩 Tokutake reference.

Houkawa 【寶川】^{レベル1
Very rare}  The Japanese surnames etymology dictionary.

Kanagawa-ken , Toukyou-to , Fukuoka-ken .

① Topography . From the groove in the side. Tell from Yamanashi-ken 's place name. Period, location unknown.

② Fukuoka-ken Midzuma-gun Ooki-machi Origin of Yokomizo. A place name with a record since the Edo period. There is a record in the same place in 1259 (Masayasu first year). It is said that the area is located in the east of Aomori-ken · Northern part of Iwate-ken (Old: Branch County).