This natural spring is located on the east side of Mt. Yashio, where its steep slope changes to a gentle slope. While valleys lie on the north and west sides of Mt. Yashio, there is a fault on the eastern edge, allowing rain and melted snow to seep into the ground more easily than on the north and west sides. It is thought that as much as 900 tons of water gush out from this spring per day.

This spring water has a temperature of about 9 ℃, a hardness of 19.0 mg/L, and a pH of 6.9. It is used as tap water in the area, and the local beer “Botsumeki Beer” is also produced using this water.

There are multiple theories about the origin of the name “Botsumeki.” One theory is that the word comes from the Akita dialect “botsu botsu megu,” meaning water gushing out. Another theory is that it comes from “bubbling” in the Ainu language.