Shirogane Blue Pond, Hokkaido

A pond in Biei whose water looks uncannily blue among dead larch trunks. Born by accident from volcano defences, it looks completely different each season.

Bright blue water and pale tree trunks of the Shirogane Blue Pond — Photo: Babiesan, CC BY-SA 3.0, via Wikimedia Commons

Standing dead trees reflected in the still water of the Blue Pond, with green forest behind — Photo: pakku, CC BY 3.0, via Wikimedia Commons

A pond created by accident by volcano defences

Shirogane Blue Pond is in the Shirogane area of Biei, a town in the middle of Hokkaido. After Mount Tokachi erupted in December 1988, a check dam (a small dam that holds back earth and rock) was built on the Biei River to protect against volcanic mudflows (disasters in which snow melted by an eruption rushes downhill together with mud and rock). Water collected behind that dam and formed this pond. It was never built as a tourist attraction.

Larch and birch trees that were drowned by the water still stand where they died, and together with the blue surface they create a scene like nowhere else. In 2012 it was used as a wallpaper for Apple's computer operating system "OS X Mountain Lion", which made it known abroad too.

Why is it blue?

According to the Biei Tourist Association, water from the Biei River, which flows below Shirahige Falls in Shirogane Onsen, mixes with water from another stream containing aluminium and other substances, and this creates extremely tiny particles in the water. When sunlight hits them, blue light, which has a short wavelength, is scattered more easily, so the water looks blue to our eyes.

That also means the colour is not always the same. The tourist association notes that in spring when the snow melts, or after heavy rain, the substances are diluted, and the water may turn cloudy or stop looking blue.

Enjoying it through the seasons

Hokkaido's official tourism website describes how it changes through the year: a powerful blue from snowmelt in spring, a clear blue set off by fresh green leaves in summer, a contrast with the autumn colours in autumn, and a white world under snow in winter.

In winter the pond is covered in snow and the blue water cannot be seen, so during that period it is lit up after sunset. The dates and times change from year to year, so check the Biei Tourist Association's official website.

Getting there

From JR Biei Station it takes about 20 minutes by car or by bus (Dohoku Bus), and about 40 minutes by car from Asahikawa Airport. There is a paid car park, and the hours it can be used vary by season. Charges may change, so check the official website for the latest information.

The pond is about 2.5 km north-west of Shirogane Onsen (a hot spring village), so you can combine your visit with a night at the hot springs.

Tips

It gets busy in the afternoon, so the tourist association recommends visiting in the morning.
Going beyond the designated areas is dangerous. Never go into the pond.
The site may be closed in bad weather. If a storm looks likely, check the official information before you set off.
The colour changes with the weather and the state of the water. After rain or during the snowmelt season, be prepared for it not to be as blue as in the photos.