The Kamiyama Residence Water Tank

Just west of the gate in the coral wall, facing the road that runs in front of the Kamiyama compound on Kuroshima, stands a small block of reinforced concrete. It measures 1.5 meters east to west, 2.4 meters north to south, and 1.75 meters tall. This is a water tank, built in 1938, and it answers a question every household on this coral island had to solve: where to keep fresh water when the ground gives up so little of it.

The solution was to catch the rain. Water running off the main house roof was channeled into the tank through bamboo gutters, and a filtration tank was set on the north end of its flat concrete roof. Rain became drinking and washing water by way of a simple, deliberate system, with the cistern as its reservoir.

A dated record in concrete

On the east face of the tank, an inscription reads that it was built in the sixth month, by the old lunar calendar, of Shōwa 13, which is 1938. That carved date makes the structure unusually easy to place in time, and it marks a moment when reinforced concrete was reaching even the small outer islands of the Yaeyama group.

The tank entered Japan's register of Tangible Cultural Properties in May 2007 under number 47-0033, recognized for its contribution to the historic landscape. It is the most modern of the four registered parts of the compound, and in some ways the most telling. The earlier well reached down for groundwater; three decades later this concrete cistern reached up to the roof and the sky. The two together trace how an island family kept water within arm's length across the first half of the twentieth century.

What to look for

From the lane the tank reads as a plain concrete box, low and square, presenting its south face to the road. Look for the filtration tank riding on the north end of the flat roof, and for the carved date on the east side. If you can follow the line of the gutters back toward the main house, you will see the whole catchment at a glance: roof, channel, filter, and reservoir, each part doing one job.

The water tank belongs to a single registered compound that also holds the coral perimeter wall, the 1912 main house, and the stone well at the southwest corner. Read on its own, it is a modest utility structure. Read alongside the others, it completes a clear account of survival on a dry coral island. The Kamiyama residence is a private home, so please view the tank from the public lane and leave the compound to its residents.

📍 Plan Your Visit to Okinawa
Find tours, activities & transport passes near Kamiyama Family Home Water Tank
[ Churaumi Aquarium & Shuri Castle Okinawa Tours ]

Q&A

QWhat was the tank for?
AIt stored fresh water on an island where groundwater was scarce, holding rain caught from the main house roof.
QHow did the rainwater system work?
ARunoff from the main house roof was led to the tank through bamboo gutters, passing through a filtration tank set on the north end of the flat roof.
QHow do we know its exact age?
AAn inscription on the east face dates it to the sixth lunar month of Shōwa 13, that is 1938.
QHow is it different from the well?
AThe 1909 well drew on groundwater, while this 1938 concrete cistern stored rainwater from the roof. Both were ways the same household secured water.
QWhen was it registered?
AIn May 2007, as a Registered Tangible Cultural Property, number 47-0033, for its place in the historic landscape.

Basic Information

NameKamiyama Residence Water Tank (Kamiyamake Jūtaku Mizu Tanku)
Location1522 Kuroshima, Taketomi, Yaeyama District, Okinawa
CategoryRegistered Tangible Cultural Property (building), registration no. 47-0033
Registered15 May 2007 (gazetted 29 May 2007)
Date of building1938 (Shōwa 13)
FormOne unit; reinforced concrete cistern, 1.5 m (E-W) by 2.4 m (N-S), height 1.75 m, with a filtration tank on the flat roof; surface area about 3.6 sq m
AccessFerry from Ishigaki Port to Kuroshima (about 25 to 30 min), then bicycle to the Higashisuji settlement
ViewingPrivate residence; the tank faces the road and is visible from the public lane

References

Agency for Cultural Affairs, National Cultural Properties Database: Kamiyama Residence Water Tank
https://kunishitei.bunka.go.jp/bsys/maindetails/101/00006121
Taketomi Town Tourism Association: Cultural Properties
https://painusima.com/cultural/

Last verified: 2026.06.25