Omuta (Former Mitsui Miike Coal Mine) about 60 years ago and today

History of Omuta (Former Mitsui Miike Coal Mine)

The city area of the City of Omuta, Fukuoka Prefecture, lies on land that slopes gently down to the Ariake Sea. Only two past aerial photographs can be opened at this location, 1961-69 and 1974-78, and the rest is today's photograph. Even if you switch through the three in order, the trunk road running diagonally and the finely divided blocks hardly move. Only the eastern edge and the western water's edge of the frame move, and you can read that the framework built for coal remains even after mining stopped.

Low land above the coal

The Miike coal seams are shallow on land and become deeper toward the offshore Ariake Sea. In the Edo period the local domain opened pits and mined them, in the Meiji era they became a government-run mine, and in the middle of the Meiji era they were sold to Mitsui. When machines that pumped up water from deep places came in, the tunnels extended under the sea, and a means of shipping out to match the amount dug out became necessary. A dedicated railway carrying coal to the loading place was laid, and in 1908 Miike Port was opened. The convenience of how to connect the pit mouths, the coal-preparation sites, the railway and the port largely determined the direction of this city's roads and tracks.

Facilities in two eras

The 1961-69 photograph is black and white, with fine grain, so that even individual roofs can be counted. In the northwest corner of the frame, buildings of a different size from the rows of houses are placed together, and the boundaries of the site are cut in straight lines. Just south of it a wide waterway crosses diagonally from northeast to southwest and opens into a wide water surface at the left edge of the frame. Several long, narrow ships are moored on the water, and the shore is held by straight walls. From the center to the lower left, fine roofs are packed without gaps, and two wide roads overlap diagonally on top of streets close to a grid.

The right side of the same photograph has a texture different from the city area. Large buildings are placed with space between them, many tracks are tangled among them, and several flat surfaces sunk darker than their surroundings are wedged in. Above the middle of the frame the tracks gather in one place, several long, large roofs line up, and from there sidings open south like a fan. In the lower left corner the city area breaks off, and a smooth, bright surface continues inside a straight boundary. In the lower middle a round structure and an elliptical ring surrounding it appear. In a photograph filled with straight lines and grids, this corner is the only place where curves come out together.

In 1974-78 color is added. The group of buildings in the northwest is filled with reddish-brown and orange roofs, and the water of the waterway looks cloudy brown. The wide water surface at the left edge sinks dark, and to its south grayish-white bare ground and a greenish water surface lie next to each other. On the right side several white cylindrical tanks stand together, and bright surfaces of exposed soil spread together on the slope. The station yard extends long and narrow, with many parallel lines drawn. The shape of the city area is almost unchanged from the previous era, and only the facility side has been worked on.

There are only about ten years between the two eras. Even so, if you line them up with the previous era, the spread of bare ground on the right side and the color of the water at the left edge look like different things. If the amount dug changes, the places for storing and the places for dumping change shape as well. Because the rows of houses do not move, it is easy to find that the places that changed gather at the edges of the frame.

Until the pit mouths closed

Around 1960, a labor dispute in which labor and management were in conflict for a long time took place and drew national attention. In 1963 coal dust exploded in a pit in the western part of the city, a major accident in which many people died. As fuel shifted from coal to oil, the pits finished their roles one by one. Then in 1997 the Miike Coal Mine closed, and mining that had continued for a long time counting from the Edo period stopped. In 2015 the Miyanohara Pit, Miike Port and other sites were inscribed as World Cultural Heritage, as components of the "Sites of Japan's Meiji Industrial Revolution". As an industrial area of the prefecture that prospered on coal and iron, there is also the example of Higashida, where the grounds of a steelworks were rearranged into a town.

What remained and the value of the land

In today's photograph, the cloudy water surface and the grayish-white bare ground from the left edge toward the southwest have disappeared, and surfaces of turf and several sports grounds with circles of soil line up. On the right side of the frame, in place of the tangled tracks and dark surfaces, buildings with large white roofs and wide paved surfaces are placed, with groves of trees between them. The bundle of parallel lines in the station yard has become thinner. The waterway has straight, well-ordered seawall lines, and the color of the water has also settled. The group of buildings in the northwest remains with its roofs changed to white, and in the stadium in the lower middle the elliptical running track is painted blue. The green along the streets has also become more noticeable than in the two past eras.

The height of the land is 2.2 m on the north side, the lowest, and 4.7 m on the east side, the highest, a difference of only 2.5 m. The center is 3.7 m, the south 4.1 m and the west 2.9 m, and nowhere reaches 5 m. It is land with only a slope toward the sea, slightly higher in the east and south and falling to the north and west. The flooding assumptions appear as maps on the city's official hazard map. Because this is a property that cannot be understood from the flatness of the photographs alone, it is worth opening that too.

From the side of land prices, a survey point placed in a residential area of Shinchi-machi is 598 m away. The official land price (Chika Koji) did not move from 1995 to 1998 at 61,500 yen per square meter, and from 1999 it lost value every year. The 31,600 yen of 2022 and 2023 is the lowest value in the records up to the 2026 publication. In the 2026 publication it is 32,700 yen, a slight recovery from the bottom. A series of thirty years spanning the closing of the mine shows, from the side of numbers, how the center of gravity of the city has moved.

Even when the lines and surfaces for carrying coal disappear, the roads and blocks drawn to fit them remain. The traces remain in the direction of the roads: that is the answer that comes out of these three photographs. If you go back and forth between the two eras and today, you can see that the things that disappeared and the things that remained are neatly divided between the edges and the center of the frame.