Tachikawa Walk: Nekawa Green Path to the Tama River, a Riverside Guide

A Tachikawa riverside walk: along the Nekawa green path, built over a river buried in 1972, to the Tama River and its winter views of Mount Fuji.

日本語で読む（Japanese version）

The name is written with the characters for “standing” and “river”: Tachikawa (立川). Which river is that? The City of Tachikawa officially states that it does not know.

Few people hear the name Tachikawa and think of water in the first place. Big shopping buildings by the station, the monorail, the lawns of Showa Kinen Park: if anything, this city in the Tama area — the western half of Tokyo, beyond the 23 central wards — has a dry face.

But slide the map south and the city breaks off at the cliff of a river terrace, and below it a narrow green band appears. Go further south still and you hit the broad floodplain of the Tama River. The city’s official materials say that the Tama River flows along the south of the city, and that apart from the green slopes of the Tama River terrace cliff, the land is broadly flat. A city on a flat plateau steps down toward the water only at its southern edge.

It was the bottom of that step I wanted to walk. The Nekawa Ryokudo, the Nekawa green path. Where a river once flowed there is now a green path, and along that green path, water flows. If the river was filled in, where on earth does the water flowing here now come from?

And then there is the matter of the name. This city has had a river in its name from the start. Yet nobody can say which river it is.

The city’s official website confesses the origin of its name quite plainly. The city board of education’s book Place Names of Tachikawa introduces several theories. The tatekawa theory: the Tama River, flowing east to west in front of the provincial government office, was called “the river of the sun’s warp” (hi no tate no kawa). The tagichikawa theory, from the Tama River’s swift rapids. The tachikawa “mansion river” theory, because there was a fortified residence (tachi) at Fusai-ji Temple. And the Tachikawa clan theory, because a family named Tachikawa lived here. To which the city adds: none of these theories has been confirmed, and the truth is not known.

Here is a city that states flatly that it does not know where its own name comes from. I rather like that candour. In which case, the only thing to do is walk and see for myself. Where the water comes from, and which river is in the name. With those two questions, I left the station by the South Exit.

From Tachikawa Station’s South Exit to the Nekawa green path (where the walk begins)

The Nekawa green path is about 15 minutes’ walk from the South Exit of JR Tachikawa Station. From Shibasaki-Taiikukan Station on the Tama Toshi Monorail, the city says, it is about one minute.

The green path is the backbone of a large park called Tachikawa Park. Tachikawa Park is a regional park spanning the districts of Shibasaki-cho and Nishiki-cho; along the axis of the Nekawa green path, about 1.3 kilometres long, a gymnasium, baseball fields and an athletics stadium are dotted around it. It is not the fenced, square plot that the word “park” might bring to mind. It is a long, thin watercourse running along the edge of the city.

The topmost section of the green path begins around the point where the Zanbori River meets the Okutama Bypass, the city’s page says. From there, heading downstream, come a pond with steps down to the water, an arbour jutting out over the water, and a water plaza where children can play safely. The path was built between fiscal 1992 and fiscal 1996, divided into four zones, each with its own theme for the waterside and greenery.

At the same time, the spring water flowing in from the terrace cliff and the avenue of old Somei-Yoshino cherry trees were preserved as they were. What was newly made and what was kept stand side by side along this narrow path. Telling which is new and which is old as you walk is the best way to enjoy it. For someone like me, who is bad at reading maps, there is another blessing. A single path along a stream is impossible to get lost on. The water quietly walks on ahead of you.

North of the Shibasaki Gymnasium, a plaza called “Ganigara Hiroba” opened in April 2017, making use of the greenery and springs of the Tachikawa terrace cliff and the Shibasaki irrigation channel. The name of the plaza has a story behind it — one I will save for the quiz.

A report written by a keen walker who strolled this green path says, of the landscaped channel, “now it looks like nothing but a natural river.” It has been carefully built over 30 years to look exactly like that. So what kind of river was this natural-looking river originally?

The story of a river called the Nekawa

What kind of river was the Nekawa? The city’s walking-course guide tells its history briefly but precisely.

The Nekawa was originally a river that gathered the spring water at the foot of the river terrace. Upstream, the Kyukason irrigation channel from Haijima flowed into it; downstream, at Aoyagi, it fed into the Fuchu irrigation channel; and in Tachikawa too it was used to water farmland. Water seeping out at the foot of the cliff gathered, watered the rice paddies, and was handed on to another channel. Ne means “root,” and the name “root river” suits its character well.

The turning point came in the Meiji era. The Zanbori River, which until then had been made to join the Tamagawa Aqueduct near Sunagawa Ichiban, had become dirty, so around 1908 a new channel was dug, and the Zanbori was made to join the Nekawa at “Taki-no-shita” in Fujimi-cho. A spring-fed river had another river poured into it.

In the Taisho era (1912–1926), the cherry trees that young people had planted on the Nekawa’s banks came into glorious bloom, and people floated boats on the river and enjoyed peaceful days by the water, the city writes. The small spring-fed river grew into a famous cherry blossom spot. The blossom-viewers of those days looked up at the cherries from the river itself. Today, the ones who get close to the water on the green path are the children playing in the water plaza. Small hands scoop up water in place of oars.

But in 1972, as a flood-control measure, the Zanbori River was bent southeast at Shibasaki-cho 4-chome and sent directly into the Tama River. Because of this, the lower Nekawa was filled in.

Why fill it in? The city’s guide does not go into detail, and simply says “because of this.” A river’s life depends on the volume of water flowing in from upstream. Once the Zanbori’s water went straight to the Tama, the lower Nekawa could no longer be a river. All of that is folded into a single short conjunction. The river where young people of the Taisho era planted cherry trees quietly went under the soil in 1972.

The story did not end there. Because people wished to keep the sound of running water, in 1997, as an “Aqua Park Model Project,” a new green path and 1.4 kilometres of near-natural channel were created on top of the former Nekawa. The city’s walking-course guide says 1.7 tonnes of treated wastewater per minute was run through the channel, and fish, insects and birds came to live there.

Make a river again on top of a buried river. Not with spring water, but with water from the city’s daily life, cleaned and set flowing. You cannot get back what you lost in exactly its old form, so you get it back in another form. There is something practical and clear-eyed about the way Tachikawa does this.

But the source of the water changed yet again. According to the city’s parks and green spaces section, because the supply of water for the Nekawa green path’s stream would stop with a project to incorporate the area into a regional sewerage system, construction was carried out from April to the end of October 2023, around the Kiri-no-Hiroba (Mist Plaza), on a water-purification facility that switches the water to a recirculating system. From spring water to Zanbori water, to treated wastewater, and then to a system that circulates the same water. In a little over a hundred years, this slender river has changed the origin of its water three or four times. And still the surface glitters exactly the same.

That half-answers the first question. The water now flowing in the green path is neither spring water nor Zanbori water; it is the same water purified and sent round again. But where did the original spring water go? The clue lies beyond the cherry bank, in the cliff that runs along one side of the path.

The Nekawa cherry bank and the Path of Poems

In spring, the Nekawa green path becomes a path of cherry blossoms. Second on the list of “Tachikawa’s Twelve Green Views,” chosen by the Tachikawa City Greening Promotion Council, is this “Nekawa Cherry Bank.” Its theme is “the original landscape.” Its highlight, the description says, is the magnificent cherry blossom filling the surface of the stream.

The descendants of the cherries planted by those young people of the Taisho era still stretch their branches over the water. The avenue of old Somei-Yoshino trees was left as it was when the green path was built. In spring it is crowded with people, the city writes. One post by someone who visited in cherry season says it was “a famous spot you won’t regret even if you go with sky-high expectations.” Famous spots usually come with a warning: don’t expect too much. Cherry blossoms that come with a guarantee that you can expect too much are rare.

Now, in October, the cherry leaves are changing colour and beginning to fall. Once the bustle of spring has gone, an avenue of cherries shows off the skeleton of its branches. The twists of trunks that have been here for nearly a century catch the eye more in the season of falling leaves than in the season of flowers.

Along the green path, stone monuments stand here and there. This is the Shiika no Michi, the Path of Poems. According to the city’s cultural-properties section, the Path of Poems was created, centred on the Nekawa green path, as part of improving the cultural environment, and stones carved with haiku, tanka and modern poems by writers closely connected with Tachikawa stand along a total of about 2.4 kilometres.

The Tama River appears often in the carved words. The stone of the poet Wakayama Bokusui bears the tanka: “Tamagawa no asaki nagare ni ishi nagete asobeba nururu waga tamoto kana” — “Throwing stones into the shallow flow of the Tama River, playing, how wet my sleeves become.” The stone of Wada Sanran reads: “Shigure ka to to o akete mireba shigure narazu hoshizora saete Tamagawa no oto” — “Thinking it an autumn shower, I opened the door: no shower, but a clear starry sky, and the sound of the Tama River.” The stone of the poet and sculptor Takamura Kotaro carries a poem about green onions sent to him by a friend in Tachikawa. Kotaro called the onions children of the wind that races across the Santama plain, the elite troops of winter. And he went on to write, “Damn it, sculpture is put in the shade.” Here was an onion that made a sculptor admit his own work had lost. Tachikawa’s green onions were strong enough to be carved on a monument.

You open the door thinking you hear rain, and there is a starry sky, and what you were hearing was the river. Reading Sanran’s poem, I imagine how quiet the nights were around here. There was a time when the river sounded so near and so loud you could not tell it from rain. Back then, open your door and you heard the river. Walk the green path today and the sound of the Tama barely reaches you. What lies between is a century’s worth of roofs and roads.

One side of the green path is the cliff of the river terrace known as the Tachikawa gaisen, the Tachikawa terrace cliff line. The Twelve Green Views choose the Tachikawa terrace cliff around the Tokyo Metropolitan Agriculture and Forestry Research Center in Fujimi-cho as their third view, naming as highlights the Musashino woodland that survives on the cliff and the spring water that can be seen from parts of it. The Nekawa was originally a river that gathered the spring water at the foot of this cliff. The cliff and the river are the front and back of a single landform.

Spring water can still be found here and there along the cliff. At the Tachikawa City History and Folklore Museum, which the city’s walking course places near the end of its “Walking the Old Village” route, there is a pond that collects water welling up from the terrace cliff. The land of this museum, opened on 1 December 1985, was part of the residence of Inoue Shigeo, who lived in Fujimi-cho; Inoue, chairman of the city’s cultural-properties protection council, donated it to the city in the hope that a museum would be built there. When they dug the land on which his family had lived for more than 400 years, the remains of a Heian-period settlement, the Dainoshita site, came to light. People lived beside spring water a thousand years ago, too.

The Tokyo Metropolitan Agriculture and Forestry Research Center nearby is also an old-timer on the cliff top. It was founded in 1900 as the Tokyo Prefectural Agricultural Experiment Station in Nakano, and moved to Tachikawa between 1920 and 1924. The cliff the Twelve Green Views chose as the highlight of the Tachikawa terrace line is the one around this research centre.

Sometimes water even climbed the cliff. In 1737, in the Edo period, the Shibasaki branch channel was drawn off the Tamagawa Aqueduct near Matsunaka Bridge. In Shibasaki village on top of the plateau, it was used for drinking water; below the plateau, for the rice paddies; and it also powered a total of 11 waterwheels. At the Fujimi-cho 2-chome crossing, the main channel and the branch were divided in a ratio of seven to three. To supply water to houses that already stood there, the branch read the slight rises and falls of the land, flowing from north to south and in places, the other way, from south to north. Stretches where the branch still flows in an open channel and the old cobblestone banks survive are protected as a city historic site. On a plateau that everyone calls flat, the people of Edo read the tiny undulations and showed the water its way.

The cliff also holds a memory that must not be forgotten. According to the city’s walking course, at Yamanaka-zaka there was an air-raid shelter dug into the terrace cliff. Originally dug to evacuate the city hall’s official documents, it became a refuge for local people as the war intensified. Before dawn on 4 April 1945, a bomb hit it directly, and 42 people sheltering inside were killed. Thirty-two of them were children. Today there is a Jizo hall at Yamanaka-zaka in their memory. The cliff gives birth to water, tried to protect people, and could not protect them all. All of it is etched into this river terrace.

The Nekawa is not the only river made by the cliff’s springs. The city’s walking course starts at JR Nishi-Kunitachi Station and, before the Nekawa green path, stops at the Yagawa Ryokuchi Conservation Area. West of Municipal Daishichi Elementary School in Nishiki-cho 5-chome, there used to be a place called “Idobata” (“by the well”), where spring water gushed out in quantity. That, it is said, was the source of the Yagawa stream. In the land consolidation of the early Showa era (the late 1920s and 1930s), the cobblestone embankments still seen on the Yagawa today were built. As urbanisation advanced, the water vein from Idobata was cut, and the source moved to around Yagawa Benzaiten in Hagoromo-cho 3-chome. Even so, the stream near the source is still clean and rich in plants and insects, the city writes. The Tokyo Metropolitan Government has made the basin the Yagawa Ryokuchi Conservation Area, protecting it as nature left among the waves of urban development.

Cut a water vein and the spring comes out somewhere else. Just as the Nekawa was buried and revived with different water, the Yagawa survived by moving its source. The water below the cliff changes its shape to suit people’s convenience, yet it never disappears.

The same walking course includes a small Inari shrine, Sawa Inari, in Shibasaki-cho 4-chome. Sawa, “marsh,” is an old place name here, and the shrine sits on top of a small mound at the end of a narrow lane between houses. For a long time it has been worshipped as a god of the rice paddies, and even now, on the first Day of the Horse in February, neighbours raise five-coloured banners and make offerings. Judging from its shape, the mound is thought to be a round burial mound (kofun) from around the sixth or seventh century. The god of the paddies sits on a mound that may be a grave from some 1,400 years ago. For an Inari deity, that is a remarkably distinguished pedestal. Water, paddies and prayer are stacked on a single small rise.

In Shibasaki-cho, not far from the green path, is an older Tachikawa. Suwa Shrine, said to have been brought here in 811 from Suwa Taisha in Shinshu (today’s Nagano Prefecture). Fusai-ji Temple (普済寺), founded in 1353, during the era of the Northern and Southern Courts, by the local warrior band, the Tachikawa clan, as their family temple. The city’s walking course presents the area around these temples and shrines as the centre of old Shibasaki village, and the city’s walking map puts the Nekawa green path and Fusai-ji on the same course. Life on top of the cliff, rice paddies below it. To walk the Nekawa green path is also to walk at the feet of that old village.

A wayfarer’s quiz

Where does the name of “Ganigara Hiroba,” the plaza north of the Shibasaki Gymnasium, come from?

• A: There were once lots of crabs (gani) around here, so the area was called “ganigara.”
• B: An old local word meaning “cliff.”
• C: The name of the construction company that built the plaza.

The answer comes near the end of the article, just before “Before you go.” Until then, let’s walk to the end of the green path. At the end, a suspension bridge that is not suspended is waiting.