Getting to Takayama 高山市, located in the alps of the Gifu Prefecture 岐阜県, meant the chance to make my first trip on one of Japan's famous Shinkansen 新幹線 bullet trains, followed by a winding journey up through the mountains on a local train.
For my time after Tokyo 東京 I'd planned an itinerary that would cover a few thousand kilometres, so before coming to Japan I purchased a Japan Rail Pass. The pass, available in standard or Green Car versions, grants unlimited usage of the JR network, including reserving seats in advance. I made use of the pass the previous night at Tokyo Station 東京駅 to book my trips for the day ahead, so it was just a matter of showing up.
Dragging my suitcase through the stations and the Yamanote Line 山手線 to Shinagawa Station 品川駅, I waited just a few minutes, taking the photo above, before boarding an N700 series super express Nozomi のぞみ (Wish) on the Tōkaidō Shinkansen 東海道新幹線 from Tokyo 東京 to Nogoya 名古屋.
On the train ride back, the scenery slowly transitioning from natural back to artificial, we chatted more about the city, our countries and more. A change at Ōmiya Station 大宮駅 and then on to the hive of Shinjuku Station 新宿駅 where we eventually parted ways, with Yoshida-san 吉田さん confident that I wouldn't get lost.
As I write this, it's recently become possible to tour other sections of the Metropolitan Area Outer Underground Discharge Channel 首都圏外郭放水路, like the turbine room and the top of the first shaft, although proficiency in Japanese is still a requirement. Perhaps I'll go back some day and check it out again, as the language barrier is less of a problem for me now than it was then: unbeknownst to me at the time, a few months later I'd meet the man who would become my husband, who also happens to speak Japanese. A lot has happened in the past few years.
Back to Shibuya 渋谷 and the hotel for a break, then across to Tokyu Hands 東急ハンズ again for another dig around and a bite to eat for lunch. After, on to the Yamanote Line 山手線 and north a couple of stops to explore more of the skyscraper district of Shinjuku 新宿 on foot. A popular place to visit is the Tokyo Metropolitan Government Building 東京都庁舎, due to the impressive views offered by the observation decks on the 45th floors of both towers, 200 metres up. It's also a gem of a building architecturally, with a look of constructive solid geometry. So that's where I went, and it was totally worth it: from the observation level the vastness of the city becomes apparent, filling everything below the horizon, an ocean of concrete dotted by islands of bushy dark green parkland flecked with white sakura 桜.
Back down at street level and into the station again, this time taking the Chūō Line Rapid 中央線快速 to Ochanomizu Station 御茶ノ水駅 and on to Akihabara Station 秋葉原駅, to find the Electric Town game store called Super Potato スーパーポテト. I'd obliviously walked past it previously, but prepared with a map screenshot it was easier to find this time around. If you played a lot of Atari 2600 and NES growing up, this is the place for you. Multiple levels filled to the door frames with everything to give you a dose of nostalgia and the excitement of seeing all those titles you'd read about as a kid but never got the chance to play. It's fantastic! The top level also has a small arcade, but the single open window is inadequate ventilation for the miasma of cigarette smoke, so I didn't stay up there too long.
After the retro fix it was just a few stops to Tokyo Station 東京駅, so despite the long day I ventured over to look around before looping back to Shibuya 渋谷 for a red meat feast at B & Loin, some more photos (including the above), then packed things up and called it a night. In the morning, I checked out and started the journey to Takayama 高山市.
Wall segments from the 10 metre diameter tunnel that links the river intake shafts across the basin. On the other side of the road, the tops of the outlet gate mechanisms are visible on the bank of the Edo River 江戸川.
Finishing up, we called another taxi and then made our way through the flat patchwork of streets to Minami-sakurai Station 南桜井駅.
Sampling random items from the ubiquitous vending machines in Japan is irresistible to me, particularly when they offer hot drinks, so while we waited on the platform for the next train to Ōmiya Station 大宮駅 I tried my luck with a hot coffee called Kirin FIRE キリン ファイア. I'll admit, the deciding factor was the cool looking little can: a yellow metallic diamond crimped tin with a red flame logo. Naturally, it tasted as watery and lacking in depth as coffee in a can should.
After some additional snaps and discussion of the system we finished our tour of the underground chamber and ascended once more to the light of day. Back across the field to the top level of the main control building for a debrief and survey, then goodbyes with staff and a wander around the facility.
At the side, various items from the tunnelling and construction phase are on display, like this giant cutting head repurposed as a compass rose.
At the far end of the regulating tank are four giant impellers, the largest of their kind in Japan, each powered (via an impressively large gear reducer) by a modified version of an aircraft gas turbine. At full output, even with all of the silencing systems, it must sound unsettling.
The massive drainage shafts take in water via overflow levees from the No. 18 Water Channel 第18号水路 (shaft two), Naka River 中川 and Kuramatsu River 倉松川 (shaft three), Koumatsu River 幸松川 (shaft four) and Otoshifurutone River 大落古利根川 (shaft five), which then flows to the first shaft and into the tank where the pumps regulate the water flow to keep the level within a safe operational range. It's expelled via six subway tube-sized sluiceways into the Edo River 江戸川, making its way into Tokyo Bay 東京湾 and keeping it safely out of the Naka River 中川 and Ayase River 綾瀬川 basin.
The system has proved its effectiveness, consistently saving huge areas from inundation during even the most extreme rain events.
When it isn't going to be active, the tank is cleared of silt and debris using earthmoving equipment lowered through the first shaft. It's an amazing piece of engineering and an impressive experience in person.
Each of the 59 pill-shaped columns weighs about 500 tonnes. In addition to their obvious function of supporting the roof and the 22 metres of ground above, they act as a counter weight against the buoyancy of the cistern in the surrounding groundwater.
It's difficult to appreciate in photos just how huge they are in real life, but to give a sense of scale each column is seven metres long and two metres wide, and an adult standing next to one would be about the same height as the buttressed base.
After an explanation of the system and its construction, we were invited to visit the underground surge tank.
Outside and at the far side of the field, an oblique concrete structure, like a sunken cube, serves as the entrance to the access shaft. A small black and gold plaque at the side listed the dimensions: 177.1 metres long, 78.0 metres wide, 25.4 metres high.
A hundred or so metal stairs down, the temperature steadily falling, then into the middle of the massive, dimly-lit cavern, where an array of giant columns towered, unshakeable.