The Building of a Nation: Historical Civic Works in Osaka (Travel)
Historical sites in Japan aren’t all mist-shrouded castle ruins and cobblestone avenues lined with paper lanterns. Between the shogunate’s two centuries of isolationism and the post-war/pre-Bubble glitz lies the Meiji period, a hectic helter-skelter of modernization that spanned the 44 years following the fall of the Tokugawas. This is when Japan pulled out all stops to “catch up” with the Western world economically, industrially, and socially. When the public purses allowed (and sometimes when they didn’t), massive projects and far-reaching legal reforms were the orders of the day.
For those with an interest in the history of engineering, there is one example of the former that still remains in shockingly good condition up in the sleepy residential section at the northern tip of Osaka’s economic and business heartland, Kita Ward. Registered as a National Cultural Treasure in 2008, the site is called the Old Keba Weir and Number 1 Keba Lock, or simply the Keba Lock for short. First, let’s take a look at the background.
Located along a peaceful, grassy stretch of the south banks of the Yodo River, the park-like atmosphere surrounding the 100-meter brick-and-concrete lock belies the wide-scale engineering efforts that went into creating the current landscape. Called the Seta or the Uji as you travel further upstream toward its source at Lake Biwa, the Yodo was the dominant waterway for the people of old Osaka, not just for watering crops but for trade, as well. It was the artery connecting Osaka with Kyoto, and the landscape of the river was dominated by a type of slender vessel called a sanjikkoku-bune (thirty-koku boat, a koku being an old measure for rice of about 150 kg or 280 liters). Yet, disaster struck in the form of repeated flooding, which both brought ruin to rice paddy farmers along the river and famously filled Osaka Bay with silt in the early Meiji era.
This is where Hyogo-born grandfather of waterway civic engineering Tadao Okino stepped in. There had been an attempt in the recent past to merge the bulk of the winding, flood-prone southern branch of the Yodo River (the Oo) into the northerly branch of the Nakatsu River, but it was Okino who saw the project through to completion. Over a 14-year period of construction from 1896 to 1910, the torrents of the Yodo River were shifted to a near-straight shot path along the bed of the Nakatsu, changing the landscape enormously and turning the southern Oo River into a far more tractable waterway.
However, things are hardly ever so simple when topography is involved. The rerouting of the river caused a difference in height of more than a meter between the waters of the new Yodo River and the Oo River, which was still an important waterway for commerce. Okino and co.s’ s engineering again came to save the day, this time in the form of the Keba Lock, completed in 1907. Let’s take a look at the construction of this historical feat of engineering, piece by piece.
When you arrive at the site, the lock itself will be hidden from view. You’ll first pass under the meganebashi, coming around to the Oo River-side set of gates.
The lock used a pair of miter gates, a technology invented by Leonardo da Vinci and named after the joined fabric of a bishop’s mitre.
Though miter gates require a stout construction to stand against water pressure, they don’t require any mechanisms whatsoever above the gate, which would otherwise limit the height of vessel passing through.
Mooring rings were set at intervals along both sides of the chamber. These rings held boats in place while the water level was raised and lowered, allowing vessels to pass between the two rivers.
Walking along the mooring chain to the staircase to the base of the Yodo River-side gates, you can appreciate how even a meter’s difference in water levels can present a huge hurdle for maritime activity.
The movement of ships wasn’t the only challenge these Meiji-era terraformers had to face. Silt accumulation would still be a problem around the newly-created junction, and the Oo River would require regular adjustment for flow volume. To address both these issues, construction began in 1904 on a type of flow-control facility called a “dredge weir,” which would allow both easy silt removal as well as water flow adjustments on the Oo through the insertion and removal of large pieces of timber.
The weir was finished up in 1910. However, even as these facilities were under construction, time marched on and technology was changing, and in that same year, the Keihan Electric Railway had its inaugural run between Osaka and Kyoto, coming to largely replace cargo traffic along the Yodo River. Still, operations continued for over six decades. In January 1976, the nearby Keba took over for Keba Number 1 Lock. At that time, the weir’s duty had already been taken up by a modern sluice facility over a year before.
Luckily for the historically-inclined visitor, these civic works of the early 20th century remain in a well-tended condition. To get there, leave Exit 2 of Tenjimbashisuji 6-chome Station on the Tanimachi/Sakaisuji subway lines and turn left to head north away from Miyakojima Dori. It’s about a 10 to 15 minute walk straight along this road to the levee. You’ll find the entrance about 100 meters east (right) of the T-section at the levee that ends your journey north. Alternatively, just put “3-3-25 Nagarahigashi, Kita Ward, Osaka” into your map application and let your GPS do the walking.
Bonus for the Buddhism-inclined
On the river side of the lock across from the meganebashi, you’ll find a copse of trees and a small hill where a stone staircase leading up to a memorial stone commemorating the completion of the lock and weir. However, just nearby is an unassuming looking open-faced wooden hut housing three statues. Weathered over countless centuries, these stone sculptures are actually Jizo statues excavated or dredged up during various construction projects in the area, including the lock and weir construction. Though the statement is of doubtful historicity, legend holds that these are three of the 60,000+ Jizo statues created during the semi-legendary reign of Prince Shotoku in the 6th and 7th century as part of his promulgation of Buddhism.