民衆のために生きた土木技術者たち

青山士は単身渡米し、技術者としてパナマ運河開削工事に携わり、この期間中ガツン
閘門の設計などを担当した。
測量に夢中で汽車の近づくのにも気づかず、間一髪で逃げ延びたこと、
人種差別やマラリヤに悩まされたことなどもあり、二年半に及び測量生活には、
語り尽くせないものがあったようだ。
アメリカにおける外国人排斥運動の影響もあり、パナマ運河の完成を見ることなく帰国。帰国した青山は、廣井の紹介で内務省に技師として入り、荒川放水路の工事に携わることとなる。
荒川放水路の工事は、日本でも初期の本格的機械化土木工事でもあった。
着工から14年の歳月を費やした荒川放水路に水が流された。

宮本武之輔は青山とともに大河津分水可動堰を建設して越後平野の農民を塗炭の苦しみから救った。
信濃川補修工事として施工していた「可動堰」は完成目前となっていたが、長野県を
襲った集中豪雨は、信濃川の水位を急激に上昇させ、分水路付近でも仮締切りを越えん
ばかりに増え続けた。 
現場を預かる宮本は、仮締切りを切って信濃川の濁流を日本海に導くか、
下流域の市町村が洪水に見舞われるのを覚悟で仮締め切りを切らないか、ぎりぎりの
決断に迫られた。
宮本は、「土木屋としてのおれの任務は、人々の暮らしを豊かにすることなのだ。」
と、工事が大きく遅れることを知りながら、
仮締切りを切り、人々を洪水の危機から救った。彼が大河津分水で奮闘したのが1927 
年から31年まで。

八田與一は５６歳で亡くなるまでほぼ全生涯を台湾に住み、台湾のために尽くした。
烏山頭ダムは、台湾西部の嘉南平野の東方の山地にある。渓流をせき止めた堰堤は
１６００メートル以上ある。
セミ・ハイドロリックフィルという、石や土を組み合わせてコンクリート以上の強度を
生み出す石積み工法を用いた。
嘉南平野は台湾最大の平原である。平原を流れる河川が少なく、しかも急流だった
ため、水利としてほとんど機能してこなかった。
このため２０世紀になるまで嘉南平野はサトウキビすら育たなかったといわれる。
この嘉南平野は八田與一が建設したダムと１万６０００キロにおよぶ網の目のような
用水路のおかげで台湾最大の穀倉地に変わった。
地元の人々がこの功績を讃えて八田與一の銅像を建てた。

Engineering works engineers who live for the people

Akira Aoyama visited America all alone, was involved in the Panamanian canal 
excavation construction
as the engineer, and took charge of the design of Gatsn gate etc. for this period.
The train was not noticed even to approach the measurement frantically, and 
it escaped safely in the place in which no horsefly.
There were what etc. were annoyed by the racial discrimination and malaria, 
too and it talked and seems to have been something
that it was not possible to carry it out in the reaching measurement life in 
two and a half years.
The foreigner boycott movement in the United States influences, and it returns
home without seeing the completion of Panaman Canal.
Aoyama who returns home becomes entering in Home office as the engineer on 
the introduction of Hiroi, and involved in the construction of the Arakawa 
tailrace.
The construction of the Arakawa tailrace was an initial real mechanization 
earthwork also in Japan.
Water was poured in the Arakawa tailrace where years of 14 years had been 
spent from starting constructing.

Core of Takenosuke Miyamoto assistant constructed the Okouzu watershed movable weir
with Aoyama and saved the farmer in Echigo plains from the greatest misery.
The water level of the Shinano river was rapidly raised, and localized torrential rain 
that overcame Nagano Prefecture was about to be exceeded a temporary deadline and 
kept increasing also in the vicinity of the spillway though was the finished near future 
"Movable weir"
constructed as Shinano river repair construction.
Does Miyamoto who keeps the site cut a temporary deadline and lead the muddy 
stream in the Shinano river to the Sea of Japan?
A temporary deadline was not cut by the resolution or cities, towns, and 
villages in thedownstream region were urged to suffer from the flood by a very limit decision.
Miyamoto cut a temporary deadline while knowing construction was greatly 
delayed, and saved people from the crisis of the flood ,
saying that "My duty as the engineering works shop is to enrich people's livings". 
It is from 1927 to 1931 years that he strove by the Okouzu watershed.

Yichi Hatta lived almost in Taiwan, and carried out the entirety of one's 
life until dying at the age of 56 for Taiwan.
The Usantou dam is in the mountainous district in the east of Knan field in 
the Taiwanese west. There are 1600-meter or more dam where the mountain stream 
was dammed up.
The stone volume industrial method that combined the stone and the soil 
named semi-Haidororiccfil and invented strength more than concrete was used.
kanan field is the greatest plain in Taiwan. The river that flowed in the 
plain was few and it had hardly functioned as a water supply because it was 
a rapid stream.
Therefore, Kanan field is said to in the 20th century that even sugarcane 
did not grow up. This Kanan field changed into the greatest granary ground in 
Taiwan thanks to the millrace like eyes of the net that reached the dam and 
16,000 kilos that Hatta 1 had constructed.
People in local praised this distinguished services and the bronze statue of 
Yoichi Hatta was built. 



今回の講義では、人民救済に生涯を捧げた青山士、宮本武之輔、八田與一の三人の
土木技術者について学んだ。
青山士はパナマ運河建設にかかわった唯一の日本人である。パナマ運河は3組の水門と
3つの人造湖をつないだ全長約80kmの大西洋と太平洋を結ぶ世界的に有用な運河であり、
その建設には莫大な費用と時間を要した。青山はパナマ運河に７年半勤めた。
最初はポール持ちだったが、彼が非常に優秀で熱意があることが認められ、次第に
アメリカ人並みの待遇を受けるようになった。最後には最も重要なガツン閘門のダムの
設計に携わった。
帰国後、洪水や氾濫で人々を苦しめてきた荒川に全長22kmの放水路を掘り、岩淵水門を
築いた。また、自在堰の陥没により機能が停止していた信濃川大河津分水路の改修工事
に従事した。そのときの工事主任が宮本武之輔である。
　宮本武之輔は、越後平野を度重なる洪水から守るために大河津と日本海の間に放水路
を建設し、竣工から70年経った今でも稼動している稼動堰の設計も行っています。
可動堰が完成目前となっていた昭和５年（1930年）８月、集中豪雨が信濃川の水位を
急激に上昇させ、分水路付近でも仮締切りを越えんばかりに増え続けた。現場を預かる
宮本は、仮締切りを切って信濃川の濁流を日本海に導くか、下流域の市町村が洪水
に見舞われるのを覚悟で仮締め切りを切らないか、ぎりぎりの決断に迫られた。宮本
は、「土木屋としてのおれの任務は、人々の暮らしを豊かにすることなのだ。」
と、工事が大きく遅れることを知りながら、仮締切りを切り、人々を洪水の危機から
救った。また、彼は鉄筋コンクリートに関する権威で、多くの論文を発表している。
　八田與一は、大学卒業後すぐに台湾に渡り、台湾の発展に貢献した技術者です。
八田は嘉南平原の農業灌漑を目的として烏山頭ダムを建設し、水路を張り巡らせた。
八田は単にダムを作っただけではなく、土木作業員の労働環境を適切なものにして、
危険な現場にも進んで足を踏み入れ、事故の慰霊において日本人も台湾人も分け隔
てなく行っている。そのようなことから八田與一は、台湾の人々から今でも感謝されて
いる。
　この三人の共通点は、廣井勇から土木技術者としての精神を学んでいることである。
三人の民衆のための血の通った土木技術は、これからも受け継がれていく。

I studied it by this lecture about three engineering works engineers of Akira 
Aoyama, Takenosuke Miyamoto and Yoichi Hatta who gave a life to people relief. 
Akira Aoyama is the only Japanese concerned with the Panama Canal's 
construction. Panama Canal connects three sets of water gates and three 
man-made lakes, and it is about 80km full length. It was a canal useful 
worldwide which linked the Pacific to the Atlantic and needed great expense 
and time for the construction. Aoyama worked at Panama Canal for 7 years and 
six month. First, he worked as a pole carrier, but he was very excellent, and 
that there was enthusiasm was recognized and received working conditions 
gradually same as an American. Finally he was engaged in the design of the 
most important Gatun Locks. After return home, he dug a flood control channel 
of full length 22km in Arakawa that tormented people with a flood and the 
flooding and built the Iwabuchi water gate. In addition, he engaged in the 
repair work of the Oukoudu waterway　in Shinano river that a function 
stopped for the cave-in of the free dam. Chief construction at that time is 
Takenosuke Miyamoto.
 Takenosuke Miyamoto built the flood control channel between Oukoudu and Sea 
of Japan to protect an Echigo plain from a repeated flood. And he designed 
the operation dam which still operated which passed from the completion in 70. 
In August, 1930 when a movable dam was completion close at hand, 
concentrated downpour suddenly raised the water level of the Shinano River, 
and a muddy stream seemed to go over the temporary dam. Miyamoto who 
supervised the spot had to choose 1 among two choices. One choice disturbed a 
temporary dam, and leading the muddy stream of the Shinano River to the 
Sea of Japan, another choice were not to break a temporary dam at the risk of 
the cities, towns and villages on the down stream undergoing a flood. As 
for Miyamoto, "my duty as the civil engineer is to do the living of people 
wealthily". And he broke a temporary dam while knowing that construction was 
late greatly and saved people from the crisis of the flood. In addition, he 
is an authority on the steel reinforced concrete, and announces many articles.
Yoichi Hatta goes over to Taiwan after graduation from university immediately,
and he is the engineer who contributed to Taiwanese development. Hatta 
built the Usantou dam for agriculture irrigation in Kanan plain and set up a 
waterway. Hatta did not make merely dam. He did the labor circumstances of 
the worker adequately and went to the dangerous spot by oneself. And he 
engraved a name without a Taiwanese and Japanese discrimination into the 
memorial service monument of the accident.
 Their common point is to learn mind as the engineering works engineer from 
Isami　Hiroi. The humane engineering works technology for the people is 
inherited from now on.