<figure id="attachment_414967" aria-describedby="caption-attachment-414967" style="width: 2037px" class="wp-caption alignnone"><a href="#" data-ident_hash="1be365f7"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2025/02/383c3a138a95b5de75a37492d425f636-2.jpg" alt=""></a><figcaption id="caption-attachment-414967" class="wp-caption-text">The interior of a water pipe in Osaka City, photographed in &#8217;23. Water stains are sticking to the pipes after years of use.</figcaption></figure>
<h2> Abnormalities in the water supply infrastructure</h2>
<p><span class="strongInContent"> This is the inside of a water pipe that had been in use for around 40 years. It was originally a clean cavity, but a large amount of water stains and impurities have accumulated and corrosion has progressed. If left unattended, this can lead to water leakage and damage, resulting in major accidents.</span></p>
<p> Mr. A, who runs a water pipe maintenance business in Osaka City, confided with a sigh.</p>
<p> On January 28, a road in Yashio City, Saitama Prefecture, suddenly caved in. A 2-ton truck driven by a 74-year-old man fell into the hole, which was about 10 meters in diameter and 5 meters deep. The cause of the cave-in is believed to be a broken sewer pipe and water leakage.</p>
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<p> About two weeks after this accident, water pipes were damaged one after another in Sakai and Mihara wards in Sakai City, Osaka Prefecture. Water was cut off, roads were closed, and other damage occurred. Mr. B, a former employee of the Osaka City Waterworks Bureau, pointed out the damage with a sharp tone of voice: &#8220;The service life of water pipes is 40 to 50 years.</p>
<p><span class="strongInContent"> The service life of a water pipe is said to be 40 to 50 years. Normally, they should be replaced with new ones before their service life is exceeded. But many of Osaka&#8217;s water pipes are left to deteriorate and corrode.&#8221;</span></p>
<p> Mr. B cited the decrease in the &#8220;distance of newly replaced water pipes&#8221; as an indicator that clearly shows the disastrous state of Osaka City.</p>
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<p><span class="strongInContent"> Until about 10 years ago, this pace was maintained. However, in recent years, the pace has dropped to 40 to 60 km. According to the &#8220;Osaka City Waterworks Account Settlement for Fiscal Year Reiwa 2023,&#8221; the total distance of water pipes installed has dropped to about 45 km, nearly half of the original distance. That is how many battered water pipes remain.</span></p>
<p> The distance of the water pipes is not the only indicator of the seriousness of the situation. Mr. A laments, &#8220;The number of construction projects is also decreasing.</p>
<p><span class="strongInContent"> For example, in fiscal 2007, Osaka City placed about 90 orders to private contractors for the installation of water pipes. However, over the past few years, the number has been steadily declining, and in FY 2011, the number was down to 62. There are whispers among contractors and waterworks bureau officials that this is because the budget for the Osaka-Kansai Expo has been taken away. Some contractors are experiencing financial difficulties due to the decrease in the number of construction projects.</span></p>
<div data-friday-nextpage-lead=" Why Has the Total Distance of Waterway Installation Decreased?"></div>
<h2>If a Nankai Trough earthquake were to occur now&#8230;&#8221; Mr. A warned, citing his own disaster experience.</h2>
<p> Mr. A sounded the alarm, citing his own disaster experience.</p>
<p><span class="strongInContent"> In the Great Hanshin-Awaji Earthquake, broken water pipes caused delays in firefighting activities, resulting in extensive damage. We should quickly replace water pipes that have deteriorated over time, as well as those that do not meet earthquake resistance standards. If a Nankai Trough earthquake were to occur now, firefighting would not be able to take place properly and Osaka would become a sea of fire. &#8230;&#8230;&#8221;</span></p>
<p> Why has the total distance of water pipes installed been decreasing? The Engineering Department of the Osaka Municipal Waterworks Bureau responded, &#8220;The most common reason is the aging of the pipes.</p>
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<p><span class="strongInContent"> We are giving top priority to the elimination of the &#8220;ordinary and high-grade cast iron pipes,&#8221; which are the most aged and have suffered a very high rate of damage in past earthquakes. In particular, we are working to increase the pace of renewal of large-diameter backbone pipelines. For distribution branch pipes with smaller diameters, we have calculated the future renewal demand based on the usable years of the pipes based on the results of past surveys, and have set the immediate renewal pace at an average of approximately 45 km per year.</span><br>
<span class="strongInContent"> In the future, we plan to renew a total of approximately 53 km of pipelines per year on average.</span></p>
<p> Mr. A, however, refuted the plan, saying, &#8220;Fifty-three kilometers is not enough at all.</p>
<p> Yoshiharu Yokoyama, director of the Daichi Disaster Risk Research Institute, points out that, &#8220;The Yashio line, where the cave-in accident occurred, is a major roadway in the city.</p>
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<p><span class="strongInContent"> Yashio City, where the sinking accident occurred, is located in an area with soft ground. When the ground is weak, sewer pipe breakage causes soil and sand to flow into the water pipes, creating a cavity under the road. As a result, it is believed that the road could not withstand the weight and vibration of cars and other vehicles, causing it to cave in. Osaka Prefecture has a lot of reclaimed land, and because the sea used to extend inland, the ground is soft in many areas. The Expo site is also reclaimed land. Osaka must be even more prepared than other prefectures for the risk of aging water pipes.&#8221;</span></p>
<p> How will Mayor Hideyuki Yokoyama (43) and Governor Hirofumi Yoshimura (49) listen to the urgent warnings from the field?</p>
<figure id="attachment_414966" aria-describedby="caption-attachment-414966" style="width: 2332px" class="wp-caption alignnone"><a href="#" data-ident_hash="60880b90"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2025/02/703a2a74fd0f460b5e8f6230ece58be0.jpg" alt=""></a><figcaption id="caption-attachment-414966" class="wp-caption-text"> The scene of a cave-in accident in Yashio City, Saitama Prefecture. Some say it will take two to three years to fully restore water pipes and roads.</figcaption></figure>
<figure id="attachment_414968" aria-describedby="caption-attachment-414968" style="width: 1546px" class="wp-caption alignnone"><a href="#" data-ident_hash="45999330"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2025/02/1271a895daf7b24007e40cada488fcf3-2.jpg" alt=""></a><figcaption id="caption-attachment-414968" class="wp-caption-text"> Mr. A, interviewed by FRIDAY, said that when water pipes corrode, as in the first photo, muddy water can flow into homes.</figcaption></figure>
<p> From the March 7, 2025 issue of FRIDAY</p>


 Kyodo News (2nd photo) Kei Kato (3rd photo)

 A road cave-in in Saitama Prefecture was reportedly caused by a broken sewer pipe and water leakage. About two weeks after the accident, a series of water pipes were damaged in Osaka, causing water outages and other damage. An official in the water industry in Osaka City revealed the devastation in the city.

 The road cave-in in Yashio City, Saitama Prefecture, could have happened anywhere--and it's not the first time it's happened.

Water Supplier Warns: &#8220;Water Pipes with Advanced Corrosion Are Still Left Unattended&#8221; &#8211; Astonishing Internal Photographs to be Released

Water Supplier Warns: “Water Pipes with Advanced Corrosion Are Still Left Unattended” – Astonishing Internal Photographs to be Released

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