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Water supply knowledge

Final update date May 30, 2019

Tips of Water Supply (Q)

water supply

Please be careful

Water knowledge

Tips of Water Supply (A)

water supply

"Let's drink tap water deliciously!"

Tap water is delicious with a little ingenuity at home!

  1. Cool the water: Cooling water can reduce "smell" such as chlorine odor.
  2. Boil: You can remove chlorine odor by boiling water for more than 5 minutes.

※Please note that the water after boiling has lost the disinfecting effect of chlorine and cannot be stored for a long time!

"Do you know how chlorine works?"

I don't like the chlorine odor of tap water and the number of people using water purifiers is increasing. Do you know "the function of chlorine"?
There are two types of chlorine agents: oxidation, which oxidizes manganese and iron, and decomposes ammonia nitrogen, and disinfection, which is indispensable for drinking water for customers.
The tap water we use every day contains more than 0.1 mg / L of chlorine and plays a role in killing pathogenic bacteria such as pathogenic Escherichia coli O157.
It's glittering chlorine, but it works importantly.

"When I felt the water had changed,"

The water pressure of the tap is not constant and is constantly changing.
For example, when you use a lot of water at your home, the water pressure drops, and conversely, when there is no one who uses much water, such as at midnight, the water pressure rises, and it changes depending on the usage of the water supply. In addition, water pressure may change after water supply facility update or water cutoff construction to eliminate poor water supply.
In such a case, please adjust with faucets of your home and use water supply well.

"The first water supply in the world,"

The world's oldest water supply known today is the ancient Roman water supply (Apia waterway), which is said to have been built around 312 BC. During the construction for several hundred years, 14 waterways and a total length of 578 km were constructed.
In Japan, it is said that Odawara Hayakawa Josui was made in 1545. In addition, it is said that Kanda Josui was made in 1590 and Tamagawa Josui was made in 1654 to send water to the town of Edo.
By the way, it is a famous story that the modern water supply that sinks and filters water and sends water using iron pipes with pressure began in Yokohama in 1887 (Meiji 20).

"The world's oldest dam,"

According to records and archeological sites, it has been found that it was created in ancient Assiria and Egypt to maintain water and change channels. The oldest dam site that is currently being confirmed is a dam built by King Menes of Egypt around 2900 BC. This is 11m high and 106m long, made of about 100,000 tons of stone, and seems to have obtained drinking water for slaves and livestock working at the stone quarry.
It is thought that dams have been built around the world since ancient times, but most of them have disappeared with the decline of ancient civilization.

Please be careful

"Beware of forgetting to close the faucet!"

How much do you think the amount of "water" leaking from the faucet and the faucet will be in a day?
When converted to a bucket (about 10 liters), the amount of "water" that leaks out is 3 buckets.
In the "water" that leaks the thread, it costs as much as 30 buckets.
Water is indispensable to our lives. I want to use it carefully.

Beware of toilet cleaning

Wash the toilet once after use.
Let's use large and small levers.

Water knowledge

"What is mineral water?"

Mineral water is classified into the following four types according to the guidelines set by the Ministry of Agriculture, Forestry and Fisheries, depending on raw water and treatment methods.

  • Natural Water: Groundwater collected from a specific water source is not treated for anything other than sinking, filtration, and heat sterilization.
  • Natural Mineral Water: Natural water with inorganic salt blended naturally in the basement.
  • Mineral Water: Natural mineral water is used as raw water to artificially adjust minerals.
  • Bottled water: Raw water other than groundwater, such as surface water and tap water, has no limited treatment method.

"Food culture of soft water and hard water"

Japanese food with light taste using bonito and kelp dashi. Because it does not use much oil, it is attracting attention from foreign countries as a healthy food.
The secret of this Japanese dish is actually in the water. Japanese water has a lot of soft water and rice can be cooked and eaten with water, but overseas there is relatively much hard water, and cooking methods such as frying with oil and cooking with soup are used. This is because calcium and magnesium contained in hard water harden the protein and make it worse.
The world's delicious food was also affected by the water situation.
※"Soft water" and "hard water" are divided according to the content of minerals.

"Supplying water is the secret to keeping youth!"

It is said that 60-70% of the body is made of water. This is for adults, which is reduced to more than 80% for babies and about 50% for elderly people.
In other words, water is lost as we get older. Water in the body is divided into intracellular water contained in cells and out-of-cell water such as blood and lymph nodes. Outer cell water does not change.
Therefore, in order to prevent wrinkles and maintain youth and health, it is important to always keep the body from running out of water!

"Why does the surface of the lake look green?"

When wastewater from homes and factories flows into the lake, algae (plankton) increase due to nutrients such as nitrogen and phosphorus contained in the wastewater.
When a lot of algae grow, the water surface turns green, called Aoko, smells water, and prevents water from being cleaned at water purification plants.
Avoid flushing dirty water as much as possible so as not to generate a large amount of algae!

"How much water do people need a day?"

The amount of water we take out of our body as sweat and urine a day is about 3 liters. In order for humans to live, they need 3 liters of water a day.
For these reasons, Water Works Bureau are requesting that "water" be secured with "3 liters per person per day" as a guide in preparation for a disaster.
In the event of a disaster, it will take three days for emergency water supply activities to get on track, so it is safer to have 9 liters of water per person.

"Why do you water in the summer?"

Recently, it has become rarely seen, but in the past it was called watering, and in the afternoon of summer, there were many scenes of watering the garden and the road in front of the house.
In fact, this is the wisdom of old people's lives that makes use of the characteristics of water. When water evaporates, it is called vaporization heat and works to remove heat from the surroundings. In an era without air conditioning, I was trying to make the hot summer afternoon a little cooler.
Why don't we water a little in the wind without relying too much on cooling?

"The forest works to protect water,"

The forest upstream of the river works to store water. In the forest, rainwater that falls on the mountain is taken in the soil as groundwater, and "water" is drained little by little when it does not rain for a long time (when it is drought).
In addition, while the rainwater passes through the thick soil layer, it removes dirt and gives us clean and delicious water containing minerals instead.
In addition, forests are also called "green dams" because they prevent floods and serve as natural dams, which moisturize our lives.

For inquiries about water supply, please contact Water Works Bureau Customer Service Center.

Water Works Bureau Customer Service Center

Telephone: 045-847-6262 Fax: 045-848-4281
※Please be careful not to make a mistake.

Inquiries to this page

Water Works Bureau General Affairs Division, General Affairs Department

Telephone: 045-671-3105

Telephone: 045-671-3105

Fax: 045-212-1155

Email address: [email protected]

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