Information on sanitary management of water receiving tanks

Water supply refers to the whole facility that supplies water as water suitable for human drinking by conduits and other structures.
Depending on conditions such as the supply target of tap water, it is classified into a water supply business / simple water supply business, a dedicated water supply, a simple dedicated water supply, a small water receiving tank water supply / drinking well, etc.
(Reference) Article 3, Paragraph 1 of the Water Supply Act
In this Act, "water supply" refers to the entire facility that supplies water as water suitable for human drinking by conduits and other structures. However, this excludes temporary facilities.

Dedicated water supply refers to a water supply that supplies water to more than 101 residents or a water supply whose daily maximum water supply exceeds 20 cubic meters, and falls under any of the following.
１．Supply only water (well water, etc.) from its own water source
２．Water supplied by mixing water from its own water source and water supplied from other water sources (such as City of Yokohama, Water Works Bureau water supply).
３．Only water supplied from other water supplys is used as a water source, and falls under any of the following
Oh, total effective capacity of aquarium more than 100 cubic meters
B. The total length of a conduit with a diameter of 25 mm or more exceeds 1,500 meters
(However, the capacity and extension of tanks and conduits that are high enough not to be affected by contamination from the ground surface are not included.)
Dedicated water supply is required to appoint a water supply technology manager and monthly water quality inspections.

(Sidentified laws and regulations)
Article 3, Paragraph 6 of the Water Supply Act
In this law, "dedicated water supply" refers to water supply other than private water supply and other water supply used for water supply business in dormitories, company houses, nursing homes, etc., and falls under any of the following items. . Provided, however, that only water supplied from other waterworks is used as a water source, and that the scale of the water supply facilities underground or on the surface is below the standard specified by a Cabinet Order is excluded.
　(1)　It supplies more than 100 people with water necessary for their residence.
　(2)　The maximum daily water supply of the water supply facility (meaning the maximum amount of water that can be supplied per day.) The same shall apply hereinafter. ) Which exceeds the standards specified by a Cabinet Order

Article 1 of the Water Supply Law Enforcement Order
The standards specified by a Cabinet Order prescribed in the proviso of Article 3, Paragraph 6 of the Water Supply Act (hereinafter referred to as the "Law") shall be as follows.
　(1)　1,500 meters in length of conduits with a diameter of 25 mm or more
　(2)　A total of 100 cubic meters of effective capacity of the aquarium
(2) The standards specified by a Cabinet Order prescribed in Article 3, Paragraph 6, Item 2 of the Act shall be that the amount of water used for drinking by humans or other purposes specified by the Ordinance of the Ministry of Land, Infrastructure, Transport and Tourism is 20 cubic meters.

Article 1 of the Water Supply Law Enforcement Regulations
Water Supply Law Enforcement Ordinance (Government Ordinance No. 336 of 1957). The purpose specified by the Ordinance of the Ministry of Land, Infrastructure, Transport and Tourism prescribed in Article 1, Paragraph 2 shall be used for drinking, cooking, bathing, and other human life.

Please refer to "guide (PDF: 3,209KB) of exclusive water supply of Yokohama-shi" for precautions at the time of laying construction confirmation application whether it corresponds to exclusive water supply.

Water supply laying work refers to the construction of new construction, expansion, and remodeling of water supply facilities.
(Reference) Article 3, Paragraph 10 of the Water Supply Act
In this Act, "laying water supply" refers to the construction of a new water supply facility or the construction of an extension or remodeling specified by a Cabinet Order.
(Reference) Article 3 of the Water Supply Law Enforcement Order
Construction of expansion or remodeling of water supply facilities specified by a Cabinet Order prescribed in Article 3, Paragraph 10 of the Act shall be listed in the following items.
1 Construction pertaining to changes in the maximum daily water supply, type of water source, intake point or water purification method
2 Construction related to new construction, expansion, or large-scale remodeling of sedimentation ponds, filtration ponds, water purification ponds, disinfection equipment or distribution reservoirs

"New establishment of water supply facilities" means water supply facilities, that is, water intake facilities, water storage facilities, water supply facilities, water purification facilities, water transmission facilities, and water distribution facilities, and all or any of these facilities are newly installed completely. Says.

“Expansion or remodeling work specified by a Cabinet Order” refers to large-scale or important part construction work, as specified by a Cabinet Order.
・Construction pertaining to changes in the maximum daily water supply, type of water source, intake point or water purification method
・Construction related to new construction, expansion, or large-scale remodeling of sedimentation ponds, filtration ponds, water purification ponds, disinfection equipment or distribution reservoirs
That's right.
“Construction related to this” includes not only the construction itself, but also incidental work and related work required for the construction.
"Construction related to large-scale remodeling" refers to remodeling work related to a substantial part of the facility.

Water supply facility standards are stipulated by the Water Supply Law, etc.

(Reference) Article 5 of the Water Supply Law
The water supply shall have all or part of the intake facility, water storage facility, water supply facility, water purification facility, water supply facility, water supply facility, water supply facility, water distribution facility, according to the quality and quantity of raw water, geographical conditions, form of the water supply, etc. Each facility must have the requirements listed in the following items.
(1)The intake facility must be able to take in the required amount of high quality raw water as much as possible.
(2)The water storage facility must have the water storage capacity necessary to supply the required amount of raw water even in the event of drought.
(3)The water supply facility must have pumps, water pipes and other equipment necessary to send the required amount of raw water.
(4)Depending on the quality and quantity of raw water, the water purification facility has a sedimentation pond, a filtration pond, and other equipment necessary to obtain the necessary amount of purified water that conforms to the water quality standards set forth in the preceding Article, and has a disinfection equipment Have.
(5)The water supply facility must have pumps, water pipes and other equipment necessary to send the required amount of purified water.
(6)The water distribution facility must have a reservoir, pump, water distribution pipe and other equipment necessary to continuously supply the required amount of purified water at a certain level of pressure.
2 In determining the location and arrangement of water supply facilities, the laying and maintenance of water supply must be as economical and easy as possible, and the certainty of water supply must be considered.
(3) The structure and material of the water supply facility must have sufficient strength against water pressure, earth pressure, seismic force and other loads, and must not be contaminated or leaked.
4 In addition to what is provided for in the preceding three paragraphs, the necessary technical standards for water supply facilities are required to obtain water purification that conforms to the water quality standards set forth in the preceding Article, or to maintain the water quality of the purified water. Technical standards are specified by Ordinance of the Ministry of Land, Infrastructure, Transport and Tourism and Ordinance of the Ministry of the Environment) (outside site).

When laying a dedicated water supply, etc., a laying construction confirmation application is required in advance.
Please contact Health and Welfare Center Health Sanitation Division in the facility area.

• Exclusive water supply laying construction confirmation application (word: 24KB)
• Construction design document (word: 21KB)
• Dedicated water supply laying construction confirmation application change items registration form (word: 26KB)

According to the provisions of Article 20, Paragraph 1 of the Water Supply Law, dedicated water supply installers are required to carry out regular water quality inspections as specified by Ordinance of the Ministry of the Environment. Regular water quality inspections include "inspection of color, turbidity and residual chlorine once a day" and "inspection performed approximately once a month".
In addition, in accordance with the provisions of Article 15, Paragraph 6 of the Water Supply Law Enforcement Regulations, the installer must formulate a water quality inspection plan that takes into account the water source of the water supply and the surrounding situation before the start of each business year. Hmm.
The installer must promptly report the results of the water quality inspection to Health and Welfare Center Health Sanitation Division, where the facility is located.

• Dedicated tap water quality inspection plan (Excel: 37KB)
• Exclusive tap water examination plan manual (word: 14KB)
• Guide for exclusive tap water examination plan development (PDF: 223KB)
• Water quality inspection result report (word: 25KB)

According to the provisions of Article 22-2 of the Water Supply Law, the dedicated water supply installer must maintain and repair the water supply facilities in good condition according to the provisions of Ordinance of the Ministry of Land, Infrastructure, Transport and Tourism.

(Reference) Article 17-2 of the Water Supply Law Enforcement Regulations
1 Considering the structure, position, maintenance or repair of the water supply facilities and other water supply facilities (referred to as "the situation of water supply facilities" in the next issue), the operating conditions of the flow rate, water pressure, water quality and other water supply facilities Monitor and patrol the water supply facilities at an appropriate time, and take cleaning and other necessary measures to maintain the water supply facilities.
2 In consideration of the situation of water supply facilities, conduct inspections at appropriate times by visual inspection or other appropriate methods.
3 Inspections in the preceding item are limited to concrete structures (limited to those that have watertightness and can be visually observed within the range that does not affect the operation of water supply facilities. The same shall apply in the following paragraphs and paragraphs 3. ) Shall be performed at least once every five years at an appropriate frequency.
4 When it is determined that there is damage, corrosion or other deterioration or other abnormalities in the water supply facilities by the inspection or other method of the second item, repair and other necessary measures shall be taken to keep the water supply facilities in good condition. thing.

Installer of exclusive water supply needs to perform various reports based on the Water Supply Law.
・When water supply of exclusive water supply start registration form (word: 18KB)
・When we set up water supply technical manager of exclusive water supply water supply technology manager setting report (word: 19KB)
・When we changed water supply technical manager of exclusive water supply water supply technology manager change report (word: 19KB)
・When water supply of exclusive water supply is urgently stopped, exclusive water supply emergency stop report (word: 18KB)
・When we entrust technical duties about management of exclusive water supply to the next person exclusive water supply management business consignment registration form (word: 21KB)
・registration form (word: 20KB) when contract related to the outsourcing of technical services related to the management of dedicated water supply has expired
・Dedicated water supply management business Consignment When the matters described in registration form (excluding the scope of the commissioned business or the contract period) are changed, the dedicated water supply management business consignment change registration form (word: 20KB)
　※If you want to change the technical manager of the contracted water supply business, please use the "Dedicated water supply management business consignment change registration form".

Facilities with an effective capacity of the receiving tank exceeding 10 cubic meters are called simple dedicated water supply, and facilities with an effective capacity of the receiving tank of 10 cubic meters or less are called small-scale receiving tank water supply. However, this excludes those used only by one household.
(Reference) Article 3, Paragraph 7 of the Water Supply Act
In this law, "simple dedicated water supply" refers to water supply used for the water supply business and water supply other than the dedicated water supply, which uses only water supplied from the water supply provided for the water supply business as the water source. However, this excludes facilities whose size of facilities to be used is less than the standard specified by a Cabinet Order.
(Reference) Article 2 of the Water Supply Law Enforcement Order
The standard specified by a Cabinet Order prescribed in the proviso of Article 3, Paragraph 7 of the Act shall be that the total effective capacity of the water tank provided to receive water supply from the water supply used for water supply business is 10 cubic meters. .
(Reference) Article 2 of the Ordinance on Securing Safe and Sanitary Drinking Water in Yokohama City Simple Water Supply and Small Water Tank Water Supply
(6)Small-scale water tank water supply: It is a water supply other than a water supply, a dedicated water supply, and a simple dedicated water supply to be used for the water supply business, and only the water supplied from the water supply provided for the water supply business is used as a water source, and a water tank is provided to receive the water. Means that supplies drinking water. However, this excludes those supplied exclusively to a single house.

The following management is required for simple dedicated water supply and small-scale water tank water supply.

・After the start of use of the building (after the start of water supply), a notification of the start of water supply shall be promptly notified to the Health and Welfare Center Health Sanitation Division.
※Start of simple dedicated water supply registration form (word: 23KB)
※Start of small-scale water receiving tank water supply registration form (word: 27KB)
・If the facility is changed to the contents of registration form or the facility is abolished, a notification shall be made promptly.
※Change / Abolished registration form (word: 26KB)
※Change / Abolished registration form (word: 26KB)
※There is no need to submit a notification for the water tank used in a single home.

Periodic at least once a year
※Please refer to the following paragraph "Cleaning of simple dedicated water supply and small-scale water tank water supply".

Periodic at least once a year
※Installers of small-scale receiving tank water supply with an effective capacity of more than 8 cubic meters and all "underground receiving tanks, etc." are required to take a management status inspection.
"International receiving tanks, etc." refers to small receiving tanks that fall under any of the following.
(1)The ceiling, bottom or surrounding wall of the receiving tank is also used with other parts of the building.
(2)(1)In addition to what is specified in, whether a part of the outer surface of the receiving tank is installed in contact with the ground, or where all or part of the receiving tank is buried.
※Please refer to the following paragraph "Inspection of the management status of simple dedicated water supply and small-scale water tank water supply".

・Perform simple daily water quality tests (color, turbidity, smell, taste).
※If something goes wrong, contact Health and Welfare Center Health Sanitation Division immediately.
・Perform facility inspections and make necessary repairs.

・Stop water supply.
・Inform users not to drink water.
・I will contact Health and Welfare Center Health Sanitation Division immediately.

Cleaning of the receiving tank is required to be performed regularly at least once a year.
It is recommended that the cleaning of the receiving tank be outsourced to a specialized cleaning company.
If you do not know the nearest cleaning company, please contact the following organizations.
※The next organization is group organized by registration company (building drinking water tank cleaning business) of the mayor or Kanagawa governor.

※You may need to apply to Water Works Bureau when cleaning the receiving tank or draining the water stored in the receiving tank.
　For more information, please see the Water Works Bureau Service Promotion Section page.

Installers of simple dedicated water supply and small-scale water tank water supply (those with an effective capacity of more than 8 cubic meters and all "underground water receiving tanks") are required to undergo a management status inspection at least once a year. .
For inspection organizations
・In the case of a simple dedicated water supply, a simple dedicated water supply registration inspection organization
・In the case of small-scale water receiving tank water supply, small-scale water receiving tank water supply / simple water supply designated inspection organization
So, please choose freely and take the inspection.
In addition, please refer to inspection organization about inspection rate (not fixed rate) 。

In the management status inspection, the following items are checked.

• Situation around the aquarium
• Status of the tank body
• Status at the top of the aquarium
• Condition inside the aquarium
• Manhole State
• Status of overflow pipe
• Condition of ventilation tubes
• Condition of drain pipe
• Water pipes, etc.
• Simple water quality tests (odor, taste, color, chromaticity, turbidity, residual chlorine) in hydrants
• State of arrangement and preservation of documents

※We publish inspection organization which concludes agreement with Yokohama-shi as water supply management conformity facility indication system agreement organization.
There are other institutions that can inspect simple dedicated water supply, so please see the Ministry of Land, Infrastructure, Transport and Tourism website (outside site) for details. .

Installers of small-scale water tank water supply (those with effective capacity of water receiving tank exceeding 8 cubic meters and all "underground water receiving tanks") and simple water supply water supply are promptly notified of the inspection results after taking the management status inspection. It is mandatory to report to the mayor.
In addition, it is necessary for installer of simple exclusive water supply to report the result to health center director regardless of whether there is any nonconformity after taking the management status inspection.

[Report Form]

• In the case of a simple dedicated water supply…Simple dedicated water supply inspection test report (word: 21KB)
• In the case of small-scale water tank water supply…Small-scale receiving tank water supply test result report (word: 26KB)

Installer of small-scale receiving tank water supply (except "underground receiving tank") with effective capacity of receiving tank of 8 cubic meters or less performs inspection of facility after cleaning conduct and reports inspection result to the mayor promptly Is required.
[Report Form]

• Small-scale receiving tank water supply self-inspection result report (word: 26KB)

In Yokohama City, facilities with good results of periodic inspections of the management status are certified as "water supply management conformity facilities", and the registered inspection organization that has concluded an agreement with Yokohama City will display the water supply management conformity facility indication mark (plate) and display deadline seal Has been issued.
The water supply management conformity facility display mark (plate) can be posted at the entrance of the facility so that users and users can understand that the management status is good.

When newly installing or replacing a receiving tank, an elevated water tank, etc., we will conduct a preliminary examination by drawing on the installation location of the tank and the structure of the tank.
Before applying for building confirmation or before applying for water supply equipment construction (if you do not have a building confirmation application), please contact Health and Welfare Center Health Sanitation Division in the ward where the water tank is installed.
The drawings required for the examination are as follows.

• Layout of buildings
• Floor plan and elevation of the aquarium
• Floor plan and elevation of the water tank installation location
• Water supply and drainage system diagram
• Water supply statement

• Outline of Administrative Procedures for Pre-Guidance of Yokohama City Reservoir Facilities
• Receiving tank facility prior consultation slip (PDF: 177KB)

Simple water supply is a private water supply other than a dedicated water supply using groundwater as a water source.
(Reference) Ordinance Article 2, Paragraph 1, 5 on Securing Safe and Sanitary Drinking Water in Yokohama City Simple Water Supply and Small Water Tank Water Supply
Simple water supply: Water supply other than water supply used for water supply business and dedicated water supply, which supplies drinking water using groundwater as a water source. However, this excludes those supplied exclusively to a single house.

When performing laying work, etc., it is necessary to apply for laying work confirmation in advance.
Please contact Health and Welfare Center Health Sanitation Division in the facility area.

• Simple water supply laying construction confirmation application (word: 25KB)
• Construction design document (word: 18KB)
• Change of items described in simple water supply laying construction confirmation application registration form (word: 26KB)

Before the start of each business year, the installer of the simple water supply water supply must create a water quality inspection plan that takes into account the water source of the water supply and the surrounding situation, and carry out water quality inspection based on the plan.

• Simple water supply tap water examination plan (Excel: 33KB)
• Simple water supply tap water quality inspection manual (word: 14KB)
• Guide for simple water supply tap water examination plan development (word: 23KB)

Simple water supply is required to be cleaned and managed regularly at least once a year.
About inspection of the management situation, please have you choose from "small water receiving tank water supply, simple water supply designation inspection organization" mentioned above, and please take inspection.
In addition, please refer to inspection organization about inspection rate (not fixed rate) 。
Immediately submit a simple water supply test result report (word: 26KB) to Health and Welfare Center Health Sanitation Division in the district where the facility is located.

There are many wells in Yokohama City, which are used for domestic water such as watering. In addition, some citizens drink with tastes for reasons that they have been drinking for a long time or delicious.
However, in Yokohama City, where urbanization has progressed, well water and spring water may be contaminated due to infiltration of various harmful substances underground and inadequate management of wells, etc. It may change.
In order to always conform well water to tap water quality standards (51 items (outside site)) and use it for drinking, chlorination, advanced water treatment, and maintenance for it are required. In addition, it may be difficult to improve water quality.
In Yokohama City, water supply is maintained in almost all areas, so it is recommended that well water be used as domestic water other than drinking water and tap water be used for drinking water.
In addition, please refer to Water Works Bureau customer service center (telephone 045-847-6262, fax 045-848-4281) or Water Works Bureau water supply maintenance section about laying of water supply.

Yokohama City is looking for wells (disaster emergency wells) that will be provided to local people as domestic water such as washing water in the event of a disaster as "securing domestic water in the event of a disaster."
For details, please see here (page of information about hygiene measures at the time of disaster).

In Yokohama City, we aim to reduce the number of water receiving tank facilities by expanding the direct water supply system.
Even in buildings and condominiums that use the receiving tank system using the receiving tank system, switching to this direct water supply system will allow water from the distribution pipe to be supplied directly to the faucet.
In addition, since there is no need for a receiving tank, it is possible to reduce the maintenance of management fee and make effective use of the installation site.
For more information, please visit the Water Works Bureau page.

The direct connection water supply system is a direct connection direct pressure water supply system that can supply water to the 4th floor without installing a pressure booster pump, and a pressure booster pump. ※Although it is necessary to install, there is a “directly connected booster water supply system” that can supply water up to about 200 households on the 15th floor.
※The installer of the booster pump will be responsible for the customer (user).

There are two types of water supply methods: a direct water supply system that uses the water pressure of the water pipe to supply water, and a water receiving tank system that installs a water receiving tank to supply water. Each water supply system has its advantages and disadvantages as shown below, so it is desirable to take these into account and adopt the optimal water supply system.
Condominiums that are considering replacing water tanks, pumps, and water pipes due to deterioration of water receiving tanks and aging water pipes should be changed to a safer and more sanitary direct connection water supply system. I recommend.

Put water in a colorless and transparent glass without dirt, and when viewed from above, it may be colored.
Normally, water is colorless and transparent, but sometimes it looks blue because light scatters a short blue color with a wavelength. This is normal, but sometimes white water, red water, black water, green water, etc. may come out.
Also, when the water is colored to the extent that it is not desirable in appearance, it may have taste and smell.
Tap water is chlorinated, so it smells chlorine. This is safe water that can be drunk with peace of mind, but in addition to chlorine odor, mud smell (contamination of sewage, etc.), sweet (production of diatomaceous), mold odor (production of radiobacterium and cyanobacterium), chemical odor (factory drainage) Etc.).
If you feel any abnormality, please contact Water Works Bureau Customer Service Center (Tel: 045-847-6262, Fax: 045-848-4281) (if you do not know the water supply system) or Health and Welfare Center Health Sanitation Division (if you do not know the water supply system).
※The smell and taste are hard to feel when the water temperature is low, so it is a good idea to warm it to about 40 degrees before smelling the smell.
(Reference)
Yokohama City Inst. of Health "Information on Water" page

Pump water in a transparent cup and leave it for a while, and if the turbidity disappears from the bottom, it's okay because the air is only mixed and white.

Red water is probably due to the old water pipe and iron rust. Please use the first water in the morning as miscellaneous water instead of drinking.
Fundamentally, it is necessary to replace old water pipes.

It may cause foaming if water is released vigorously. If the foam disappears after a while, it's okay because the air has been drawn into the water.
In addition, detergent may remain in the container and bubbles, so rinse thoroughly before checking.

There is no effect on the human body due to the appearance of minerals contained in tap water.

Tiles and draining baskets may discolor black, purple, or pink, but this is thought to have proliferated with bacteria and mold in the air on the droplets attached to the tiles.
If the color changes, wash it off with a commercially available detergent or bleach, and dry it well after washing.

Cracks may occur in the underground receiving tank due to the effects of the earthquake, so if an earthquake occurs, carry out the following inspection.

• Please carry out check about the situation of "water of hydrant" and "around tank and inside" listed in handbill (about emergency inspection of underground receiving tank) (PDF: 420KB).
• If any abnormalities are found as a result of the inspection, please contact Health and Welfare Center Health Sanitation Division in the district where the facility is located immediately.

Please check the facilities every day while the aftershock continues.

Information on the water supply cooperative water tank certification system during a disaster

If you do not know the water quality inspection company, please contact the following specialized company.
※The following organizations are water quality inspection organizations in the city that have been registered by the Minister of Land, Infrastructure, Transport and Tourism and the Minister of the Environment.

• Receiving tank Q & A-To those who have installed the receiving tank-(PDF: 952KB)
• We recommend tap water for drinking water (PDF: 465KB)
• Hygiene management of building water-Is your building okay? Accident Casebook-(PDF: 1,828KB)