Water quality

If the water is white, pour it in a transparent container and leave it for a while. If there is no sediment and it becomes transparent from below, it is probable that the air in the tap water became fine bubbles and the water looked white. In this case, there is no problem for drinking. If there is sinking and it is not clear, stop drinking and call the Water Works Bureau Customer Service Center. I'll ask you for a water quality test.
Red water may come out when using iron pipes (zinc plating steel pipes). Drinking is acceptable if it becomes transparent after flowing about a bucket. If you are worried, we will ask you for a water quality test.
If black or blue water comes out, stop drinking and contact us. Water quality tests by Water Works Bureau are free.

For tap water, the government has established tap water quality standards that fully consider safety, and water utilities across the country are obliged to comply with and inspect them.
According to Article 4 of the Water Supply Law, water quality standards for tap water include six requirements, such as not being polluted by pathogenic organisms and not toxic substances. As a specific standard, 51 standard values are set in the ministerial ordinance on water quality standards.
In Yokohama City, we independently set water quality management values that are stricter than national standards, and by properly managing water quality from water sources to faucets, we supply safe and high quality water to customers.

In Water Works Bureau, we go to the homes of customers who wish to conduct water quality tests and conduct free water quality tests at the faucet.
To apply, please contact the Water Works Bureau Customer Service Center.
In addition, in large-scale condominiums and buildings, etc., where the effective capacity of the receiving tank exceeds 100 cubic meters, etc., corresponds to a dedicated water supply, a water supply technology manager in charge of technical work related to water supply management is set up. Because it is, it is excluded from this water quality inspection.

If a lead water pipe is used for your home water pipe, a small amount of lead may dissolve into the accumulated tap water. Please use the first water in the morning except for drinking. There is no health problem with drinking water after drinking.

• Response to lead water pipes

The management and water quality of water supply facilities from receiving tanks to faucets in condominiums and buildings was under the jurisdiction of the Health and Social Welfare Bureau. However, due to hygiene problems caused by inadequate management, the Water Supply Law was revised in June 2001, and the Water Works Bureau, which supplies water, was involved in the management of water tanks.
In Yokohama City, the Water Supply Ordinance was revised in December 2002, and the following measures are taken.
（1） In response to requests from users of water tanks (residents), Water Works Bureau will conduct water quality tests at the faucet of each house free of charge and inform them of the results.
（2） As a result of the water quality inspection at the faucet, if there is a problem with the safety of the water quality, jointly conduct water quality inspection and inspection in the water receiving tank in cooperation with the Medical Care Bureau, and it is recognized that it is necessary to manage the water tank water supply If so, we will give guidance, advice and recommendations to the installer of the water tank water supply. Water quality inspections are not included in the Water Supply Law Enforcement Regulations, but are not included in the Water Supply Law.
（i） High interest of users in water quality
（ii） Equalize services with users of detached houses, etc.
（iii） Considering that water quality inspection is necessary to judge the management situation of water tank water supply, we made the regulations as Motoichi original correspondence.
In addition, the contents of the management responsibility of the water tank water supply installer based on the Water Supply Law and the ordinances under the jurisdiction of the Medical Care Bureau ("Ordinance on Securing Safe and Sanitary Drinking Water in Yokohama City Simple Water Supply and Small Water Tank Water Supply") remain unchanged.
However, in the case of large-scale condominiums and buildings with an effective capacity of the receiving tank exceeding 100 cubic meters, etc., a water supply technology manager in charge of technical work related to water supply management is set up. Because it is excluded from this water quality inspection.