Water Quality and Water Resources
Today’s Water Quality
|： 131 water taps in the Tokyo Metropolitan Area|
|： Purification Plants|
|For inquiries in relation to the cities of Musashino, Akishima, Hamura, and the village of Hinohara, please contact the Water Supply Departments of those local government agencies.|
Mar 20(Tue), 2018
131 water taps in the Tokyo Metropolitan Area have installed automatic water quality meters. Every day at 9 a.m. we update the data obtained from the meters about “residual chlorine concentration”, “turbidity” and “color”.
*Because the data are preliminary figures, those figures may be corrected at a later date.
*From April 1, 2016, the automatic water quality meter at Station No. 45 has moved to Toyosu in Koto-KU
|Residual chlorine concentration data for 131 water taps in the Tokyo Metropolitan area (as of 9 o’clock this morning.)
The numbers of each water tap, together with their locations, are shown on the map above.
|Tap No.||Residual chlorine concentration||Tap No.||Residual chlorine concentration||Tap No.||Residual chlorine concentration||Tap No.||Residual chlorine concentration||Tap No.||Residual chlorine concentration|
The results for turbidity and color are here.
|Explanation of Terms|
Chlorine, which is used as a disinfectant, is present in the water supply in extremely small concentrations.
|Turbidity||This indicates the degree of muddiness of water. This is a matter of judgement as to whether the water from the public water supply meets the requirement of being “almost completely colorless and transparent in appearance” according to standard criteria of 2 degrees or less. Where this is achieved, this can be called clear water, free from muddiness. However the Bureau of Waterworks Tokyo Metropolitan Government sets an ever stricter standard of no more than 0.1 degrees.|
|Color||This shows the color of the water and this is a matter of judgement as to whether the water from the public water supply meets the criteria of being “almost completely colorless and transparent in appearance. Water whose color is no greater than the standard value (a range of 5 degrees or below) is considered colorless. However the Bureau of Waterworks Tokyo Metropolitan Government sets an even stricter standard of no more than 1 degree.|