Leakage Prevention Guidebook - Bureau of Waterworks Tokyo ...

More documents

Recommendations

Info

found, On the other hand, the new leakage increases gradually in accordance with time. This is referred to as the“repetition phenomenon” of leakage. As the solution to this repetition phenomenon may lead to leakage preventionmeasures, we are trying to understand this phenomenon. (Fig. 3)Leakage volume(m3/day)preventionvolumepreventionvolumeRepetitionvolumeRemainedleakagevolumeRemained leakage volumeThe second last time The last time ,owRecurring yearsFig.3Repetition of leakage1.2 ,ecessity of leakage preventionTokyo currently possesses water resources that supply a volume of 6.3 million cubic meters per day. This volumeincludes additional water supplied through yearly agreements with Kanagawa Prefecture and Kawasaki City as well asfrom the Sagami River, the stability of which is affected by the state of water in Kanagawa.Furthermore, due to the level of rainfall in recent years and the fact that planned dam construction is as yet incomplete,the actual supply from dams and other facilities in the Tone River system, which is responsible for roughly 80% ofTokyo’s water, is about 20% below initial estimates. These issues result in the low level of safety regarding drought.In consideration of these circumstances, we are required to work on securing stable water resources by water resourcesdevelopment such as development of dams, as well as to further promote measures for effective use of water and leakageprevention.On the other hand water distribution pipes installed within municipal Tokyo totals up to 26,000 kilometers as of FY2010,which is worth more than halfway around the world.Water pipes embedded under ground are constantly subject to a danger of leakage, and when leakage occurs, these pipespose risks of factors like secondary disasters including poor water flow, sagging road, inundation and so on.Leakage prevention measures are actively implemented as one of main initiatives of the Bureau, since such measureshave effects equivalent to a new water resources development, and that they prevent secondary disasters from occurring.- 2 -
Fig.4-1Scene of water leakageFig.4-2corrosion and water leakage of iron pipes- 3 -
Page 1: Leakage Prevention Guidebook2011Bur
Page 4 and 5: 3.4 Time integral type leakage dete
Page 8 and 9: 2 Countermeasure of leakage prevent
Page 10 and 11: (2) Integration of service pipes un
Page 12 and 13: In 23 wards, we have long addressed
Page 14 and 15: next generation and improvement of
Page 16 and 17: Fig.12Portable minimum flow meter3.
Page 18 and 19: unaffected by traffic noise or layi
Page 21 and 22: conductivity detector, or precise m
Page 23 and 24: 5 Annex- 19 -
Page 25 and 26: Table-2 Trends in total distributio
Page 27 and 28: Table-5 Organization of water leaka
Page 29 and 30: Table-7 Trends in percentages of du

Leakage Prevention Guidebook - Bureau of Waterworks Tokyo ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?