Hello,
Sorry for cross-posting.
I am posting the following request for a colleague, who has trouble to
post to the list.
Thanks in advance for your advice.
Eran Friedler
PS I'll forward any message to him
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Dear Sirs,
This is to request information on any regulations/directives/guidelines
pertaining to regular maintenance and operation of large diameter sewage
pipelines.
We have recently had a break in a 50` Asbestos/Cement pressure sewage pipe,
in use for 30 years, carrying some 200,000 M3/day, which caused heavy
pollution of the beach.
At the bottom of the pipe an irregular u-shaped groove was revealed, of a
width of approx. 3-4 cm and depth of 3-20 mm. The pipe wall is 65 mm thick.
The water company operating the pipe claimed they have done regular visual
checks on the pipe near the manholes and never saw anything wrong.
There were no evident signs of corrosion on the inner wall. The break took
place in parallel to the groove, at a distance of about 2-3 cm.
We would greatly appreciate any help in elucidating the possible causes of
the break as well as any means which can detect such faults if used as part
of a routine maintenance and checking program.
We are also interested in information on regulations/ directives/ guidelines
on proper maintenance and operation of sewage pipelines (including pumping
station).
This relates to periodic checks/tests, photographing, Ultrasonic tests,
visual checks, measures to prevent water hammer, checking of old (above 30
years) pipes, etc.
Thanks for your help
Sincerely,
Baruch Weber
Ministry of the Environment
Israel
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Dr. Eran Friedler
Department of Civil and Environmental Engineering
Division of Environmental and Water Resources Engineering
Technion - Israel Institute of Technology
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Haifa 32000, Israel
Phone: +972-4-8292633 Mobile: +972-52-222355 Fax: +972-4-8228898
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