HI Carmela:
I have been involved with 1/2 dozen projects involving relining of old cast iron pipes. Some of the projects have been in service for more than 20 years. Most of the pipes relined were installed in the 1890s and early1900's. Each of the projects were successful at restoring flow capacity and improved water quality to the areas served.
The lining process was selected because the cost of replacement was high due to being in relatively high traffic areas (i.e.: in state highways, highly commercialized areas, significant number of other utilities in the area, etc.). The lining process itself has a relatively high cost, so, there would be a few things you might like to consider before selecting it like: the host pipes should be without any significant history of breaks, the soil should be known to be generally not "highly corrosive", anything that might cast doubt on the condition of the existing pipe barrel.
There are other trenchless restoration processes that have become available recently. I haven't used any, but, some appear to be able to be used in instances where the pipe barrel may be in question.
Hope this is some help to you.
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Bart Clark , PE
Warren CT
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Original Message:
Sent: 07-26-2018 08:19
From: Carmela Roberts
Subject: Cleaning and Relining Pipes vs. Replacement
A local town has 80 year old cast iron pipes used for water distribution. Does it make any sense to clean and reline the pipes or should they be replaced entirely? Does anyone have experience with older water systems using cast iron pipes? And what is a realistic life span?
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Carmela Roberts P.E., M.ASCE
President
Roberts Engineering Group LLC
Hamilton NJ
(609) 586-1141
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