Old (but new) Precast Concrete Sanitary Lines - Never Put in Service 1

[JoelTXCive]

We have a municipal client with existing concrete sanitary lines that were installed ~48 years ago. After installation the lines have sat unused (for the most part). The land was not further developed.

A developer is now looking at completing the development of the project.

The municipal client would love this, but wants input on what they can do to verify the lines are good.

They also want the developer to do any improvements/repairs/upgrades now versus the municipality having to do maintenance 2 years from now.

What sort of due diligence/testing can be done to verify the condition of the lines?

What sort of issues might the lines have?

We can video all the lines, but are there other structural issues that might be there that do not show up?

It is approximately 2,500 LF of 15” and 18” lines and 14,000 LF of 8” lines.

Thank you in advance.

 

[cvg]

video and leakage test should be done first. that will give you a good idea of any potential structural issues

 

[bimr]

Agree with cvg. Physical condition assessment, using CCTV, pole mounted zoom camera inspections, and sanitary sewer evaluation technology

 

[EdStainless]

It would be good to do a survey and verify the elevations. Are they what you expect? Has there been any shifting? We have had unused lines do funny things.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[cvg]

manholes can be surveyed, but the bigger concern is pipe settlement. the lines may need to be cleaned out prior to video. any low spots in the pipe will fill with water which can easily be observed in the cctv inspection

 

[BridgeSmith]

I would be more worried about degradation of the seals between the sections (assuming there were any), than the structural integrity of the concrete. The pipes themselves will be stronger now than they were when they were put in, but if there were rubber seals, they may have disintergrated. If that's the case, you could probably do a liner for the bigger lines; I don't if there are lining processes for 8" lines.

Rod Smith, P.E., The artist formerly known as HotRod10

 

[bimr]

It is possible to line pipes at least as large 5' diameter. However, physical condition assessment is always performed first.

 

[JoelTXCive]

This was all good input. I passed on to the people in our public infrastructure group. If I hear what the municipality does, then I'll report back.

Thank you!