Removal / Rehab of Failed Poly-Liners (HDPE)

[FL21USF]

The work is in SW Florida. Several failing 22" & 18" clay and concrete sanitary sewer pipes were rehabbed with HDPE. However, the annular space was not grouted. In several spots the pipes have collapsed or the joints have come apart. The infiltration of sand is causing potholes in the roadways.
The client would like to CIPP the pipes. If you have any experience on removing poly-liners from collapsed pipe or have been able to rehab a similar system, I would appreciate your comments.

Thanks - Mike

 

[BobPE]

FL21USF:

I have had the opportunity to work on sever rehab projects, unfortunately, they involved complete main replacement. It seems that the sales hype for these sytems ignored groundwater infiltration pressures, which, like in your case, caused the collapse of the liner system. One project was a system to line a DIP river crossing, where the head pressure from the river was 8 feet, which would not seem like a lot. The water traveled in the space between the HDPE and the dip main and leaked where the pipe entered the manhole. We tried pulling it out, excavating into the pipe several feet, but to no avail. I paralled the pipe with another 12 DIP main, which worked quite well, but the whole thing was rather expensive.

Sorry I dont have anything positive to say, I am lucky it was not my design in the first place to line the main. I just wanted to let you know there are people who replace the mains since if that becomes an option, you wont feel alone in making the recommendation.

Good luck with your problem.

BobPE

 

[dicksewerrat]

Contact me for info on Rehabing these pipes. I work in the industry but can't solicit business here. Contact info in profile.