Sealing sanitary manholes from the inside 1

[civilcorruption]

Can anyone tell me how to effectively seal a sanitary manhole from the inside? I have about 8 MHs full of water.

I'm pretty sure ground water is infiltrating through the barrel joints and or pipe connection in several of these new manholes. The contractor tells me He used rubber gaskets around all the barrel joints. So unless they twisted during installation, Im not really sure what is going on. The manholes are still under warranty but I'd hate to have him dig them all up.
Putting concrete around the inside of the barrel will almost certainly fail due to the direction of ground water forces.
Important to seal because it is a forcemain system and the manholes house the valves and air-relief componants.

 

[dicksewerrat]

Can the manholes be pumped dry? or dewatered with well points? Then you can watch as they refill and see where the leaks are. You could seal them with a CIPP manhole liner. did you use a neoprene collar for all pipes as they enter the manhole?

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[cvg]

If they leak and are under warranty, why hesitate to have the contractor fix the mistake?

 

[mitchell54]

There is a product on the market that works very well. I had the same problem with older manholes in FL. I went in and evacuated the contents (water) and looked for the leaks then using a demo / hamerdrill (don't go cheap get a good one)drilled a 3/4" hole and injected the product. Within seconds then leaks are fixed. The name of the Product is Sealguard.

http://www.sealguardinc.com/html/sealguard2.html

Checkout there website..

 

[jmrosell]

i have also used the injectable foam to seal leaks in a wetwell. if the project is still under warranty i would make the contractor figure out how to fix it and just make sure that it meets your standards.

 

[LHA]

dick and mitchell have great suggestions...IF it is your problem. If you are working for the installer, then you must spec something, of course. But, if not, don't make it your problem by spec'ing a solution.

If it is in warrantee, and you spec the solution and it fails, you've probably just taken over responsibility. Check with your lawyer, but I think I am correct.

If you just tell the installer they don't meet spec - you certainly have a hydro. test spec'ed, and that test certainly requires watertightness to be demonstrated - the installer must try things until they do.



Remember: The Chinese ideogram for “crisis” is comprised of the characters for “danger” and “opportunity.”
-Steve

 

[rustynightowlovo]

after ten years of sales in precast manholes it sounds like your installor did not install conseal in between cyc.and cones or adjustment rings or he did not jack the boots with boot jack hyd to the pressure the boot manufacture requires, in the manhole to the right spec or he did not tighten the clamps on out side of the boot to the pipe to make waterproof seal from pipe to manhole. our regs here say that the manhole is to be vaccumn tested to 2psi for ten minutes to prove they are waterproof look on spec for your eng as to what kind of test they were suppose to meet for the job and the city or county reg.s if he didnt use the right lifting device to place manhole he could have gotten dirt in between seals and they wont seal then. we have used trough seal mixed to pancake thighness and pack joints about 4" out passed joint. make sure the joints have been cleaned and washed and dried then use the bonding agent when mixing throughseal dont use water and do not reused or add water to it after you start throw away mix new batch. step holes are great for leaks if they dont use them and or you have bad or cracked precast material.