Drainage experts by Ragman

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Any drainage experts out there?

I need to clear blocked 4" drains, I can pressure wash the blocked pipes (several meters of them) but I don't want the 'dirty water' to flow down already cleated sections and potentially reblock them.

I need a dirty water pump that can handle solids (say 18mm) but it cannot be a submersible pump as the only access I have is via a 4" drain

Any help appreciated

Posted 19 Jun 2011, 19:39 #1 

Depends what the blockage is and I would not worry about dirty water flowing down cleaned sections.

There could be two potential problems:

Some object/ build up is blocking it

The pipe has collapsed.

From hire shops you can hire drain rods. On the end you can put a rubber disc and this can be used to rapidly pushed down the pipe. This will cause pressure, provided there is water present and either clea or compact the blockage. The other end you can get has sprials of wire. This you can 'screw' into the blockage and pull it apart.

Collapsed pipe - then it is a dig out and replace

"Don't think of them as problems, think of them as opportunities."
"OK, I think I've hit an insurmountable opportunity!"


Posted 19 Jun 2011, 20:32 #2 

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There's an adaptor you can get for a pressure washer, It's the same think drain jetting companies use. Part of the flow goes forward to break up the blockage, some goes backwards to drive the head through the blockage.

Drain rods can be quite succesful if the drains are not collapsed. I've cleared blockages with the rod alone, from the blocked side and that was two full drain rod sets down the system. Be very careful though not to turn the rods the wrong way and unscrew them as this only adds to the blockage. I think we did it three times before I figured out what the problem was and made her stop it (no, don't ask).

Posted 19 Jun 2011, 20:41 #3 

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Thanks - background for this is moving into new house last year so still dealing with previous poor maintainence. Issue is I had a blocked drain that I assumed was a soak away, I cleared 7M of it today with pressure washer drain hoses, basically liquifying years of debris and then bailing it out of the 4" access pipe. It appears it is not a soak away but a drain and it looks like all the downpipes from the house feed into the same drain but there is at least 10m of 4" pipe between the access pipe I have and the nearest of the downpipes, so what I am trying to avoid is when pressure washing the blockage away is the accumulated bebris to flow down into the section already cleared - hence the need for the pump

I have drain rods and drain cleaning hoses for the pressure washer

Posted 19 Jun 2011, 21:12 #4