This is what we commonly encounter when unblocking and cleaning blocked drains across the North West.
We attended this job yesterday evening in Eccles upon attendance we was told that both male and female customer toilets were backing up. We found a manhole chamber in close proximity and opened it up to take a look-see.
Once opened up (picture right top) we found that the man hole chamber was completely blocked and looked like it had been for a while. You may not want to look to closely but you can see just see the top of a plastic pipe surrounded by waste.
To clean and clear a blocked drain or blocked manhole like this you will need a high pressure water jetter, the black hose you can see uses the high pressure water to clear the blockage and clean the drain in the process.
In this particular case we jetted the drain for around 20 minutes to clear the blockage downstream and allow all of the waste to pass on. At this point we also proved that all of the waste from the customer toilets was flowing to this manhole.
The cause of the blockage was baby/face wipes were being disposed of down the customer toilets, this is a common problem in drains especially public toilets.
As the wipes snag and accumulate the flow in the drain starts to slow and the solid waste blocks the pipe up until you cannot flush the toilet.
Once every thing has been carefully checked the manhole and the surrounding area was cleaned down (picture right) and the cover resealed to prevent foul smells coming from the drains.
Before we left site we tested the drain and checked that it is free flowing, on this job we carried out a dye test. First we located the closest external foul manhole chamber and opened it up (picture right).
We added some dye to the toilets and flushed them a few times after a few seconds we had our bright green tracing dye come running through the manhole on the outside of the building.