CASE STUDY: HOW IS IT, MY NEW HOME HAS A BLOCKAGE AFTER ONLY 6 MONTHS?
The following case highlights the importance of getting drains checked before handing over the keys to the owners of a new build. It also reminds us that even though there may be damage to pipework it could take several months for a problem to appear.
This damaged sewer pipe was discovered when the owners of this new house noticed the slow draining of all plumbing fixtures in their bathroom.
We were called in to solve the problem, as the clients were baffled that it could be blocked. After all, they had only been living in their dream home for 6 short months.
Upon inspection and clearing of the blockage it was discovered that the 45 degree bend (pictured above) had been hit at some stage during construction, and the inspection cap (like the one in the picture on the right) had been completely ripped off.
Now if you unscrew the cap of these inspection bends then you will see that there is an insert that slides into the fitting. This insert, is made in a way that when inserted into position, it allows the internal diameter of the bend to be smooth and free of edges so paper and other material doesn’t catch.
(Below are a few pictures of a 100mm 45 degree inspection bend with fitting insert.)
In this case you may not be able to see, but the picture at the top of the page on the left where the cap has been snapped off, this still has the bend insert in the fitting. This helped initially when the damage was done because the pipe couldn’t fill with soil, allowing water and paper to still flow through the bend.
However upon inspection with our cctv drain camera you could see on the monitor that the insert for the fitting had been dislodged out of its groove, probably through the impact of the machinery hitting it. This dislodgement created an edge and closed off the diameter of the pipe. This allowed paper to build up behind it as it flowed through the system. Now it could be through sheer luck that a blockage hadn’t occurred earlier, but eventually a clump of paper had hooked itself onto the exposed edges and wasn’t able to be dislodged through water flowing past it. This was the beginning of the end, as paper built up flush after flush.
(The picture below is taken from inside the pipe by our drain camera, showing the fitting insert twisted out of place in the fitting.)
Of course, water is still able to seep through the wall of paper blocked in the pipe but solids are trapped building up over time. You can see the result of this when you flush the blocked toilet, as straight away the bowl fills with water and then slowly subsides after 5 or 10 minutes. This only occurs when the rest of the pipework from the toilet you’re flushing to the damaged pipe is also full of water, leaving the water with nowhere to go but to rise upwards. The distance to the blockage down the line and frequency of use usually depends on the amount of time it’ll take for the pipe to fill with waste water as well.
In this case, the damaged bend was 20 meters away from the bathroom, with no other plumbing connections between the damaged section and bathroom. This could’ve been the cause for an extended period of time before the blockage was noticeable.
So it’s because of these factors the blockage may take some time to visually appear in your bathroom. On this particular occasion, the blockage was located in a grassed area and easily dug up and exposed but on many other occasions this will not be the case and breakages will be under driveways, carports and concrete paths.
So we just advise before a house has concrete poured in driveways, carports or around the house, get the drains checked with a camera, it is a great way to avoid future problems.
CASE STUDY: RESIDENTIAL PROPERTY: WHAT HAPPENS WHEN A HORIZONTAL BORER DRILLS THROUGH A SEWER PIPE?
Called out on a Friday night on behalf of a plumbing company for a blocked drain at a client’s new house. On the left side of the house, the drain was found to be broken. Break was marked on the ground for the plumbing company to repair.
Returned to site 4 days later to flush sand from the line and inspect for further breaks. 1x break located 3.5m upstream of the sewer shaft which the plumbing company repaired. Sewer shaft was blocked and it was believed that a lot of sand had flushed down the line. We jetted the line to clear the sand and once sand had been removed a rag could be seen inside the pipe. We removed the rag and upon further inspection with our camera found that the sewer pipe had been damaged and had an electrical conduit running through it from a horizontal borer. If it wasn’t for our cctv camera and the plumbing company didn’t call us for a camera inspection this may have ended very badly if they decided to put their drain machine with a cutting head down the pipe and try to cut through the blockage.
WHY CONSTRUCTION RUBBLE SHOULDN’T BE PILED UP NEAR SEWER SHAFTS.
Arrived on site to a blocked sewer shaft at a recently finished new residential build. The sewer shaft was in the driveway and I was told by the plumbers that required our services, that the construction rubbish pile was close if not over top of the sewer shaft before it was cleared away.
Pieces of sheet metal stuck at the bottom of the shaft, sand was piled up on top it blocking the shaft.
Removed the bulk of the sheet metal and flushed the line.
Noticed that there was also a blocked rod end to the right of the front door. A broken drain was discovered just under the paved path near the front door.
Breakage was marked on the ground and repaired by other plumbing company.
CASE STUDY: BLOCKAGE AS A RESULT OF CONSTRUCTION RUBBLE
Called out to clear blocked floor waste gully. Gully was inspected inside the bathroom and was clear but the drain had a large amount of concrete stuck between the gully and the footing. No break in the pipe once the concrete was cleared.
Waterproofing appears to be stuck on the bottom of the pipe. Slab repair coupling hard up against footing.
Pieces of concrete.
Jetter clearing the concrete.
Buildup of hair and foreign objects caught at the blockage. Whole pipe blocked with a concrete plug, jetter was used as well as acid to break up concrete. The plug was diameter of pipe and 250mm long.
Pieces of concrete washing out.
5mm gap at the top of pipe was allowing blockage to slowly drain. Pieces of PVC within concrete.
Last piece of concrete now loose in pipe.
Cut the pipe at the footing and dragged the last of the plug out once loose. Drain repaired once concrete is cleared.
Behind concrete plug was construction debris.
Picture of outlet of gully. Camera checked from the footing through to the gully outlet, no breaks were located.
CASE STUDY: ROOT PENETRATION THROUGH PLASTIC INSPECTION CAP
Inspection opening excavated where tree roots were located. Tree roots visible in the inspection point. This section has been cut out and replaced with pvc.
Tree roots growing in rod end of drain. This section has been cut out and replaced.
Clump of tree roots penetrating the plastic inspection cap of drain.
Join down stream of rod end had tree roots growing in it. This section was replaced by pvc. The camera was sent downstream to the septic tank inlet, drains were clear of tree roots from this point to the septic tank.
Clump of tree roots removed from drain.