Thread: Drainage Problem - Can You Help?

A pit might work but it is probably better to fit a lockable cover over the end of the pipe so it can be removed during work hours and locked up when unattended

Don't know what the outside access and clearance of the drain pipe is like, but sounds like you need something akin to the trap they put on downpipes going to watertanks to bypass the first flush of water so the leaves and debris don't get to the tank.

Alternatively, you could put in one or more 'T' pieces (depending upon the volume of concrete the little darlings are likely to play with) with the bottom of the T being a blanked off length of pipe aiming downwards with a screw off cap. The heavier concrete bits fall to the bottom as the water flows through, with the cap unscrewed to clean out. Similar concept to the old fashioned glass bowl fuel filters with inlet and outlet on either side. Cheers, Ron

A bit of clarification, please.

1. How much concrete?
2. Is the concrete still wet? If hardened after placement, I don't see how a plumber's snake could break it up; would likely need something more heroic.
3. What is your relationship with the students? Do you have enough authority to really "discourage" this sort of thing, and thereby teach them some self-discipline?
4. Where are the drain and pipe trap? Is it a floor drain, with the trap embedded underground?

Assuming the worst:

If the drain is from a sink, replace the sink with something like a "plaster sink." Such a sink has a sump to receive wet plaster, and an overflow to carry away the water. Not entirely unlike a grease trap, at least in concept. A rubber or plastic liner would facilitate removal of hardened concrete.

If the drain is in the floor, you'd probably need to do some excavation and re-plumbing. A sink, similar to the previous suggestion, in the outdoor pipe. But I think you'd need to remove the trap under the floor drain, and pipe directly to the outdoor sink; otherwise, concrete could accumulate in the first trap. Still need a pipe trap beyond the sink.

Joe

Things have certainly changed since I went to school, I would have in detension for two years