Identify this?

[luisdesign]

So a picture landed in my inbox the other day? Im referring specifically to the looped drain. Does anyone have any ideas?



This is in the lower ground floor of an old building (1800s). Its new though, of course, the other side of the breeze wall is a small kitchenette with sink (waste seems to connect directly to a separate manhole there) and a WC which also has direct connection waste. As mentioned, there is another manhole just the other side of the wall, but neither this access chamber seen here nor that other one could be lifted by the person there at the time.

The loop seems to rise above the overflow level of the sink which might suggest its connected for some reason. You can just about see a rodding eye on the far loop...

Imagine the picture turned 90degree clockwise... 'cos apparently I'm not able to flip this now it's been uploaded.

I don't remember coming across this before? Any drainage experts able to shed some more light?

 

[stardanny]

By the look of steel manhole cover on it hinges and power supply control I seen before, possible a pumping station for sewer or well?

The loop is there to stop water back flowing when pump stop.

Can you open the steel cover and see what it is?

Daniel.

 

[Hugh Jaleak]

I'd second Daniel, I see a lot of drainage wells, (albeit on a much larger scale!), working for a Water Company. Went to one a few days ago, with 3 large pumps, and the outlets from all 3 rose up almost to the ceiling before dropping back again to common into the pumping main, although it is not a common design from my experience.

Quite what the theory is behind it though I am unsure, because it that instance the highest point of the loop would still be well below the level of the discharge point, looking at ground levels, location of the well and the delivery point for the pumped effluent. These pumps are often extremely powerful, some being required to push the effluent several miles to the discharge point, and can weigh over a tonne, gravity is hardly likely to play too large a part I would imagine!

 

[luisdesign]

Thanks for the reply chaps.

That seems like a reasonable assumption to me. Theres clearly an electrical cable disappearing into the concrete which is certainly not the incoming mains.

I've said to the chap on site that he really needs to get that hatch up. It does look far too large for a normal manhole.

It's still strange. I mean, yes, the building is at lower ground level, with this being right by the street, which would certainly support a principle of pumped waste except for the fact that the building is very old, and the floor level is not new so at some point in time, and for some reason, there was need for a pumping solution!?

Could be damp, but no treatment on the walls to support that... maybe the small kitchen and WC on the other side of the wall were added to the tail or head of the system and needed extra help to get it working up to the invert level!?

If it's just a rising vent for overflow then I imagine that it can generally be re-positioned to suit which would help. Quite how such an overflow would alert people that a pump has gone is beyond me though... wouldn't it still rely on backing out to an entry point before someone actually noticed!??

Thanks again!