What type of drains are these?

[Red2414]

Hi all,

I have just purchased a new house and uplifted a few drain covers to find not what I expected.

Its a 1970s house on corner plot with a garage block to rear/side with large courtyard. Next to my house, 3m away, there are 3 manhole covers in a row about 300mm apart, all with large open chambers half full of water, no actual pipes can be seen. It seems therefore to be surface water but I have never seen this type before, is this a holding tank? Assume not soakaway given its near the house.

The front 2 manholes reveal what appears to be a sealed pipe, is this the foul system? Assume that is why it is sealed?

Any help would be appreciated.

Thanks

Stuart

Untitled

• Red2414
• 29 Aug 2014
• 1

Untitled

• Red2414
• 29 Aug 2014
• 1

 

[Hugh Jaleak]

The 3 covers 300mm apart I suspect are for an oil interceptor, to catch any oil/fuel residue from a parking area and prevent it getting into a watercourse.

The sealed system is possibly foul, although quite why it is that sealed externally i am not sure! Those access pipes are usually for internal use, I would imagine it would be awkward to remove the caps working in that small pit, and there would always be the danger of backed up effluent or trapped gases escaping once seal is broken and possibly overcoming anyone in the bottom of the pit!