ᐅ The sewer manhole is flooded.

Hello everyone!
Before I call the construction company again, I would like to ask for your advice.
I have a question about a wastewater shaft, specifically those concrete rings.

At the beginning of this year, we had an electric backflow valve installed in front of our new house.
It is located underground inside two concrete rings. The installation was done professionally.

A few weeks later, these two rings started to become damp on the inside where they overlap.
We were told that this is normal and there is no cause for concern.
Then it rained for several days in a row, and so much water came through that we had to carry it out in buckets.

Over the past few days, in good weather, we left the manhole cover to the shaft open so that the remaining puddle could dry.

Then it rained normally overnight, and the rings were wet again.
Is it really normal and harmless for the rings to get wet after rain?
Should the rings be sealed with some kind of coating inside or outside?
It can’t be that the valve is standing in water after every heavy rain, can it!?
Was something done incorrectly during the installation?

Thanks in advance!

Does the water from the shaft not drain into the municipal sewer system / public wastewater system?

The wastewater flows from the house through the electric backflow valve to the lifting station. The shaft housing the backflow valve is accessible and usually dry.

I haven’t quite understood yet where the water on the shaft with the check valve goes.

It should normally continue flowing into the sewer system, possibly via a pumping station. In any case, there shouldn’t be any water standing in the shaft since it should always drain away, whether the water comes through the concrete rings or through the inlet pipe.

The shaft is intended solely as a location for the check valve and should not collect any water. Wastewater flows through the piping into the sewer system.

mcburns schrieb:
It looks similar to the picture. The flap is located inside the shaft, and rainwater penetrates from outside, flooding the flap.

Hello,

Water is entering the shaft from outside?

I’m not a plumber or concrete specialist, but in my opinion, the individual shaft elements should be sealed and/or connected using well-sealing foam (such as expanding foam) or a similar material, right?

In our inspection shaft, this was definitely done that way.

Best regards,

Dirk