Lowering of groundwater according to soil report - Your experiences?

Hi,
that deployment was really worth it. One question: What amounts of water have accumulated in the end? The initial calculation was 20 l/s, which equals 5 swimming pools per day! Does that much water really come through?

Best regards,

Andreas

We pumped around 7,300m³ of water in 14 days.
But this is partly due to a lower groundwater level than assumed in the calculation and partly because we set the house 10cm higher than planned and in practice we didn’t free the water down to 50cm below the footing but only about 30cm. Additionally, various soil factors, no rain during the 14 days, and more come into play. There are also practical examples where twice as much was pumped as calculated; you just can’t predict that in advance. We registered an extraction volume of 29,500m³.

If only the foundations, for example, are underwater, you can simply concrete them. The concrete displaces the water. Usually, normal submersible pumps can’t manage to pump that out anyway.

Under certain conditions probably feasible, however, this is only economical in exceptional cases since special concrete that is free from segregation is used for that. Pouring normal concrete under water means the fine particles and/or cement paste are washed out and thus the concrete is diluted. This endangers the stability and properties of the concrete. The water-cement ratio for such concrete must also be particularly high. Any structurally sound engineer tries to avoid this. You can certainly ignore a small puddle, but I would not recommend concreting "into the water" to anyone.

Wow!

We pumped around 7,300m³ of water in 14 days.

that's almost 20 swimming pools! Although not Olympic-sized, but only the "small" 25*10 m local swimming pools, but still! I wouldn't have thought such volumes would add up, but we also didn't have to struggle with this issue.

Thanks for the response and good luck with the further construction!

Best regards,

Andreas

Wow! those are almost 20 swimming pools! Although not Olympic-sized, but just the "small" 25*10 m local swimming pools, but still! I wouldn't have thought such quantities would add up, but we didn't have to struggle with this topic either. Thanks for the reply and good luck with the further construction! Best regards, Andreas

Yes, seeing how it just flowed over the sand barrier of the settling basin was quite impressive. I also did not expect the water to flow so quickly underground. But it was amazing how much pressure the water had. You already get an idea of what the waterproof basement will have to withstand later on, ideally for a lifetime of the house. In the end, that's also been 7.3 Olympic swimming pools. :) Many thanks!

We pumped about 7,300m³ of water in 14 days

seven times the burst aquarium in Berlin :oops: and they only took seconds to empty it :rolleyes:. But you did a great job, it definitely makes sense when small and big children play with water