Dug up old concrete floor, but whats going on here?

[Roger440]

I decided, in the end, to remove my concrete over plasti fllor to replace with limecrete.

No major issues other than hard work, but under one area was a very dark line that is wet to touch.

Its like its a channel of water, but doesnt really go anywhere, and the soil each side is dry.

Im am a bit perplexed by it, and also unsure if i need to do something about, though quite what im also unsure.

Thoughts???

[Gothichome]

Just a thought, could it be the remains of a tree or vine root that has rotted away under the cement. The moisture is ground moisture collecting in the cavity. With cement over a plastic the moisture had no way of escaping so it rotted out the root, now that it is open the moisture is pooling.

[88v8]

+1 for Gothic.

Or perhaps a prehistoric mole tunnel.

Ivor

[worms]

Or perhaps a prehistoric mole tunnel.

Ivor

or termites!

[a twig]

Or the next outgrowth of LadyArowana’s Japanese knotweed

[LadyArowana]

Or the next outgrowth of LadyArowana’s Japanese knotweed

I don’t have that any more, I imported some 6 inch long orange slugs….

[Roger440]

Well, i managed to lock myself out of the forum. All sorted now.

The weird marks in the soil were in fact water ingress from outside. The foundations are lumps of limestone.

There was a significant gap. Either there was never any motar inbetween or it had long since decayed. Dug it all out and packed it with more lime mortar.

[LadyArowana]

Well, i managed to lock myself out of the forum. All sorted now.

Welcome back!