A way to detect water on floor

[J-M-L]

@notsolowki

I took 2 pieces of copper tape 4x4 inch. I put a cheap paper towel in between the 2 pieces and soldered a wire to each side. i put 1 drop of water on the corner of the towell and when it got to the copper my meter read 2Mohm. then i completely saturated the towell it read 200k ohm.

yep that works

(something similar mentioned there Using two wires to detect water - making your own water sensor - #5 by Peter_I)