Water sensor

Our basement flooded for the first time in our three-year history with this house. I hauled the wet carpet out and we let things dry. Now before we repair some holes in the floor, I want to install some sensors to let me know just how wet it gets down there and how much of a problem we have.

I found this fantastic recipe for a cheap soil moisture sensor.

I built four of them thinking I would install the best two. Instead, I found a way to improve the design a bit and ended up with four perfectly good sensors.

The problem I ran into was having the sensor fall apart when I try to cut off the plastic straw mold. My plaster of paris was pretty crumbly and it didn't take much abuse for it to come apart. Instead of throwing out the two most damaged sensors, I tried using a paper mold and re-applying plaster of paris. That way if the paper doesn't come off easily, I can just leave it on and let it be part of the sensor, protecting the plaster of paris and still letting moisture through.

But the paper mold came off easily and I was left with a beautiful form that didn't have to suffer the ravages of a knife.

I'm ready to install them in different locations in the soil under the basement before we pour new concrete.

Hopefully after a few more heavy rains, I'll know whether I need to install a water collector to drain away a rising water table from below, or whether I need better drainage on the sides of the house.