Water leak detector (Life Hack)
This is instructions on how to turn a cheap smoke detector into a water leak detector. I do not have picture of my setup but I did find this video which shows the setup pretty well. https://www.youtube.com/watch?v=Umkw15FETno . Next time I visit the grandparents I will take a picture and add it here.
The basic concept is to take advantage of two things. 1) each smoke detector has a button you push to test that it works. 2) water works well, especially over short distances as a conductor of electricity. As the video shows you take two wires and solder them to the two connectors for the smoke detector test button. At the other end you keep the wires close together but not touching. You will secure these where you expect water to collect.
In my case I put the wires close together inside the crock in the basement. In order to determine where to put them, just watch how full the crock gets before pumping and put the wires just above that line. Within minutes of the pump failing the water will rise up and connect the wires creating a circuit. This will make the smoke detector test button trigger and the alarm will sound. For our grandparents house their crock is hidden under the stairs in the basement and so we ran the wire to the upstairs. The smoke detector is mounted upstairs. When their pump fails it triggers the smoke alarm. They have told me this has saved them several times from flooding. The great thing is that the smoke detector has a battery and so when the power goes out and the sump pump stops working it will still go off. If you do not have a sump pump maybe your sewer drains back up. In this case put the wires close together inside the drain. If water starts to come up or if a leak in the basement runs to this drain your alarm will go off.
Now this is only one use for this type of alarm. It can be setup anywhere water could leak. If you feel like spending more money you can get a wifi sensor and have it notify you if there is a leak. Of course if you power goes out wifi will also not work. As you can see here, sometimes the simplest solution is best.