There are many water spill or flood detectors on the market; some hard wired, some battery operated, some free standing, some tied to central alarm systems. The battery operated models are quite mobile and good for seasonal tasks like spring flooding or specific tasks like the bathtub overflowing. The hard wired ones are always on standby in the basement for plumbing leaks, sewage back-up or foundation leaks.
PROBLEMS
The problem with battery systems in forgotten places is they may just die. Most will give off “weak battery” beeps like smoke alarms, but if ignored will simply die. Hardwired ones never run out of power but tend to be untended for such long periods of time that the contacts can get corroded or coated so that they don’t work when the water comes.
All that to say – choose your alarm well and schedule annual maintenance.
THE BATHTUB -- HIGH LEVEL WATER ALARM
Many years ago I ran across one speciality battery operated alarm that was sold for multiple uses but the inventor confessed to me it was really designed for preventing bathtub overflow. He made the sensor wire out of a cable similar to the old TV antenna wires so that you could bend it to any shape – a special feature that allows it to drop over an edge into a bathtub, a hot-tub or even a swimming pool to tell you when you have arrived at the proper fill level. I was fascinated in talking to him to learn that the most difficult part of the invention was the exact proper shape of the end of the sensor, so it would properly detect the water level.
Above you will see a video that I shot recently to really show this, the most useful water alarm I have ever used – actually one that is used every time that my wife takes a bath. First I wet my finger as you see in the video to make sure the battery is strong. Then we drop it over the edge, turn on the water and simply walk away. It will call us back in plenty of time to turn off the water.
YES – I RECOMMEND THIS DEVICE HIGHLY
Unfortunately it is a bit difficult to buy, although not expensive. It is listed in Home Hardware as the "9Volt High Level Water Alarm" made by Rialco, but not often stocked on the shelves, something that Home Hardware should correct because every bathtub in the country should have one – although you can always special order it. There are other high water level alarms, but none that I have seen that have such an easy and reliable depth setting -- just bend the wire over the edge to where you want the alarm to sound.
Yes, this is one of those few products that I use constantly and for a long time now. Check out the video above. And may I say -- one of those special gift items – a gift that raises eyebrows when someone opens it and then a week later you will receive a phone call offering to wash your feet in their bathtub as they realize that anticipation and panic has gone out of the task of drawing a bath.