Best Water Leak Alarms for Floods & Emergencies
Water leaks can be nightmarish- especially if they go undetected. Floods can be deadly- especially if they are unexpected. Luckily, there is technology to detect water well before it harms you or your home. There are many types of water alarms out there, but some models are much more effective than others.
This is where we come in. We’ve researched the best water leak alarms, tested them, and now the results are in: the overall best, a starter option, and an upgrade option. If you need a detector that you can trust to alert you to leaks and floods, one of our suggestions will sound the alarm.
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In this latest update of the best water leak alarms, additional pictures have been added, and new selections have been made. When you buy through our links, we may earn a commission. Disclosure»
Best Water Leak Alarm
Govee Detector
Sensitive, Loud, and Versatile
This easy-to-use water detector has the perfect sensitivity for a wide range of applications, at the right price.
*Price at time of publishing; check for price changes or sales.
Govee gives us the most versatile option available, with an inexpensive stand-alone detector that can also be extended into a whole-home WiFi network. The small profile makes them great to nest under water heaters, washers, or in the corner of a basement.
Specifications
- 100 dB alarm (we measured 90 dB at 1 yard)
- Extendable WiFi capability (sold separately)
- 2x AAA battery-powered
The shrill alarm is loud enough to get your attention from anywhere in the house, and it has a silence button on it, making it easy to deal with. It also has a rhythm to it: on for a few seconds, off for a few seconds, which can make it easy to distinguish. You can also adjust the alarm sound lower if you are using it for non-emergencies.
The small light bar on the front turns red when the pins detect water, but it is not going to light up a room- it is simply an indicator light.
With effective detection and versatile notification all in a small profile, it’s easy to see why the Govee Water Detector Alarm tops the rest.
Loudest Water Leak Alarm
The Watchdog
Loud, Simple, and Effective
This simple and proven alarm can set you up to detect water leaks on a budget.
*Price at time of publishing; check for price changes or sales.
Glentronics hasn’t changed its Watchdog over the years, and they haven’t had to. This thing has been protecting basements for over 30 years, and its simplicity is the key.
Specifications
- 1/32″ water sensitivity
- 110 dB alarm (we measured 102 dB at 1 yard)
- Solid-state reliability, extendable 12-gauge wire
- 9V battery powered
With solid-state electronics and a simple wired sensor that can pop off the back and extend 6′, it is the perfect budget solution. It’s also easy to modify- extend the sensor up to 100 feet with standard 24-gauge wire.
One downside is that it isn’t sealed up. The 9V battery compartment is easy to get to, but it can also get wet if the entire unit does. Other water alarms are more waterproof themselves, but the Watchdog relies on the removable sensor plate to get close to the water- hopefully positioning the actual unit to a spot where it won’t get wet.
The alarm sound was the highest pitch we tested, and also the loudest. It is not adjustable and does not pulsate in any way.
If you are looking for an inexpensive but foolproof alarm for your basement, The Watchdog Leak Alarm is the best option.
Remote Water Leak Alarm
SwitchBot WiFi Smart Sensor
Versatile, Smart, and Compact
Get notified anywhere if there is water present with a surprisingly affordable IoT water alarm that integrates with a wide range of services.
*Price at time of publishing; check for price changes or sales.
SwitchBot has developed an intuitive smart sensor that is easy to use while giving great coverage in expandability and notification. Cover essential areas or blanket your whole house by just buying more- no hubs to deal with or device count limits.
Specifications
- Dual detector and 1-meter remote detector
- 100 dB alarm (we measured 91 dB at 1 yard)
- Multi-alert system for notification anywhere (alarm and WiFi)
- 2x AAA battery-powered remote detector
One downside is that the WiFi compatibility is 2.4 GHz only (not 5 GHz), but that isn’t too surprising if you already have IoT devices. It works seamlessly with the SwitchBot ecosystem, or you can run it on third-party services, including Alexa/Google/Siri/IFTTT/SmartThings.
If you want to know when water is present, even if you’re on the go, the SwitchBot WiFi Water Leak Smart Sensor and Alarm is the best choice.
Comparison Table
| Water Leak Alarm | Recommendation | Price* | Loudness | Batteries |
|---|---|---|---|---|
| Govee Detector | Best Overall | $13 | 90 dB | 2x AAA |
| The Watchdog | Best for Loud Alerts | $12 | 102 dB | 9V |
| SwitchBot Smart Sensor | Best for Remote Notification | $20 | 91 dB | 2x AAA |
The Alarms We Compared
Our research narrowed the field down to a few brands and types of alarms that we compared: Govee, Watchdog, D-Link, Moen, Honeywell, Monnit, Alert Labs, First Alert, Flume, and more.
You can see our full list of review criteria below in the What to Look For section, with an explanation for each.
We considered a wide range of alarms with plenty of different models across many different manufacturers. Battery-powered versus AC-powered alarms caused an interesting discussion, and we almost excluded the latter option. But many of our readers smartly have backup power sources for their homes. We ended up including them in our comparison just because the convenience of IoT notification couldn’t be overlooked.
We’re always looking for new and better equipment, so if you have a water alarm you trust, let us know in the comments. We review most of our tested equipment annually, so we can try to get it in the next roundup and see if it will beat out our top picks.
How We Tested Water Alarms
After researching and comparing the best online, we bought several to test them out with practical tests in water. Using a glass bowl to simulate a flooded room, testing the sensors was fairly straightforward.
We used different levels of water to test sensitivity, but quickly found that metal-contact alarms were predictable with their contact height. The alarm user can set them up above the ground for less sensitivity. For alarms with multiple pins, only two needed to be bridged by water for the alarm to sound.
To test the notification of the alarms (their loudness, for most models), we used an app called Decibel X as our decibel meter, which we’ve used previously, measuring the loudness of whistles and other gear.
What to Look For
The best water alarms have a few features to look for:
- Value
- Sensitivity
- Notification
- Power & Reach
- Versatility
When you get the right blend of these, you can find the perfect water detector to find leaks and floods early. Below, we break down what each of these features means for the alarms that truly set themselves apart.
Value: Cost vs. Benefit
The amount of money you spend on something like a water alarm shouldn’t blow out your entire budget. There is a wide range of prices, mostly according to how they are powered and their ability to notify remotely.
You never want to spend too much money on one resource, even when it comes to safety and security equipment. It’s better to diversify your spending to make sure you are covered for a wide range of scenarios.
Sensitivity
Sensitivity goes both ways with water alarms because water vapor is present in the air. Humid summer days, light condensation, and other false positives can drive you crazy if the detection is too sensitive.
On the other hand, if your alarm is not sensitive enough, it may not sound before it is submerged in water and possibly useless. Some models allow you to tune sensitivity, but that is often hard to gauge without water to test it with.
Notification
Most alarms make a lot of noise. The more noise, the better- as long as there is a shut-off feature. Those that don’t have shut-off features need batteries or sensor wires removed to silence the alarm. Having a towel on hand also helped us quiet alarms after testing.
Thanks to technology, Internet of Things (IoT) devices can now notify your smartphone and send messages and emails to notify you when water detection is triggered. With our phones by our sides, this lets you know instantly, regardless of whether you are in earshot. It does rely on significantly more infrastructure, though, making it less ideal for storms and other disasters where the internet, cell service, and power can be interrupted.
Power & Reach
Speaking of power, many of the simple alarms go for battery power. Common batteries, like 9 volts, AA, and AAA batteries, can last a long time in water alarms since the devices do not use much power when they are not sounding the alarm.
You can find hard-wired solutions, but those are less than ideal for storms and emergencies unless you have reliable backup power sources.
Versatility
You can find a lot of uses for devices that make a lot of noise when they get wet. There is a wide range of uses for water alarms. You can make it alarm when it detects a specific amount of accumulating rain, when your rain collection barrels are full, or when a ditch becomes full of water.
Using ice and a little bit of math, you can also make a timer. Your alarm will go off after the ice melts and the water touches the alarm.
You can also use one as an impromptu tripwire alarm. With the ability to detect water and get very loud (or even send notifications), you can get creative in your survival solutions.
How to Use a Leak Alarm
There are a few ways to detect water electronically, but most sensors let water complete a circuit to set off the alarm. Depending on the type, it can sound a 100+ dB audible alarm, turn on a strobe light, or even trigger an IoT event to notify you across the world.
To set up an alarm, you’ll need to first identify the area that you would like to monitor. This can be a basement to check for possible flooding, or at the base of a household appliance to check for leaks.
Next, you’ll power the alarm with AC power or the batteries it specifies. Most battery-powered alarms have a massive battery life of up to 5 years because they are simply waiting for water to complete a circuit.
From there, you can further set up IoT automation and add the water sensor to your inspection rotation. I prefer to check mine on the same interval as my smoke alarms and fire extinguishers.
Who Needs Water Leak Alarms?
Many people with basements and older water-related appliances use water alarms for leak detection, but they can also be very useful for flood notifications and emergencies. They can come in handy for any disaster involving water, including:
- Floods (of course)
- Severe Storms
- Hurricanes
- Tsunamis
Other disasters and events that damage your household could cause leaks, although water damage is usually a lesser concern at that point.
If you find yourself with extras, they are useful to stay vigilant with aging appliances, particularly water heaters and washers.
How We Review Products: We research thoroughly before selecting the best products to review. We have vast prepping and survival experience and bring in outside experts when needed. Hours on end are spent testing gear in stressful conditions and using specialized testing gear to verify claims. We assign performance criteria and impartially rate each tested item. Learn more about how we test.
Sources & References
All of our experience and the testing we do to determine the best water leak alarm are useless without listing our research sources and references. We leaned on these for the book knowledge that we paired with our hands-on testing and practical prepping experience:
Chan, T., et al. (2018). Review of Current Technologies and Proposed Intelligent Methodologies for Water Distributed Network Leakage Detection. IEEE. Volume 6. Pages 78846 – 78867. (Source)
Convey, H., et al. (2002). Development of a Water Leak Detection System. Computing and Control Engineering Journal. Volume 33. Pages 33 – 38. (Source)
Rabeek, S., et al. (2019). Design of Wireless IoT Sensor Node & Platform for Water Pipeline Leak Detection. IEEE Asia-Pacific Microwave Conference (APMC). (Source)
Conclusion
A water alarm can make a difference if you have one at the right place at the right time. Floods can be devastating, and leaks can be a nuisance, so be notified to catch them as early as possible.
Here are a few other gear reviews and guides our subscribers have found helpful:
- Best Flood Barriers for Disasters and Emergencies
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See more of our expert-written guides, resources, and reviews in your search results – add TruePrepper as a preferred source.
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