How to Monitor Water Usage
June 30, 2026
Summary: A homeowner’s water use jumped from 2,700 gallons to 34,400 gallons in a single month — all because of a stuck fill valve in a bathroom nobody used. It sounds extreme, but in multifamily buildings, the same thing happens at scale. When residents do not report quietly running toilets and property managers cannot access every suite, leaks go undetected for weeks. Real-time water monitoring gives property owners the visibility to catch these issues before the bill does.
A homeowner recently posted on Reddit after noticing something alarming. Their monthly water use had jumped from 2,700 gallons to 34,400 gallons. No flood. No burst pipe. No obvious disaster. Just a fill valve stuck open in a spare bathroom no one ever used. Running silently for weeks.
The comments flooded in. Plumbers confirmed the math right away. One commenter broke it down simply: 30,000 gallons a month is 1,000 gallons a day, which works out to about 0.7 gallons per minute. Totally credible from a single fixture. Another commenter went even further, noting that at full pressure, a neglected fill valve could produce up to 100,000 gallons of waste in a single month.
That story is striking on its own. But for multifamily property owners, it should feel very familiar. Because that same thing is happening in your building right now and probably more than once.
A homeowner has one toilet in a spare bathroom. You have dozens, maybe hundreds of toilets spread across suites, amenity spaces, and common areas. Some get used every day. Some barely get touched. And without anyone physically walking into each unit, listening for a hiss, checking a tank, or watching a fill valve, there is no way to know what is quietly running.
Across Canadian portfolios that Connected Sensors monitors, about one in three buildings runs over consumption benchmark. Toilets account for roughly 80% of in-suite water waste. Not leaky pipes in the walls. Not irrigation systems running at 3 a.m. Toilets. The fixture everyone assumes is fine because no one hears it and no one sees it.
This is not a crisis you can manage by walking the hallways.
Think about the Reddit homeowner again. The toilet was in a spare bathroom attached to an unused bedroom. Nobody went in there. The fill valve had been spraying for weeks before the water bill finally caught it. Even then, catching it meant a painful bill, not a quick fix.
The homeowner only discovered the problem during a hurried check of the house before work. It was audible when they got close enough. The fill valve was visibly spraying water from the top of the tank. But they had to be standing right there to notice. That is the problem.
In a multifamily building, the dynamic is worse. You are not the one using the suite. Your residents are. And a quietly running toilet does not bother most people enough to call it in. It might not even be audible from the main living area. A fill valve running at a slow trickle is easy to ignore. A resident might notice a faint sound and assume it is normal. They might not even hear it at all.
Meanwhile, the water is running. Every hour. Every day. Every week.
This isn’t theoretical. At North Park Terrace, a 30-unit building managed by York Property Management, Connected Sensors identified multiple toilet leaks during a water audit that had been running continuously day over day before anyone on the management team knew. The leaks were not dramatic. There was no visible flooding, no emergency call, no obvious sign anything was wrong. The monitoring data caught what no walkthrough ever would have.
That is the cost of not knowing.
The Reddit homeowner went from 2,700 gallons to 34,400 gallons in a single month. That is a 31,700-gallon increase. From one toilet. In one bathroom that rarely gets used.
Commenters were quick to point out that while the number sounds almost impossible, the physics are entirely straightforward. At 0.7 gallons per minute, the math adds up fast. And that is a moderate scenario. At full pressure, the number could climb far higher.
To put that in perspective, if just one in five toilets in a 300-unit building lost the same amount as that one Reddit bathroom, the building would waste nearly 1.9 million gallons a month. At Toronto’s 2026 water rates, that could add up to more than $36,000 every month — or over $437,000 a year — from toilets alone.
The Reddit homeowner found the problem because they physically walked into that bathroom and listened. They could hear it. They were in their own home, with access to every room, and it still took a shocking water bill to make them go looking.
You do not have that access in a multifamily building. You cannot walk into a resident’s suite on a Tuesday afternoon to listen for a hissing toilet. And even if you could, a fill valve that cycles irregularly could look perfectly normal when you are standing there.
Water monitoring changes this entirely. Connected Sensors uses the Water Monkey to track building-level flow in real time, identifying consumption patterns that fall outside normal ranges and flagging issues before the next billing cycle tells the story. For toilets specifically, the Water Warden addresses the problem at the fixture itself, automatically regulating water flow and cutting it off when no one is present, while sending real-time alerts the moment a leak is detected.
The point is not to wait for a shocking bill to go looking. It is to have a system that catches a stuck fill valve before it runs for weeks, and in some cases, stops it automatically.
The homeowner got lucky in one sense. The bill arrived, they went looking, and they found a fix that most plumbers said takes about 20 minutes. Simple. Inexpensive. Done.
But they still lost nearly 32,000 gallons before they even knew there was a problem. In a single-family home, that is a rough month. In a multifamily portfolio, that same scenario playing out across multiple suites, multiple buildings, and multiple fixtures is just operating cost you have quietly accepted as normal.
It does not have to be that way. A stuck fill valve is not a catastrophe. It is a fixable problem. The technology to catch it before it runs for weeks, before the bill arrives, before the loss compounds across your portfolio, exists and is working in buildings right now.
One toilet in a spare bathroom sent one homeowner’s water use up by more than 31,000 gallons in a month. The only question worth asking is how many toilets in your building are doing the same thing right now.