How Water Limitation Meters Work


The dreaded WMD (actually a WDM – Water Demand Management System) is here to stay. Many welcome it, others despise it. Whichever way we look at it, physically controlling high water usage is the only way forward. In fact, these devices have been in use since 2006 – initially to assist the indigent. But what do they look like and how do they work?

Simplistically, a WDM is a valve that controls water flow. It allows a pre-set amount of water to flow, and then closes when said amount has been used. The valve opens again at a pre-set time to allow water to flow again -simple. Apart from controlling high water usage, it also prevents water losses due to leaks. In our opinion, its ability to prevent major water leaks is probably its best feature – the media often report on major water losses at private properties, without the occupants being aware of it. A WDM would have prevented that.

Utility Systems is an industry leader in the field of remote communicating electronic water control valves and STS prepayment devices. All Utility Systems products are designed and manufactured in an ISO 9001: 2008 certified facility.

The Water Limitation meter can be programmed with a daily/monthly limit. According to Level 6 Restriction applied by the City of Cape Town it should be set at 350 litres per day (10500 litres per month). This is based on 4 people per household. It will allow you to use 350 litres a day, and then shut off. It will reset again at 04:00 the next morning allowing 350 litres to be used that day. Unused daily allowance will roll over, but the system will reset at the end of the month. At 04:00 on the 1st of every month you will start again and lose any accumulated litres from the previous month. This is to prevent water hoarding, which is NOT the point. It is also important to note that the fact that you have 350 litres per day or 10500 litres per month, does NOT mean you MUST use it all. We should all be conscientious and responsible, and we must try to use less.

Tap-Off now has the ability to re-configure a WMD to be used as a Prepaid Sub-Water Meter with daily/monthly limiting settings. This has a profound impact on the Rental and Sectional Title markets in terms of the ability to recover the water usage from each individual metered area, whilst also limiting the use of water.

Larger households (more than 4 people) can apply for an increase in daily allowance using the forms available on the City’s Website.


Why are there so many complaints about the WDMs?

Installation and maintenance issues: Soil and dirt that enters the system may cause the valve to jam. If the valve jams, the removable battery, which normally lasts 5 to 7 years, will work overtime in its efforts to allow the system to try and open/close the valve. The battery will then run flat in a matter of weeks, causing the WDM to reset to factory settings. This may result in no water at all, until the system is flushed and reconfigured. Dirt can enter the system during installation or when there was a burst pipe in the area. We therefore suggest that a competent and qualified plumber install these devices!

Our own fault: While many of us will remain in denial, quite a lot of perceived problems are self-inflicted. Both devices can be accessed by laptop where usage stats can be retrieved. Some people use their 350 litres and then deny it…. “I did NOT leave the tap open… I did NOT use that much water….”, while the proof is there for all to see. If there is no leak, then you have used the water.

Remember, some geysers have a 200 or 300 Litre capacity. Just to fill that will take almost 80% of your daily allowance. Some top loaders use 190 litres…. etc, etc. Enough said. Regarding geysers, be aware of how much cold water is wasted before the water gets hot. Consider a point of use electric or gas shower head or faucet to reduce water wastage.


How do I read my new WDM?

The Utility Systems WMD’s LCD screen is easy to read and will tell you how much of your allowance is left. The Water limitation device comes with a free wireless keypad when you purchase your meter with Tap-Off. The keypad will allow you to see your daily allocation as well as your remaining daily allocation from inside the comfort of your own home!

What can I do to make living with my WDM easier?

Frequently check for leaks – any leak on your side of the meter will reduce your daily allowance and cause the valve to close. Remember, not all leaks are visible. Some remain undetected for days and even weeks. Make a point to check for leaks at least once a week.

Audit your personal water usage – know proactively how much you use. Manage your allocated amount carefully.

Now you know….