Home Truths . A case for water metering

Summer often brings with it water shortage and huge water bills as residents in cities such as Chennai buy supplies from tankers. So, apartment associations want to charge residents on actual usage, rather than on sq ft or number of residents.

Water metering is therefore becoming a popular option. This has advantages, but you must also consider practical issues in installation and costs before you sign up.

Why meter?

The main reason for the popularity of water meters is fairness. You would not think of having one electricity meter for the entire complex and splitting the bill among residents; so why should water be any different?

Two, it reduces consumption. Various informal studies show that water usage falls 25-30 per cent if users pay based on what they use.

Three, with continuous monitoring, water wastages can be easily detected. For example, leaky toilets — a common cause of water loss — can be identified if the meter runs at night. Identifying and fixing it quickly saves water.

Four, you also save on power as water use reduces. For instance, if the water pumped to the overhead tank is less, the power consumption of the motor reduces.

Also, as the sewage water is less, electricity usage for treatment is lowered.

Costs and payback

Water meters come in different models and costs. For most apartments, cold water meter (as opposed to models that can handle hot water) is sufficient. These may be made of plastic or brass; the method of measurement may be mechanical or digital. Your meter cost will vary based on the model and the features.

For instance, mechanical meters are usually inexpensive and may cost about ₹1,000 per unit. Typically, apartments have multiple water inlets, with one for kitchen, one each for two bathrooms. So, you need to install individual meters at each inlet point.

Besides the unit cost, there is also a cost for the plumber and the support to climb and access the water inlets.

However, for individual apartments in a multi-storey building, taking readings manually is not easy as these pipes may be at locations difficult to access. So, opting for digital meters may be a good idea as they enable remote data collection and come with software to take values from multiple devices to give one reading.

There are also dashboards in the apps to check real-time usage and give alerts if issues such as leaks are noticed.

The disadvantage is the cost which is typically much higher — over ₹7,000 per meter, plus ongoing expenses. However, some vendors offer it at a lower upfront payment with a long-term contract.

For example, you only pay less than ₹2,000 upfront and then a monthly fee of ₹60-150 (based on features offered), with a 10-15-year contract.

Some vendors offer digital meters with a feature that lets you shut off water supply from your app in case there are leaks.

The ability to turn off water helps the apartment management also implement water rationing, if needed.

Some caveats

Before signing up for water metering, you need to ask your contractor and vendor for a few things. A basic factor to consider is selecting the right meter size — picking one that is too large may lead to lower accuracy. You must consider the reliability of the meter before buying, as replacement (especially paying for a plumber or technician) can be expensive.

Many mechanical meters have had issues with wrong readings due to intermittent water supply, low water pressure, sudden surges of water pressure, air in the water pipes or wear and tear.

Digital meters are not usually prone to these issues. Sensors have a life time of seven years and the failure rate is less than five per cent. However, with hundreds of units in a complex, you have to plan for issues. Check the warranty, and get life-time performance data of the unit. Also, consider the grade of material (such as plastic) used, to ensure it will not degrade.

Digital meters also require communication, storage and other infrastructure. These may also add to your running costs and possibilities of failure (such as noting down readings when the communication network is down). You must find out how the system works when there is no power and how the vendor will handle maintenance such as replacing a battery in the system.

It is early years of connected devices in India and the risks not very high; but still, be sure to not skimp on security aspects. For instance, can the system be hacked and power shut off maliciously?

The writer is an independent financial consultant

COMMENT NOW