What is Water Metering?

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Water metering is a way to measure water usage. This guide will explore water metering in detail, including why and how it’s used, the common types of metering devices, and the costs, benefits, and problems associated with this measurement of water use. 

Water Metering: A Definition

Water metering involves using a device known as a water meter to measure the volume of water used by a residential or commercial building supplied with public water. Water metering also determines flow at a certain point in the water system. 

It’s the water supplier’s job to take water meter readings, but customers are advised to take regular readings, too, to ensure that their bills are accurate. 

How Water Use is Measured

Water usage is measured in different units depending on the region. 

In the US, the volume of water used is typically measured in cubic feet (ft.3) or US gallons. In most other parts of the world, water usage is measured in cubic meters (m3) or liters.

Water meters have registers, such as dials that look like clock faces. These indicate the amount of water used in a certain measuring unit (e.g. gallons). Some modern meters now use an LCD screen to display water usage.

Types of Water Meters

The most common types of devices used for water metering are velocity water meters, displacement water meters, and electromagnetic meters. 

Velocity Water Meters

Velocity water meters measure the velocity of water flow, which is then converted into volume to achieve a figure of water usage. 

A velocity water meter comes in several different forms: multi-jet, compound, and turbine. 

• Multi-jet meters are typically used in small commercial and residential situations and use several ports that send multiple jets of water into an impeller. The velocity of the water affects the impeller’s rotation speed. 
• Compound water meters are used to accurately measure both very high and low water flow rates. 
• Turbine meters don’t restrict the path of water flow like jet meters, but they’re also less accurate. These meters are commonly used by large commercial businesses and for fire protection. 

Displacement Water Meters

Displacement water meters require water to physically move or “displace” an element that measures the volume of water used. These meters generate accurate results when used with low or moderate flow rates from small commercial or residential buildings. 

Electromagnetic Water Meters

Electromagnetic water meters, or magnetic flow meters, measure water velocity using electromagnetic measuring elements. These types of water meters can typically measure water flow in both directions, and are ideal for measuring raw, untreated water and wastewater.

Costs Associated With Water Metering

There are three main costs associated with water metering:

1. The cost of purchasing and installing water meters.
2. Recurring costs of extracting meter readings and issuing bills based on a customer’s water consumption.
3. The cost of replacing faulty or old water meters.

The upfront costs of metering are low, but the costs of metering over a water meter’s lifespan generally make up the bulk of the cost. However, advanced metering infrastructure and automated meter reading have reduced these regular maintenance and administrative costs over time. 

Prepaid or Postpaid Water Meters

In some cases, a customer will be able to choose whether to pay in advance for their water use, or pay after. Most water meters are postpaid. Prepaid water meters allow customers to buy a certain amount of water “credit” in advance, which is entered onto a card. Customers need to make consistent credit top-ups to enjoy constant access to water.

Is Water Metering Compulsory?

At the moment, water metering in the U.S. is not compulsory on a national level. However, some suppliers encourage consumers to install a water meter in line with the local community’s efforts to conserve water or meet government targets for water usage. In some cases, local utilities may require a meter for connection to public water services.

Additionally, there may be some situations in which a homeowner is required to install a water meter, such as if the homeowner uses a reverse osmosis filtration system, an extra-large bath, or an automatic-filling swimming pool, or if the homeowner lives in a water-stressed area and the government has ordered for water metering in an effort to maintain a secure water supply. 

Pros and Cons of Water Metering

Water Metering Pros

The biggest advantages of water metering are listed below.

• Because most water meters offer volumetric pricing, customers have an incentive to conserve water (and save money in turn).
• The costs of water meter installation and setup are low.
• Water meters are useful in detecting leaks in water supply lines, which helps reduce any water use that does not earn the metering company revenue.
• Metering is ideally suited to households with lower-than-average water usage, who can save money paying per gallon of water rather than paying a flat monthly fee.

Water Metering Cons:

The setbacks of water metering follow.

• Water meters rely on consistent water pressure to be functional, and this is not a given in developing countries.
• Customers would have to pay for all water used (according to the meter reading), even if some of that water was from a leak in their home
• Families with higher-than-average water use will likely end up spending more money on their water if they use a volume-based water meter compared to paying a monthly flat fee
• It is more difficult for customers to prepare for a fluctuating water bill, and customers could end up underestimating their water use and money owed.

Takeaway

Water metering is a common means of accurately measuring commercial and residential water usage. Families and businesses with below-average water use can enjoy the biggest financial savings from installing and using a water meter.

There are several different types of water meters, with different designs and uses. Ultimately, although water metering can be expensive for operators and unpredictable for customers in the long run, the environmentally friendly, leak detection, and water conservation aspects of this method of measuring water use make it worth the investment.