The decision to invest in high-quality water meters, which are specifically designed and improved for South African water conditions, can significantly reduce nonrevenue water consumption and increase an authority’s revenue.

According to meter manufacturer Elster Kent Metering MD Mark Shamley, water losses in the distribution system can be categorised into two types – the losses from actual leakage or the apparent commercial losses that are often the result of inaccuracies in metering, meter reading errors or even billing errors.

These losses can have a negative impact on a municipality’s revenue, while apparent water losses can be easily reduced by choosing the best-performing meter that is suited for the specific local water conditions.

Most domestic meters in South Africa are mechanical devices and performance decreases as a result of the volume and the quality of the water flowing through the meter and the suspended solids (grit) in the water supply.

These factors cause the meter to under-read and, hence, the consumer pays a lower amount than the actual amount due according to the amount of water that has passed through the meter.

“Some meters are designed for the harsh water conditions in South Africa and throughout Africa and, hence, they perform better by coping better with the suspended solids in local circumstances. The meters, therefore, degrade at a slower pace than many of the imported meters.

“It is not wise to buy the cheapest meters, as this could cost a municipality more in revenue than was saved initially over the meters’ life cycle. It’s not the cost of the meter, but the cost of metering that’s important, which ultimately takes into consideration the cost of lost revenue, owing to a meter underreading” says Shamley.

He explains that meters are tested in ideal conditions and clean water is used. Elster Kent meters are designed for use in South African and African water conditions, unlike many of the imported meters.

Meters in South Africa are typically installed for 20 to 30 years, but as a result of local water conditions, the optimal meter replacement period is probably every eight to ten years, depending on the household’s water consumption, the quality of the water passing through it and the quality of the water meter.

The Elster Kent KSM volumetric meters are a good example of a high-quality revenue meter that caters to African water conditions. The unit provides optimum accuracy and performance at all times, even at the lowest flow rate. The meter can be installed in any position – horizontally, vertically, or inclined on pipelines, maintaining optimum performance with no loss of accuracy.

The Elster Kent low-revving piston pro-vides a long working life, substantially reduced meter stoppages and enhanced dura-bility and performance, as a result of the design of the grooved piston within the meter measuring chamber. The action of the grooved piston, with the stationary chamber wall, creates flow eddies that hold solids in suspen-sion until flushed out, thus reducing meter stoppages.

The gear train of the unit is mounted in a gearbox to maintain optimum alignment of the gear and reduce friction. The compen-sating ramp is a new way of allowing move- ment in the plastic body where there are pres-sure shocks. Other meters do not generally compensate for this movement, leading to malalignment of the gear train.