Metering water supply from source to consumers is the only way forward to stop water wastage: what is not measured cannot be managed! Once the network is equipped with a permanent monitoring system it will be possible to improve the level of service identifying both real and apparent losses, establishing an equitable distribution of the resource, providing a fair way to allocate costs, and promoting water conservation.
Before reaching consumers, water flows from the abstraction point to the treatment plants and beyond, up to storage reservoirs and the distribution network. By monitoring the flow along such path, suppliers can get the knowledge of the amount that is being distributed and the amount that is lost in each part of the system, which is essential to guarantee an equitable distribution of water.
The installation of a detailed monitoring system is to be done at Pumping Stations in order to control the flow that is injected in the system, the pump efficiency and the energy consumption. Also reservoirs should be controlled by installing level meters to avoid the unfortunately frequent wastage of water through overflows.
Metering is then used to find out how much water is being extracted from the system and to bill customers according to their actual consumptions, which is perceived by many as the fairest way to allocate the costs of water supply to users.
When people pay for the amount they use, water conservation is encouraged: there is evidence from the UK that there is an instant 10% drop in consumption when meters are being installed; in Hamburg (Germany) domestic daily water consumption for metered apartments (112 liter per capita) was 18% lower than for unmetered ones (137 liter per capita); and so on. Water conservation automatically leads to a reduction in costs, both in the short run (by reducing operating costs) and in the long run (by postponing costly system expansions).
Also portable equipment can be used for short term monitoring of flow and pressure in key points of the network. This activity is very important to support network model calibration, DMA (District Metered Area) design and implementation, and pressure management.
Modern technologies allow to establish a remote control system able to receive data on a central computer from each bulk meter or pressure logger installed on the field by using GPRS protocol. Also users’ meters can be read automatically if an AMR (Automatic Meter Reading) system is installed.
To cut a long story short: monitoring is essential to start thinking the water supply system as an “industry” to be optimised in each step of the process: production, storage and distribution.
UNIVERSAL METERING OF WATER SUPPLIES
Any resource supplied without measuring the quantity of supply has chances of being wasted. The quantity supplied is not known and hence quantity wasted is also not known. Charging for any resource on the surrogate measurement or indirectly do not motivate the consumers to use the resource judiciously. Same is true for water also. It is essential to supply water duly measured and charge for the quantity supplied. This reduces wastage and also undue consumption.
The metering efforts of water is traditionally opposed due to fears that it will lead to more bill for water and second being the human errors involved in meter reading will add to sufferings of consumers.
Answer lies in the fact that in flat rates for water, one who uses less water also pays the same amount as of the one who uses more. In turn the poor who uses less, subsidise the others who use more. The answer to human errors is now available in technology. The Automated Meter Reading type meters avoids the human errors in reading the meters and handling the data.
Another facts faced in the past by the consumers is meter going out of order very frequently and then average bills etc followed by meter repairing and testing etc made life miserable.
Earlier it used to be wet type meters in which there were train of gears which used to register the flow of water measured by rotating turbine. These gears used to go out of order frequently. Now in the dry dial type of meters the register is completely dry using magnetic transmission of motion of turbine to register. The earlier A - Class meters are now replaced by minimum B- class meters with 2% accuracy.
The air coming before the water gets registered as the meter rotates because of air is one more genuine reason for opposing fixing of meters.
This reason is valid for the consumers which live in higher areas and the distribution pipeline ascend from lower area to higher areas. The intermittent water supply systems have this problem for such areas predominantly. Now the air release valves are available which when installed earlier to the meter do not allow air to pass through the meter and completely expels it out.
One more reason for the opposition to water meter is after passage of some years when the strainer ahead of meters get loaded with dirt etc and due to heavy head loss across it, the consumer get less water.
This is a maintenance problem and the strainer shall be cleaned periodically. The Municipal corporation shall have a periodic maintenance protocol established and act on that. It shall also include calibration of meters at fixed intervals.
Cities which are going for universal metering
The cities going for universal metering are:
- Mumbai (AMR) in part area
- Navi Mumbai (AMR)
- New Delhi
The towns / cities / villages which already have universal metering are:
- Malkapur (AMR)
- Ambernath and Badlapur
- Hubali Dharwad (part)
- Satara (Area under MJP)