Article (55) Section (3) refers to the general function of the Bureau which is "the establishment, maintenance, review and amendment as appropriate of technical and performance standards for the water and electricity sector and the monitoring and enforcement of compliance with such technical standards". In addition Article (54) Section (4) refers to the general duty of the Bureau is to "Publish information relating to standards of performance by licensed operators."
1- Water Distribution System Key Performance Indicators
The Bureau developed, in consultation with the Distribution Companies, three technical performance indicators (KPI’s): "Interruption to Supply", "Pressure of Supply", and "Type of Supply". Another KPI, relating to the quality of the water distributed, has been developed as part of the Water Quality Regulations and compliance with sampling and prescribed limits is measured by Bureau.
While developing the KPI’s, the Bureau was interested in understanding the level of performance within the sector. As the sector has developed and the Bureau gained a clearer understanding of the licensees’ performance capability, other amendments have been made to existing KPI’s. In 2004 and after consultation with the Distribution Companies, the Bureau introduced a new KPI (metering), made modifications to the existing KPI’s and set targets that define the performance expectations of network companies.
I - Meter Installation
The meter installation KPI is divided into the following three meter classifications:
I.1 Number of Customer Meters Installed
Increasing the level of customer metering potentially provides more revenue for the Network Companies and also provides key management information for the planning and operation functions of the distribution businesses.
This component of the metering KPI is defined as the number of meters installed for revenue purposes to customers per month.
The water meter is normally installed at the end of the customer’s service connection or installed within the customer’s internal water network. This KPI will provide the Bureau with an ability to focus on the number of customers who have their water usage metered and monitored. It is proposed that the KPI will be further subdivided into customer class (domestic, commercial, industrial and agricultural).
I.2 Number of Transmission Interface Meters Installed
Interface meter readings provide critical data to the settlement process between Network Companies.
The data from water meters at the interface points will help the Bureau and the Network Companies understand the losses in the transmission system and the distribution network, as well as accurately quantifying the actual water quantities received by the Distribution Companies from TRANSCO.
I.3 Number of Zone Meters Installed
Zone and District Metering are important in the assessment of system losses and as monitoring tools for planning and demand management processes. They allow the collection of water usage information from key areas or zones within the water networks. The Bureau’s Water System Management Project also identified zone monitoring of water usage as a “world’s best practice” type approach, particularly for leakage monitoring and in introducing water demand management initiatives.
The Bureau originally set 0.5 Bar as the minimum pressure in the distribution network to allow sufficient pressure to supply customers’ ground tanks. Over the past 3 years compliance with this performance standard by the Distribution Companies has improved to almost 100% in all locations tested. The Bureau has now increased this minimum pressure target from 0.5 Bar to 1.25 Bar in all the areas serviced by the Distribution Companies. Compliance to this pressure level will require some improvement in both the transmission and distribution systems.
The Bureau’s aim in increasing the minimum pressure standard in the distribution network is two-fold. Firstly it should ensure that no infiltration or ingress of ground contaminants into the water network. And secondly it should reduce reliance on ground storage tanks, as sufficient pressure would be available to supply low rise buildings directly. This approach of raising the distribution system’s minimum pressure level also aligns with "international good practice".
III- Method of Water Supply
Customers are generally supplied via a piped network, however, some customers are supplied by water tankers. The purpose of this KPI is to obtain monthly information on the number of customers supplied by tankers and the piped network (intermittent and continuous supply).
IV- Interruption of Supply
Companies are required to report the number of bursts, equipment failure, etc. and are expected to maintain a register of interruptions so as to identify the number of properties affected. All interruptions over a minimum duration of 6 hours, along with the number of properties that are affected, are required to be reported. The indicator will show the number of properties experiencing interruptions to their supply for more than 6 hours, 12 hours and 24 hours, together with an estimate of the volume of water not supplied.
2- Water Transmission System Key Performance Indicators
The Bureau, in consultation with TRANSCO, identified and developed three technical key performance indicators: unaccounted for water, availability of the transmission system and security of supply.
These indicators are believed to be the key ones at the current stage, and the Bureau will continue to investigate if further modifications are required to improve them.
I- UNACCOUNTED FOR WATER
The net difference between the water dispatched from all the water producers at the defined entry points to the transmission system and the water delivered at the distribution exit points is defined as unaccounted for water.
The unaccounted for water at the transmission system is mainly due to real and apparent losses. Real losses are the losses caused by physical leakage from the network. Apparent losses are the losses that are unmeasured (un-metered), errors in metering and illegal connections.
On a daily basis TRANSCO is required to produce a balance sheet which shows the total monthly inflow to the transmission system from all the water producers including the change in the storage at the relevant regional transmission system. Then, the total inflow and the difference in storage are subtracted from total outflow at all the connection points between TRANSCO and the Distribution Companies. This results in a figure for the total unaccounted for water.
Planned work is required to accommodate new user connections, essential asset replacement, as well as the maintenance necessary to retain a high level of system reliability to ensure security of supply. Annual system availability, which is primarily influenced by planned and unplanned outages, can be calculated.
Water Transmission System components that are either operational or on stand-by mode are considered to be available. Otherwise they are unavailable.
The availability will be reduced whenever a component from the transmission system is taken out of operation either for planned or unplanned purposes. A component is defined as a pump, water transmission line, storage tank, surge vessel or a combination of these plant items.
Planned un-availability can be due to the following:
III- SECURITY OF SUPPLY
- Maintenance outage: an outage required for all types of planned (week or more) maintenance jobs.
- System construction outage: an outage required to construct or modify assets, which are not provided for the benefit of the users.
- User connection outage: an outage required to construct or modify assets, which are provided to facilitate connection for the benefit of the system user.
- Unplanned un-availability is due to either a forced outage or an outage which occurred as a result of component breakdown.
- TRANSCO reports monthly overall availability and the availability against the three types of planned outages mentioned above. This will enable the Bureau and TRANSCO to monitor the difference between these types of planned outages.
The purpose of monitoring this indicator is to understand the level of system security in relation to scheduling and dispatch functions
The security of supply is the total unsupplied water that was committed to be dispatched at the interface connection points according to the daily water scheduling in the Water Transmission Code. However, due to over or under estimation by Distribution Companies or incidents on the Transmission system, agreed dispatched quantities were not delivered.
Since the current supply arrangement is of an intermittent type in some of the areas, it will be an important indictor to monitor TRANSCO’s system security of supply compliance.
The Security of Supply Indicator reports; the number of events where daily demand forecasts were above or under 20 % of the agreed demand quantities; transmission system incidents and the total unsupplied water quantities (MIG) to the distribution system at the interface connection points between TRANSCO and Distribution Companies.