Operational performance
Water
As shown in the table below, the quality of drinking water supplied by NWL remained excellent in 2008/09.
| North (N) | Target | Performance | |
|---|---|---|---|
| South (S) | 2008/09 | 2008/09 | |
| DWI Mean Zonal Compliance (%) | N | 99.90 | 99.92 |
| S | 99.98 | 99.99 | |
| DWI Operational Performance Index (%) | N | 99.65 | 99.67 |
| S | 99.98 | 99.98 | |
| Distribution Maintenance Index (%) | N | 99.70 | 99.52 |
| S | 99.80 | 99.96 |
Our plan to increase the capacity of Abberton reservoir near Colchester by 58% reached a key milestone, in April 2009, with the granting of planning permission for the reservoir raising, pipelines and pumping stations. This successful conclusion was the culmination of years of extensive work with environmental scientists, lawyers and planners to produce the environmental statement and supporting documentation submitted to the planning authorities. The EA is continuing to prepare the application to vary its licences at Denver and Blackdyke, in Norfolk, which, together with the enhanced transfer facilities and the enlarged reservoir, will secure water supplies for customers in one of the driest areas in the UK.
One of NWL’s key priorities is to continue to reduce the amount of water lost from its networks and the leakage targets agreed with Ofwat have been met despite increases arising from the colder than average winter. The leakage in our southern operating area remains amongst the lowest in the country as it has been for many years. NWL aims to set best practice standards to manage leakage and is playing a leading role in a review of leakage methodologies with the EA and Ofwat.
A large diameter mains cleaning programme, which began in February 2007 and will be complete by 2011, will improve tap water quality to 500,000 customers in south east Northumberland, north Tyneside and the north of Newcastle. This work is progressing well and will make a significant contribution to the planned reduction in customer complaints.
Water resources
Our plan to increase the capacity of Abberton reservoir near Colchester by 58% reached a key milestone, in April 2009, with the granting of planning permission for the reservoir raising, pipelines and pumping stations. This successful conclusion was the culmination of years of extensive work with environmental scientists, lawyers and planners to produce the environmental statement and supporting documentation submitted to the planning authorities. The EA is continuing to prepare the application to vary its licences at Denver and Blackdyke, in Norfolk, which, together with the enhanced transfer facilities and the enlarged reservoir, will secure water supplies for customers in one of the driest areas in the UK.
Our long running water efficiency promotions and good relationship with our customers continue to produce a positive response. This will become even more important in future following the introduction by Ofwat of water efficiency targets for companies.
Metering also has an important role to play in managing the demand for water. For several years we have been installing water meters on change of occupier in properties in the Essex area. This is in addition to the optional metering scheme available to all customers. Around 43% of domestic households in Essex, 56% in Suffolk and over 20% of Northumbrian are now metered.
Although supplies are plentiful in the north east, we believe it is still important to manage the demand for water so that it does not exceed levels that can be supplied in a sustainable way.