In its first quarterly report of the financial year Water UK found that, since the first report was published in July 2015, overall levels of service performance have risen from 89 per cent to 98 per cent for water supply and from 94 per cent to 99 per cent for sewerage.
Portsmouth Water topped the list for water services in Q1 (April to June) 2016/17, achieving a scoring of 100 per cent. Sutton and East Surrey Water came a close second, with a score of 99.83 per cent, followed by Southern Water (99.77 per cent), Welsh Water (99.66 per cent) and Dee Valley Water (99.43 per cent).
Affinity Water came bottom of the table with a score of 94.71 per cent. However, this was a large improvement on the 91.6 per cent scored the previous quarter, and a dramatic improvement since Q1 2015/16, when the company scored 42 per cent.
Meanwhile, Northumbrian Water scored highest (100 per cent) for sewerage, closely followed by Yorkshire Water (99.93 per cent) and Welsh Water (99.89 per cent).
The lowest scorer was Anglian Water with 94.64 per cent, a slight improvement on the previous quarter.
Water UK chief executive Michael Roberts said: “The latest results on developer services are promising. Water companies continue to be committed to working hard to improve their performance.”
This quarter, Water UK has made changes to the reporting system to provide additional data to “help interpret the performance information” and “better understand the impact of issues”.
The group said that as the year progresses further changes will be made, in response to comments from a range of stakeholders.