Introduction

Drinking Water 2025 is the annual publication of the Chief Inspector of Drinking Water for England and Wales. It is the 36th report of the work of the Inspectorate and presents the summary information about drinking water quality for the calendar year of 2025. It is published as an interim report and a final summary report, which covers public water supplies, and a single report, which covers private water supplies. This report is the summary of public water supplies for England. The industry dashboard for England 2025 is shown in summary below: 

Figure 1 – Water industry compliance dashboard

Set out in this report are the key facts about the quality of the public water supplies in England, which is served by 24 water companies delivering supplies to 59.74 million consumers.

Key facts

Public supply key factStatistics
Number of water companies 24
Population supplied   59.74
Water supplied (L/day) 14.48bn
Treatment works  989
Service reservoirs  3626
Water supply zones   2111
Length of mains pipe (km) 322.38k
Surface sources   1,184
Groundwater sources   976
Mixed water sources  241
Table 1 – Compilation of data from all water companies

Key facts for private water supplies

Private supply key factStatistics
Population supplied  818,213
Water supplied (M3/day) 330,970 
Number of supplies  34,102
Number of local authorities with private supplies  219
Sources without a risk assessment  3,119
Table 2 – Compilation of data from all local authorities
Map of water companies supply zones in England and Wales.
Figure 2 – Water companies in England and Wales

Inset appointments

Company codeWater supply zonesVolume supplied (l/day) Population supplied 
ALB  2168,0003,000
ALE  1 40,000 500
ESP  391,699,00013,000
ICW  1325,150,00089,568
IWN  21243,924,434318,293
LNW  9913,402,000103,000
MTX  1 74,000454
MUA  13 18,079411
VWP  15,900,00017,292
Total50070,775,513545,518
Table 3 – Key facts about inset appointment companies who supplied data in 2025