Our business is intrinsically linked to the environment as we rely on it for our raw product, water. For this reason we do all we can to ensure there is a clean, resilient and sustainable supply available for current and future water customers whilst ensuring there is enough water available to support the needs of the environment too. Click 'Discover More' to find out more from our Head of Environment, Emma Goddard.


Our people are dedicated to providing you with the best service possible, whether they’re out in the field searching for leaks, managing our operational sites, testing the quality of your water or answering your queries. Each and every person within the business is dedicated to delivering you the safe reliable tap water supply you expect. Click 'Discover more' to find out more from our Head of HR, Sian Jenkins.

Last updated 13-07-23

Event risk index

Monitored by the Drinking Water Inspectorate, this measure focusses on proactively reducing incident risks relating to water quality.

Event Risk Index (ERI) can be influenced by a range of factors including water quality related customer contacts following burst mains, domestic plumbing issues, a failure at a water treatment works and loss of supply.

The incentive looks at how serious each water quality incident was, how we responded, the number of customers impacted and for how long, a score is then given.

Our target for 2022/23 is to reach a score of 0.000 – meaning we aim to have zero incidents across the calendar year.

How have we performed?

During 2022/2023 we scored 285.4. While this represents a deterioration in performance when compared with last year’s score, company performance remains significantly better than the industry average of 833.1.

We saw an overall reduction in the number of reportable events in 2022/23 as a result of water quality issues, due to targeted investment and process optimisation at our treatment works and improved planning and risk assessment approach for our network operations.

While we have improved the speed and effectiveness of our response to water quality events, to reduce both the number of customers impacted and the time to achieve resolution of each event, our score was adversely impacted by a small number of high impact loss of supply events linked to extreme weather experienced throughout the year. Were it not for these events, our score would have been 22.3, against our corporate plan target of 50.

Case Studies

Ardingly Drought

Record-breaking heatwave and drought

The drought and heatwave that affected the south east of England, the country, Europe (and the USA and China) in summer 2022 were exceptional.

Water bottle station

Supply issues across the South East

Water bottle station

Cockhaise Farm

Grant-funded investments to reduce pressure of drought

Grant-funded investments to reduce pressure of drought