Reliability and availability

We use a wide variety of other information to assess risks to customers – and decide whether we need to take action on your behalf. This is part of our approach for holding water companies to account.

Below we highlight the overall performance of the monopoly water and sewerage and water only companies in England and Wales in 2012-13 – and any action we are taking to protect customers’ interests.

Reliability and availability indicators

In 2012-13, all but one of the companies met their targets for reducing water leaks from their networks. The level of leakage was still around its lowest level since records began in the early 1990s.

2012-13 was a much wetter year. As a result there were no restrictions in place on water use, as reservoir levels depleted by two drier years were topped up. Overall, companies were able to provide us with reassurance that they were able to supply enough water to meet their customers’ needs. Find out more about why water companies sometimes need to restrict water supplies.

Each company is required to maintain its assets (such as water and sewerage treatment works, and underground networks of water mains and sewers) to a certain standard so that it can provide reliable services to you over the long term ‒ and protect the environment. We call this ‘stable serviceability’.

When a company is not maintaining its assets effectively, there will be a rise in the number of incidents such as burst water mains or sewers overflowing. So it is important they get it right.

Companies have told us that overall they maintained their assets to a sufficient standard in 2012-13.

Action we are taking

Portsmouth Water failed to meet their leakage target in 2012-13. In 2012 the company also found that it had failed over a consecutive number of years in the past.

We have ensured that Portsmouth is taking action to rectify its mistakes, which will see it reduce leakage to its lowest ever level by 2015. Portsmouth has committed to spend an extra £1 million on fixing their failure, at no extra cost to their customers. We will check this happens.

Companies that had less than stable (‘marginal’) serviceability are seeking to restore assets to stable serviceability. We will review their progress with these action plans as part of the 2014 price review. This includes clawing back money for customers where companies have not restored their performance.

Data

We have collated below the performance data companies have published.

	Serviceability water non-infrastructure	Serviceability water infrastructure	Serviceability for sewerage non-infrastructure	Serviceability sewerage infrastructure	Leakage	Security of supply index (SoSI)
Anglian	STABLE	STABLE	STABLE	MARGINAL	189.00	100
Dŵr Cymru	STABLE	STABLE	STABLE	STABLE	184.80	100
Northumbrian	STABLE	STABLE	STABLE	STABLE	136.00	100
Northumbrian (Essex & Suffolk)					53.90	97
Severn Trent	STABLE	STABLE	STABLE	STABLE	441.00	100
South West	STABLE	STABLE	STABLE	STABLE	84.20	100
Southern	STABLE	STABLE	MARGINAL	STABLE	81.00	100
Thames	STABLE	STABLE	STABLE	MARGINAL	646.00	100
United Utilities	STABLE	STABLE	IMPROVING	STABLE	457.00	100
Wessex	STABLE	STABLE	STABLE	STABLE	69.00	100
Yorkshire	STABLE	STABLE	STABLE	STABLE	265.00	100
Affinity Water
– Central area	STABLE	STABLE	—	—	178.00	100
– East area	STABLE	STABLE	—	—	4.20	100
– Southeast area	STABLE	STABLE	—	—	7.10	100
Bristol	STABLE	STABLE	—	—	42.00	100
Dee Valley	STABLE	MARGINAL	—	—	9.28	100
Portsmouth	STABLE	STABLE	—	—	34.07	100
Sembcorp Bournemouth	STABLE	STABLE	—	—	20.90	100
South East	STABLE	STABLE	—	—	93.16	100
South Staffs	STABLE	STABLE	—	—	65.30	100
South Staffs (Cambridge)	STABLE	STABLE	—	—	12.40	100
Sutton & East Surrey	STABLE	STABLE	—	—	23.70	100

Green means the company’s performance is in line with or better than expected
Amber means the company’s performance is not in line with expectations but performance has slipped only slightly
Red means the company’s performance is significantly below target or expectation
Blue means companies did not have to submit this data