Our performance 2014/15

We measure our performance against a wide range of Key Performance Indicators (KPIs), to make sure we are best serving our customers, investors and the environment.

All key business areas are assessed, from customer service to water quality, leakage prevention to financial performance. Results are monitored by the industry's water regulator, Ofwat, and shared with our customers, stakeholders and other regulators.

Our 2014/15 figures make encouraging reading and show how we have continued to improve our performance. Each measure is graded using a traffic light system, with green indicating that we are performing well or a target has been met.

Simply click on the arrows on the left of the headings below to reveal more in depth information.

Customer experience

Customer satisfaction (SIM)


Customers enjoyed a positive experience when dealing with United Utilities in 2014/15 – our Customer Experience Programme is delivering a range of initiatives and improvements that our customers want and our continued progress is encouraging.

In 2014 Ofwat introduced a new Service Incentive Mechanism or SIM measure focused solely on Domestic customers which will be used to measure and compare companies performance from 2015 – 2020. The design of the SIM measure is different than its predecessor, with a greater weighting towards the customer survey (qualitative) element of the overall score and changes to the makeup of the quantitative component.

We trialed the updated SIM during 2014/15 and we have reported our performance based upon Ofwat’s new SIM reporting guidance. Although direct comparisons with prior years SIM scores are not appropriate due to the changes to the score calculation mechanism and the underlying reporting requirements, our SIM score of 81 out of 100 shows our continued progress delivering improved customer satisfaction. Overall complaints reduced by 18% compared to the previous year whilst our 2014/15 average qualitative score was 4.24 points.

Sewer flooding incidents


Internal flooding at properties can occur when sewers become blocked, damaged or overwhelmed during heavy rainstorms. Sewer flooding is a messy and upsetting problem, we are working hard to address this issue in our region.

We recorded a decrease in the number of homes affected by sewer flooding in 2014/15 and we have plans in place to continue bringing the number of internal flooding incidents down.

We have continued to invest in schemes designed to mitigate the risk of flooding at our customers’ homes, including targeting areas more likely to experience flooding and through defect identification using CCTV sewer surveys. Our sewer network will continue to benefit from significant investment going forward as we adapt to weather patterns likely to result from climate change.

Our Think before you flush and pour campaign will help bring the numbers down

Water supply interruptions

13 mins

Our customers rightly expect water on tap, 24/7. We are always striving to reduce interruptions from bursts, scheduled work or accidental damage to pipes.

The average length of interruption per property was just over 13 minutes in 2014/15. To maintain our good performance we are working to improve our ability to recognise and respond to network issues and through the use of our Alternative Supply Vehicles during bursts, we are able to reduce the impact to customers of water supply interruptions.

Water quality


We take pride in every drop of tap water we provide for our customers. In the 2014 calendar year, the water we piped to homes achieved a score of 99.95% for the Drinking Water Inspectorate's measure ‘Mean Zonal Compliance’ - meaning it complies with strict national guidelines for safety and purity. Performance is assessed against 39 individual water quality parameters in samples taken from our customers’ taps.

You can discover more about the region’s drinking water quality here.

Reliability and availability

Looking after the region’s water pipes


We have around 43,000 kilometres of public water mains in the North West. They are monitored around the clock to keep supplies flowing smoothly. Our stewardship of the network is measured against a range of criteria, including number of pipe bursts and number of properties affected by low water pressure or unplanned interruptions to supply.

In 2014/15, we achieved an ‘improving’ rating – which means that overall, we are out-performing our targets.

Managing water treatment works and reservoirs


We have 93 water treatment works and 178 reservoirs in the region. These sites require a rolling programme of maintenance and inspection, to ensure customers receive safe, clean water supplies, and that operations are not harmful to the environment. We achieved a ‘stable’ rating for these sites in 2014/15 - meeting our performance targets.

Looking after the sewer network


Our vast sewer network comprises almost 77,000 km of pipes. Collapses and blockages on the pipes can result in pollution, flooding or disruption to households – so continuous careful management is vital.

In 2014/15, our overall performance was rated as ‘stable’. The number of collapses, blockages and equipment failures recorded on our network has reduced significantly over the last five years and flooding at properties as a result of these sewer related problems reduced for a fifth consecutive year. The number of sewer network pollution incidents also fell in 2014 so overall we achieved a ‘stable’ rating.

Maintaining our sewage treatment works


Our sewage works treat an estimated 2,000 megalitres of wastewater from households and industry every day, before returning it safely to the environment. These works have to conform to strict environmental and operational standards. In 2014/15, the management and maintenance of these sites showed general improvement and exceeded the performance targets for the seventh consecutive year.

Tackling leakage

454 MI/day

We’re working hard to control leakage on our network. Measures including active pressure management, a public leakline number, teams of specialist leakage engineers, and a rolling programme to replace ageing pipes, helped us to exceed our leakage target in 2014/15. This is the ninth consecutive year we've met or exceeded the annual target.

Our leakage target is set to ensure we operate and maintain our water network at the most sustainable economic level. Ofwat monitor our performance against this target. We lost an average of 454 megalitres of water per day, compared to the 2014/15 target of 463 megalitres per day.

Security of supply

100 index score

Ensuring water is always on tap requires careful management of regional supplies. Changing weather patterns, including drier, hotter spells with higher risk of drought, means our strategies for storing and distributing water must adapt accordingly.

By continuing to invest in an integrated, highly adaptable regional water network, and making contingency plans for the future, we kept customers supplied during 2014/15 and achieved a green rating for security of supply.

Reservoir levels


Total storage in our reservoirs at the end of the 2014/15 financial year was above average at 96%.Our latest reservoir level figures can be found here

Environmental impact

Greenhouse gas emissions

474 ktCO2e

An efficient water and wastewater service needn’t cost the earth. Emissions for 2014/15 totaled 473,708 tonnes of carbon dioxide equivalent. This year our carbon emissions are 19% below our 2006 baseline so narrowly missing our short term target of 21% below our baseline in 2015.

Missing this target is extremely disappointing as we purchased less electricity than in any of the last 10 years and generated our highest ever amount of renewable energy. However, we could not counteract the impact of the 11 per cent increase in the carbon content of the UK’s electricity supply. We have achieved a green rating for this measure as performance remained within 10% of our projected target.

More details on our wide ranging environmental activities can be found here.

Sewerage pollution incidents


Pollution incidents can arise when there are problems on our network (e.g. a pipe collapse leading to a sewer spillage) or operational issues at our treatment works. We work closely with the Environment Agency and other partners to minimise the environmental impact of these incidents, on the rare occasion that they occur.

In the 2014 calendar year, we recorded a total of just below 49 sewerage related pollution incidents (measured per 10,000km of sewer length) – which is in better than the industry average. The majority of these incidents were classified by the Environment Agency as minor (category 3) incidents.

Serious sewerage pollution incidents


In the 2014 calendar year, there were 0.5 sewerage related pollution incidents (measured per 10,000km of sewer length) considered to pose a serious environmental risk, according to the Environment Agency’s classification scheme. This represents a performance which is better than the industry average.

Discharge permit compliance


Our sewage treatment works must meet strict Environment Agency discharge permit conditions which govern the treatment and disposal of wastewater. In 2014, over 98% of our works met these standards which although being slightly lower than the EA target for a green status, is better than the industry average and means we have performed better than our target for the last seven consecutive years.

Sludge disposal


Sludge is a by-product of the wastewater treatment process. We produce around 200,000 tonnes of sludge per year, some of which is recycled as fertiliser for agricultural land. This use is subject to a variety of controls, in order to prevent environmental pollution and safeguard human and animal health.

In 2014/15, 100% of our sludge disposal met regulatory requirements, achieving a green status for the measure.

Financial indicators

Post tax return on capital


Our operating profit, less tax, as a return on regulatory capital value, was in line with the post tax return assumed in price limits for the 2010 – 15 period of 4.9%.

Credit rating


We target an A3 credit rating from Moody’s rating agency, as we consider that this best mirrors regulatory assumptions. This credit rating target has been in place since 2007 and we continue to be rated A3 with a stable outlook. In line with the Ofwat reporting guidance, our KPI measure shows the lower rating issued by Standard and Poor’s rating agency of BBB+. The split ratings reflect a difference in methodology employed by the credit ratings agencies, particularly in respect of infrastructure renewals accounting.



Our net debt, as a percentage of total regulatory capital value, was 63.4% on 31 March 2015. This compares to 61.4% on 31 March 2014. Gearing has been calculated using a United Utilities Water (UUW) net debt number including derivatives.

Interest cover


The interest cover ratio for 2014/15 is 2.4. This represents the number of times our profits, before interest and tax, cover interest due on all our borrowing.