Our performance 2011/12

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 2011/12 figures make encouraging reading. Performance is graded by 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 indepth information.

Customer experience

Customer satisfaction (SIM)


Customers enjoyed a more positive experience when dealing with United Utilities in 2011/12 – but there’s still room for improvement.

New, user-friendly services and a more proactive approach to answering queries helped to reduce overall complaints by 31%, cut serious complaints (those investigated by the Consumer Council for Water) by 92%, and boost our rating in customer surveys by 49%. The result was an overall industry score (known as Service Incentive Mechanism or SIM) of 67 points out of 100, compared to 40 out of 100 the previous year.

Sewer flooding incidents


Internal flooding at properties can occur when sewers become blocked, damaged or overwhelmed during heavy rainstorms. It’s a messy, unpleasant experience, which is why we’re pleased that property flooding incidents fell to 500, compared to 1,063 the previous year. Investing money to increase the capacity of the sewer network, fitting homes with flood protection, a rolling programme of sewer cleaning and providing timely advice to families via our What Not To Flush campaign helped to bring numbers down. Fewer heavy rain storms also helped to reduce incidents.

Despite this progress, we still have more to do to bring internal flooding incidents down, and we have an action plan in place to further improve our performance.

Water supply interruptions

25 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 25 minutes in 2011/12. Use of our Water on Wheels service during bursts, and carrying out ‘live’ repairs which don’t require mains to be shut off, contributed to this improved performance.

Water quality


We take pride in every drop of tap water we provide for our customers. In the 2011 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 water quality and composition here.

Reliability and availability

Looking after the region’s water pipes


We have over 42,000 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 2011/12, we achieved a ‘stable’ rating – which means that overall, we are meeting our performance targets.

Managing water treatment works and reservoirs


We have 94 water treatment works and 184 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 2011/12 - meeting our performance targets.

Looking after the sewer network


Our vast sewer network comprises more than 76,000 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 2011/12, our overall performance overall was rated as ‘marginal’. Unfortunately, we failed to get a green light because the number of properties affected by internal sewer flooding caused by a collapse, blockage or equipment failure was higher than our target. We are working hard to put things right. We have an action plan in place to get our performance back to where it should be and the number of incidents recorded fell for a second consecutive year.

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 2011/12, the management and maintenance of these sites showed general improvement and exceeded Ofwat targets for the fourth consecutive year.

Tackling leakage

453 Ml/day

We’re working hard to control leakage on our network. Measures such as 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 2011/12. This is the sixth 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 453 megalitres of water per day, compared to the 2011/12 target of 464 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 scored a green light for security of supply in 2011/12.

Reservoir levels


Total storage in our reservoirs at the end of the 2011/12 financial year was slightly below average, at 92%, largely due to a very dry March. Our latest reservoir level figures can be found here.

Environmental impact

Greenhouse gas emissions

522 ktCO2e

An efficient water and wastewater service needn’t cost the earth. We’re on track to achieve a reduction in our carbon emissions of 21% by 2015, through sustainable procurement, designing out waste and generating renewable energy at our treatment works.

Emissions in 2011/12 totalled 522,000 tonnes of carbon dioxide equivalent, a reduction of 9% on the previous year. We are now 13% towards achieving our 2015 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 2011 calendar year, we recorded a total of seven three sewerage related pollution incidents (measured per 10,000km of sewer length) – which is in line with the industry average. The majority of these incidents were classified by the EA as minor (category 3) incidents.

Serious sewerage pollution incidents


In the 2011 calendar year, there were 0.7 sewerage related pollution incidents (measured per 10,000km of sewer length) considered to pose a serious environmental risk, according to the EA’s classification scheme. This represents a performance which is above the industry average.

Pollution from water assets


Environmental pollution can stem from our clean water network or treatment processes. 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 2011 calendar year, there were 1.9 such pollution incidents (per 10,000km of water main length) - resulting in an amber or average rating.

Discharge permit compliance


Our sewage treatment works must meet strict Environment Agency discharge permit conditions which govern the treatment and disposal of wastewater. In 2011, 99% of our works met these standards – our best performance to date.

Sludge disposal


Sludge is a by-product of the wastewater treatment process. We produce more than 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 2011/12, 99.1% of our sludge disposal met regulatory requirements – just short of the 100% required to achieve green status. This shortfall was due to a small number of cases where sludge was applied to certain agricultural soil types, leading to an excess of nitrogen in the soil. We have an ongoing programme to improve our performance in this area.

Financial indicators

Post tax return on capital


Our operating profit, less tax, as a return on regulatory capital value, was higher than the post tax return assumed in price limits of 4.6%.

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 64.5% on March 31, 2012. This compares to 63.2% on March 31 2011. Gearing has been calculated using a United Utilities Water (UUW) net debt number including derivatives. United Utilities Group gearing was 59%.

Interest cover


The interest cover ratio for 2011/12 is 2.0. This represents the number of times our profits, before interest and tax, cover interest due on all our borrowing.