Plugging the 3,170 million litre leak

Ahead of industry league tables on leakage released later this month Utility Week examines the scale of the problem, how Thames got a handle on the issue to exceed its target after missing three in a row, and the promising technologies that are making finding and fixing leaks more effective.

Leakage rates peaked in 1994-95 when 5,112 million litres (Ml) were being lost each day. Last year 3,170 Ml were lost every day, a vast improvement on 25 years ago but clearly the task ahead in considerable.

Ofwat threw down the gauntlet with PR19 and set a 16 per cent target to cut leakage across the country by 2025 with each company having individual outcome delivery incentives (ODIs) to meet during AMP7.

Thames Water was set a stretching 20 per cent goal after missing three of its targets in AMP6. After 10 years of meeting its goals the company fell behind and was subject to an Ofwat investigation in 2017 that shone a light on the mismanagement between Thames and its contractor teams.

Serving a quarter of the population, Thames has its own specific challenges including the sheer volume of people living in the capital and infrastructure that dates to Victorian times. As well as that, significant amounts of the 32,000 km of aging pipes are laid in London clay, which is sensitive to both cold and warm weather, causing them to contract and expand. This leads to bursts and leaks that are tricky to access under the streets of the capital.

The scale of the problem

As legitimate as these difficulties are, critics also pointed to a series of management decisions which exacerbated the problems.

During AMP6 Thames worked with an alliance of contractors, which it did not hold to performance targets but instead relied on financial incentives to drive performance. From the offset targets were missed.

Ofwat’s 2017 investigation found relationship problems between the company and its contractors. A source close to the company told Utility Week: “One thing Thames learnt from the leakage was they did not have enough oversight or control as well as poor management over the companies working with them. These were not always acting in the company’s or customer’s best interests.”

The report noted a feeling among the alliance that the penalty for missing targets was relatively small compared with the cost of fixing leaks.

Ofwat criticised Thames’ board for not taking a more proactive approach to its leakage reduction performance and responding more quickly when contractors were materially failing targets.

A management overhaul followed, and the company made major efforts to get to the root of the problems and ramped up its efforts to find and fix leaks. This included a move away from the contractor alliance model to bring more activities back in-house.

Back on track

Now the company is spending £1 million every day on leakage and in its end of year results it boasted the industry’s biggest reduction in leakage this century, fixing an average of 200 leaks each day.

Thames claimed its leakage performance was the best “for more than 30 years” as it had saved 95Ml/ day more than the previous year exceeding its target by 11Ml/day.

Interim executive chairman, Ian Marchant, who has been instrumental in the company’s turnaround, said after three years there was no denying it would be incredibly challenging to get leakage back on track. “However, our increased focus and productivity, coupled with the dedication and sheer determination of our people and the contractors supporting us, meant we were able to go beyond our 2019/20 target of 606 Ml/d. As we move through the new regulatory period, we’re committed to keeping up the positive momentum and maintaining this improving trend.”

AMP7 strategy

As well as a fresh approach the company also has an arsenal of detection techniques and data-driven tools to stay on top of the leaks including rolling out smart meters across its region over the coming five years.

The company will continue to work with partners and suppliers to meet its 20.4 per cent reduction target by 2025, which is above the sector average in acknowledgement of previous failings.

It has increased the number of leak detection technicians it employs and introduced a programme of field audits to validate their work. The teams use data to judge where leaks are occurring and can tell repair teams where to dig. Teams are getting to grips with the environmental causes of leaks by examining soil conditions and what effect it has on pipes and assets. As well these studies, Thames has been developing digital detection tools to speed up finding faults within specific areas of the network.

Pinpointing where leaks are, using data analytics, is part of the strategy to tackle leakage reduction and will mean teams can use the right intervention at the right time to fix problems as they arise.

Steve Spencer, operations director at Thames, said data from the 450,000 smart meters that feed back 10 million reading a day helped the company meet its targets. He said: “Working with our customers, the data has given us a much greater understanding of what’s happening underground and saved millions of litres of water every day. The backlog of repairs to water pipes is down to its lowest level in a decade.”

To further its progress the company introduced a data-driven performance management tool that it said could deliver a 12 per cent efficiency improvement to ongoing leakage repairs. It involves closer communication between supervisors and scheduling teams as well as standardisation of processes with a dashboard of performance information.

Brave new AMP

The start of AMP7 has seen a flurry of announcements around technologies and partnerships aimed at tacking leakage including SES Water extending its work with Vodafone to utilise Internet of Things technology with its acoustic loggers, sensors and smart meters. These connect to Vodafone’s narrowband radio waves to improve the quality and details of coverage in built up areas.

Portsmouth has reached its lowest ever level in the past year with a 19 per cent reduction thanks to acoustic loggers. This year the company is investing in pressure monitors, which are more effective than loggers on plastic piping.

During lockdown South West Water’s leakage teams made significant progress – both in rural parts where distancing was easier, and industrial areas which ordinarily would have been too loud to detect irregularities in the pipes.

Network director Mark Hillson said the challenges of AMP7 required a new approach, which for South West meant a complete overhaul of leakage.

It has moved away from measuring against static targets to include transitional rate of leakage, and to understand customer-side leakage better – which was around 25 per cent.

“The sector knows it’s an industry-wide challenge and we all need to come together to understand best practice from across the industry to achieve the targets. The challenge is bringing it all together and trying to make sure we are all moving at the same speed.”

Developments in artificial intelligence and machine learning mean some repeatable, manual tasks to monitor pipes and assets can be done by machines analysing data and sound files instead of humans.

As more work than ever is done by all companies to find and repair leaks it stands to reason that the “easy wins” will have been located and repaired so attention now is on smaller leaks that can go undetected for many years. Finding these early could prevent more destructive bursts from happening in the future.

Using sensors that pick up on irregularities in the pipes allows technicians to pinpoint where water is being lost in a pipe and allow repairs to be made early.

AI makes use of algorithms to distinguish the different sounds within pipes and identify which of those would be a sign of a leak.

Elsewhere, Affinity is rolling out the use of step testing to find leaks in its network. The method, which is not widely used, relies on well-mapped underground assets – something Affinity is confident of because it has a substantial collection of asset maps. Parts of the network are segmented and stretches of pipe can be isolated from the network to spot pressure fluctuations or leaks with minimal disruption to service.

Yorkshire has also committed to invest in its smart network, with £50 million earmarked for leakage reduction. This includes a project, which is nearing completion, to deploy 4,000 monitors into a smart water network pilot.

Working with BT among other partners Yorkshire has created an Internet of Things network that the company said will, if successful, “revolutionise the way leaks and interruptions to supply are managed in the future”.

Smart water devices will monitor and analyse acoustics, flow, pressure changes and water quality. The network will integrate data from these and existing sources and present it in a single visualisation platform which will include a digital twin of the water network. The platform will use AI to cluster data sets, and remove false positives, to accurately inform asset and operational decision making.

South East Water has also trialled a smart water network across north Kent with Vodafone technology. The trial provided insight into how clusters of irregularities in pipework could be better interpreted to find problems as well as identifying where water is being lost on the customer side far quicker.

The innovation displayed in the initial quarter of this AMP shows the appetite for hitting the ODIs, while the industry’s pledge to triple the rate of leakage reduction by 2030 is a bold statement of intent that could catapult the sector towards a brighter future in which there is no reason to criticise or question asset management. The collaboration encouraged by Ofwat through the innovation competition underlines that leakage and the reputational repercussions of not improving are a key challenge for the whole sector to overcome.