SES Water seeks out below-ground intelligence

Collaborative work to assess the condition of pipes in the Sutton and East Surrey region is set to give SES Water unrivalled intelligence about its below-ground assets

By James Brockett

SES Water is starting work on an ambitious project that will see it measure the health of its pipe network, identify the causes of leaks, and ensure that its mains renewal is targeted with maximum efficiency.

The water-only company is working with Echologics and Atkins to measure pipe thickness in 30 of its district metering areas (DMAs) using non-invasive acoustic technology. The data from this year-long exercise will provide a comprehensive picture of asset condition which will then be used to decide which mains are chosen for replacement. Furthermore, the data will be analysed alongside a host of other network information to reveal the causes of leaks and deterioration so that repairs, enhancements or operational changes such as pressure management can be used to extend asset life. This is the first phase of work in an approach that the company plans to eventually roll out to all DMAs in its supply area.

The impetus for the project has come from the need for SES Water to meet stretching targets in its 2020-25 business plan to reduce leaks and to minimise bursts and supply interruptions, explains Daniel Woodworth, network strategy manager at SES Water.

“We have comparatively low leakage compared to the rest of the industry – we are up there in the upper quartile. However, like all companies in the industry it’s been a bit stagnant of late, as we’ve been holding our leakage at what was popularly termed the economic level of leakage,” Woodworth says. “In this AMP, we’ve been reducing by a fairly modest 0.1MLD per year, which equates to a 2 per cent reduction overall. So what we and the whole industry are targeting now, a 15 per cent reduction in leakage, is a significant increase and very ambitious.”

Water companies typically have little real-world data about the condition of their water mains, and instead use probabilistic models to determine which might need replacing: if multiple failures have occurred in pipes of a particular age and type, then the company will prioritise those categories of pipes for replacement across the network. However, pipes can deteriorate in very different ways according to variables such as water pressure, the frequency of pressure transients, surrounding soil conditions, the layout of the network and local patterns of water usage. Real data provided through the project will allow for more targeted replacement where pipes are genuinely at the end of their life, while also providing insights about the network which might help asset life be extended.

SES Water first starting talking to suppliers about acoustic condition assessment around four years ago, and immediately saw the potential.

“We were looking for something that could validate our probabilistic models – everyone in the industry has always wanted that,” Woodworth says. “However, the technologies up until this point have been invasive, involving digging down and inserting something into your mains or cutting a section out. That leads to disruption for customers, there are water quality risks, and it’s expensive. So when we learned about this non-invasive method we were keen to give it a go.”

A proof-of-concept trial involving five DMAs showed that the solution was both usable and scalable, and also demonstrated how the data could be used to perform a ‘health check’ on the network. This has led directly to the current project, in which Echologics will carry out acoustic condition assessment using its ePulse technology and Atkins will perform analytical ‘health checks’ using all the data available for the same areas of the network.

“The condition assessment will tell us what state the pipes are in, but the health check is the why and how – why has it got to that point, and how might asset life be extended,” Woodworth says. “The project as a whole will marry those two things together on a DMA basis and will help us to make decisions about intervention based on the expected future life of the asset.”

It is the first time a solution like this has been used on this scale in the UK water industry. SES Water has 300 DMAs overall, and the 30 chosen for the project are those believed to be most in need of intervention, but it would be both feasible and valuable to condition assess the whole network over the course of several years, according to Woodworth. Economically, the project is expected to pay for itself because the evidence of the proof-of-concept trial suggests that it can make the investment in mains renewal significantly more effective.

“The work being done this year is going to directly inform our programmes of work for AMP7 onwards. It may even influence it quicker – if we find a big pressure transient that’s occurring and we can trace it back to a particular cause, if we can go and solve that cause and prevent it, then we will and that could be an immediate impact,” says Woodworth.

“The project is going to be a real collaboration in the way it’s going to be managed and run. We’re working in full partnership on this one – there will be dialogue between all three parties and a constant feedback of information. We won’t finish up with separate pieces of work, it will be one complete piece of work, a real collaboration.”

-This article appears in the June 2019 issue of WWT magazine.