New kinds of data, new types of modelling
Water asset owners are exploring new ways to capture data and analyse the findings to take early intervention if required.
Using sensors and analytic services on some large water pumping assets, UK data acquisition company 8power recently completed a remote condition monitoring trial with Anglian Water.
The water utility that covers one of the driest areas of the UK is investing heavily in innovation in a bid to build resilience to drought.
Its latest move is to deploy a cloud-based sensor system that monitors asset health. The system monitors energy usage and parameters such as changes in vibration, temperature, and humidity and flags events or changing patterns which enables a more proactive maintenance approach.
In a second phase, the scheme will be rolled out to multiple Anglian Water sites which will be monitored with the latest generation of 8power's self-powered remote sensors.
Claimed benefits include helping Anglian Water better understand asset operation and prioritise the most critical network assets, thus reducing downtime and repair costs.
As Rich Fielding, Anglian Water’s hydraulic operations engineer, noted in a statement: “We see an opportunity to improve efficiency and the service we provide to our customers by shifting to condition-based maintenance regimes.”
Data from space
Today, the growing importance of remote data acquisition and analysis is transforming the water industry.
For example, earlier this year Detection Services working with the Oxford, UK-based geospatial analysis company Rezatec secured a contract to monitor any potential structural and environmental changes at Hunter Water’s Grahamstown Dam.
Located near Newcastle in Australia, Grahamstown Dam is Hunter’s largest drinking water storage facility, holding up to 182,000 million litres of water. It provides around half of the drinking water used by Hunter Water.
The remote asset monitoring programme offers a highly targeted approach to identify hotspots of terrain movement, soil saturations, vegetation growth, moisture levels and structural movement.
As Camilla Braithwaite, Product Manager at Rezatec, tells Aquatech Online: "For dams, the primary analysis that we use is on ground motion, and we use synthetic aperture radar."
Rezatec uses both commercial and open-source satellite data.
"Since about 2016 the capabilities have massively improved with the launch of the Sentinel 1 pair of satellites that have much better resolution," says Braithwaite, adding: "They have to revisit cycles from around 6 – 12 days and radar can still capture data when it is cloudy or at night."
Not only is this a high-frequency assessment, but the data can also be interrogated so that it is possible to identify anomalous ground motion of just a couple of millimetres.
"When considering a dam, you might get a surveyor visiting once or twice a year who can measure accurately, but on the whole, more typical monthly visits are more likely to be someone looking for large cracks,” she adds.
"We are measuring movement to the millimetre a couple of times a month, and from that, you can see trend patterns emerge."
“We are measuring movement to a couple of millimetres a couple of times a month, and from that, you can see trend patterns emerge. Because the data is captured remotely and frequently, it reduces the requirement for ground-based efforts, thereby enabling more efficient use of resources as well as decreasing risk and cost of failure by spotting it early."
An initial survey of a minimum of three years of historical data allows Rezatec to establish a baseline of movements within the structure which occur as the reservoir level rises and falls, for example.
Subsequently, Rezatec looks at the data to establish where anomalies fall outside that pattern, and the data flags up potential issues.
Any anomalous readings are indicated graphically to allow engineers to examine the data and if required, send engineers to a specific location on site for a physical examination and investigation.
The threshold for action will depend on a range of conditions, including the likelihood of failure as well as the consequences of any such event.
Growing risks need better solutions
The need for more sophisticated monitoring and analysis is growing as a result of emerging challenges for water asset owners.
“The potential risks for asset owners are increasing,” says the product manager. "Not only were a lot of these structures built many years ago, everyone now has an increasing consequence of failure due to increasing population density, for example.
“Every dam owner has a duty of care, and many dams are getting quite aged and need monitoring more frequently than dam owners can achieve."
"Every dam owner has a duty of care, and many dams are getting quite aged and need monitoring more frequently."
Although not every failure mode can be identified through satellite observation, by monitoring such structures to the millimetre, early intervention and action can be taken before catastrophic failures occur.
As Braithwaite says: "You can take action before the disaster happens because you can see the smallest abnormal movement. Gathering data every month means you are on top of the issue.”
Novel monitoring modes can also identify problems that may not be obvious during a typical visual inspection.
For instance, satellite data can also reveal other indications of potential failures that are not related to the movement of the structure. Seepage can be identified through the growth of plants in an otherwise arid environment, for example, and such plant growth can be seen with satellite observations. Infrared rather than radar can be used to pick up the vegetation.
“Vegetation growth can act as a proxy for seepage, and we have done that for Hunter Water in Australia. We picked up a couple of anomalies which turned out to be newly sown grass, but it was great to be able to pick up that level of detail,” she says.
Radio and infrared interrogation of ground movement and vegetation can also be used to monitor other water assets, such as buried pipelines, to identify leakage.
Assessing the costs of failure
With climate change, an ageing asset base, increasing consequences of failure and steadily more stringent regulatory requirements, water system asset owners have to be a lot more proactive in identifying and preventing leakage and potential failures.
Indeed, the potential consequences of the failure and the value at risk are often factored into any comprehensive data analysis. This can include factors such as the cost of road closures, third party liabilities, and all other potential costs to not just supply a risk of failure but also enable data-led decision making by identifying the highest risks too.
As Braithwaite says: "Being able to have that entire risk picture with both the consequences and the likelihood helps asset owners prioritise their budget allocation for repairs and replacement of their network."
"Being able to have that entire risk picture helps asset owners prioritise their budget allocation for repairs and replacement of their network."
The shift towards better methods of data acquisition and more sophisticated analysis is building to include new types of data.
"We incorporate that with our satellite data and create a likelihood of failure model which establishes across the whole of the network which sections are more likely to fail than others based on the historical data and the various attributes and the environment that we have collected,” says Braithwaite.
She adds: "That likelihood of failure for a specific section or a district metred area is significant when you are sending a crew out to dig up a pipeline."
Indeed, helping smarter operations by incorporating new layers of data to feed into the model and give intelligent information to clients is an essential part of this trend.
