Dam monitoring with Rezatec13 October 2020
Philip Briscoe, Chief Operating Officer at Rezatec, shares details of the company’s dam monitoring solution, and explains how it can offer greater piece of mind for dam operators globally
Can you provide some background on the company?
Founded in 2012, in the UK, Rezatec has built a team of PhD data science and Earth observation experts and software engineers, that help business leaders to manage their ground-based assets and critical infrastructure remotely and at scale using our Geospatial AI products.
The AI models driving our products use satellite data because it is always ‘on’ and updated regularly and with many different providers, giving us an increasingly broad choice and plenty of data. Used together we can provide clients with detailed, highly accurate analytics across their entire asset base via a subscription-based delivery model. Rezatec serves four markets – energy, agriculture, forestry and water. We like trying to solve big problems for people that may not have fully realised the benefits of data-driven decision making.
Can you provide background details on your Dam Monitoring system?
Since 2015, Sentinel satellites have been able to provide 15 metre resolution data with a 6-12-day revisit cycle, pretty much anywhere in the world. That has been a real game changer. Since then we have developed a number of AI techniques that extract insight that can be used by dam owners and operators to see structural movement with millimetric accuracy and indications of seepage.
Dams are large, remote, geographically dispersed and getting harder to manage as they age and climate conditions become increasingly extreme. The impact or consequence of a dam failing can be catastrophic and with urbanisation, this consequence of failure is only going in one direction - up.
Our dam monitoring solution can be operated remotely, at scale and increase efficiency. It seems the perfect marriage.
What does the system offer to dam owners and operators? How does it work?
In a nutshell the system offers greater peace of mind.
Dam owners and operators receive notifications from our platform that indicate if the dam is moving in a way that is not normal and/or if there is potential seepage. We provide the data and analysis that shows if something is not behaving ‘normally’; every dam is different and our solution uses retrospective analysis to create a baseline for the data, or a basal rhythm. Dam owners and operators can then prioritise their skilled resources to the dams where our analysis indicates there may be a problem. It also directs the visiting engineer to the part of the dam that needs further inspection.
Our platform provides new data each month, which means it is easier to see the measurements in context, but also to carry out remedial work before something becomes a really big problem.
What kind of dam safety issues can, and have been, identified by the system?
Movement of the dam is a key indicator of a potential problem. Every dam moves as the water level changes, this is the basal rhythm and by analysing historical data we can use this to build up a picture of what is normal for that dam. Any anomalous movement can then indicate a potential safety issue but it is down to the experienced dam engineer to respond appropriately.
Seepage or leakage is another problem that can indicate a problem. We analyse the surrounding vegetation to see if the moisture and vigour of the vegetation is as expected. Again, we do this by analysing historical data to benchmark what is normal and what isn’t. For a client recently we identified an area of higher than normal vegetation vigour, and this turned out to be recently planted grass seed. The reservoir owner was quickly able to rule out any problem but it does show the delicacy of the solution and what it can identify.
Our solution is there to monitor the dam for the dam operator or owner. Monitoring frequency and to such a high level of accuracy means we can pick up problems when they are still small and potentially not visible to the human eye. The dam owner or operator can use these insights to prioritise surveys and inspections if required.
Rezatec’s Geospatial platform showing Rate of Ground Movement (mm’s per year)
Where has the system been used?
We have clients in the US, Canada, UK, Australia, and India. The retrospective analysis we do to create a picture of what is normal for that dam takes into account the local features of that dam so it can be used anywhere in the world.
Can you provide a brief case study of the system in use?
A client in Australia is using our Dam Monitoring product. Dan from Hunter Water previously needed to close a 4 lane 80km/hour highway to survey their Grahamstown dam, which they did once a year. Our solution is being used to change this to monthly remote monitoring. Our solution successfully correlated ground motion and vegetation anomalies with previous events and subsequent works.
In the future, anomalies that cannot be explained by local knowledge will prompt further inspection of the dam when needed.
Has the system evolved over the years? Are you looking to add any functions to the system?
We have established and tested this solution for ground movement and seepage across different types of dams; but there is still so much more we want to do. In conjunction with our customers and strategic partners, e.g. Black & Veatch, we are looking at developing the functionality so we can make it as easy as possible to review the data, communicate and update, and navigate to further information that is needed to triage an anomaly. We are also looking at how we can help dam owners predict problems with their dam to help them prevent problems in the future. Overtopping is one of the number one causes of dam failure, so we are looking at this as a key challenge we can help with.
Rezatec’s Geospatial platform showing Ground Motion Trends
How much does it cost?
This type of technology turns the business model on its head. Rather than one rather large fixed cost for surveying it, or for purchasing in-situ sensing technology that needs to be fitted and maintained for each dam, ours is a monitoring solution. This means you have access to the data and analysis on our platform whenever you need it and monthly updates that keep the information you need up-to-date. So, for a smaller monthly cost clients are getting greater peace of mind, and more informed decision-making so they can prioritise more expensive resources. Unlike surveys or sensors, solutions like ours can achieve economies of scale across multiple dams.
In our recent case study, Hunter Water, tried and tested other technology but were unable to find a comparable level of frequency and insight at such a competitive price.
What services do you offer to users of the system?
We offer ongoing remote monitoring of one or more dams, including:
- The retrospective analysis to give clients a better understanding of what the normal behaviour or basal rhythm of their dam looks like.
- An introduction and tour of the analysis and access provided. Training isn’t really required in depth as the platform is simple to use.
- Ongoing access to their dam data in an online platform visualised on a map and summarised in a dashboard.
- An indication of the location and degree of anomalies in both movement and possible seepage.
- Emails to notify the user when new data has been added and whether there are any anomalies to look into.