A new underwater drone is helping Coliban Water to optimise its tank inspection process and improve the service it delivers to customers.
Coliban Water’s experts are now able to deploy a drone underwater to look more closely at a tank’s interior. Previously, internal inspections often meant a tank would have to be taken offline to allow for this work.
Coliban Water General Manager Asset Lifecycle, Marsha McMonigle, said modern technology was making it faster and safer to assess tanks and water storages, often with no interruption to customers.
“Our drinking water tanks are inspected annually and before this technology was available, our assessments were dependent on access requirements,” Ms McMonigle said.
“To clean the tanks, we often needed to use divers and take the tanks offline.”
Depending on the tank, using divers can potentially take a whole day and requires extra safety precautions – such as having safe access to the top of the tank, and preparing rescue plans – as well as other dive-specific considerations, like time the spent in the water and how deep the tank is.
“We have moved to newer technology, which has involved our team collaborating with Bass Strait Subsea. They are able to send a remote-operated drone down in the water to take good look inside the tank with a high-resolution camera,” Ms McMonigle said
“Using a drone minimises safety risks, improves our water quality information, means less disruption for customers and allows us to better plan our works.”
Cleaning works now entail teams using remote-operated vehicles – similar to pool cleaners – to pick up sediment that has naturally built up in tanks over time. Divers are sometimes still used to conduct physical inspections inside the tanks and complete more complex maintenance or repairs.
Sediment build-up in water storage tanks can happen over a number of years as minute particles and minerals in the water settle at the bottom of the tanks.
The Pyramid Hill tank was recently inspected using drone technology, which allowed divers from Aegir Divers to enter the tank and quickly and confidently remove debris and sediment.
“The reports provided from the drone give valuable feedback on the internal and external condition of our tanks,” Ms McMonigle said.
“We can see more things than we have previously, including how much sediment is in the tank and where it might be degrading. We want to pick those things up and proactively plan cleaning or rectification works. In most cases we can now get the tanks cleaned while they are online and with no interruption to customers.”
Featured image: The drone helps inspect one of the water tanks in Tooborac. Image: Bass Strait Subsea, courtesy of Coliban Water.