TUBES as a controlled test environment for low-threshold pilot projects

Deploying TUBES to address issues faced by drinking water companies

Drinking water companies desire a better understanding of the condition of their infrastructure, particularly the underground pipes that make up the mains network. A range of techniques are available for this purpose. One method for monitoring involves using optical fibres that are sensitive to disturbances such as strain, temperature and pressure changes.

In this project, the TUBES test environment will be used , a bespoke experimental facility at KWR Water Research Institute that simulates the Dutch drinking water distribution network as realistically as possible on a small scale. The facility includes pipes with a range of materials and diameters. The set-up also includes other typical components such as valves, connections, hydrants, pumps and facilities. There are even features for the simulation of leaking pipes and angular displacement. Most of the pipes are above ground and a small section of the network has been installed inside the building.

This labyrinth-like structure of the test environment can be used to address a range of issues faced by drinking water companies. The pilot studies in this project provide openings to identify the opportunities in this respect.

Three pilot projects in international alliance

The TUBES facility has been used to conduct a pilot study for Evides with Distributed Acoustic Sensing (DAS), taking into account installation, hygiene and leak detection capacity/reliability. The test facility is a welcome intermediate step in the direction of the ‘real world’ because a pilot project of this kind in a real pipeline can encounter hygiene concerns. The drinking water company was therefore aware of the possibility at KWR of using TUBES to obtain answers to practical questions.

At the same time, a technology supplier was looking for a suitable pilot project to test a new Distributed Temperature & Strain Sensing (DTSS) technology. From a research perspective, there was a wish to test whether strain sensors could provide added value in terms of detecting stresses caused by different factors.

All these elements resulted in an international alliance consisting of KWR, Evides and the technology companies Fluves NV, Vigotec NV and Aragón Photonics (Belgium and Spain). The experience gained will be extremely valuable for KWR in terms of learning about the potential of the TUBES facility as a research environment.

The following technologies play a key role in this joint monitoring campaign:

• DALI – A DAS technology offered by Fluves NV and Vigotec NV (Belgium). With this technology, an optical fibre is introduced into the mains through a valve/hydrant and guided through a route using a parachute. Different routes are being tried out to take full advantage of the “obstacle course”-like characteristics of the TUBES facility. Synthetic leaks and infiltration activities are simulated.
• BLAST – A DTSS technology from Aragon Photonics (Spain). This technology can be used to monitor temperature and strain along the fibre. To test this fibre, the load on the pipes and the angular displacement at connections are simulated.

Confluence of “market pull” and “technology push”

The monitoring campaign described here is the result of an international alliance between a research institute, a drinking water company and two technology suppliers. Our efforts show that a broad alliance of this kind pays off in several respects. Answers can be given to research questions. Low-risk trials can be conducted with technologies before they are deployed more widely. And the capabilities of these technologies can be tested before they are rolled out on a commercial scale.

Joint monitoring campaigns of this kind can provide a confluence of “market pull” (demand) and “technology push” (supply). The monitoring will take place in April 2023. The experience acquired will be shared with colleagues from other drinking water companies at a workshop that will include presentations by project participants and a demonstration of the technologies by the suppliers.