Townsville City Council
Queensland
Townsville City Council investigates water pressure complaints in the coastal suburb of Pallarenda using the Taggle Network.
As one of the early adopters of Taggle Systems innovative remote sensing technology, Townsville City Council (TCC) lead the way in collecting data from a wide variety of applications via Taggle’s Low Power Wide Area Network (LPWAN), to identify and solve problems.
One of these applications, is to remotely monitor water pressure to better understand pressure fluctuations, identify the cause of low-pressure complaints, quickly identify leaks and breaks in the network and to assess water pressure and flow rates to better inform infrastructure upgrade decisions.
Regular pressure complaints from the coastal suburb of Pallarenda kicked off the first project with an installation of three pressure sensors on residential connections at the meter.
Council already knew the suburb had the unfortunate circumstance of being fed by 2x 150mm reticulation mains that are supplied by a 450mm bulk main. The bulk main flow is influenced by a large butterfly valve which actuates when reservoir levels on Magnetic Island go below a set point. What TCC were unsure of though was how extreme the pressure drops were and if the watering window in the afternoon contributed to the problem as well.
The standard approach was to engage a consultant to provide a scoping study to upgrade the infrastructure by separating Pallarenda from the bulk main feeding Magnetic Island. This project was costed at approximately $4 Million. The team decided leveraging their existing IoT network to gather data to better understand of the problem might lead to a lower cost solution.
Until now, only short-term spot pressure checks had been completed, these mostly showed that the pressure was fine. Using just three remote pressure sensors on the Taggle network, sending data every 15 minutes painted a much clearer picture of what was happening.
TCC were able to detect and correlate sudden drops in pressure to SCADA data of the valve operations. What was very interesting was the pressure rises that seemed to correlate with the valve operation as well. Water hammer seemed to be a significant issue, with pressures exceeding the sensor detection limit of 10 bar (1000kPa). This was totally unexpected. The data also showed that the pressure drop during the watering times was not as pronounced as first expected.
With the new information and the ability to monitor the pressure in near-real time, TCC have shelved the new reticulation main project costed at $4 Million and instead have updated the telemetry on the valve itself to better manage the timings of the opening and closing on the valve remotely rather than manually, which will allow them to avoid watering and peak consumption windows. TCC are also looking at installing an actuator on the valve, allowing them to slow the opening and closing of the valve and even have partial opening to lessen the impact of water hammer and reduce pressure changes.
The data provided to inform these decisions came from just three low cost pressure sensors, attached to Taggle telemetry devices, sending readings via the Taggle LPWAN. Data is processed and delivered within Taggle’s Aqualus Vision software, making it a low cost, easy turnkey solution. The battery powered sensors will last for 4 years in the field without any human intervention, after which the batteries can be replaced for continued use.
TCC now have pressure sensors installed round its reticulation network and have solved many pressure challenges with the technology.
Summary
- TCC were able to correlate the sudden drops in pressure to the SCADA data of the valve operations – this validating our sensor readings.
- Pressure rises that seemed to correlate with the valve operation as well, water hammer seemed to be a significant issue, with pressures exceeding the sensor detection limit of 10 bar (1000kPa).
- Pressure drop during the watering times was not as pronounced as first expected, but still played a part.
- Data enabled us to shelve the new reticulation main project while we investigate options around better valve control and operation.
Solution
TCC are investigating a range of different valve operations:
- Slower opening
- Slower closing
- Opening to lesser extent for longer periods of time
Staff will monitor how this impacts the pumps on Magnetic Island, reservoir levels and triggers as well as large water users near the valve and reticulation offtakes (i.e. the large irrigated open spaces along the coastal fringe).
Most recently, work was completed upgrading the telemetry control of the valve and are now working towards installing a new actuator which will allow much more control over valve settings.