As storm events grow more severe, so does the risk of inflow and infiltration – highlighting the need for smarter, more resilient sewer system management.
Climate change is intensifying the water cycle, driving more extreme weather events across Australia. As a result, the risk of inflow and infiltration in sewer systems increases, placing greater pressure on downstream network assets and raising the likelihood of disastrous spills.
The issue is amplified in areas where traditional gravity fed systems are deemed cost prohibitive and alternative systems like low pressure sewer systems are used, such as in areas of hilly and rocky terrains or where old and complex septic tanks need to be replaced.
Many of the brilliant minds at South East Water and its commercial arm, Iota, have first-hand experience with these challenges, and saw that the water industry had a need for a solution that could manage difficult terrains and that didn’t just monitor, control and optimise an individual sewer system – but managed the overall network too. Enter OneBox.
Ticking all the boxes
South East Water originally developed OneBox – a low pressure sewer system – to monitor its wastewater assets and identify issues without the need for customer intervention. However, the technology quickly evolved into a smart system that could digitally manage an entire low pressure sewer network in near real-time.
To tackle challenges like inflow, infiltration, spills and network overloading, sewer asset owners needed a solution that could help them take a proactive approach. To do this, it was identified that OneBox needed to combine clear network visualisation with real-time data and control functionality to turn an essentially dark system into a smart one.
OneBox was put to the real test when South East Water, supported by Iota, began a project to replace around 16,500 septic systems with a low-pressure sewer system controlled by OneBox.
Implementing the devices on such a large scale meant that Iota had the perfect platform to continuously enhance and refine OneBox by incorporating operator feedback throughout the project.
Fighting spills, OneBox at a time
OneBox allows operators to remotely monitor their sewer system in near real-time through a user-friendly portal.
Operators can turn pumps on and off via the portal; they have clear visibility of the entire network including tank levels, pump operation, power usage and alarm status; and can run diagnostic reports to identify potential issues.
But what makes this technology so clever is the way it leverages data to pre-empt issues before they become serious problems and removes the need for the customer to report an issue.
OneBox tracks the number of times the pump is discharged throughout the day and notes how this typically fluctuates on weekends or public holidays.
It then pulls rainfall data from the Bureau of Meteorology and overlays this with the pump data to create a complete profile of how the sewer discharge system should work, regardless of weather. This means that a pump operating outside that profile, particularly during a rainfall event, is an indication that there is infiltration in the system.
When this happens, operators can use the OneBox portal to see which tanks are affected, if the pump is running and whether the water level is dropping.
The portal also uses historical operating data to assess surrounding pumps and tanks to see if the issue is isolated to just one tank outlet or if it is a potential network blockage.
This helps crews to pinpoint the severity of the issue and make an informed decision about whether it can be addressed remotely – thereby avoiding unnecessary site visits.
Today, OneBox is being used in sewer networks both across Australia and overseas – and each case provides Iota with an opportunity to collaborate directly with users to further mature the product and develop new features to meet specific customer needs.
In Altogether Group’s case, a low pressure sewer system was chosen to help minimise stormwater infiltration into its network at the Gables new development area in Western Sydney.
By identifying and eliminating infiltration, Altogether Group can meet the community’s needs with a much smaller treatment plant. However, while pressure sewer systems are resistant to infiltration in the network itself, the on-lot pipe connections and plumbing are still vulnerable, particularly in areas like Gables where there is a high groundwater level.
Because these low-pressure systems rely on pumps and other mechanical components, they also require a lot more work to maintain. Although pumps in these systems are typically fitted with sensors, unlike OneBox they often only monitor wastewater levels and trigger a simple alarm when they detect an issue, which the operator must then go out and respond to.
These basic alarms don’t provide crews with any visibility or control of the network, meaning they could potentially be making unnecessary trips or in some cases they might even be alerted too late.
Boosting community resilience
Altogether Group is a multi-utility service provider that delivers sustainable water, power and data services to more than 500 communities in both greenfield and brownfield environments.
Altogether Group Executive General Manager – Water, Doug Fagerstrom, explained that the company works together with developers and communities to deliver reliable, localised essential services.
“We help those communities become more resilient and self-sufficient by integrating local resources,” he said.
“For example, at Gables in Box Hill, we have a recycled water plant within the community. So, when the wastewater comes to our plant, we treat it and send it back out [to the community] as recycled water, which can be used for things like irrigation and car washing.
“This reduces drinking water consumption, cuts down [the need] to pump large volumes of water across Sydney for treatment, and allows [the water] to be used locally.”
Mr Fagerstrom said that this recycled water plant is supplied by a pressure sewer network, but the original system didn’t offer much in the way of visibility of the network.
“Initially we had a standard pump controller and pump system. There’s a small tank in everybody’s front yard, and inside that tank is a small pump that pressurises the sewage and pushes it to our treatment plant,” he said.
“The system we had was analogue. It had a red light [that would come on] if there was a problem and the customer then had to call us if [they saw] that red light on the box.
“That worked fine, except we didn’t have good visibility of the kind of problems that we were having, or what was happening during a rainstorm.”
These tanks are the most susceptible part of the network to inflow and infiltration, and with Gables also navigating a seasonal high-water table and a recent increase of significant wet weather events, Altogether Group knew it needed to take a proactive approach.
After investigating its options, Altogether Group decided that OneBox, and especially its web portal, was just the solution the team needed. Iota then collaborated with the company to understand its specific needs and, where necessary, tailor the product to its specific requirements.
“OneBox, with its data connectivity and web portal, now allows us to monitor the individual status of each customer that’s connected,” Mr Fagerstrom said.
“[Because] we have real-time, alarming and monitoring, we’re able to go out and perform some type of maintenance before the customer was even aware there’s an issue. [Whereas] the old system was very dependent on the customer to take action.”
When an alarm is activated in the OneBox portal, Mr Fagerstrom explained that the first thing operators do is check the level of the tank to determine how urgently they need to respond.
“If the tank has pumped itself down already and there was a failure during that process, then we’ve got a bit of time because it takes a day or two to fill up a tank from a house, depending on the number of occupants in the house,” he said.
“We also have the trend data from the customer, so we can go back and see how many times the pumps operated in the last few days to help us estimate when we need to have that situation resolved. It also helps us identify when customers might have a leak they’re not aware of that’s draining into the sewer.
“For instance, during the construction of one customer’s property, the builder cracked one of the sewer lines by driving over it with some equipment.
“We noticed an unusually high amount of flow coming from that property, so we went out and we inspected our equipment to make sure it was okay. Then we got a plumber out to camera the sewer lines and they found a cracked pipe. The customer was able to then go back to the to the builder and get them to fix it under the defect liability period.”
Proactive monitoring and control
To meet Altogether Group’s needs, Iota incorporated custom reports into the portal that are sent out every day. These reports provided more granular hourly pump runtime data on wet weather days and highlighted pumps that ran more than a certain number of times per day.
This information enables operators to more effectively diagnose issues and differentiate between inflow of stormwater from illegal connections and infiltration caused by water table ingress.
Mr Fagerstrom explained that OneBox also allows operators to monitor and adjust flows based on network capacity.
“We can use the tanks as temporary storage during rain events to manage inflows into the treatment plant,” he said.
By holding flows in tanks reaching capacity while pumping from others nearing capacity, Altogether Group can help downstream assets manage increased loads. And in limiting the number of pumps operating concurrently, the company can carefully manage and smooth flow to the treatment plant – reducing the risk of it being overloaded and overflowing.
“By maximising the system to store sewage so [it doesn’t overload] our plants, we can minimise our footprint within the community,” Mr Fagerstrom said.
For Altogether Group, the benefits of OneBox are multilayered. Not only does it empower the team to keep spills at bay and help safeguard the company’s assets from damage, but it also allows the company to provide the best possible service to its customers.
OneBox transforms low pressure sewer systems into intelligent, responsive networks that deliver efficiency, reduce costs and help protect the environment. With its combined control functionality and portal visibility OneBox currently provides a smart solution that no other low pressure sewer system can offer.
For more information, visit iotaservices.com.au
