Australian sewer innovation implemented in Ireland

Low-pressure sewer monitoring and control technology developed by Iota, South East Water's commercialisation arm, is being rolled out in Ireland's township of Gweedore following successful implementation in the PeninsulaEco (PenEco) project.

South East Water's PenEco project on Victoria’s Mornington Peninsula involves a smart hydraulic sewer network, which is monitored and controlled with OneBox – a device allowing for near-real time alerts within a pressure sewer system.

Irish Water has adopted a similar smart low-pressure sewer network in place of a traditional gravity sewer following a utility-to-utility conversation facilitated by Iota, between Irish Water and South East Water.

Sharing knowledge

Iota Technical Director Eamon Casey said the initial meeting between Iota and Irish Water instigated the idea of implementing the same pressure sewer system adopted by South East Water, as the Australian utility met similar topographical issues.

Irish Water faced the challenge of replacing dispersed septic wastewater treatment tanks in Gweedore, but due to topography, ground conditions and the nature of the development, a conventional gravity collection system was impractical from an economic and technical perspective.

The surface geology surrounding Gweedore, located in the County of Donegal, is dominated by blanket bog overlying shallow granite with protruding rock, making the installation and implementation of a gravity sewer network costly and difficult.

Furthermore, the County of Donegal was required to deliver a sewerage system in Gweedore under the Water Services Investment program.

“We have a culture within Iota – and more widely throughout our parent company, South East Water – to share learnings, insights and technology with our industry peers,” Casey said.

“Details of the PenEco pressure sewer system were highlighted and the alternative sewering method, along with the near real-time monitoring and control capabilities of OneBox posed a potential solution to many of the challenges being faced by Irish Water.”

Australian experience

The PenEco project on the Mornington Peninsula commenced in 2015, with the removal and replacement of around 16,500 septic systems between Rye and Portsea expected to take about 10 years.

Casey said the PenEco project is one of the largest pressure sewer installations in Australia and, when complete, will have in excess of 16,000 connections, all monitored and controlled remotely using OneBox.

“The OneBox controls peak flow on the network limiting the required infrastructure size and impact on downstream assets. The maintenance is reactive based on monitoring alarms reducing the spill risk and operational cost,” Casey said.

“Benefits of this approach include optimisation of infrastructure design and associated cost saving, reduced spill risk, improved customer outcome and associated operational cost savings.

“We have made several firmware and software updates over the course of the project in order to optimise the solution. A recent hardware redesign enabled enhancements in remote diagnostics and future-proofed device communications.”

Delivering innovation to Gweedore

Irish water Business Lead – Innovation, Standards and Technology Mark O’Callaghan said the option of a smart low-pressure sewer, similar to the PenEco installation, opened up an opportunity for Irish Water that hadn’t yet been investigated.

“We also saw the attractiveness of having a smart system that could be remotely controlled and managed,” he said.

Nicolas O’Dwyer (NOD) Consulting Engineers were engaged by Irish Water to manage the Gweedore project, with Iota delivering the detailed hydraulic design of the smart pressure sewer scheme, which consists of about 700 individual connections.

NOD Associated Director Nicholas O’Dwyer said Iota’s approach clearly enabled a more efficient and cost-effective solution to what are very difficult geological conditions for in-ground sewer systems.

“We saw the appeal of Iota’s smart pressure system, not only due to its simplicity and cost-effectiveness, but also because of cost estimates for a gravity sewer solution that proved uneconomic due to the difficult ground conditions,” he said.

The Gweedore system has been designed to manage flows and utilise individual units across the network as additional storage capacity in high-flow events, like post power outages or storm events, allowing for smaller diameter pipes throughout the system.

Environment One Corporation (E/One) was awarded a tender to install and connect the initial 700 grinder pump units in Gweedore, and Director of Engineering Derek Lachut said capital savings were achieved from reduced construction costs due to shallow trenches or trenchless installations and no requirement for major pump stations.

“Irish Water wanted to maximise the functionality of the system,” he said.

“E/One’s industry-leading reliability and ruggedness coupled with OneBox for command, control, and communication will drive extreme customer satisfaction and ensure success of the scheme.

“The E/One and Iota solution is set to deliver this.”

The Gweedore low-pressure sewer network project has now commenced, with the first cohort of properties in the rollout – 42 residential and two commercial – due to be completed in the coming months.