Using digital simulation to inform sustainable growth

Shaun Nesbitt, Chief Digital and Information Officer, Urban

Shaun Nesbitt, Chief Digital and Information Officer, Urban

When faced with a big decision for your business, how often have you thought, ‘if only I had a crystal ball’? Well, let’s discuss what could be the next best thing – a digital twin.

A digital twin is an online model of a real-world asset or system, which can be used to simulate scenarios and predict how assets may respond.

While they’re not new, digital twins are becoming more sophisticated, which means they can better support planning and operational decisions that stack up against environmental, social, and corporate governance objectives.

So, what’s changed? Two things: we have access to more data and lots of it, and we have the computer power to, in real-time, adjust the parameters of a digital twin to simulate far more complex scenarios.

Like many cities around the world, our population is growing in South East Queensland (SEQ). That’s one of the big reasons essential service providers like Urban Utilities can benefit from using digital twins – to support sustainable growth, help us respond to natural disasters, and help make better planning decisions to lower the cost of managing our assets.

We deliver water and wastewater services to around 1.6 million people at Urban Utilities. The work we do plays an essential role in supporting liveability in our communities and protecting much-loved natural assets, including the beautiful Moreton Bay.

As our region grows, so does the demand for our essential services. ServiceService providers like us must sustainably keep up with demand to support liveable communities to support liveable communities.

Real world application – why is a digital twin useful at all?

It sounds like a strange question, but in reality, most digital twins that are in use have very few parameters and, in isolation, only provide a minor uplift across the broader ecosystem they operate in. But hope is not lost!

To understand and realise the value of the digital twin, I believe the conversation needs to be lifted above the individual model to the broader system.

In the context of our operations, further benefits will be realised if we can start joining digital twins that exist both across service providers in SEQ but also by sharing with our partners to enable decision-making at a regional scale better and tackle the shared goal of supporting sustainable population growth and keeping downward pressure on the cost to service our collective customers.

What are we doing at Urban Utilities?

At Urban Utilities, we’re developing an online receiving environment digital twin to enhance liveability outcomes in our service region. It’s expected to be completed in 2023, though we’re already using it to support our planning.

The digital twin shows our wastewater treatment infrastructure and the natural assets across our service region, including Moreton Bay, 100 kilometers of main rivers, and more than 40 urban creeks.

As part of our day-to-day operations, wastewater is treated to a high level, and the effluent is either returned to local waterways or supplied as recycled water for activities such as irrigation.

Local waterways are also the receiving environment for other inputs, such as stormwater run-off and sediment from stream bank erosion and development sites, which all influence catchment health.

Our digital twin models draw on data collected over the past 20 years and more than 100 input sources to allow whole-of-catchment waterway impact modeling, showing where and how sediment and nutrients mix and disperse in the receiving environment. The model uses hydrodynamic, and water quality data collected by our project partners and us and integrates data from external sources as required.

National Computational Infrastructure hosts the digital twin models in Canberra, and it takes around three weeks to run a full model simulation for eight input sources for a period of one year.

Through online access, users can enter catchment improvement or asset upgrade investment scenarios, run the model, and the system returns a report and simulation showing areas of potential environmental improvement. A more informed risk assessment and cost-benefit analysis can then be undertaken for chosen scenarios.

Why is this important?

The digital twin enables a data-driven, science-based, and collaborative approach to future planning.

By adjusting parameters, we can understand the extent to which the receiving environment responds spatially and temporally to a range of different inputs over selected timeframes.

This will be an important tool for activities including:

- Planning our future wastewater services;

- Understanding our environmental footprint;

- Catchment management;

- Stormwater planning;

- Wet weather scenario management; and

- Recreational water quality risk assessment and forecasting.

Through scenario planning, we can take a more holistic view and prioritise our investment in projects that maximise benefits for our communities, the local environment, and our operations.

This means exploring green infrastructure solutions instead of traditional grey infrastructure and grey-green hybrid solutions to support sustainable population growth in our service region.

Demonstrating the benefits of a proposed project using our digital twin also opens also opens the door to more opportunities to collaborate and partner with other organisations to meet our shared goals.

For example, in the past, we’ve partnered with the Port of Brisbane and Healthy Land and Water on a $2.4 million nature-based solution to reduce sediment and nutrients in Laidley Creek in the Lockyer Valley through streambank and riparian forest restoration. Fine sediments from these upper catchment streambanks impact the Brisbane River system and Moreton Bay during and after flood flows.

The project involved rehabilitating more than 3km of degraded banks along Laidley Creek by re-profiling streambanks, planting more than 20,000 native trees and grasses, and installing six in-stream structures to slow flows and stabilise the waterway. This prevents tonnes of sediment, nitrogen, and phosphorous from entering the waterways yearly.

By investing in green infrastructure, we avoided the need for a costly upgrade to our Laidley Wastewater Treatment Plant and are helping to protect valuable farming land from erosion while delivering a range of other environmental benefits.

We’ll be able to take these types of green infrastructure projects to a new level using our receiving environment digital twin and better understand the outcomes before we break ground.

This is just one example of how we can use our digital twin to support the delivery of our essential services to our growing region and achieve our purpose of enriching the quality of life.