Innovative drone tech helps nip toxic weeds in the bud

As the Hawkesbury River region in NSW continues to contend with devastating natural disasters, one local Council has revealed a lesser-known side-effect of the area’s heavy flooding and is combatting it with innovative drone technology for the first time ever in the region.

According to the NSW Reconstruction Authority’s 2024 Hawkesbury-Nepean River Flood Study, the region has one of the highest flood risks in Australia. Its 2022 flood event was the worst of its kind in almost 50 years, and floods have occurred as recently as June 7 this year, when over 160 millimetres of rain was dumped across the region in just 24 hours.

Hawkesbury River County Council (HRCC) represents four key local Councils in Western Sydney and is responsible for weed management within the Hawkesbury-Nepean region, covering a vast 3,800 kilometres of land. According to HRCC, floods are providing fertile ground for invasive weeds to flourish, threatening the region’s biosecurity and primary industries.

“Weeds pose a significant risk to the Hawkesbury’s farmers, landholders and community. They have the power to reduce crop yield, clog waterways, outcompete native plants and even poison livestock,” said HRCC’s General Manager, Chris Dewhurst.

“Floods are a significant contributor to the spread of weeds, distributing plant matter over large distances. Containing them is a constant challenge, and we are always looking to new innovations to give us the upper hand,” he added.

HRCC’s Biosecurity Team Leader, Toby Walker, is now combining his background in computers and passion for gaming to tackle the spread of noxious plants using a specialised drone to map weeds. It represents the first time that a drone has been used for weed mapping in the region, bringing HRCC a step closer to eradicating and containing numerous invasive weed species.

Armed with a brand-new DJI Mavic 3 Multispectral drone, Toby surveys large areas for certain weeds before helping the team form their plan of attack.

The Mavic 3 drone was purchased with funding from the Early Needs Weed Recovery Grant, a grant delivered by Greater Sydney Local Land Services aimed at helping primary producers overcome the damage caused by major floods. Typically used for agriculture, the drone is fitted with five high-tech cameras, allowing Toby to spot new weed growth and analyse plant health within a given survey area.

Toby credits his tertiary qualifications and his hobbies for giving him an unconventional leg-up in his role.

“I have a real interest in computers and video gaming. When I left school, I studied Computer Assembly and Repair before finding my current role, which is very different! I quickly discovered that I had a real knack for weed management and genuinely enjoy it,” said Toby.

“When we started taking the Mavic 3 out for test drives, I realised just how similar the controls and software are to that of a video game, they require a great deal of hand-eye coordination. Operating the drone turned out to be very intuitive for me.”

The drone can cover up to 200ha in a single flight, making it an indispensable tool for surveying large quantities of bushland. Interestingly, there are a lot of restrictions that Toby must consider when using drone technology.

“The drone can’t leave our line of sight during weed mapping, so I need to control it without looking at the remote. It helps to have some muscle memory, and gaming has definitely helped me in that sense,” he said.

“It’s great to be able to bring a unique skillset to the HRCC team, and while we’re still in the early stages of using the drone, it’s a really cool piece of technology that has been a lot of fun to operate.”

While his love for games has made Toby’s work more enjoyable, it doesn’t detract from the importance of his job. Because the Hawkesbury-Nepean Valley presents such a high flood risk, weed management organisations like HRCC must rapidly innovate to contain and eradicate weeds before they spread out of control.

“We cover a huge area of land as part of our work, and people often underestimate just how large it really is. Drones help us to respond rapidly when our member Councils or community need our help. They also help us to cover more ground and survey hard-to-reach areas, like gullies,” said Toby.

“When we talk about weeds, we have to consider their impact, which is often broader than what people expect. A weed isn’t just a plant – they can negatively affect our environment, community, and primary industries, so it’s important work that we’re doing,” said Toby.