THE TERMS OF A NEGOTIATION.

There is a negotiation underway across the coastal canefields of Queensland that has been running, in various forms, for the better part of three decades. On one side: an agricultural industry that has shaped the identity, economy and physical landscape of the state’s wet tropics and central coast since the nineteenth century. On the other: a coral reef system of such ecological complexity and global significance that its condition is assessed, monitored and reported on by joint Australian and Queensland government programs, tracked region by region, catchment by catchment, year by year.

The question at the heart of this negotiation is not whether sugarcane farming has damaged Reef water quality. The science on that is settled. Sugarcane growing areas are the largest contributors of dissolved inorganic nitrogen, accounting for 78 per cent of the anthropogenic load flowing to the Reef. Nitrogen-based fertilisers are essential to sugarcane production, but when used inappropriately they run off into local waterways and out to the Great Barrier Reef. Catchment water quality monitoring and modelling estimates that approximately 55 kilotonnes per year of total nitrogen is delivered to the Reef, with approximately 12 kilotonnes per year of that being dissolved inorganic nitrogen — the form of nitrogen most easily absorbed by algae.

The real question — the one being negotiated on paddocks, at field days, inside regulatory offices and around boardroom tables — is whether the industry can change enough, and change quickly enough, to keep the Reef functional as a living ecosystem. Whether a commodity agriculture built on nitrogen-intensive monoculture can become, to use the term that has taken hold across government and industry, reef-compatible.

That phrase carries a great deal of weight. It does not mean ecologically neutral. It does not mean pristine. It means: operating within the bounds that science determines the Reef can absorb without losing its fundamental character. And it is against that threshold — difficult to measure, harder still to reach — that the industry’s better management practices are now being evaluated.

The civic and environmental record of this effort belongs to Queensland in the most concrete sense. sugar.queensland exists as the permanent onchain address for the Queensland sugarcane industry’s identity in the digital layer — a namespace that anchors, in lasting form, an industry whose relationship with this coastline is one of the defining questions of Queensland’s environmental future.

THE PROBLEM DEFINED: NITROGEN, SEDIMENT, PESTICIDE.

To understand what better management practices are trying to solve, it helps to understand the nature of what reaches the Reef when those practices are absent or insufficient. Three categories of pollutant dominate the scientific literature and the regulatory frameworks: nitrogen, sediment and pesticides.

Fertiliser containing nitrogen easily converts in soil and water to dissolved inorganic nitrogen, which plants and algae can absorb readily. This mobility means it can be lost quickly in run-off or drainage into waterways. Excess nutrients, particularly nitrogen, can upset the natural balance of Reef ecosystems. There is strong evidence that excess nutrients in the Great Barrier Reef contribute to increased outbreaks of coral-eating crown-of-thorns starfish. While most effects occur in the wet season because of greatly increased river discharge, some effects — such as crown-of-thorns starfish outbreaks — may continue for many years.

Pesticides present a different but related problem. Pesticides, including herbicides, insecticides and fungicides, are generally not found in the natural environment and can take months or even years to break down. They are carried in river run-off and have been detected in Great Barrier Reef ecosystems at concentrations high enough to affect organisms. The effects of ongoing low-level pesticide exposures in inshore environments are unknown but likely to impact coral fertility and reproduction.

Sediment compounds these harms by reducing light penetration and smothering corals and seagrass beds. Land-based runoff remains the most significant contributor to reduced water quality, resulting in the declining state of many inshore marine ecosystems. The main contemporary source of the primary pollutants — nutrients, sediments and pesticides, including herbicides, insecticides and fungicides — from the catchment is diffuse source pollution from agriculture.

This is not an abstract threat. The catchments that drain into the Reef inshore zone pass through some of the most intensively managed cane country in Australia — the Herbert, Haughton, Johnstone, Russell-Mulgrave, Tully, Plane and Murray catchments among them. The greatest coral reef and seagrass exposure to dissolved inorganic nitrogen is from these very catchments.

THE POLICY ARCHITECTURE: FROM VOLUNTARY TO MANDATORY.

The policy response to this challenge has evolved substantially over time, moving from voluntary best practice toward a binding regulatory framework. The transition was not smooth, nor was it uncontested.

For much of the 2000s and into the 2010s, the dominant approach was extension — public funding directed toward educating farmers, demonstrating alternative fertiliser management techniques and making the economic case for change. This produced genuine improvement in some regions, particularly where industry groups and regional NRM bodies built sustained relationships with growers. But the pace of adoption remained uneven, and the Reef’s water quality targets — set under successive federal-state agreements — were consistently being missed.

The Reef 2050 Water Quality Improvement Plan 2017–2022 was a joint commitment of the Australian and Queensland governments seeking to improve the quality of water flowing from Reef catchments. The plan identified how the water quality outcome under the broader Reef 2050 Long-Term Sustainability Plan would be delivered, with the long-term outcome described as: “Good water quality sustains the outstanding universal value of the Great Barrier Reef, builds resilience, improves ecosystem health and benefits communities.”

Underpinning this plan, and marking a significant shift in approach, was legislation. The Environmental Protection (Great Barrier Reef Protection Measures) and Other Legislation Amendment Act 2019 introduced restrictive regulation on industries, primarily agriculture, with the intention of reducing the amount of pollutants, nutrients and sediment entering the Great Barrier Reef lagoon. Cattle, cane, banana, crop and grain producers in Reef catchment areas were regulated, most for the first time.

The Reef protection regulations address land-based sources of water pollution flowing to the Great Barrier Reef, including agricultural and industrial sources of nutrient and sediment pollution from all six Reef regions: Cape York, Wet Tropics, Burdekin, Mackay Whitsunday, Fitzroy and Burnett Mary. The requirements for sugarcane focus specifically on retaining nitrogen, phosphorus and sediment on-farm to minimise run-off and improve water quality.

The regulations prescribe minimum practice agricultural standards that apply to sugarcane growers, beef cattle graziers and banana growers. These standards include commodity-specific practices to ensure that farmers can no longer use alternative high-risk farming practices likely to contribute excess nutrient and sediment run-off into the Great Barrier Reef catchment.

The agriculture sector’s response to this regulatory shift was divided. Industry bodies broadly accepted the principle of improvement while contesting some of the specific mechanisms. AgForce, the peak body for Queensland’s broadacre farming industries, opposed mandatory Reef regulations and instead sought to promote best practice and innovation through voluntary guidelines and an incentives scheme. The tension between voluntary adoption and enforceable standards has persisted as a structural feature of this policy space.

SMARTCANE BMP: THE INDUSTRY'S OWN FRAMEWORK.

Parallel to, and in many respects preceding, the shift toward mandatory regulation, the sugarcane industry developed its own accreditation architecture. The Smartcane Best Management Practice program — known universally within the industry as Smartcane BMP — became the central mechanism through which growers could demonstrate environmental stewardship and, critically, achieve recognised compliance with government requirements.

Since 2014, Queensland canegrowers led the development of Smartcane BMP to record and verify their practice improvements. The Smartcane BMP program is an industry-developed, robust and practical system focused on improving productivity, profitability and sustainability of farm enterprises. Through the program, growers self-assess their practices to determine if they are below, at, or above the industry standard. If their activities fall below the industry standard, the system shows what would be required to reach it.

The program focuses on three core modules through which growers can achieve accreditation and be independently recognised for their management of soil health and nutrients, irrigation and drainage, and weeds, pests and diseases. Becoming accredited in these modules remains the gold standard for Smartcane BMP.

The program’s growth has been substantial. Across Queensland, there are now a total of 801 enterprises farming 173,775 hectares accredited under Smartcane BMP, equating to approximately 45 per cent of the total cane area. Since commencement of Phase 4 in January 2023, an additional 152 enterprises farming 24,294 hectares have been accredited, with a further 258 enterprises successfully extending their accreditation for another five years, maintaining a 96 per cent re-accreditation rate.

The regulatory recognition of Smartcane BMP was critical to its uptake. Smartcane BMP accreditation is formally recognised under the current Reef regulations, providing accredited farming enterprises with an alternative pathway to compliance and ensuring they are not the focus of regulatory activities, including on-farm visits. These programs align to or achieve more than the minimum practice agricultural standards that apply for sugarcane growing, and program recognition enables the Queensland Government to acknowledge producers who are actively engaged in improving their practices.

The financial and market dimensions of the program have also grown. The sugar supply chain and the finance sector increasingly look to Smartcane BMP to assure them of growers’ sustainability performance, thereby helping these businesses meet the sustainability expectations of markets and investors. A major highlight for 2025 was finalisation of an understanding with the VIVE sustainable supply programme, which provides new opportunities for districts where mills seek accreditation to access a global sustainable sugar supply chain.

THE TOOLS OF PRACTICE CHANGE: FERTILISER, TECHNOLOGY, LANDSCAPE.

The substance of better management practices spans a range of interventions, some agronomic, some technological, some structural at the landscape scale. Understanding what they involve moves the conversation beyond the abstract and into the actual decisions made on individual farms.

At the core of nutrient management practice change is the principle of matching nitrogen application to crop need rather than applying precautionary excess. Improved management practices, such as applying the correct level of nitrogen for the crop’s needs at the optimum times for weather, are essential to maximise productivity and minimise the impact on the environment. This sounds straightforward, but the science of getting it right is complex. Nitrogen losses from intensive crop production into wet tropical catchments of north Queensland are a major threat to Reef health, yet owing to the lack of information on these losses and the extreme variability in climate and rainfall over very small distances, it has historically been difficult for growers to link nitrogen appearing in the environment to nitrogen management on their own farm.

Technology has moved to close that gap. CSIRO developed a suite of apps called 1622 to deliver information services to farmers addressing their concerns, making faster change in farm management practices possible, and helping growers reduce impacts on the Reef. The 1622 platform uses sensors, advanced data analytics and deep learning to help sugarcane farmers manage nitrogen fertiliser without affecting profits, with flow-on benefits for the health of the Great Barrier Reef. An independent evaluation found the 1622 apps could bring between $20.4 million and $62.9 million in economic benefits from 2021 to 2030, mainly in cost savings from reduced fertiliser use.

On-farm infrastructure also plays a role. Treatment wetlands, sediment basins, vegetated drains and bioreactors improve water quality on farms by slowing water flows, reducing the volume of water leaving the farm, and trapping and removing nutrients, sediments and pesticides from run-off or shallow groundwater.

Market-based mechanisms have complemented direct extension and regulation. An innovative pilot Reef Trust reverse tenders project used a market-based approach to reducing fertiliser applications on Burdekin sugarcane farms resulting in dramatically less excess nitrogen entering the Great Barrier Reef. Through these Reef Trust Reverse Tender projects, 111 sugarcane farmers in the Burdekin and Wet Tropics regions managing 27,854 hectares applied 643 tonnes less fertiliser nitrogen in 2017–2018 alone.

Addressing one of the persistent barriers to adoption — the risk that reducing fertiliser rates might reduce yields — the Great Barrier Reef Foundation developed an instrument directly tailored to this problem. A world-first insurance product, Nitrogen Risk Insurance, was developed to help farmers reducing their fertiliser use manage the risk of lower crop yields. This innovative approach was developed specifically for Queensland’s sugarcane farmers to overcome a significant barrier to adopting reduced nitrogen rates.

WHAT THE REPORT CARDS SHOW.

The annual and biennial Reef Water Quality Report Cards produced under the Reef 2050 framework provide the most direct measure of whether better management practices are translating into measurable improvement. The picture they present is one of real but insufficient progress.

Overall, there is continued progress, especially towards the particulate nutrient targets, with slower progress towards the dissolved inorganic nitrogen and sediment targets. There was very poor progress towards the dissolved inorganic nitrogen target — a 0.7 per cent reduction — and poor progress towards the sediment target — a 0.8 per cent reduction — across the Great Barrier Reef catchment in 2021 and 2022.

Within these aggregate figures, the Burdekin region — Queensland’s most productive sugarcane region, explored elsewhere in this series — shows the most direct evidence of practice change translating into measurable outcomes. The Burdekin region recorded the most significant improvement in dissolved inorganic nitrogen, achieved through adopting practices that reduced the nitrogen surplus in sugarcane and improved mill mud application. The Burdekin catchment had the greatest annual reduction, at 3 per cent, with reductions mostly due to improved nitrogen fertiliser management and mill mud application in the sugarcane industry.

Key programs contributing to improved water quality from sugarcane lands include the Queensland Government’s Smartcane BMP program, which reported 19,228 hectares of sugarcane management practice improvements; the Australian Government’s Reef Trust Partnership Reef Alliance Project Phase 2, which reported 13,062 hectares of sugarcane management practice improvements; Project Catalyst, which reported 39,941 hectares of sugarcane management practice improvements; and the Reef Trust Reverse Tender Program, which reported 9,309 hectares of sugarcane land with reduced nitrogen application rates.

The earlier Report Card for 2019–2020 offered more encouragement: modelling showed moderate progress towards the dissolved inorganic nitrogen target with an annual reduction of 2.2 per cent, with the greatest reductions in the Wet Tropics at 3.2 per cent and the Burdekin at 2.8 per cent. Those reductions were mostly attributed to improved nitrogen fertiliser management and mill mud application in the sugarcane industry.

The variation between reporting periods reflects the challenge of incremental practice change operating within natural climate variability. Wet years flush more pollutants. Dry years suppress run-off but may mask underlying practice levels. The Reef 2050 Water Quality Improvement Plan itself identified in 2017 that changes in on-ground management and improvements to program design were an urgent need, with concerns expressed about the progress made to date towards water quality targets and calls made for acceleration of approaches to ensure that long-term targets could be met.

THE HUMAN DIMENSION: UPTAKE, RESISTANCE, CULTURE.

Behind the aggregate hectares and percentage reductions lies a more textured reality: individual farming families making decisions about their land, their livelihoods and their relationship to an ecosystem that most of them live beside and value. The social dimensions of practice change — what drives adoption, what inhibits it — are as consequential as the agronomic and regulatory ones.

The Cane Changer project drew on principles of psychology and human behaviour to better understand growers and help increase farmers’ adoption of best management farming practices known to improve water quality through the Smartcane BMP program. Practice change is understood as a journey that farmers take over time, either guided by extension officers and other advisers or on their own. The Reef 2050 Water Quality Improvement Plan includes specific consideration of the human dimensions that influence practice change and deliver water quality outcomes. Human dimensions are the social, economic, institutional, environmental and cultural factors and attitudes that motivate — or obstruct — landholders to make changes.

Landholder adoption of management practices and technologies that reduce the risk of poor water quality is less likely to be widely adopted and maintained where there are perceived risks to farm profitability. Economic information is therefore needed to influence these perceptions and can be used to help accelerate management practice adoption.

The stories emerging from growers who have moved through the Smartcane BMP process suggest that the framing of the program matters — that its value to growers is most legible when described in terms of farm-level benefit rather than regulatory compliance. Many growers who have completed accreditation describe the process as generating useful information about their own operations, not merely satisfying an external requirement. Combining both economic and water quality information can identify opportunities to improve both water quality and grower profitability, ensuring the cost-effective use of Reef 2050 Plan investments and helping maintain the sustainability of the Queensland sugarcane industry and the regional communities it supports.

The investment has been substantial on the public side. $614 million in Australian and Queensland government funding was committed for Reef 2050 Water Quality Improvement Plan actions from 2017 to 2022. Both governments have boosted their funding commitments further, with $945 million committed to improve Reef water quality and accelerate progress towards water quality targets — taking total water quality investment committed to close to $1.8 billion to 2030.

REEF-COMPATIBLE: A STANDARD STILL BEING EARNED.

The question with which this essay began — can cane farming become reef-compatible? — does not resolve neatly. The evidence from a decade of concerted effort suggests: partially, and unevenly, and not yet at the pace the science demands.

The progress is real. Hundreds of thousands of hectares have moved toward practice standards that demonstrably reduce nitrogen loss. Progress recorded in the Reef Water Quality Report Cards is mainly due to streambank repair projects, improved grazing land management, and changes in sugarcane practices that improve nitrogen fertiliser management. Growers in parts of the Burdekin and Wet Tropics regions have reduced fertiliser application rates while maintaining productivity, proving that the agronomic case for change is sound. The Smartcane BMP framework has grown to cover roughly 45 per cent of the cane area and has created a credible, third-party verified standard that both industry and government can point to.

But the water quality targets remain largely unmet. The results of water quality target reviews indicate that regional approaches are essential to achieving Reef-wide ecological outcomes. In areas with high anthropogenic loads such as the Wet Tropics and Burdekin, which are typical of highly modified catchments, substantial reductions in dissolved inorganic nitrogen, fine sediment and particulate nutrients are necessary to meet marine ecological thresholds. The dissolved inorganic nitrogen target set under the Reef 2050 framework calls for a 60 per cent reduction. The reductions achieved to date, while meaningful at the catchment level, remain a fraction of what is required.

Many practice change projects do not make their results publicly available, limiting the ability to learn what works — a constraint that slows the accumulation of shared knowledge across an industry that is, farm by farm, working through a common problem.

Reef-compatible sugarcane farming is not an impossible destination. The agronomy exists. The technology is advancing. The regulatory framework, whatever its tensions, has established minimum practice standards that represent a genuine floor below which nitrogen and pesticide management cannot fall. The accreditation architecture gives growers a pathway and a credential. The market is beginning to reward that credential. And the science — updated, refined and increasingly precise in its attribution of catchment-specific loads — continues to clarify exactly what change is needed and where.

What remains is the scale and pace of adoption, and the durability of commitments made not under ideal conditions but under the economic pressures, weather variability and institutional complexity that characterise real farming in Queensland’s coastal catchments. The negotiation is not concluded. It is ongoing. And it is conducted, season by season, in the gap between where the industry is and where the Reef needs it to be.

The permanent civic identity of the Queensland sugarcane industry — anchored at sugar.queensland as part of Queensland’s onchain institutional layer — carries within it precisely this dual accountability: to an industry that has shaped the state’s landscape and regional economies for over a century, and to a reef that has defined Queensland’s relationship with the natural world for far longer. That both belong to the same record is not incidental. It is the whole point.