As US trade negotiations intensify, domestic phosphorus recovery offers an overlooked path to resource security
New Zealand is in active negotiations with the United States over critical minerals—a development that could reshape our resource sector. But while attention focuses on traditional mining, a significant opportunity may lie in an unexpected place: recovering essential nutrients from waste streams we currently send to landfill.
The US Critical Minerals Push
On January 14, US President issued a proclamation requiring trading partners to sign critical minerals agreements within 180 days or face tariffs. The move reflects growing concern about US dependence on foreign sources—particularly China—for minerals essential to defence systems, clean energy technology, and advanced manufacturing.
New Zealand has responded. The Ministry of Foreign Affairs has confirmed the government is "in discussions with the United States regarding a non-binding critical minerals framework," with officials providing advice to ministers and an announcement expected soon.
Australia has already signed a framework agreement with the US, including an US$8.5 billion investment pipeline and commitments on price support mechanisms for priority minerals. New Zealand's negotiations follow a similar template.
What New Zealand Has to Offer
In January 2025, MBIE published New Zealand's first Critical Minerals List, identifying 37 minerals essential to our economy and potentially valuable to international partners.
Two stand out for their agricultural significance:
Phosphate is used in fertiliser production and battery storage applications. It appears on the European Union's critical minerals list. Importantly, New Zealand is identified as a "potential future producer"—meaning we have untapped capacity.
Potassium (Potash) is the other essential fertiliser component. Listed on Canada's critical minerals register, it's a mineral New Zealand relies on but does not currently produce, with "low/no known potential" through conventional extraction.
The Case for Waste-to-Resource Recovery
Globally, a shift is underway in how nations think about phosphorus security. Rather than relying solely on mined phosphate rock—a finite resource concentrated in just a handful of countries—leading economies are investing in recovery from wastewater and organic waste.
The science is well-established. Phosphorus recovery from wastewater treatment can achieve efficiencies of 50-95% depending on the technology deployed. First-generation facilities typically recover 10-20% of available phosphorus, while advanced systems using thermal hydrolysis or sewage sludge ash processing push recovery rates significantly higher.
Switzerland has mandated complete phosphorus recovery from municipal wastewater by 2026. Germany has binding targets taking effect in 2029. Japan, with virtually no domestic phosphate deposits, has legislated wastewater recovery as a national priority.
New Zealand, by contrast, sends much of this material to landfill.
The Strategic Opportunity
The global fertiliser market exceeds US$200 billion annually. New Zealand imports the majority of its phosphate and potash requirements, creating both cost exposure and supply chain vulnerability.
Domestic recovery addresses multiple objectives simultaneously. It reduces import dependence for essential agricultural inputs. It diverts organic waste from landfill, reducing emissions and disposal costs. It creates value from material currently treated as a liability. And it positions New Zealand as a contributor to critical mineral supply chains—potentially relevant to the US negotiations now underway.
Companies like Alimentary Systems Limited (ASL) are already developing this capability in New Zealand. Their approach transforms organic waste streams—including biosolids from wastewater treatment—into agricultural products designed to improve soil health and crop resilience. Financial projections show fertiliser revenue becoming a significant component of their business model as operations scale.
ASL has signed a memorandum of understanding with Fertilizer New Zealand Limited to commercialise these products, with field trials planned and product testing underway at Otago University..
Implications for Policy and Investment
The timing is significant. With US negotiations active and global attention on supply chain resilience, New Zealand has an opportunity to develop waste-to-resource infrastructure that serves both domestic agricultural needs and international strategic interests.
This doesn't replace traditional mining opportunities identified in the Critical Minerals List. But it does offer a complementary pathway—one that aligns with circular economy principles, reduces environmental impact, and builds sovereign capability in essential nutrients.
The minerals beneath our feet matter. So too do the nutrients already circulating through our economy, waiting to be recovered.
Key Points:
- New Zealand is negotiating a critical minerals framework with the United States
- Phosphate is on NZ's Critical Minerals List with potential for domestic production
- Global leaders are mandating phosphorus recovery from wastewater
- Domestic companies are developing waste-to-fertiliser technology
- Recovery infrastructure could serve both agricultural security and trade objectives
References:
- Ministry of Business, Innovation and Employment: A Critical Minerals List for New Zealand (January 2025)
- Ministry of Foreign Affairs and Trade: NZ-US Critical Minerals Framework Discussions (January 2026)
- New Zealand Herald: "New Zealand, United States in discussions over critical minerals framework" (30 January 2026)