GENEVA — A Chatham House research paper published Dec. 19 says the water footprint of global food and agriculture trade is expanding and calls for mandatory disclosure, stronger supply-chain due diligence and more cooperation at the World Trade Organization. The authors argue that water risks embedded in “virtual water” trade are largely invisible to consumers and investors, leaving importing economies exposed to shocks and exporting regions vulnerable to depletion and pollution, Dec. 27, 2025.
Water footprint disclosure moves from niche metric to trade risk
The report says food systems account for almost 70% of global freshwater withdrawals, and international trade shifts part of that burden across borders through the water embedded in crops, feed and processed foods. It warns that while trade can help water-scarce countries meet demand, it can also pull production toward regions where water is underpriced, regulation is weak and drought risk is rising.
In the paper’s definition, a water footprint goes beyond irrigation to include rainwater used in production and the water required to dilute pollution. “This situation is increasingly unsustainable, requiring major reform of food systems, agriculture and trade,” it says.
The authors recommend that importing markets treat water footprint exposure as a supplier risk that should be measured, disclosed and managed. They argue that consistent water footprint data would help retailers, investors and governments identify hotspots, support more resilient sourcing, and reduce the chance that scarcity in one basin ripples through global supply chains.
Due diligence: tracking the water footprint from farm to shelf
Turning measurement into accountability means specifying what companies must report and how far down the chain they must look. A Chatham House chapter on importer-country initiatives says governments can “mandate supply chain transparency and due diligence,” including disclosure of the water footprint of supply chains, to help buyers identify sourcing areas where export production may compete with local drinking water, sanitation and ecosystems.
That chapter cites a Global Commission on the Economics of Water call for disclosure, describing water footprint information as “key to steering capital and consumer preferences in favour of sustainable practices.”
New data suggest the stakes are not distributed evenly. A UN University Institute for Water, Environment and Health report released in August said 75% of people in high-income countries and 62% in low-income countries experience reduced water scarcity linked to food trade, but 22% and 37%, respectively, experience increased scarcity, with poorer communities least able to cope with water footprint shocks.
WTO action: making water footprint rules trade-compatible
Mandates can collide with trade politics if exporters see them as hidden barriers. A Geneva Trade Week 2025 roundtable on the water footprints of traded goods — organized by TESS, Chatham House and the Global Commission — included a World Trade Organization counsellor and focused on how trade cooperation could reduce water-related supply-chain risks while avoiding disputes over new sustainability requirements.
The WTO has also shown it can move on environmental rules when members align. The organization said its Agreement on Fisheries Subsidies entered into force Sept. 15, creating binding disciplines and new transparency obligations. Analysts point to that model when arguing for coordinated approaches to water footprint disclosure and due diligence that limit fragmentation and reduce the risk of conflicting national rules.
A long-running debate, now with sharper stakes
Research on the water footprint of trade has been building for decades. A 2004 Water Footprint Network report estimated that a significant share of global water use supported exports, while a 2008 essay, “The water footprint of food,” by water scholar Arjen Hoekstra described food trade as trade in water “in virtual form.” A 2011 Water Resources Research paper mapped the global virtual water trade network and found that a relatively small share of trade links carried a large share of embodied flows.
What is changing now is the push to make water footprint data decision-grade: comparable across suppliers and usable in contracts, financing and trade policy. Without shared expectations, the report’s authors warn, disclosure and due diligence could splinter into a patchwork — and the hidden water footprint of the global food basket will keep growing.
