Denim is undeniably a wardrobe essential. It’s also a cultural cornerstone, and a $70 billion global industry. Yet, the story of our beloved jeans is far from simple. Behind the durability and versatility lies a significant environmental and ethical challenge. The production process of denim continues to raise questions of sustainability.

Denim production begins with cotton, a crop notorious for its environmental demands. You can view this article or this article for more information if you’re curious, but I’ll still give a brief overview. A single pair of jeans requires 3,781 litres of water, according to the UN’s Environment Programme. Much of this cultivation occurs in water-scarce regions, where irrigation often drains local resources. The Aral Sea crisis is a striking example of this impact, with large-scale cotton farming turning what was once the world’s fourth-largest lake into a desert. Add in the extensive use of pesticides and fertilisers, and cotton farming contributes significantly to soil degradation and water pollution.

Once the cotton is harvested, it moves to the dyeing and finishing stages—critical parts of the process that create denim’s signature colour. Historically, natural indigo derived from plants was used, but modern denim relies on synthetic dyes, which can be more harmful. Factories often discharge untreated dye effluents into rivers, turning waterways blue and exposing aquatic ecosystems to toxic chemicals. The Citarum River in Indonesia, one of the world’s most polluted rivers, is home to several textile factories producing denim for fast fashion brands, and exemplifies the devastating consequences.

The distressing of denim—creating the faded, ripped, or vintage look so in demand—is another ecological hurdle. Techniques like sandblasting, stone washing, and chemical treatments consume enormous amounts of water and energy. Sandblasting has been linked to silicosis, a deadly lung disease, putting factory workers at severe health risk.

But the denim dilemma doesn’t end with production. The rise of fast fashion has accelerated consumption, leading to an overabundance of cheap jeans. In the UK alone, 300,000 tonnes of old clothes are thrown away each year. That’s an estimated £140 million worth of clothing in a landfill. Synthetic blends, now common in stretch denim, complicate recycling efforts as they’re harder to separate and process. Even natural fibre jeans rarely get recycled; they are often downcycled into insulation or industrial rags, extending their life cycle but not fully addressing waste.

What makes this dilemma even more pressing is the paradox of denim’s longevity. Jeans are designed to last—they’re durable, timeless, and versatile. Yet consumer habits favour frequent purchases, driven by trends and the low cost of fast fashion. On average, Americans own seven pairs of jeans but regularly wear only four, according to a report by Cotton Incorporated. This disconnect between durability and disposability reflects broader challenges in the fashion industry’s sustainability journey.

Efforts to tackle the denim dilemma are underway, but progress is uneven. Brands like Levi’s, Nudie Jeans, and Everlane have pioneered water-saving techniques and ethical labour practices. Levi’s Water<Less technology claims to reduce water use by up to 96% in some styles, while Nudie offers free repairs and promotes second-hand sales. However, these initiatives remain exceptions rather than the norm, often confined to premium collections out of reach for many consumers.

Emerging technologies hold promise. Innovations in dyeing, such as foam-dyeing technology, significantly reduce water and chemical use. Laser treatments can replace water-intensive distressing methods, and bioengineered indigo is being explored to cut reliance on harmful synthetic dyes. These advancements could revolutionise denim production, but scaling them across the global supply chain is a monumental challenge.

From a consumer perspective, the choices are equally complex. Buying second-hand, opting for higher-quality jeans designed to last, or supporting brands with transparent practices can make a difference. However, these actions often require time, money, and access—privileges not universally available. The growing popularity of resale platforms like Depop and Vinted offers hope, normalising second-hand shopping and giving denim a longer life.

The denim dilemma encapsulates the tensions at the heart of sustainable fashion: balancing economic realities with environmental and ethical responsibilities. While the road ahead is fraught with challenges, the resilience of denim itself offers a metaphor for the industry’s potential to adapt.