While in Europe the clash between forestry and conservation plays out in modern subsidy schemes and courtrooms, Asia is facing another dramatic battle to save one of the wonders of the world. In India, the drying-up of the Yamuna river now poses a serious threat to the Taj Mahal’s historic timber foundations, forcing scientists and engineers to search for urgent solutions. What has happened, and how is India’s ecological crisis endangering this unique 17th-century architectural monument?
How does timber hold up the Taj Mahal?
The Taj Mahal was built between 1632 and 1653, not on solid bedrock but on a complex system of timber wells and piles sunk into the sandy floodplain of the Yamuna.
Engineers of the Mughal Empire created a dense grid of wells along the riverbank, filled with stone and lime mortar to distribute the mausoleum’s immense weight. Massive timber posts and beams hold the whole structure together.
Timber can survive for centuries only because it lies deep underwater; in an oxygen-free environment, micro-organisms cannot trigger decay – the very mechanism that has kept Venice’s palaces standing for centuries. Although the exact species used remains a matter of debate among researchers, since the foundations have never been fully excavated, Indian historical records most often cite ebony, while other sources point to Shorea robusta. Both species require constant moisture to retain their structural strength and to avoid cracking or shrinking.
The ecological crisis: a drying Yamuna
Modern climate change, dams built upstream, industrial pollution and water extraction for urban needs have dramatically lowered water levels in the Yamuna. In summer the river around Agra all but dries up, exposing its bed. As a result, groundwater levels directly beneath the Taj Mahal are falling fast. “The timber needs the constant moisture provided by the river’s water,” warns Ram Shankar Katheria, a former member of parliament for Agra. Once the water retreats and the timber foundations come into contact with oxygen, an irreversible process of rot and decay begins.
The concern is compounded by the fact that in recent years the first cracks have appeared in the mausoleum’s walls and surrounding arches. As far back as 2011, India’s Supreme Court ordered enhanced monitoring of the Taj Mahal’s four minarets, amid suspicion that they had begun to tilt imperceptibly.
Modern technology and rescue plans
To save the 73-metre mausoleum, the Archaeological Survey of India is deploying state-of-the-art technology in partnership with international collaborators, including the DHARMA lab at the University of Notre Dame in the United States.
Engineers carry out regular digital documentation of the structure and use electromagnetic sensors to detect internal movement and changes in moisture within the masonry, before cracks ever reach the surface of the white Makrana marble.
Former Agra mayor Naveen Jain and other experts are pressing India’s central government to build a dedicated hydraulic installation on the river. Its purpose would be to artificially maintain a constant, high water level around the Taj Mahal all year round, ensuring the timber foundations never come into contact with air.
Alongside the fight against subsidence, restorers are also battling the wear caused by air pollution and the constant, enormous crowds of tourists. To remove yellowish smog stains from the marble without abrasive scrubbing, a special medicinal clay paste is applied. A strict zero-emission transport zone has also been established around the monument, along with tight restrictions on visitor movement.
The Taj Mahal’s fate shows that even humanity’s mightiest architectural monuments remain entirely dependent on nature’s balance. The ancient engineers built the mausoleum in symbiosis with the river, unable to foresee modern-day industrialisation and the drying of rivers. Unless the Yamuna is saved and its water levels restored, the decay of the timber foundations could mark the beginning of the end for this wonder of the world.