In the early 20th century, one of England’s most remarkable architectural rescue operations took place in conditions that would challenge even modern engineers. Winchester Cathedral, whose cornerstone was laid in 1079 and whose construction developed over several centuries, had begun suffering serious foundation problems by the beginning of the 1900s. The cathedral stood on ground containing peat and other unstable materials near the River Itchen, and centuries of changing groundwater levels had contributed to the deterioration of its timber foundations. By 1904, cracks had appeared in the building, raising fears that the enormous medieval structure could eventually collapse. The solution would require an extraordinary combination of engineering, construction and underwater diving—and a diver named William Walker would become central to the effort.
The fundamental problem was hidden beneath the cathedral. Parts of Winchester Cathedral’s foundations rested in ground affected by water, while the crypt beneath the nave was partly below the water table and could flood during periods of heavy rain. Over time, fluctuations in water levels contributed to the decay of wooden foundation materials and compression of the peat beneath the structure.
