Salt in Cheshire

Cheshire is a county in North West England. Rock salt was laid down in this region some 220 million years ago, during the Triassic period. Seawater moved inland from an open sea, creating a chain of shallow salt marshes across what is today the Cheshire basin. As the marshes evaporated, deep deposits of rock salt were formed.

A settlement, Condate, was built during Roman times at the current location of Northwich. It is believed that the Romans built this settlement due to the strategic river crossing of the Weaver and the presence of the brine springs. The Romans used lead salt pans to extract the salt from the brine. Salt pans and first-century brine kilns have both been found around the Roman fort.

The salt beds beneath Northwich were re-discovered in the 1670 by employees of the local Smith-Barry family. The family were actually looking for coal when they accidentally discovered rock salt in the grounds of their house, Marbury Hall, Marbury, north of Northwich with salt extraction starting shortly afterwards. Salt was also extracted in the area immediately north east of Northwich, including the villages of Marston (including the Lion Salt Works) and Wincham (including the New Cheshire Salt Works).

In the 19th century it became uneconomical to mine salt, and so solvent extraction using water as a solvent was used. Hot water was pumped through the mines that dissolved the salt and the resultant brine was pumped out and the salt extracted from the brine. This technique was known as wild brine pumping or natural brine pumping but weakened mines and led to land subsidence as mines collapsed. The collapse of a number of mines led to salt mining to move to Winsford.

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