Cleveland Salt Company â€“ Vulcan Street
In 1859 a borehole was started at Bolkow and Vaughansâ€™ Middlesbrough Ironworks in search of a clean water supply for use in their boilers, instead of dirty water from the Tees. By 1862 at a depth of 1200ft a bed of rock salt was discovered that was almost 100ft thick.
The Cleveland Salt Company was formed in 1887 to exploit this resource for the fledgling chemical industry, Carl Bolckow nephew of Henry was one of the first board members, fresh water was pumped down into the salt bed which it dissolved, brine was then pumped out and evaporated in large pans to drive off the water and extract the salt.
The six original pans were initially fired by waste hot gas from the Middlesbrough Ironworks blast furnaces, this was expanded to thirteen pans in 1889. In 1920 the blast furnaces were blown out and the pans had to be converted to run on coal.
A total of four wells existed in the companiesâ€™ lifetime, The original No.1 was abandoned in 1893 due to a roof fall, No.2 and No.3 from 1888 and 1893 respectively operated until around 1938 when they started to become choked. So No.4 which had been an incomplete well started in 1896 was re-started, but was not completed until 1941 due to drilling problems and the outbreak of the Second World War.
In 1945 and 1946 there were roof falls in the remaining No.4 well after which the evaporation pans were never restarted. The company wound up in 1947 having produced 879,972 ton of salt in 59 years.
Making a few calculations that suggests a volume of over 400,000 cubic meters, or 165 Olympic Swimming Pools. Itâ€™s an interesting thought that there must now remain a huge water-filled void under the area, most likely under the river and Transporter Bridge !
Today all that remains is the impressive red brick boundary wall on Vulcan Street dating from 1887. This became a listed building in 1988, however itâ€™s not totally original as it was rebuilt from other interesting sections of the original building by the Cleveland Community Task Force, Middlesbrough Council and the Davy Corporation in 1982.