Blackwall Rock

The Blackwall Rock was a reef in the River Thames in East London. The rock provided a useful shelter for moored vessels, but also proved a hazardous obstruction to river navigation. It was removed in the early 19th century following the opening of the adjacent West India Docks.

Blackwall Rock was located a short distance upriver of Blackwall Stairs, the southern end of a causeway from Poplar High Street which crossed extensive marshland, between the entrances of the West and East India Docks. The rock was always a hazard to river traffic, as it sometimes lay less than 3 feet below the surface at low tide. The entrance to the West India Docks, just to the south-west of the rock, was substantially obstructed by the reef upon the docks' opening in 1802. In 1803, in his Strictures on the Alarming Progress of the Blackwall Rock in the River Thames, Robert Edington wrote that he surveyed the rock under the direction of the Corporation of the City of London's harbourmaster, Captain John Raymond Snow. Prior to his survey, Edington was under the impression that the rock was 40 by 30 feet ; Abraham Rees's Cyclopædia, published shortly before Edington's survey, had given these measurements. Rees asserted that newspaper reports of one of Thomas Boddington's West Indiaman vessels being wrecked on the rock were incorrect, and that the relatively recent installation of piling and booms prevented ships from coming near the reef.

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