Grand Sluice And Bridge And Lights

The Grand Sluice, bridge, and lights in Boston were constructed between 1764 and 1766, with alterations made in 1883 and the 20th century. Designed by John Grundy and Langley Edwards, with modifications by John Williams, the structure is made from gritstone, red brick, blue brick, concrete, and steel. It features three channels on the west side and a wider channel with a lock on the east bank to allow boats to pass through.

On the south side, the river's west wall and two cutwaters are original 18th-century gritstone, while the eastern cutwater has been adapted and partially rebuilt in blue brick during the 1883 renovations. The north side has been extended to create a lock mooring platform, and the cutwaters there have been partly rebuilt in concrete. The seaward doors are hydraulically operated iron-bound timber doors, and on the landward side, the three channels have pulley-operated drop doors managed from a steel gantry. The navigable channel includes two sets of lock gates.

The road bridge is constructed of red brick and features four segmental arches that now support a 20th-century concrete bridge top with iron railings. At each corner, there are diagonally set, circa 1930s panelled ashlar piers with moulded plinths and cornices, which bear openwork painted iron supports that hold four elongated decorative pendants for lantern lights.

The construction of the Grand Sluice required an Act of Parliament and marked the first significant expansion of the town since the Middle Ages. A stone on the eastern bank wall commemorates the lock's opening by Edmund Turner Esq. on December 8, 1883, with John Evelyn Williams as the engineer and William Rigby as the contractor.