The
Grand Junction Canal was authorised by an
Act of Parliament on 30 April 1793, and was to run over from
Braunston on the
Oxford Canal to
Brentford near
London, where it would join the
River Thames. Construction of the northern section, which included the Whilton locks at Buckby, was complicated by the need for two tunnels, one to the north of the locks near
Braunston, which was long, and the other to the south at
Blisworth, which was long. Despite encountering quicksands in Braunston Tunnel, it was finished on 21 June 1796, and the canal opened to
Weedon Bec, around to the south of the locks. Shortly afterwards, it was extended further south to Blisworth, but there were serious problems with Blisworth Tunnel, which had failed in January 1796.
William Jessop was the engineer and wanted to abandon the idea of a tunnel. He proposed to build 29 locks to get beyond Blisworth, but was persuaded to try a different alignment by three engineers who were brought in to advise. Low level headings were cut to drain the main workings of water, and the tunnel opened on 25 March 1805, the last part of the canal to be completed. The Grand Junction Canal became part of the Grand Union Canal in 1929, following amalgamation with the
Regents Canal, the Warwick and Birmingham Canal and the Warwich and Napton Canal. Below the bottom lock was a long level pound stretching to beyond Blisworth Tunnel. The seven locks raised the level of the canal by to a fairly short summit pound, which passed through Braunston Tunnel and then descended through five locks to Braunston. The locks were built wide enough to take two narrow boats side by side, in the hope that the canals beyond the northern terminus could be persuaded to widen their locks and that wide barges carrying 70 tons could be operated. The Grand Junction Canal experimented with side ponds from the early 1800s. The locks at Bourne End had several radial ponds, but use of the ponds was abandoned because it took too long to use the lock. Those at Buckby had two rectangular side ponds per lock, at different levels, and this design was eventually installed at most locks between Buckby and lock 45 at Bulbourne, the junction with the
Wendover Arm. ==Location==