Grantham Canal is a canal that runs 33 miles (53 km) from Grantham through 18 locks to West Bridgford where it joins the River Trent. It was built primarily to allow for the transportation of coal to Grantham.
After a survey carried out by William Jessop in the summer of 1791, a bill was put to Parliament in 1792 but was rejected. A revised route was developed, with the junction now at West Bridgford. A second bill was put forward and received the Royal Assent on 30 April 1793. Building work on the canal started in 1793, with Jessop in overall charge, but with James Green and William King as resident engineers: Green was appointed engineer for the section of canal from the Trent to the Leicestershire border, and Kind from there to Grantham.
The act authorised an initial £75,000 to be raised to pay for construction, together with an option to raise a further of £30,000, of which £20,000 should be raised by shares of £100 each among the initial subscribers, and £10,000 by mortgaging the future income of the canal. However, this amount proved insufficient, and there was also disagreement between the shareholders as to their liability to raise the additional £20,000. As a result a second act was sought. This received the Royal Assent on 3 March 1797, and made clear the obligations of existing shareholders to pay the extra subscription, and also authorised an additional £24,000 to be raised. The second act also removed restrictions in the first act, and allowed the company to set whatever rates it chose for using the canal.
The eastern section from the Leicestershire border was opened on 1 February 1797, with the rest of the canal later that year. The canal was built with locks 75 feet by 14 feet (22.9 metres by 4.3 metres), the same size as those on the Nottingham Canal to allow boats to use both. The branch to Bingham authorised by the first act was not built.
The Grantham Canal Restoration Society was formed in the early 1970s. Together with British Waterways, the Inland Waterways Association and the Waterway Recovery Group, the Society began the work of restoration of the canal to navigation, a process which is still ongoing. Following the restoration of the three locks at Woolsthorpe in the 1990s, a 10-mile (16-kilometre) section from the A1 to Redmile will be completed once the four locks at Stenwith are restored. The Polser Brook Aqueduct was restored in 2003, and five locks have so far been restored. The railway embankment at Woolsthorpe which blocked the canal has been removed. Approximately one quarter of the canal is now to navigable standard, and much improvement of the towpath has taken place.
At this time the two major challenges are relinking the canal to the River Trent and the final route into Grantham. The original route to the Trent has a number of low bridges, notably A52: there are practical proposals for alternative new cuts, though these pose additional problems in finding funding, since they are not restoration. At Grantham, the A1 embankment blocks the line of the canal, and the terminal basin has been filled in: there are plans for a tunnel under the A1 as part of a cycle route to improve access to Grantham, and the basin could be redeveloped in due course.
There is also a 5-mile (8-kilometre) dry section between Cotgrave and Kinoulton, which has presented problems since construction in the 18th century: gypsum in the soil reacted with the waterproof clay leading to leaking. Following closure, this section then became colonised by an invasive shrub.
In early 2005, British Waterways appointed a full-time Grantham Canal restoration manager, Kevin Mann, for an initial 18-month trial period. He will be responsible for planning and managing funding schemes for the restoration, identifying development opportunities and the promotion and interpretation of the canal.
