Exeter Canal

The Exeter Ship Canal, also known as the Exeter Canal, downstream of Exeter, Devon, England. It was built in the 1560s which means it pre-dates the "canal mania" period and is one of the oldest artificial waterways in the UK.

At the start of Exeter's history, the River Exe was tidal and navigable up to the city walls enabling it to be a busy port. In the 1270s or 80s, the Countess of Devon, Isabella de Fortibus, built a weir across the river to power her mills (this weir is remembered in the name of the nearby suburb Countess Wear). This had the effect of cutting off Exeter's port from the sea and damaging its salmon fisheries. In 1290, trade with Exeter's port was restored, only to be blocked by a new weir built in 1317 by Hugh de Courtenay, 9th Earl of Devon (Isabella's cousin), who also built a quay at Topsham. Because of the blockages on the river, boats were forced to unload at Topsham and the earls were able to exact large tolls to transport goods to Exeter. For the next 250 years the city petitioned the King to have the waterway reopened, to no avail, until 1550 when Edward VI finally granted permission. However it was by then too late because the river channel had silted up.

In 1563, Exeter traders employed John Trew of Glamorgan to build a canal to bypass the weirs and rejoin the River Exe in the centre of the city where a quay would be built. Work began in February 1564, and was completed in Autumn 1566 or early 1567. The canal had three locks with vertical gates – the first pound locks to be built in Britain. They accommodated boats up to 16 tonnes. The original cut was 3 feet (0.91 m) deep and 16 feet (4.9 m) wide (0.9 m by 5 m). It ran one and three quarter miles (2.8 km) from just below the Countess Weir to the centre of Exeter. This navigation was not very effective; it could not be entered at all states of the tide, and the double transfer of cargo over such a short distance made it uncompetitive with road transport. The weir that maintains the water level in the quay is still named "Trew's Weir" after the canal's builder.

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