The 1830 canal extension to Turf completely bypassed Topsham Quay and did not please Topsham businessmen.

Robert Davy, a prominent local shipbuilder and businessman, took Exeter City Chamber to court. He won, and the city was forced to contribute £13,000 towards a new canal entrance directly opposite his Passage shipyard in Topsham. Robert Davy supplied the stone at a personal cost of £800, and Topsham Lock opened in 1832.

Unlike Turf and Double Locks, the Topsham lock-keeper’s cottage was not set up as an inn. It had an upstairs bedroom and a ground-floor kitchen/living room that flooded in winter. There was no water or power until 1947. The lock-keeper’s family had to collect water from a Topsham pump and take it across the river in a bucket. In summer, they supplemented their income by netting whitebait in the lock.

Robert Howard kept the lock from 1881 to 1923 and was succeeded by his daughter Mary from 1923 to 1948. Topsham lock was closed and sealed in 1976.