Harris died at his home in New Road, Oxford in June 1840. Harris came to Oxford as a journeyman carpenter and rose to become Governor of Oxford Castle and Prison from 1786 until 1809. He developed a contracting business with convict labour, supplemented by hiring wage-earning tradesmen.
Harris became involved in waterway engineering, starting by being the contractor to extend the Oxford Canal in Oxford from Hayfield Road to Worcester Street and build the Worcester Street wharves 1788-1789.
He built four pound locks to replace flash locks, the first being Osney Lock for the Thames Navigation Commission in 1790. In central Oxford the Oxford Canal and the River Thames were originally linked by a flash lock at Hythe Bridge.
In 1795-1797, Harris replaced it with Isis Lock, a broad lock to allow Thames barges in and out of the Oxford Canal Company"s Worcester Street wharves. None of Harris"s pound locks survives in the form in which he built them.
The Oxford Canal rebuilt Isis Lock as a narrow lock in 1844, and all of his Thames locks have been either rebuilt or replaced.