The building of the Thames & Severn Canal took place with great speed. The section as far as Chalford opened in 1785. The first barge to travel the length of the canal reached the Thames at Lechlade on 19th November 1789. To finance the work, the Company borrowed an additional £120,000, raising the total spent to around a quarter of a million pounds. Just like the Stroudwater, twice as much as the original estimate.

The headquarters of the Thames & Severn was located at Brimscombe Port - about two miles from the junction with the Stroudwater at Wallbridge. Coal was stored on the island between the arms of the canal to make pilfering more difficult.