In 1899 Brunner (who had by then been created a baronet) became chairman of the Runcorn and Widnes Transporter Bridge Company. He subscribed £25,000 (£ in ) towards its construction plus a loan of £12,000 (£ in ) together with a personal guarantee on a bank loan of £31,000 (£ in ). When the building of the bridge was complete in 1905 it was due to be opened by Edward VII, but the king was unable to attend, and so Brunner performed the ceremony himself. By 1911 it had become apparent that the bridge would always operate at a loss, and Brunner assigned his interest in it to Widnes Corporation. "The Times" stated that this action amounted to a "virtual gift of £68,000" (£ in ).