When the Eastern Union Railway announced plans for an extension from Ipswich to Stowmarket in 1844, the Trustees negotiated with the company to lease their canal. They hoped that this would be of benefit to the shareholders, and that it would help the railway by removing one source of opposition to their plans. They submitted a firm proposal for the lease on 8 February 1845, to which the railway agreed, and the shareholders sanctioned the action soon afterwards. They engaged a Parliamentary agent to handle the details, who realised that the original Act of Parliament, dating from 1790, expressly prohibited the Trustees from leasing the canal. By September, the two sides had agreed that each of them would seek to obtain powers to overturn the clause. The railway company would pay £1,070 per year for the first 21 years, and £850 per year for the second 21 years. The Trustees sought an Act of Parliament to authorise this, which contained a clause requiring the railway company to maintain the navigation. The House of Lords were not convinced that the clause was strong enough, and amended it to ensure that the railway had to maintain it "in as good a state and condition as the same shall be at the time of passing of the Act." With this amendment in place, the Act was passed on 26 June 1846.