The first improvement of the lower river was at Newark, where the channel splits into two. The residents of the town wanted to increase the use of the branch nearest to them, and so an Act of Parliament was obtained in 1772 to authorise the work. Newark Navigation Commissioners were created, with powers to borrow money to fund the construction of two locks, and to charge tolls for boats using them. The work was completed by October 1773, and the separate tolls remained in force until 1783, when they were replaced by a one-shilling (5p) toll whichever channel the boats used.