trade on the lower river was carried in barges and keels. during the early 1800s as trade was increasing, so the river was simultaneously silting up. around 1800, vessels carrying 60 tons could reach the port facilities at spalding; however, by the 1820s, ships could only be loaded with 40 tons each as the river silting had worsened. trade records indicate that in 1829, vessels carried just under 20,000 tons to and from spalding, and by 1835 this had increased to over 34,000 tons. there was pressure from merchants to cater for larger vessels, and with later improvements, carried out under an act of parliament obtained in 1837, barges and sloops of up to 120 tons could use the port. because the river was maintained for drainage, some commercial traffic continued despite the railways, and tolls of £478 were collected on 11,690 tons in 1888. coal for spalding gasworks arrived by boat until the early 1900s, and the last regular trade was the carriage of corn, hay and straw from spalding to fosdyke, where the cargo was transferred to larger ships. all commercial carrying had ceased by the end of the second world war.