The Louth Navigation was a canalisation of the River Lud. It ran for 11 miles (18 km) from Louth in Lincolnshire, England, to Tetney Haven, at the mouth of the Humber. It was authorised by act of Parliament in 1763 and completed in 1770, under the supervision of the engineer John Grundy Jr. and then by James Hoggard. Eight locks were required to overcome the difference in altitude, six of which were constructed with sides consisting of four bays.
The act did not provide the normal provisions for raising capital for the construction, as finance could only be obtained by leasing of the tolls. When completed, the commissioners leased the tolls to Charles Chaplin, who held ten shares and was also a commissioner, for an initial period of seven years. When the lease was due for renewal, no other takers were found, and Chaplin was granted a 99-year lease, despite the fact that the act did not authorise such an action. He collected the tolls but failed to maintain the navigation. When complaints were received, a new act of Parliament was obtained in 1828 (9 Geo. 4. c. xxx), to alter the tolls and legalise Chaplin's long lease. The lease was transferred to two railway companies in 1847, and reverted to the commissioners in 1876. The operation was a moderate success until the beginning of the twentieth century, when there was a rapid decline in income, and the canal formally closed in 1924.
Because the canal was also a land drainage channel, it was not subject to infilling, and is now a designated main river, managed by the Environment Agency that drains the surrounding land managed by the Lindsey Marsh Internal Drainage Board. It is as a feeder for Covenham Reservoir, from which treated water enters the public water supply. Water from Waithe Dike supplements the supply, effectively flowing upstream along the canal, and when required, additional water is pumped into the canal along a pipeline from the Great Eau.
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