Throughout the summer and early autumn, a combination of warm weather, sunshine and extra nitrates from agricultural run-off create perfect growing conditions for duckweed, water fern, common reeds and Canadian waterweed. These fast-growing plants are spread by passing boats, canoeists, paddle boarders, anglers’ nets and walkers’ muddy boots and, left undisturbed, can form a thick green carpet on the water. This can then cause problems for boat engines, and its solid appearance makes it a potential danger for children and animals. Hotspots for the invasive weeds are low flow areas around the Lancaster Canal, Garstang, Cabus Nook, north Preston, Radcliffe Wharf and Woodplumpton.
The Canal & River Trust says it has stepped up its response on the Lancaster Canal with a massive vegetation clearance programme, including the use of a Truxor amphibious tractor, which this year has scooped up hundreds of tonnes of problematic and invasive weeds from the waterway.
The water supply for the Lancaster Canal feeds through via the unnavigable Northern Reaches link from Killington Reservoir, near Kendal, and keeping that channel flowing freely is also a constant challenge.
Angela Parkinson Green, local area operations manager for the Canal & River Trust, says: “Since 1968, the canal has only been navigable from Tewitfield southwards after it was severed in three places by the construction of the M6 motorway. This gives us unique challenges on the Lancaster – including the loss of nearly two thirds of the water supply between Killington and Tewitfield. As well as weed and silt removal, every day our staff have to clear out the three M6 culverts which carry the canal water supply under the motorway.