It was built in 1993, and the suspension footbridge was moved to the north of the town at the same time. Lower river After passing Kendal sewage treatment works, on the west bank, the course follows a large meander to the north. The land it surrounds is a scheduled monument, as it was the location of Watercrook Roman fort and civil settlement. Archaeological excavation has revealed that the site was occupied from 90 CE to 369 CE, and the remains are fairly well preserved. Above ground, the site is marked by a number of low earthworks. As the river resumes its southward course, there is a large weir which supplied a snuff mill. The mill is Grade II listed and the snuff grinding equipment is still in situ. To the west of Natland, the river passes through a small limestone gorge, which is crossed by the two-arched Hawes bridge, probably dating from the 18th century, and made of limestone rubble with cut limestone copings. Below the bridge, woodland on the west bank contains the remains of Sedgwick gunpowder works, fed by a long leat from a dam in the river. After passing under Force Bridge, Sedgwick, on the east bank of the river are the remains of Basingill gunpowder works, which is a scheduled monument. The river turns to the south-west, and is spanned by a much larger bridge carrying the A590 dual carriageway, before it enters Levens Park. As it leaves the park, the A6 road crosses the river on Levens Bridge, dating from the 17th century, although it has been widened subsequently and was rebuilt and repaired during the 18th and 19th centuries. The river from Kendal to Sedgwick is popular with kayakers, as it contains a number of rapids and drops. It is not a river for beginners, offering whitewater rated at grade 3 with some grade 4 on the International Scale of River Difficulty, and it becomes more challenging as flow rates increase. The white water section ends at Force Falls, just above the A590 bridge at Sedgwick. The river becomes tidal shortly afterward, as it widens into an estuary. It is joined by the River Gilpin, flowing southward, which forms the boundary of the Lake District National Park in its lower reaches, and the River Bela, flowing westward. The national park boundary then runs along the middle of the river channel. At Arnside, the final