Complex sentence: The middle section crosses Baggy Moor, where major improvements were made in 1777 to drain the moor, and a section of the river bed was lowered in the 1980s, to continue the process.
Split into simpler sentences: The middle section of the river crosses Baggy Moor, where major improvements were made in 1777 to drain the moor. A section of the river bed was lowered in the 1980s, to continue the process.