Roadside ditches are normally the responsibility of the adjacent landowner even though the highway may drain into them and there is a common law duty on the adjacent landowner to maintain them.
Fel arfer y tirfeddiannwr cyfagos sydd â chyfrifoldeb dros ffosydd wrth ymyl y ffordd a dylid eu harchwilio a'u cynnal yn rheolaidd gan y tirfeddiannwr.