Common law imposes a duty on the occupier of land adjoining highways to maintain roadside ditches which provide natural drainage for both the land and the highway.

The highways authority has a prescriptive right to drain the highway to adjoining ditches.

In the majority of cases the responsibility for ditch maintenance lies with the adjacent landowner.

The highways authority is responsible for stormwater run-off from the highways by regular maintenance and cleaning of gullies (drains) and grips (drainage channels in verge).