Riparian Owner

If you own land adjoining, above or with a watercourse running through it, you have certain rights and responsibilities. In legal terms you are a ‘riparian owner’. If you rent the land, you should agree with the owner who will manage these rights and responsibilities.Main rivers are usually larger streams and rivers, but some of them are smaller watercourses of local significance. Taken from the EA's "Living on the edge"

Main rivers
In England, DEFRA decides which watercourses are the main rivers, and the Welsh Government does this in Wales.  Main rivers are marked on an official document called the main river map.  Environment Agency local offices have copies of these maps.  Main rivers can include any structure that controls or regulates the flow of water in, into or out of the channel.

Ordinary watercourse
An ordinary watercourse is every river, stream, ditch, drain, cut, dyke, sluice, passage and sewer (other than a public sewer), through which water flows, but which does not form part of a Main River. The local authority or Internal Drainage Board has powers on ordinary watercourses similar to the Environment Agency’s powers on main rivers.

Culvert
A covered channel or pipe designed to prevent the obstruction of a watercourse or drainage vector by an artificial construction. 

Flood defence
Some legislation still uses the terms ‘flood defence’ or ‘land drainage’. We now refer to these activities as 'flood risk management', but the EA may use the other terms for legal purposes.

Floodplain
A floodplain is an area of land over which river or sea water flows or is stored during a flood. Floodplains usually extend beyond the land immediately next to a watercourse.  There is often pressure to build on them, however, buildings or other artificial objects can obstruct floodplains, block the flow of water and make flooding worse.

Groundwater
Groundwater is all water which is below the surface of the ground or in the subsoil.

Surface water run-off
Surface water run-off is rainwater, and includes meltwater from snow. It is water on the surface of the ground, including standing water, which has not yet entered a watercourse, drainage system or public sewer.

All definitions from EA - Ref: Living on the Edge