Rivers on an OS map

Ordnance Survey exercise

OS map extract featuring the River CreeOrdnance Survey River Cree © Crown copyright and database rights 2013 Ordnance Survey 100039117

As well as explaining the formation of river features, you also need to be able to describe the physical features of a river and its valley using an Ordnance Survey map.

The map extract shows the River Cree in south-west Scotland. We will take a journey along the river describing the main physical features - remember that this means natural features not man-made ones!

In the OS map extract featuring the River Cree:

  • At 400670 the River Cree joins the map. It is flowing in a south-easterly direction. We know this because the river gets wider as it nears the estuary/mouth of the river.
  • At 410664 a tributary joins the river at a confluence. The river now flows south around an island. The valley is relatively narrow (you can see contour lines close to the river on both sides).
  • At 416647 the river becomes tidal. We know this because the edge of the river changes from blue to black.
  • At 417642 there is a meander. The river valley now broadens out to more than two kilometres wide, covering two grid squares.
  • At 422641 the river begins a series of large meanders. There is an embankment on the south bank of the river - this could be a natural levee.
  • The neck of the meander at 425637 could eventually be broken through by the river to form an oxbow lake.
  • At 429640 the river starts to widen and mud/silt is showing in its bed.
  • Many tributaries now join the river - 434623 (the Brushy Burn) 441627 (The Lane) 453624 (Palnure Burn).
  • The river is now flowing in a very flat, wide and low-lying valley (7m and 5m spot heights). This has resulted in marsh land at 452612, 456606 and 465590.
  • The river enters its estuary at 467580.