River Ems (Chichester Harbour)

The River Ems is a much-sluiced, six miles (9.7 km) river that is located in the far west of the county of West Sussex, England.The last one and a half miles (2.4 km), of this river, delimits eastern Hampshire, before flowing into the sea at Chichester Harbour.

The river was so named, the "Ems", by a chronicler in the Tudor period.

Over the centuries various cartographers and chroniclers have suggested a variety of sources for the Ems.^[1] According to research by David J. Rudkin the River Ems has its source about one and a half miles (2 km) east of Stoughton.^[1]

The River Ems has a catchment area of over 60 square kilometres (6,000 ha), and its upper reaches drain the South Downs.^[2]Along the county-limits part, of its west bank, is the old town portion of Emsworth that contains mainly pre-1900-built buildings. The Ems flows south west through Walderton as a broad-catchment winterbourne.^[1] It runs past:

• the hamlet that includes well-preserved Lordington House
• Racton Monument which has nearby in Racton hamlet the church for Lordington
• A copse, Ractonpark Dell
• the village of Westbourne, has the westmost section of the Ems, in Sussex. Westbourne receives a year-round brook from the north and that descends under the railway at Emsworth (in Hampshire), becomes tidal, drains Brook Meadow to Peter and Slipper Mill Ponds from where it discharges into the sea. At lower tides it helps forms at the head of Emsworth Channel in the harbour; its last few metres enable access to Emworth Marina, the other former tidal mill pond.^[3][4]

There is little or no surface water in prolonged dry periods as the downstream springs have lowered the level of the water-table. However, when the underlying aquifers are full, the rain runs off and the stream system starts to function.^[5]

It is sometimes thought that the town of Emsworth derives its name from that of the River Ems, this is not correct as before the 16th Century the stream was originally called the Bourne.^[a] The river was renamed by the 16th century chronicler Raphael Holinshed. Many of the towns and villages that the River Ems runs through or past still have Bourne as a suffix. e.g.:Westbourne.^[7][8]

The Emille cometh first between Racton and Stansted, then down to Emilswort or Emmesworth, and so into the Ocean. Separating Sussex from Hampshire almost from the very head.

— Holinshed 1577, p. 21

50°54′13″N 0°51′08″W / 50.90363°N 0.85227°W / 50.90363; -0.85227