The much-sluiced river Ems runs for six miles (9.7 km) along the border of West Sussex before flowing into the large, coastal Chichester Harbour.
According to research by David J Rudkin the River Ems has its source about one and a half miles (2.4 km) east of Stoughton. The Ems is not just a river but a vital resource for local people. Walkers find beauty and relaxation along its banks, children experience nature around it and dogs use it to splash around in.
Did you know?
It was thought that Emsworth derives its name from the River Ems but this is not true, as the stream was originally called ‘The Bourne’. The river was renamed in the 16th century by chronicler Raphael Holinshed. The river’s original name is the reason many local towns and villages that the River Ems runs through or past still have ‘bourne’ as a suffix in their names.
The Ems flows through:
- Lordington hamlet that includes the well-preserved Lordington House
- Racton Monument with the church for Lordington in Racton hamlet
- Westbourne village with the westmost section of the Ems in West Sussex
- Emsworth with the West Sussex and Hampshire border along its West bank
Westbourne receives a year-round brook from the north that descends under the railway at Emsworth in Hampshire. After this point the Ems is tidal, draining Brook Meadow to Peter Pond and Slipper Mill Ponds and then discharges via Emsworth Channel and Chichester Harbour into the Solent. At lower tides the Ems helps form the head of Emsworth Channel in Chichester harbour and its last few metres enable access to Emsworth Marina, a former tidal mill pond.
The Ems is one of only 160 English chalk streams that derive most of their flow from chalk fed groundwater and flow over a chalk geology. Imagine the Bourne landscape as a layered cake with old chalk rock sandwiched between younger rocks like sands and clays above and older rocks like greensands below. If you tilt the cake and then run a cake slice across the raised edge this is a very simple version of what the landscape of southern England looks like. A band of chalk is exposed at the surface with older rocks to the north and west at the foot of the steep scarp-face of the chalk, and younger rocks beyond the longer more gently inclined slope-face of the chalk.
Did you know?
Chalk geology is rare worldwide and England has most of the chalk rivers in Europe, with only 35 chalk rivers 20 to 90 km (12 – 56 miles) long in the UK. Chalk rivers are wide but streams are defined as being under 5 km from their spring source and no greater than 5m (16 feet) wide. Many Sussex chalk streams have their source high in the South Downs, making the gradient of the streams much steeper. This sets Sussex chalk streams apart from other streams in the UK and makes them of global importance.
The Ems flows south west through Walderton as a broad-catchment ‘winterbourne’, meaning a river that flows during winter when rains area greatest but that can dry up completely in late spring and summer. Classic chalk stream characteristics are having very clear water and regular flows but other types have a fast response to localised rainfall and have a distinctly seasonal flow, usually highest in spring after the winter rain recharge and falling away through summer and early autumn to a slower or even zero flow.
Did you know?
Even though the river has a flow gauge which confirms a flow variation of 1,000 times in the year, there is debate about whether the Ems is a classic ‘winterbourne’ or whether it is suffering from over extraction by water companies seeking fresh supplies during increasingly dry summers. Whatever your views the Ems is a crucial wildlife habitat, and a lack of water at critical times of the year means fish and other wildlife can die and the health of the river system can be permanently damaged.
In 1999 the Environment Agency recognised the importance of chalk streams for their unique features, ecology and associated wildlife and indexed and mapped 160 chalk-streams. A Biodiversity Action Group report, The State of England’s Chalk Rivers, has been updated several times since to help protect them. New guidance now provides better coverage of small chalk streams in headwater areas, including the seasonally flowing ‘winterbournes’ which are important for biodiversity and certainly deserve better environmental protection.
- Read about the threat to local chalk streams – click here
- Read more about English chalk streams – click here
- See the full list of 160 English chalk streams – click here
- Clear chalk streams and Nutbourne watercress – click here
- Become a Friend of the EMS (FOTE) – click here
- Detail on chalk streams at Wikipedia – click here