Rising at Watersend, near Temple Ewell, the Dour is a chalk river that is regarded by the Environment Agency as the best Brown Trout habitat in Kent. Centuries of industrialisation along its eight kilometre course have taken their toll on the river, and now nature needs a helping hand to preserve the Dour.
It is due to the Dour that Dover owes its very existence; the valley that it cut through the chalk cliffs providing a grateful haven to the first settlers, and by the Roman period the wide estuary of the river made an ideal harbour.
The industrial use of the Dour can be traced back to AD 762, when the first written records of a corn mill at Buckland were made, the first of any mill in Britain. Over the years, the use of the river as a source of industrial power served thirteen watermills - eight being corn mills, the others manufacturing paper, as well as iron foundries, saw mills and a tannery.
This industrialisation led to the Dour being dredged, widened, cleared of plant life and diverted, giving the river channel along its length an unnatural, straightened form with artificial man made banks.
Where a river flows in a widened channel, as the Dour does in many places, silt builds up as the flow of water is too slow to keep the particles and dead vegetation suspended, so they deposit on the river bed. This will gradually build up, covering the gravel on the river bottom which is needed by the fish to spawn in.
Siltation also means that insects such as Mayflies, Damselflies and Caddis Flies upon which the trout feed cannot survive, as they too rely on the cracks in between the gravels and stones to live.
Rotting vegetation also reduces the quality of the water, producing toxic gases that rob the oxygen from the water. This then leaves a habitat that is only suitable for the most pollutant tolerant species like Blood Worms and Chironomids.
The biodiversity of the river is also hampered by the introduction of non-native plant and animal species such as Himalayan Balsam and North American Signal Crayfish. Himalayan Balsam grows aggressively, and can very soon overwhelm the river bank, blocking sunlight and preventing native species from taking hold, whilst the introduction of the North American Crayfish also brought crayfish plague to our river systems. Our native species, the White Clawed Crayfish, found itself under attack from both a disease it had no immunity to, and from a larger, more aggressive predator.
The River Dour is now being managed pro-actively by the Environment Agency, which recognises that chalk streams are a priority habitat for protection and conservation. I joined Tom Reid, Biodiversity Technical Specialist and his colleagues in torrential rain and thunderstorms at Temple Ewell as they were in the process of reintroducing plants such as Water Mint, Marsh Marigolds and Water Figwort to the Dour.
Temple Ewell Parish Council has worked closely with the Agency to restore the river; gravels have been introduced and silt has been dug from the bed, then shaped to create meanders and bends that mimic the natural course of the river.
Local residents are in full support, Mr Hailwood's property faces on to the river and he considers the work to be, 'absolutely fantastic, in the last 25 years I have seen the river go from bland stream, to disappearing completely, to the wonderful sight that we have today.'
The urban nature of the Dour as it flows through Dover presents many challenges, and the Environment Agency will be working with the River Dour Steering Group to maintain and protect the river.The Group meets twice a year and provides a forum for those interested in the Dour. Members include the Environment Agency, the White Cliffs Countryside Project (responsible for litter clearance working parties), Dover District and Dover Town Councils, River and Temple Ewell Parish Councils, voluntary groups such as the Dover Society and River Conservation Society, Dover Harbour Board and Veolia Water.
The Group receives presentations of the work, plans and ideas of the members with the intention that local people are made aware of what is, and what will happen, to maintain and improve the Dour, and at the same time local concerns can be raised. Currently the main concern is the silting up of the old mill ponds and the risk they pose of flooding.
Those who come to the meetings are only too aware of the special nature of Dour and of how much of an asset it is for the town, albeit one that has only achieved a fraction of its potential.
Copyright Paul Isles/Dover Life Magazine