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The River Medway

The River Medway

NRA Southern 36

THE RIVER

National Rivers Authority Nat. Southern Region

Infon Guardians of Head C ce the Water Environment

Class N o ....

4,.. RWjl widens between Rochester HYDROLOGY THE and until the flows into the . The Wealden rivers respond rapidly to rainfall and extremes o f RIVER The total length o f the main flow may vary five-hundredfold between summer and winter. Medway from source to the There are six flow gauging stations on the main river, three on the Estuary at Sheerness is 110km River Eden and three on the . The Eridge Stream, the MEDWAY (70 miles). The river has a Bartley Mill Stream and the Rivers Bourne, Bewl and Beult are also catchment area o f 1400 sq km gauged. above the tidal limit and 402 There are three water supply reservoirs in the Medway catchment, COURSE AND sq km b elow the tidal limit. Bough Beech, W eir Wood and . GEOLOGY HISTORY RESERVOIR VOLUME DESIGN YIELD WATER AREA LOCATION (Ml) (Ml/d) (ha) The River Medway rises in the

Ashdown Forest as a spring The name o f the river may Bough Beech 8,630 22.7 113 Tributary of issuing from the Tunbridge derive from a Celtic word, (East River Eden Wells Sands just above Turners Medu meaning mead, presum­ Water Company) Hill. The sands and clays of the ably signifying a river with High dictate the charac­ “sweet” water. The Romans Weir Wood 5,623 14.1 113 Upper Medway (Southern Water ter o f the river, w hich w ith its called the river Fluminus Services Ltd.) many deeply incised tributaries, Meduwaeias and the Saxons contrasts sharply with the chalk knew it as the Medwaeg. Bewl Water 31,367 76 312 Tributary of streams found in other parts of Historically the importance (Southern Water River Teise the region. The Wealden clays o f the area lay in its relatively Services Ltd.) are impermeable to rainfall and rich and accessible iron water must find its way across deposits. These were exploited the surface of the steeply slop­ on a small scale in the Iron Age Bewl Water near is the largest reservoir in the ing land, creating a multitude (the grey clay con­ Southern Region and is filled partly by inflow from its natural o f small rushing streams. tains iron nodules or “sows”, catchment and partly by water pumped from the River Teise at These meet to form a typical some with an iron content as . Pumping normally takes place in autumn and winter to Wealden vale as the Medway high as 55% ). In Roman times fill the reservoir for use during the summer. The amount o f water flows north-eastwards towards the ore was heated by charcoal taken from the River Teise is regulated by the National Rivers . There, the river is in a clay-walled mound through Authority by a licensing system which ensures that flow does not joined by the River Eden. As it which air was forced by bel­ fall below 23 Ml/d (5 mgd). Releases o f water from the reservoir flows across the Vale of lows. The and are used to support Southern Water’s abstraction on the River the gradient is less, though the the High Weald supplied Medway in when natural flow in the river is insufficient. river still collects tributaries abundant timber for fuel. After Once river flows are below 352 Ml/d (771/2 mgd), no more water which rise in other parts of the several centuries of decline the may be taken in Maidstone than is being released from Bewl Water. High Weald. These include the industry was revived in Tudor The scheme benefits the River Teise and the River Medway bet­ Rivers Bourne, Teise and Beult. times when the more sophisti­ ween the reservoir and the abstraction point. Mid Kent Water T h e River Teise has m ixed cated blast furnaces introduced Company also uses Bewl Water to supply its treatment works origins; the Upper Teise once by the French were pioneered on site. flowed eastwards to the Rother on the headstreams of the Whilst the largest single abstraction on the river is Southern but was captured by the Lower Medway. W ater’s intake at Maidstone, there are numerous small abstractions Teise when it cut away the soft The process produced cast for agriculture and industry licensed by the NRA. Spray irrigation clay ridge dividing the two iron which was forged into is the major agricultural use particularly on the River Teise and the streams. The which wrought iron. The steep Weal­ River Beult. rises in the Hythe sandstone den streams proved ideal for Average yearly rainfall in the catchment ranges from 667 mm in ridge is the longest tributary of impounding as “furnace” or the lower Medway to 756 mm in the upper catchment. the river. “hammer” ponds to provide a T h e M edw ay cuts its way head o f water to drive the twin through the Ridge waterwheels characteristic of beyond and collects Tudor forges. These drove two more tributaries, the Loose furnace bellows and trip Stream and the River I,en before hammers to forge the iron. reaching the County Town of Another important product Maidstone. The of the Medway Valley was for part of its length flows . This was underground. The is quarried by the Romans in the larger and longer, but flows Maidstone area and transported m ore slow ly and has its source to to build the City near the village o f Ixrnham. walls. The continued L’nlike the tributaries arising in the process, ferrying ragstone the High Weald the Loose and from the to build Len have more reliable springs the . Kentish which sustain their flow through ragstone is still used by the the summer months. National Rivers Authority to Allington Lock forms the build tidal defences. Its w ork­ tidal limit o f the M edway in men continue the traditional Maidstone from whence the skills of shaping the rocks to river flows North, cutting interlock into a durable defence through the chalk. The estuary w ithout the need for mortar. SOUTH EAST TOURIST BOARD

Warden Pi

arden

-■ / / s a in * pt.'f»etAnt> Y* Q ~ > ^ »G«lCUlTU»«il iHOWO*OUM' f l t U j L f ^ j | H ighbro^k "*l Despite low’ dilutions in bel and is an important spawn­ and rain gauges in the catch­ WATER QUALITY summer, the receiving water­ ing ground. Grayling have ment is telemetered to a con­ The National Rivers Authority courses are maintained in Class been stocked to the upper trol room, so that flow through sets objectives for river quality 2. The River Medway itself reaches over recent years and the gates can be regulated. to protect its natural stocks of achieves Class 1A and IB for all some also find their way down Between Leigh and the tidal fish and the uses to which it but an 11.8 km stretch below the River Teise into the River limit at Allington there are ten is put. To achieve these the confluence with the River Medway. navigational locks, and accom ­ objectives, the Authority sets Grom which achieves Class 2. Eels are not so prolific in the panying flood control sluices. limits on all permitted dis­ Historically, the naval base Medway catchment as on the Nine have by-pass channels charges to the river, restricting at Chatham gave great econ o­ Kentish Stour and the River with automatic high capacity their strength and quantity. mic impetus to the lower Rother. In w et years the cx’ca- sluices which maintain a con­ These are known as consent reaches o f the river and its sional sea trout or salmon is stant upstream level and take conditions. estuary. Urban and industrial reported but existing water surplus flows. Six of these have Historically urban develop­ development have been signifi­ conditions in the estuary pre­ radial gates finely balanced by ment and industrialisation cant factors affecting the water vent a self sustaining population a counterweight on the end of have taxed the river’s ability to quality. The principal dis­ from being re-established at an arm. A device with a float­ absorb waste. However, the charges comprise effluents present. like action is attached to the National Rivers Authority and from the paper and chemical arm causing it to tip the — its predecessors have been industries, cooling waters from H G ^ u d g e o n * balance when water levels rise. able to bring about improve­ power stations and sewage Bullhead The gate then opens until ments by imposing increasingly effluents from several large water levels fall and the “float” more stringent consent treatment plants. Apart from resumes its original position. conditions. the cooling waters, all effluents Three other sluices have verti­ are treated before discharge to cally operated gates which are QUALITY LENGTH the estuary. CLASS OF RIVER electrically powered. The (km) Motney Hill and tenth lock has hand-operated Sewage Treatment Works are rack and pinion, tumbler 1A Water of high quality suitable 23.7 the two largest in Southern Re­ sluices but will be modernised for potable supply abstraction, high class game and coarse fisheries gion with flows o f 42,000 Ml/d in 1991. and 25,900 Ml/d respectively. The NRA sluice and lock IB Water of high quality suitable 312.8 for high class game and Under normal flow condi­ keepers trim levels and operate coarse fisheries tions, effluents are diluted and Allington Lock and the lifting

2 Water supporting good coarse 59.8 dispersed in the tidal waters of bridge at Yalding. A hydraulic fisheries with moderate amenity the estuary. However, at times dredger is operated by the Au­ value of low flow and high tempera­ r * thority all year round to clear 3 Water from which fish may be 0.2 tures the upper reaches can blockages and shoals. absent or only rarely present and become substantially devoid of FLOOD DEFENCE which is suitable for low grade oxygen. This is aggravated be­ industrial abstractions The impermeable clay and the cause the major polluting loads MEDWAY PROJECT 4 Grossly polluted None large areas of urban develop­ are imposed towards the head ment give the river its flashy In March 1988 the Medw’ay of the estuary. To meet the Low' summer flows and high character making the NRA’s River Project was established challenge, the NRA plans to re­ temperatures make Wealden Flood Defence role of para­ to improve the leisure and view consent conditions on rivers less easy to protect than mount importance. tourism potential of the discharges to improve water the chalk streams in other Historically the Medway Val­ Navigation. quality in the estuary. parts o f the Region. The risk of ley and Eden Valley suffered It is funded by a partnership pollution from agricultural flooding of both agricultural of the NRA. Countryside activity is a significant factor, FISHERIES land and property. In Septem­ Commission, Kent County especially in the High Weald The iron rich streams of the ber 1968 the worst flood in Council, Maidstone Borough where there are many small Weald support resident popu­ living memory occurred caus­ Council and & dairy farms. The steeply slop­ lations of small but highly ing massive damage both in the Mailing Borough Council. ing land and the impermeable coloured brown trout. The town of Tonbridge and in the The aims of the project are clay aggravate the effects of River Teise is managed as a downstream areas. to: game fishery down to Marden In order to alleviate flood­ slurry and silage pollutions, • Re-establish and maintain a w'hereas the lower stretches of ing, a flood storage area was particularly during periods of continuous towpath bet­ both the Teise and Beult are created above Tonbridge at heavy rainfall. ween Allington and Leigh. Between Tonbridge and managed as coarse fisheries Leigh and is now operated by Maidstone the river flows with chub, dace, roach and the NRA. This is the largest on- • Develop circular walks link­ through the ‘Garden o f Eng- pike. In the middle and lower river flood storage area in the ing points of special in­ land’ where fruit growing reaches of streams where the UK. In times of heavy rainfall terest. water is deeper, there are three gates in an earthen predominates, sometimes giv­ • Enhance landscape and w ild­ bream and tench. Minnows, embankment across the river ing rise to pollution from agri­ life. cultural chemicals. gudgeon, stone loaches, bull­ regulate the amount o f fkx>d Population growth in Ton­ heads, brook lampreys and water passing downstream to • Manage the river for the bridge, Tunbridge Wells and perch are also found in riffles. Tonbridge. Some of the run-off benefit of recreation and oth er com m uter areas has The main river has consider­ is held back, forming a tempor­ wildlife. resulted in greater quantities able angling interests over its ary lake whenever the flows • Encourage local communi­ of treated domestic effluent entire length and attracts large exceed the channel capacities ties and landowners to take b ein g discharged to the river In numbers of fishermen. The up­ through the town. The “lake" a positive role in caring for particular there are relatively per reaches support chub, can be drained at a controlled the Medway. large sewage treatment works roach and pike along with rate once flood flows have on the River Fden, the River several other species. The abated. • Encourage river users to en­ Grom, the Somerhill Stream stretch below Ashurst Weir has Information from flow gaug­ hance the Medway and its and the Botany Stream. a breeding population of bar­ ing stations, level recorders boating facilities. HISTORY OF THE Survey o f Rivers and Coast in the South-East Region - REFERENCES The Rivers o f Kent. Mature Conservancy Council, te a Ids, 1531 ‘Commissioners of Sewers'were Perm R (1981), Portrait of the Ril'er Medway. Robert Hale Ltd Church Street. W'ye, Ashford, Kent, TN25 5HW established to improve lond droinoge and Coodsall, R.H. (1970), The Medway and its tributaries - The Medway Elood Relief Scheme, National Rivers Authority, prevent flooding. The Medway Commissioners EP Publishing Ltd. Southern Region. also proposed to dear the nverfor navigation, 'sofhatHs natural course is unobstructed and her Majesty 's subjects con travel along it in Hythe Beds and • Chalk boots as o highway with carts.' Boundary of Atherfield Clay 1624 Further moves were mode to moke the catchment area Upper Greensond rrver navigable to transport oak trees from the □Wealden Clay ond Goult Weald to Chatham for shtp building. The weirs Flood storage area and a low bndge at Netllesteod seem to hove Tunbridge Wells Sand, stopped this scheme. Flood plain protected Wadhurst C lay and 1664 The first specific Navigation A d gave by the scheme Ashdown Beds powers for certain ‘undertakers'to 'erect, □ build, set-up and male'locks, weirs, turnpikes, Sewage Treatment Works pens of water, whorfs and cranes to load and ® unlood iron, ordnance bolls, timber ond other materials. Flow gauging stations

1739 A second Act was passed to make the Abstraction for Public Supply river navigable to . Locks were built <*> between Moidstone and Tonbndge by 1746. The Xom pony o f the Propnetors o f the Navigation o f the River Medw ay 'transported materials down river for the Navy and com, hops, coal ond lime upstreom. 1828 James Christie was engaged as canal engineer to plon on extension from Tonbridge to Penshurst. He asked for special rates for his own barges and purchased Tonbndge Town MiHs to control the water nghts. His draining of the Town Pen in 1829 which stranded al borges at the whorfs resulted in legal ond physical battles which bankrupted him.

1842 The railway brought competition to river transport. In 1892 a new navigation company was formed but fell into receivership by 1910. 1911 The prospect of the river becoming derelict led to the creation of the Medway Conservoncy Boord The Navigation between Moidstone ond Tonbridge wos re-opened in 1915. 1934 Powers were token over by the River Medway Catchment Boord under the 1930 Lond Drainoge Act. Successor bodies were the Kent River Board ond the Kent River Authority. 1974 Responsibility for the Navigation transferred to the Southern Water Authority. Commercial traffic hod ceased, but the water Sections showing the general relations of the rocks along the lines X—X', drawn on the map remained populor for pleosure boots. 1989 The Water Act invested responsibility Ragstone Vale of High Weald Ridge Homesdale for the Navigation in the National Rivers Authority. A restoration and maintenance programme ensures that itwi continue to be enjoyed by boat owners, anglers, ramblers and the general public

Vertical Scale about ten times the Horizontal

ENVIRONMENT AGENCY

NRA

N ational Rivers Authority

Southern Region

Headquarters Guildboume House Chatsworth Road Worthing West BN 11 1LD (0 9 0 3 )8 2 0 6 9 2 July 1991

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