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The River Test

The River Test

N A A S o o 4V\z /v \ ^ - 5

THE

E n v ir o n m e n t A g e n c y

NATIONAL LIBRARY & INFORMATION SERVICE

SOUTHERN REGION

Guildbourne House, Chatsworth Road, Worthing, West Sussex BN 11 1LD NRA

ational Rivers Authority

Southern R egion

Guardians of

the Water Environment ENVIRONMENT AGENCY

054505 and grist milling and the divisions, these being the flows do not have the support THE generation o f electricity, though Upper, Middle and Lower Chalk. of resilient springs. none o f the traditional mills The first outcrops over much For these reasons, chalk have survived in working of the catchment but there are streams characteristically have RIVER condition. some exposures of Lower few tributaries compared with There are still extensive Chalk, particularly in the North rivers draining impermeable TEST remains o f the water meadow West above . areas. The drainage densities of system, which was used to fkxxl From southwards the Test and Itchen (km of fields with the relatively warm there are younger rocks of stream/sq. km of land area) are river water in the early months Tertiary origin. These are a around 0.12 compared with of the year to promote an early mixture of silts, clays and sands values of up to 0.47 for the COURSE AND growth o f grass. The tempera­ which are much more im­ clay-vale rivers of Sussex and ture o f chalk streams is always permeable than the Chalk. Kent. HISTORY higher than soil temperatures There is an important inlier of The actual line of the River The River Test is probably the in the winter months due to Tertiary rocks into the Chalk Test and its tributaries falls most famous in the large groundwater to the West of over approximately on a right angle southern , draining a component. “Carriers” along which the flows. grid pattern, reflecting the way surface catchment of some the sides o f valleys were used The landscape of the area the chalk was flexed by geo­ 1,260 sq. km. It rises in the to flood the meadows and the was shaped in the last Ice Age. logical movement. Upper Chalk near the village of water was returned to the river The precise origin of the dry The NRA measures flows at a Ashe, East of Overton and soon via low level “drains”. Many of valleys in the rolling Chalk number of points using specially collects a handful o f small these larger channels still exist Downs is still uncertain, but designed weirs. There are spring-fed tributaries on its but the system became derelict they were probably formed by gauging stations on the River passage southwards; the Bourne with changes in agricultural stream erosion when the Anton at Fullerton, on the Rivulet, the Dever, the Anton, practice and because it was ground was frozen, causing Wallop Brook at Broughton the Wallop Brook and the labour intensive. rainfall to run over the surface and on the River Blackwater at Sombourne Stream. From the Between Timsbury and rather than soaking into the Ower. upper reaches the river widens a stretch of the chalk. The main long term flow considerably and meanders Andover - Romsey - Redbridge Apart from evaporation, records (since 1957) is from through a wide floodplain, still exists. This canal almost all of the 824 mm of where average flanked by water meadows. was authorised under a private annual rainfall that falls on the flow is 11.8 mVsec (224 mgd). Within its broad valley it fre­ Act o f 1789 and was 22 miles Chalk catchment soaks into its More recently an electro­ quently splits to form a network long with a fall of 176 feet. In deeper layers which are fully magnetic gauging station has o f braided channels. From Mot- the early part o f the 19th saturated with water. The been installed at Testwood. tisfont southwards, the Test Century' an attempt was made water moves through the flows over less permeable soils to build a canal from Chalk under the influence of and rocks and is joined by the to join the at gravity until it issues from River Dun, Tadburn Lake, Mottisfont but it was never springs in the valley bottoms, Greenhill Lear and the Black- successful. feeding the river system with WATER water. The wide fkxxlplain Peat has been dug for fuel in high quality water. continues to the tidal marshes a number of places and there The National Rivers Authority RESOURCES between Testwood and Red­ are “peat holes” on the North collects information about the The development of South bridge where the river outfalls side o f the Houghton-Horse- groundwater and its fluctu­ , based historically to Water. bridge Road and the large ations using a network of over on rail and sea links, but more The Hampshire Rivers were pond near has the 440 wells and boreholes in the recently on the improved road once tributaries o f the ancient same origin. Test catchment. network, has generated a con­ Solent River which flowed east­ Generally rain takes several tinuing demand for water for wards from the River Frome to months to find its way through domestic and industrial use. join the sea somewhere near the Chalk to the springs, so the The Water Act 1989 gave Littlehampton in times when winter rainfall which swells the NRA the duty to ensure the Isle o f Wight was part o f AND the underground reserves gives that water resources are the mainland. This trunk river peak river flows in late spring conserved and managed system was dismembered HYDROLOGY and through the summer. With properly. Consequently the during the Pleistocene Period The underlying rocks of the slight variation in flow between Authority will play an im­ when the sea made inroads Test catchment form part of seasons, the river has created portant role in balancing the into the catchment to the East the northern flank of the very little freeboard to the top needs of the environment with and West o f the Isle of Wight. , a geological of its banks. those of the water user in the More recently, the activities feature in which the rocks Although the range of flows face of future development. o f man have shaped the River slope gently or dip from the is slightly higher than the The prolific chalk streams Test. The braided channel North to the South. The oldest neighbouring River Itchen, provide much of the water system is a legacy o f the historic rock is the Cretaceous Chalk maximum flow in any year is used in Hampshire, particularly uses o f the river for milling for which outcrops over the whole typically only 4-5 times the from their lower reaches. land irrigation of “water o f the valley to the North of minimum. This contrasts Some water is also pumped meadows” and for navigation. Mottisfont. This is a porous sharply with the Wealden from boreholes penetrating The river once provided fine grained limestone which rivers where surface run-off in the chalk aquifer. power for wool processing, is generally very permeable. winter can boost flows several The NRA is now the licens­ paper making, tanning, flour There are three main sub­ hundred times, and summer ing Authority for all abstrac 11. lur;

% tions and considers the environmental aspects of a , FINja^=dOWN rsto k e \\ 7\J proposed abstraction and its ieCe PK. m a o v e i\ rhittihurch 'e s to n effect on other lawful water DoW li 03400 IfiaJrick 'HITCHTCfcflCH users. In order to protect over­ SILK M „ flows, restrictions are attached to licences to ensure that water is only taken from speci­ la ris h fied locations and at times ? a , when it can be spared. i arewi Forest An important consideration : h e d / - ^ ^ u is the extent to which the ILLAC water is returned to the river Xgrwell ton and the point of its return. >tacey Water taken out of the catch­ ment or “consumptive use” is a teas loss to the river system. Some lilbortfi.n ille rto r iB3420 uses such as spray irrigation lTElLITSj:RACKIN< Over (atercr* STtf- are entirely consumptive lA/ o I I n r i f fid d le FISH .e c k fo rd because of evaporation or Chapmansford Farm, & HATCHEF export out of the catchment. Conversely almost all water­ ton cress growing, gravel washing, Lof and fish farming abstractors jrn e return all the water to the tY RING fockbridj same location, so overall effects Fort) fil Coaching Tq on flow are small. On average, TVIidrfle h o u g w jo i; 80% of water abstracted for (slov jgnton l o d g e domestic supply is returned to W inter£lov the river after proper treat­ ment. On the River Test con­ Pitton Comnjio'f & sumptive use represents only W ast King's'; 2% o f total average flow. Tythiw le^ So m borne' The major abstraction for H O R i public water supply at Test­ MONUMfNTl wood is located close to the tidal limit so that water is taken just before it is lost to the estuary. The licence ensures fliv e r/ '< MIZ- MA'iE that sufficient flows are pre­ M ^RDONI c) B^wry 4 served for the needs of migra­ C om p tc tory fish. i h a w f o r d , Abstraction licensing was introduced by the Water Resources Act 1963 which was tt( the first statute to control the amounts of water taken from gan s rivers. At that time established lie NEV abstractors were given “Licen­ ces of Right” to continue taking B utserj lo w / A27 4 * * water at the existing rate and LORfNCJL-— 'z— I ^ n 1 - at the same location. The NRA RAVl \| // pflC»DLAP has found that local abstraction Sll V H i on the Wallop Brook and the % ^ | S ( ^ RVjC Bourne Rivulet causes low % 7JJ /J Uj * Lec _ o b L 'S , 4 flows. Remedial action is being fmr 4 )WtTr?ita owrttTatn^ _z Y § * - f t o > investigated by the NRA for both tributaries. r Fish farms and watercress 1s t Ihatn Jewbrit farms were exempt from ab­ NRA straction licensing until the II Brook v Water Act 1989. Licences of ( / National Rivers Authority EffTwutq30RE Entitlement for established L P \A/1 n W£U «. /-*ih- r-\ abstractors enabled them to Southern Region Cartography prepared and published by ESTATE PUBLICATIONS continue taking water in the with the editorial assistance of the REV %U$. same amounts and at the same SOUTHERN TOURIST BOARD rttrgq ^ )) / / t Based upon the maps with the locations. sanction of the controller of HM Stationery Office. P ic n ic - S jr g ia X s t^ e e ts ^ h y d r o t h j i l ^ Estate Publications j Crown copyright reserved ridge. L ° S E R V IC E Jsr«r»S5r-‘c^'\\ ^COyVES \V I r *,32' ^ T nt iP T So C ib d e r™ 1* F u n tle \ Boarhunt^1 1 P ^ = = ^ \^4T<7=v, O vi T \ X rc \ tiO 'y T "

consents, particularly with carried out on tidal waters and WATER regard to the amounts o f silt along all reaches of the river. released and to the use of other As part o f a fisheries manage­ QUALITY pollutants. ment programme, hatchery The natural high quality o f the The catchment is predomi­ reared salmon are restocked to chalk streams stems from their nantly rural with a population the river. Fish passes have been springwater which has had a spread across small towns and installed at weirs and river long residence time in the villages in the North, or concen­ structures to assist the passage ground and has been filtered trated in the conurbations of migratory fish to their through the chalk. The water is alongside . spawning grounds. Such passes clear, hard and alkaline and its There are two substantial dis­ are operating successfully at temperature varies little be­ charges of treated sewage Testwood, . Drawing­ tween seasons. effluent made directly to the room Pool (on the Little River These features give chalk river; at Andover and Romsey Test) and at Abbey Mill, Test streams a good capacity to where the sewage treatment Mill and Saddler’s Mill in absorb and assimilate effluents. works have consented dry Romsey. The NRA sets objectives for weather flows o f 16,000 m Vd Electronic fish counters Grayling river quality to protect natural and 6,410 mVd respectively. record the number o f salmon stocks o f fish and the uses to Sewage treatment works at running the river, enabling prepare for the spawning which the river is put. The , Kings Sombourne their movements to be related season. This practice has slipped highest objective in the classi­ and Stockbridge all have flows to flow, turbidity and other into abeyance in recent years fication is Class 1A (water o f below 500 mVd. In addition environmental parameters. because of manpower and re­ high quality suitable for potable there are two small sewage Microtags inserted into young source limitations on some supply abstraction, high class treatment works on the River salmon have allowed the NRA estates. The NRA is investigat­ game and coarse fisheries). Al­ Blackwater, one on the River and the Ministry’ of Agriculture, ing mechanical raking as an together, 135 km o f the 139 km Dever and one on the River Fisheries and Food to investi­ alternative to traditional o f the River Test have this Dun. gate the migration o f adult methods. Scientists are also objective. Wastewater discharged to To achieve these standards, the estuary from the major Fish pass construction the NRA sets limits known as Southampton sewage works at consent conditions on all per­ Millbnx)k and Slowhill amounts mitted discharges, restricting to 49,400 m Vd. their strength and quantity. Water abstracted for various uses and returned to the river FISHERIES amounts to a quarter o f average It is the high quality game total flow and consent condi­ fisheries that have made the tions are stringent to ensure River Test justifiably famous. that re-used water approaches Its chalk water and abundance the natural river water quality. o f weed are ideal for salmon There is little manufacturing and trout. Salmon have been industry on the River Test, the caught as far upstream as Long- only significant discharge in this parish but the main salmon and category being from a paper sea trout fisheries are down­ mill at Overton. It is testimony stream o f Romsey. The middle to the high quality of the river and upper reaches are greatly that its waters are used for esteemed for their trout and as washing and processing the the Mecca o f dry . paper used for British bank Chalk streams support an salmon whilst they are at sea. studying the occurrence, notes! The river has an objec­ abundance o f insects and other Some have been found off movement and source of sedi­ tive o f Class IB (high quality invertebrates upon which the Western Ireland (which is on mentation in the chalk streams. water suitable for game and fish feed. The water contains their route to and from feeding high class fisheries) for the calcium with which shrimps, grounds near Greenland) and 4 km below this discharge. snails and other creatures can as far afield as the Farcxr Islands. FLOOD The largest volume of build external skeletons. Some Most recently, small scale DEFENCE returned water is from the ten eight species o f stonefly radio transmitters have been fish farms in the catchment and nymphs, twenty-two species of attached to salmon to show The porous chalk enables rain watercress farms on the Bourne mayfly nymphs, thirty-eight which reaches of the river the to soak into the ground rather Rivulet and River Anton. The species o f caddis and seventy fish frequent and also where than running overland into the high quality, the temperature other species of invertebrates they spawn. river. Flooding is therefore profile of the river water, and have been recorded from the A problem faced by salmon unusual in the headwaters or proximity to markets make the river. and the native brown trout is on the main river, though valley ideal for these activities The NRA has committed that the gravel areas in which exceptional rainfall of 584 mm which bring economic benefit substantial resources to re­ they spawn have tended to silt. in four months in I960 led to to the area. The effluents must searching the status o f salmon Chalk streams have a natural extensive fhxxling in the Test meet the quality and volume stocks and to their protection. silt load and river keepers Valley and particularly in conditions of NRA discharge Anti-poaching patrols are traditionally raked gravels to Stockbridge. The NRA and riparian owners REFERENCES ‘Survey of Agriculture of regularly cut weed to control Hampshire' ( Vancouver). The Hampshire' collection, The Dorset volume of Land river levels, especially when City Reference Utilisation Survey o f Britain’ rapid growth of water plants in Library. and ’Agriculture' by Lord Amle. spring and early summer Proceedings o f the Hampshire Field Club - particularly coincides with peak flows. TW. Shore, circa 1(MX). During agreed weed cutting periods the NRA operates a weed trapping boom at Tims- bury to minimise blockages of culverts, sluices and grilles downstream. Riparian landowners are responsible for operating and maintaining the many sluices which control the flows through the many carriers and feeder channels which run parallel to the main river channel. The more flashy tributaries like the River Dun and the Blackwater, which drain clay and sandy areas, show more significant flow variations. Floods on the River Dun were caused by snow melt in 1914 and by heavy rainfall in 1974. There is some tidal flooding o f the riverside fields down­ stream o f Testwood Mill during high spring tides where there are no tidal embankments.

Sections showing the general relations of the rocks along the lines Y—Y' drawn on the map

Portsea Ports Down Chichester Ventnor Ryde Spithead Island Anticline Syndine O.O. O.D.

Conjectural base of recent deposits

NRA

National Rivers Authority Southern Region

Headquarters Guildboume House Chatsworth Road

Worthing West Sussex BN11 1LD Purbeck ond Portland Cloygofe Beds and Upper G re e n la n d Beds. Kimmendge (0903)820692 March 1991 0 1 0 2 0 k m London Cloy ond G ault □ ond Oxford Clay

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