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Area Administrative Boundaries
Regional Boundary
Area Office
Regional Headquarters
KENT AREA
SUSSEX AREA
HAMPSHIREAREA
Maidstone
Worthing
Winchester
E N V I R O N M E N T A G E N C YG E N E R A L E N Q U I R Y L I
N E
0845 933 3111
E N V I R O N M E N T A G E N C YE M E R G E N C Y H O T L I N
E
0800 80 70 60
E N V I R O N M E N T A G E N C YF L O O D L I N E
0845 988 1188
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Lymington
Milford-on-Sea
Wes
tern
Yar
Tho rleyBrook
Weste
rn
Have
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Caul
Bour
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Rodge Brook
Rive rM
edina
Palm
er's
Bro
okEa
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nYa
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B la ckbridge Brook
Scot
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s B
rook
Yarmouth
Newport
Cowes
Ryde
Sandown
Shanklin
BrighstoneShorwell
Totland
Freshwater
Northwood
EastCowes
WoottonFishbourne
St Helens
Nettlestone
Bembridge
Ventnor
St Lawrence
Niton
Godshill
Newtown River
Brading
0 5km
N
St. Catherine'sPoint
TheNeedles
The SolentThe Solent
Rive rM
e dina
Woo
tton
Cree
k
Easte
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Yar
Watercourse
Built up area
SSSI
KEY
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Environment Agency - a betterenvironment in England and Walesfor
present and future generations.
The Environment Agency is one of theworld's most powerful
environmentalwatchdogs, regulating air, land andwater. As
'guardians of theenvironment' the Agency has legalduties to protect
and improve theenvironment throughout England andWales and in doing
so contributestowards 'sustainable development' -meeting the needs
of today withoutharming future generations.
Created by the 1995 Environment Act,the Agency started work in
1996. It isofficially a 'non-departmental publicbody', which means
that the
organisation works for the public andhas specific duties and
powers.
Nationally, around 15 million hectaresof land are managed by the
Agencyalong with 36,000km of rivers and5,000km of coastline,
including morethan 2 million hectares of coastalwaters.
There are eight regional offices, whichare split into 26 area
offices. SouthernRegion covers the counties of Kent,Sussex,
Hampshire and the Isle ofWight.
Front cover photographs:Main picture - Eastern YarTop inset -
Godshill ChurchBottom inset - Sea defences Freshwater Bay
R i v e r s o f t h e
I s l e o f W i g h t
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FACT FILES R i v e r s o f t h e I s l e o f W i g h t
History and Geology
Popular as a holiday destination withan ‘abroad feel’ to it, the
Isle of Wightis the largest Island off the Englishcoast. It is
separated from Hampshireby the Solent and bounded by theEnglish
Channel on its south side.
Evidence suggests that the first settlers,the New Stone Age
communities,arrived on the Island sometime after4,000 BC. As the
population expandedlarge areas of woodland were clearedfor
agriculture and by the Middle Agesthe Island had become a
mixedagricultural landscape.
By Tudor times seven deer parks hadbeen created. Queen Victoria
andPrince Albert added their royal seal ofapproval when they made
OsbourneHouse their Island home, causing alarge development of
Victorian villasand gardens to spring up.
The Island formed part of themainland until well after the last
iceage. Despite its small size – 381 km2
(155 square miles) – the Isle of Wighthas a varied geology and
its rocks and
clay contain Europe’s most abundantdinosaur fossil beds.
There are three distinct rockformations, the Tertiary Clays
andSands to the north, the central chalkridge that once connected
TheNeedles to the chalk of the Isle ofPurbeck and the Greensands,
Gaultand Wealden Clays to the south of theisland. These rocks were
laid downover a period of time dating back tothe Cretaceous (135
million years ago)and the Tertiary (65 million years
ago)timescales. The last two million years(Quaternary) complete the
geologicalstory of the island.
The Island’s topography reflects thegeology and forms
distinctive areas ofthe landscape:
● high central ridge of chalk downs and the Southern Chalk
Downs
● the Greensand ridge● northern clay pastures● intensively
managed southern
coastal plains, river valleys and dramatic coastline
Wightlink ferry at Fishbourne
South Wight coast
Main picture: South Wight coast
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Rivers
Apart from a few small brooks on thesouth coast, all the
Island’s streamsflow northwards. Included amongthese are the
Western Yar, NewtownRiver (Caul Bourne) and the
Palmer’s,Blackbridge and MonktonmeadBrooks.
There are five main estuary systems –the Eastern Yar, Western
Yar,Newtown, Medina and WoottonCreek. All share common features
oftidal mudflats and shingle, saltmarshand varying amounts of
fringing
woodlands. The Island’s estuaries arethe remnants of once large
valleysystems that carried rivers into thegreat Solent estuary.
Rivers not fed from the chalk aquiferlike the Merstone Stream or
ThorleyBrook tend to have a ‘flashy’ responseto rainfall and suffer
from naturally lowflows in the summer. However, riversfed by
springs from the chalk likeLukely Brook do not tend to reactrapidly
to rainfall except when coupledwith urban run off.
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Until well after the last ice age the Isleof Wight was part of
the mainland. Amajor trunk stream, the Solent River,flowed
eastwards from the River Fromein Dorset along the line of the
Solentand Spithead, to outfall to the sea inthe Littlehampton area.
Its northerntributaries would have included theAvon, Test and
Itchen and its southerntributaries would have been thestreams which
drained from thenorthern slopes of Purbeck and the Isleof Wight.
The drainage system was
dismembered by the sea breaking intothe main channel between
Purbeckand the Island.
This breach occurred as a result of adepression of the land, or
rise in sealevel, which lasted until about 2000 BCand also led to
the submergence ofthe downstream reaches of the Northflowing
rivers, giving them their wellmarked estuaries. The Harbours
ofYarmouth, Newtown, Cowes andWootton Creek owe their origins
tothis movement.
Wootton Creek
Calbourne Mill
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Medina
The Isle of Wight’s major rivers are theMedina and the Eastern
Yar. TheMedina rises as chalk springs from StCatherine’s Down on
the south side ofthe Island. Medina is a latinised formof its Saxon
name Medene meaningMiddle River. The Medina is 17kmlong, with a
catchment area of 71 sqkm, and flows due north collectingthe
Merstone Stream at Blackwaterbefore intersecting the ridge at
Shide.It is a linear estuary enclosed by a lowvalley with plenty of
industry andshipping and little marginalvegetation.
The Medina’s tributary, the LukelyBrook rises in the Bowcombe
Valleyand joins the river at the head of theestuary in Newport –
the Island’scapital. Lukely Brook is also subject totides and forms
the northern boundaryof medieval Newport. It cuts throughthe chalk
at Carisbrooke where, to theeast of the valley, sits the
famouscastle.
From Newport to the sea at Cowes theriver is tidal.
Lukely Brook at Newport
Newport Quay
Newport Quay
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Western Yar
The Western Yar was once a river witha well developed system of
tributaries,but the erosion of the channel coasthas destroyed its
upper catchment.Protection works now prevent the seaflowing into
the Western Yar atFreshwater Bay - the source of theriver. The
river must once have beenone of the largest on the Island but isnow
no more than a brook with adisproportionately large estuary.
Abalanced landscape of fields, saltmarshand woods all add to the
attractiveness
of the river. Afton Marsh reed bedsdominate the upper reach.
Creation of the harbour andbreakwater in 1843 - seven atYarmouth
did much to change theshape of the lower reaches of theestuary, as
did the building of a tide-mill and sluice gates in 1793 acrossthe
Thorley Brook - the Western Yar’smain tributary. The bridge
andharbour dominate the estuary mouth.
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for agriculture. Bembridge Harbourand the Yar were extensively
modifiedin historic times by the construction ofcauseways, with
land reclamation anddrainage above the causeway to StHelen’s. The
dunes of the Duver are amarked contrast to the seafront andharbour,
while the embankment of theYar upstream provides an unusual
andattractive landscape of wet grazing.
Eastern Yar
The Eastern Yar is 27 km long andflows north east from springs
at StCatherine’s Down collecting theWroxall Stream, Scotchell’s
Brook anda number of small tributaries beforecutting through the
central chalk ridgeat Brading. Until the 16th century theEastern
Yar flowed into the sea at bothSandown and Bembridge. The wholeof
this saltmarsh has been reclaimed
Western Yar at Freshwater Nature Reserve
Thorley Brook
Yarmouth Mill
Eastern Yar - Longbridge
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Greensand Groundwater Scheme andthe Medina Yar Transfer Scheme
whichtakes groundwater from the LowerGreensand and transfers it to
theMedina.
Water is then transferred from theMedina to the Yar to allow
abstractionfrom the Yar at Sandown.
In 1988 the Island was chosen as thelargest pilot scheme area
for meteringwater. Since the installation of watermeters at more
than 51,000 homes,demand has reduced by 20%.
Water Quality
The Environment Agency has aresponsibility for the water quality
ofall controlled inland waters and coastalwaters up to a limit of
three nauticalmiles offshore.
Water quality is assessed by takingsamples of water and
measuring the
Water Resources
The Environment Agency balancescarefully demands for water and
theneeds of the environment through anabstraction licensing
system.
Water is abstracted from the Island’srivers and groundwater for
a range ofuses including public water supply,agriculture and
industry. Conditionsmay be attached to the licence toprotect the
rights of existing users andensure that the water environment,such
as river flows and wetlands, arenot unacceptably affected.
The major aquifers on the Island arethe Chalk, the Upper
Greensand andthe Lower Greensand. Abstractions forpublic water
supply are from the twolargest rivers, the Eastern Yar
andMedina.
Demand for public supply is thegreatest stress on water
resources with86% of all licensed groundwaterabstraction for public
supply. Nearly57% of surface water abstraction isalso for public
supply.
In the past the Isle of Wight sufferedwater supply problems due
to itslimited surface water sources and highsummer population. New
sources ofsupply were developed including theCross-Solent Main,
which involvespumping water from TestwoodReservoir in Hampshire.
The Lower
Spray irrigation
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water service companies have agreedto implement over a five year
period.The Agency, OFWAT and the DrinkingWater Inspectorate all
have input intothese plans.
The natural quality of the streams isvariable. Those arising
from chalksprings are well buffered and neutral,whereas those
originating from therich sandstones may be acidic andrusty deposits
can be seen on graveland vegetation. An example of thiscan be seen
between the River Medinaand the Merstone Stream where theymeet at
Blackwater. Iron depositsvividly stain the bed of the
Merstone,draining from the Ferruginious Sandsof St George’s
Down.
concentration of chemical pollutantswhich they contain. In
addition,samples of the creatures which inhabitthe bed of the
streams are taken toassess the health of the river.
As well as ensuring the suitability ofwater as a natural
habitat, the Agencymust also ensure the quality of waterand resolve
the many conflictingdemands made by society for drinkingwater,
agriculture, industry, sewagetreatment, fisheries and
recreation.
A close working relationship betweenthe Agency and local
authorities andorganisations is vital to ensure thatwater quality
objectives are consistentand complement one another.
AssetManagement Plans (AMPs) arestrategic investment programmes
that
Southern Water - Seaclean Wight
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The Island’s rivers are mostly of goodwater quality, while
groundwater is ofaverage quality. Particular stretches ofrivers
periodically have poor waterquality, caused by specific
discharges(eg from sewage treatment works).Tidal and estuarine
waters aregenerally of good quality.
There is very little industrial dischargeand most water quality
problems resultfrom surface water which has beencontaminated with
oil before beingdischarged from drains. In particularthe
Scotchell’s Brook at Sandownreceives significant diffuse pollution
asa result of run-off from urban areas. Inrural areas there are
occasionalpollution incidents from septic tanks orfrom farm slurry
and silage. Otherproblems that can occur affectingwater quality
include failure of sewagetreatment works (there are 23 on the
Island), leachate leakage from landfillsites, pollution from
construction sitesand pesticides and nitrates.
The majority of water quality problemsoccur on the clay soils of
the northernhalf of the Island where domesticseptic tanks can cause
problems. Mostlivestock farming is carried out onthese less well
drained soils and thenumber of agricultural pollutionsoccurring in
these areas reflects this.The Agency is working in partnershipwith
a number of organisations,including the IOW Council, Island2000,
NFU, English Nature andSouthampton University to try andtackle the
problem of diffuse pollutionon the Eastern Yar. Prompt reportingof
pollution incidents by environmentconscious Islanders enables the
Agencyto take early action.
Conservation
The Environment Agency has a duty topromote conservation and
often workswith other organisations to further thisend. It is
currently working with theIsland’s Biodiversity Action
PlanPartnership which aims to safeguardkey species and habitats.
The Island isof great natural interest with importanthabitats that
support a number of rarespecies.
Key habitats include chalk grasslandand coastal areas. Coastal
habitats arediverse with several internationallyimportant areas
including saltmarshes,estuaries, saline lagoons, sea caves
andsandflats.
Parkhurst Forest is a fine example ofancient woodland and there
areseveral extensive areas of naturalgrasslands particularly on the
heavy,poorly draining soils around NewtownHarbour.
The rivers of the Isle of Wight are smallcompared with those on
the mainland.They may have been modified by riverengineering
causing a lack of naturalfeatures like pool and riffle sequencesand
meanders. However, in a numberof areas the rivers support a
diverseaquatic flora – more common speciesinclude fool’s
watercress, water mint,yellow flag and less common specieslike
marsh mallow.
Some wetland species are protected byInternational nature
ConservationDirectives and are found around theIsland’s coast with
concentrations inand around the estuaries.
Nationally important mammals to befound are red squirrels and
dormice.Twelve out of fifteen British bat specieslive in the
island’s woodlands. Dartfordwarblers nest in the gorse covereddowns
while the heathland gladesattract breeding nightjar, barn
owls,wintering waterfowl and waders.
Western Yar marshes
South Wight coast
Seaclean Wight
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The slumping coastal cliffs support theonly persistent
population of Glanvillebutterflies in Britain.
The Island has a large number andarea of European
designatedconservation sites. The Solent andSouthampton Water
Special ProtectionArea (SPA), (notified under the ECDirective on
Wild Birds), includesseveral Isle of Wight SSSIs and has alsobeen
designated a Ramsar Site. TheIsland contains four candidate
SpecialAreas of Conservation (SACs),designated under the EC
HabitatsDirective: the Solent Maritime; SouthWight Maritime; the
Isle of WightLagoons; and the Isle Wight Downs.There are 43 Sites
of Special ScientificInterest (SSSI) and 22 of them arewater
dependent. The Isle of WightArea of Outstanding Natural
Beauty(AONB) covers about half the island(189 sq km), taking in
almost all of thesouth and west. Two stretches ofcoastline are
designated HeritageCoasts and both are in the AONB.They are the
Hampstead HeritageCoast around Newtown (length 10.8
km) and the Tennyson Heritage Coastfrom Totland to Ventnor
(length 34.8km).
Chines are special features of theisland’s landscape. They are
theremains of ancient river valleys,although now are mostly steep
gulliesleading down to the sea. Rich ingeological and ecological
interest, themajority of Chines can be found alongthe Island’s
south west coast. TheEnvironment Agency in partnershipwith the
Island 2000 Trust wonrecognition for their enhancement ofthe
Chines.
A section of the Eastern Yar atLangbridge has undergone
habitatimprovement with advice and helpfrom the Agency. Once a good
coarsefishery and haven for kingfishers andwatervoles, the water
had becomebadly overrun with small trees causinga decline in the
habitat value of theriver. A tree management plan to keepthe trees
in check and maintain variedhabitats benefits local bird,
fish,mammal and invertebrate populations.
Newtown Upper Reach
Eastern Yar at Longbridge
Lukley Brook
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Bembridge Harbour
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The Island attracts national andinternational attention from the
sailingfraternity. Specific events includeCowes Week, the
International PowerBoat Race and the Round the IslandRace. Cowes
located at the mouth ofthe Medina is home to the Royal
YachtSquadron and other yacht clubs. Awide range of moorings,
equipmentsupply and boatyards can be found atCowes, Bembridge
harbour, WoottonCreek and the Medina estuary.
There are no navigable inlandwaterways on the Island.
Canoeing is also popular and there arefour main sites at Newtown
Harbour,the River Yar, Yaverland and
Dunroamin. Yaverland and Dunroaminbeaches are also
importantwindsurfing spots along with GurnardBay and the Esplanade
at Sandown.Yaverland is also the Island’s mainwater skiing and sub
aqua site.
The Island boasts 500 miles of walks -many along rivers and
streams andthere are also plenty of opportunitiesfor cycling.
Fisher ies
It is a key aim of the EnvironmentAgency to ensure that all
waters onthe Isle of Wight are capable ofsustaining healthy and
thriving fishpopulations.
Potential for coarse fishing is limitedbecause of the small size
of the Island’srivers. Carp, roach and dace are thepredominant
species of coarse fish onthe Island. Rudd, perch, bream andtench
are found in small numbers,while minor streams are characterisedby
stoneloach, bullhead and eel. Otherspecies to be found
includestickleback, gudgeon and brooklamprey. Roach and eel are the
mostabundant species caught in the CaulBourne.
Under the EU Freshwater FisheriesDirective the Eastern Yar
betweenHorringford and its mouth and theMedina between Chillerton
andNewport are designated as CyprinidFisheries. This reinforces the
water
quality standards to which the riversmust be protected.
The Eastern Yar and River Medina bothhave populations of small
wild browntrout, characteristic of chalk streamheadwaters.
Occasionally, there havebeen reports of sea trout in theMedina
estuary, but these have notextended above Newport.
There are around 30 privately ownedstillwater lakes and ponds
fished onthe island and the majority of thesesupport major coarse
fish species.
Recreation
Surrounded by water andgeographically placed in one of
thesunniest parts of Britain, the Isle ofWight is a Mecca for
tourists -attracting 2.3 million visitors a year.It’s popularity as
a seaside resort goesback to Victorian times when theIsland was
given the royal seal ofapproval by Queen Victoria and
PrinceAlbert.
Wootton Creek
Railway bridleway
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1918
Flood defence
The Environment Agency has duties toprotect people and property
fromflooding from rivers and the sea.
There are 114 km of main river on theIsle of Wight for which the
Agency hasflood defence responsibility. Riversystems of the island
are typically smallhill streams rising at the base of thechalk
beneath the Downs. Periods ofhigh flow are short lived but
peakflows are high.
In the past, the Island’s opencountryside allowed more rain to
soakinto the ground slowing down runoffand allowing rivers to rise
slowly.Conversion of pasture to arable landhas meant water now
enters the rivermore rapidly through furrows.Additionally, river
engineering andbuilding in the floodplains have allhelped to
accelerate the rise in riverwater levels during heavy rain.
TheAgency discourages development inthe floodplain and actively
promotes
sustainable drainage systems whichslow down the passage of rain,
fromthe land to the rivers.
The greatest part of the EnvironmentAgency’s major flood defence
work onthe Island is on the tidal reaches of therivers.
Flood alleviation schemes in the pastwere carried out at the
Schoolgreenarea of Freshwater on the Western Yar,a 4 km stretch of
the River Medina,Lukely Brook between TowngateBridge and
Westminster Mill, ShalfleetMill Stream, Thorley Brook and on
theEastern Yar between St Helens andSouthford Mill.
Monktonmead Brook at Ryde has along history of flooding dating
back100 years. In 2001 the Agencyannounced a £750,000 scheme tomore
effectively release floodwaters tothe sea by extending the
concreteoutfall and installing two new, highcapacity pumps to
further relieve thepressure at very high tides
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Main picture: River Yar tidal banks
Sandown sea wall
Sandown sea wall
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River Maintenance
River maintenance plays an importantpart in reducing the risk of
flooding. Aprogramme of annual maintenance iscarried out by the
Agency’s Hampshireand Isle of Wight Direct Works Force.Removal of
debris likely to blocksluices, culverts and weirs is vital.
Alsoimportant is the clearance ofovergrown bankside vegetation
anddredging works to maintain constantflows.
Careful checking and monitoring ofman-made flood defences is
routinelycarried out
Preventing Pollution fromWaste
The Environment Agency works withothers to ensure that
controlled waste– waste produced by offices,businesses, factories,
schools andshops amongst others – is handled,transported, treated
and disposed of assafely as possible.
Safe disposal of waste costs moneyand some people try to avoid
thesecosts by dumping their waste illegally.This is known as fly
tipping. It isunsightly, but more importantly it cancause
significant health problems forrivers, wildlife and the
surroundingenvironment. Anyone caught flytipping will be prosecuted
by theAgency.
Putting waste into landfill sites cangenerate landfill gas – a
greenhousegas – and liquid leachate, which, ifallowed to escape,
can contaminatewater and harm humans and wildlife.
Lynnbottom Landfill took the majorityof the Island’s waste. When
thatbecame full a new site was built atStanden Heath not far from
thePalmer’s Brook. The Agency works withthe developers to ensure
that the siteengineering and environmentalmonitoring safeguards
thewatercourse.
There are a number of waste facilitieson the Island, some of
them nearrivers and streams, all carefullymonitored by the
Agency.
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Eastern Yar sluices
Amenity site
Landfill operations
New landfill cell and drainage
Photographs by John Chandler