0

InstituteofFreshwaterEcology

Ecological Survey of the River Teign atCastle Drogo, Devon

M GraveIle,BSc, MScP Scarlett, BSc, MScA T Ibbotson, BSc, PhD, Grad IPM, MIFMF H Dawson, PhD, CBiol, MCIWEMJ H Blackburn, BSc

Report to:Report Reference No:

Dulas LtdT0407307/3

•"

Natural Environment Research Council

á

Institute ofFreshwaterEcologyRiver LaboratoryEast Stoke, WarehamDorset BH20 6BBUnited Kingdom

Telephone +44 (0)1929 462314Facsimile +44 (0)1929 462180Email

Ecological Survey of the River Teign at Castle Drogo,Devon

M Gravelle,BSc,MScP Scarlett,BSc,MScA T Ibbotson,BSc,PhD,GradIPM,MIFMF H Dawson,PhD,CBiol,MCIWEM

H Blackburn,BSc

Project Leader: F H DawsonReport Date: August 1997Report to: Dulas LtdIFE Report Reference No: T04073G7/3Project No: T04073G7

Centre forEcology &Hydrology

Institute of Freshwater Ecology

Institute of Hydrology

Institute of Terrestrial Ecology

Institute of Virology & Environmental Microbiology

Natural Environment Research Council

INTELLECTUALPROPERTYRIGHTS

CONFIDENTIALITYSTATEMENT

'In accordance with our normal practice, this report is for the use only of the party towhom it is addressed, and no responsibility is accepted to any third party for thewhole or any part of its contents. Neither the whole nor any part of this report or anyreference thereto may be included in any published document, circular or statement,nor published or referred to in any way without our written approval of the form andcontext in which it may appear.'

EcologicalSurvey of River Teign at Castle Drogo, Devon.28/08/1997 2

1. Introduction.

1.1 Background to survey.

Water has previously been abstracted from the River Teign, Devon to generateelectricity for use at Castle Drogo. The abstraction took place between 1928 and 1993,although only the smaller of the two turbines where in operation since 1980.

A weir on the River Teign (SX 72258965) retained water for abstraction to the turbinehouse, from which the water was returned to the river approximately 500 metresdownstream of the weir (SX 72978974). The reach between the weir and the turbinehouse has therefore been subject to reductions in flow during the operation of thehydroelectric scheme.

It is now proposed to reinstate both turbines which would require abstraction from theTeign.

1.2 Objectives of the project

The objective of this project was to conduct an ecological survey of 1.5 kilometres ofthe River Teign where it flows through the Castle Drogo estate. This continuoussurvey length included sections upstream and downstream of the impacted section.

The ecological survey included macrophyte, invertebrate and habitat surveys butexcluded fisheries investigations.

The results of the survey have been used to assess the historical impacts of thehydroelectric scheme and to assess the most suitable of two abstraction regimes to beused for reinstatement of the turbines. The information will be used by Dulas Ltd aspart of an Environmental Statement accompanying the application for an abstractionlicense.

1.3 General description of site.

The river Teign has its source on Dartmoor and flows.through Dartmoor NationalPark for approximately 15 kilometres before reaching the Castle Drogo estate. In theupstream end of the survey area the river flows through a shallow concave valley withgrazed fields on either bank. Within a few hundred metres the river enters a muchsteeper valley with broad-leaved woodland on both banks. These woodlands are ofhigh conservation value, particularly Whiddon Park which has been notified as a Site ofSpecial Scientific Interest, being outstanding examples of ancient oak and ashwoodland.

The river has a cobble and coarse sand substrate with many exposed boulders and adiversity of flow types. There are numerous mature islands in the survey reachincluding one approximately 150 metres long. The instream habitats are fairly diverseand there are a limited number of hydraulically linked habitats created from the cut offof old channel courses.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 3

2. Methodology.The portion of the River Teign which flows through the Castle Drogo estate wasdivided into three reaches of approximately500m banklength for the purposes of thisstudy. Within each reach a River Corridor Survey (RCS), a River Habitat Survey(RHS), an invertebrate sample and a macrophyte survey were completed.

Photographs of each reach were taken to represent the general character and one ofeach of the macrophytesurvey points were also taken.

Reach OneThe downstreamend of reach one was the top of the weir from which water wasabstracted for the hydroelectric scheme (SX 72258965). The reach extended for 500mupstream to SX 71908940.

Reach TwoThe upstream limit of reach two was the weir (SX 72258965) and the downstreamlimit was the outfall channel from the turbine house (SX 72538990). The total lengthof this reach was approximately450m.

Reach ThreeThe third reach extended for 500m downstream of the turbine house (SX 72538990 toSX 72978974).

Hydrologicaldata suppliedby Dulas Ltd were used as the basis for assessing thedifferent abstractionregimes. The data are based on average daily flows for sevenyears (1988-1995) from a gauging station further downstream on the Teign, at Preston(approximategrid reference SX 855745), multipliedby a factor of 0.382.

A report producedby the National Trust (1990) was available to provide someadditional ecologicaldata This report detailed findingsof surveys in 1990and 1979from the Castle Drogo estate and included a short section on the flora and fauna of theriver itself

2.1 River Corridor Survey.

One RCS surveymap was produced for each reach following the methodology set outin River Corridor Surveys: Methods and Procedures (NRA, 1992). The survey wascompleted fromboth banks and the river channel.

Due to the densely wooded river banks and corridor it would have been difficult andtime consumingto map the location of every tree, particularly for reaches 2 and 3, andso a general outline of the wooded area was used, with overhanging trees and thoseseparated from the rest of the canopy marked individually.

The RCS was used to identify and locate any habitatsor areas previously impacted orat risk from abstractionfor the scheme.

Ecological Surveyof River Teign at Castle Drogo, Devon.28/08/1997 4

2.2 River Habitat Survey.

The RHS was completed by an EA accredited surveyor following the standardmethodology as detailed in the 1997 Field Survey Guidance Manual (EA, 1997a). Thesurvey was completed using the new 1997 forms and incorporated SERCON (Systemfor Evaluating Rivers for Conservation).

Comparisons were made between the RHS surveys for the three reaches and rivers ofthe same segment type (classification of rivers and streams based on geology, altitude,slope and flow category data) from the national data set. A Habitat Modification Index(HMI) and a Habitat Quality Assessment (HQA) score were also calculated frompreliminary guidelines produced by the Environment Agency (EA 1996 and 1997b).

The HMI provides a measure, on a scale or 0-100, of the naturalness of the river reachby assessing the extent of resectioning and reinforcement of the banks and channel andthe number of artificial features recorded. A high score (near or over 50) indicates ahighly modified river whilst a score of 1 or 2 indicates a semi-natural river.

The HQA is a simple scoring system using the presence and extent of natural featuresto provide a system for comparing RHS sites. The scores used here were calculatedfrom the first working version presented in the River Habitat Survey newsletter 5 (EA1997b).

2.3 InvertebrateSurvey.In each reach a three minute kick sample was carried out following the standardmethodology for RIVPACS (River Invertebrate Prediction and Classification Scheme).Each of the habitats within the reach was sampled in proportion to the percentage ofreach they occupied. Thus instream vegetation, bankside tree roots and boulders weresampled in addition to the predominant substrate (cobble and sand) and the sectionselected represented the diversity of flow types found within the reach.

The samples were immediately preserved in formaldehyde and later sorted andidentified by an experienced and accredited (Natural History Museum IdQ examinationE062 - Freshwater macro-invertebrates) biologist at the laboratory. Identification was tospecies level where possible for all specimens except oligocheates and chironomids.

2.4 MacrophyteSurvey.A 20m (banklength) of each reach was selected for a macrophyte survey. The sectionwas chosen to include representative habitats of the full 500m reach. The full channelwidth and all boulders or parts of the bank regularly inundated by water(approximately 20cm height above the water level at the time of survey, as indicated bythe vegetation observed) were included in the area surveyed. The percentage cover ofeach species present within this section was estimated.

The upstream and downstream limits of each section were marked by a metal stakewith a flat, white top set flush to the ground. The location of these markers were notedand photographs taken to aid relocation (the photographs have been delivered to DulasLtd as 35mm transparencies).

Ecological Survey of River Teign at Castle Drogo, Devon.01/09/1997 5

The macrophyte transect in reach one was completed just downstream of the bend inthe river, with the upstream end being marked by the telegraph pole on the left bank. Inreach 2 the survey location was downstream of the mature islands. The third transectwas located just upstream of a fence perpendicular to the left bank. All markers wereset in the bank, generally near trees to partially hide them from casual observation.

In addition to the 20m section any other species observed over the whole reach werenoted as present.

Identifications of all moss and liverwort species and some other macrophytes wereconfirmed upon return to the laboratory and herbarium samples retained in the 11-thcollection at the River Laboratory.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 6

3. Results.

3.1 River Corridor Survey.The maps for the three sections are shown in figures la-c and the summary sheets inappendix 1.

The most notable differences between the reaches were caused by the weir whichcreated a stretch of slow flowing, relatively deep water in reach one for a distance ofabout 150metres. The upstreamreach (one) was also significantly less shaded due tothe more open valley form and absence of broad-leaved woodland.

Reach three had the most diverse natural habitats due to the presence of several matureislands in the lower 100metres. These created different flow patterns including severaldeep still pools and high energy rapids. There was also an abundance of woody debriscaught against boulders and the edges of the islands.

The middle reach had one large mature island in the centre but there was very littleflow around the right bank side. There were also several old channels dissecting theisland which are now quite silted and dry. Within these channels and a similar one onthe right bank there were pools of standing water in which some green algae andtadpoles were observed. Together with a small pond on the left bank and a spring atthe extreme downstream end of the reach these are the only habitats in hydrologicalcontinuitywith the river itself

Alnus glutinosa (alder) was common along both banks of all three reaches as wereseveral other tree species. Dippers and grey wagtails were observed along the riverlength and salmon were seenjumping up the fish ladder.

EcologicalSurvey of River Teign at Castle Drogo, Devon.28/08/1997 7

River Teign

Reach I .

Name: Michael Gravel le

Date: [2/6/97Abstraction point

Paru,

. !. i

"

0 1 'Or%%N.1

Tree stump . v,..,

Rpen "el‘ !• el Fsqua,

Z., i

Aglu %.'„ apt'V

Old reinforcement ": 4 , -ire-x.......K Small area of standiag(dry stone wall)

OCIti‘, ....................----- water, with Cpal.

,[BLI Fsqu la %

Igla• . A \Ni t __1(....ler. • i% \ el ' ... Fsqu

Width restricted by boulde %,"te ili,`"ARPen

TTCham

-615

%. BAglu, Fexc, Apse,

"E' k 7 % lir t2c5 • Qpet and Salix sp

Rpen /

Aglu, Fexc, ApsuA \' , , 1\17\1\ 6' '

and Qpet. e, Rpen'q. hamB Ocro t ,% .q

Malt"q , zI I tee..A a 1

2m Aglu • asect,". FsquI v Os.4---- IOM --- 450

2m I ftis a0.35m i1

f - V AI ; Farm bridge

SX 72258965

•

•

Fishermansplatform

[BLJ

Cham

50 ETA

rn

I.6m

Aglu. Fexc, Apsuand Qpet.

ChamFsqu

ApsuOcro

•RpeCham

Aglu

Cobble/sand depsit .02. •

(SG]ro

Aglu. Fexc, Apse,Qpet and Salix sp.

(SGI

•:Ocro

AgluFeXC

/

Vegetatedside bar—x I

SX 7 [908940

Rpen

riff Fsou

Aglu

Figure la. River Corridor Survey map for Reach I of the river Teign, Castle Drogo, Devon.

River Teign

Reach 2

Name: Michael Gravel le

Date: 12/6/97

Small pond SX 72538990

AgluSmall spring and stream

[Openwoodlandwithgrassand tallherbsunderstorey]

Ocro Turbine house

PamSand deposits across outfall

-fru

15°

I 0.65m9m

1.7m 9,0 0

Old channel - sandy bed quite overgrownwith mosses and Luzula spp.Standing pools in parts with green algae,Chun, Fant, Paru and tadpoles

Qpet

I % C3iei

-,

i ,

tftta ': [B14tY .a2

0.40mA -

FexcOcro

I

1 %

[B14Fexc

A

0.40m

Ocro

Aglu

Fexc

50 m

10 m

Woody debris forming

partial damFsqu.Rrip +Aflu

Densly wooded islands

Tall cliff (c3m)•

Aglu

[BUJ

9Old channels - partly silted

`, and dry at time of survey

'

Almost no flow through side channel

farglu Cobble/boulder substrate with abundant

mosses

Predominately broadleaved woodlandon island

Fsqu

t \S\Rpon altx sp

Salix s • OcroAglu Fsqu

kkk\ k

Ocro

•Ocro

Woody debris 6

ittt [BLI

SX 72258965

N N,Weir with fish ladder.Aglu

Fsyl

Figure I b. River Corridor Survey map for Reach 2 of the river Teign, Castle Drogo, Devon

River Tcign

Reach 3

Name: Michael GraveHe

Date: 12/6/97 SX 72978974

Densly shaded

50 in

I rn

Ocro '

Aglu

Ocro

Dense shading'U.

?13. FsquFsyl IL?Aglu

i .

p A Fexc ‘t 4

tJU1

I

Fsqu

•

squ

Rpon

Accumulation of

woody debris

Bedrock channel

substrate

Boulders restricting

, channel width

QPet

Fcxci '

Remnantchannel now Aglu:

dry and vegetated•

Cham -

RPen , .‘5°Fsqu ,

I ,t it

Aglu

Apsu .ao

AgluFr: a

SLa.,Ocro 2 0.6mt* m

,I 80° 9.5m

icy, B 4--AgluFexc \S alix sp 0.35m

3mi •

Aglu

Dense shade

A

Ocm

0.6m I .8m

lm

etFsqu

Tts.

Exposed sand and cobbles

Bedrock .ca

7 46%SX 72538990

Wider than d/sTurbinthouse

Figure lc. River Corridor Survey Map for Reach 3 of the river Teign, Castle Drogo, Devon.

Key to River Corridor Survey maps (Figures la-c)

CodeAfAgluApsuChamCpalFexcFsquFsylIglaMaltOcroParuQpetRpenRponRripUeur

S eciesAmblystegium fluviatileAlnus glutinosaAcer pseudoplatanusCallitriche harnulataCaltha palustrisFraxinus excelsiorFontinalis squamosaFagus sylvaticaImpatiens glanduliferaMyriophyllum alterniflorumOenanthe crocataPhalaris arundinaceaQuercus petaeaRanunculus penicillatus subsp penicillatusRhododendron ponticumRhynchostegium ripariodiesUlex europaeus

Common name

AlderSycamoreWater star-wortMarsh marigoldCommon ash

Common beachHimalayan balsamWater milfoilHemlock water-dropwortReed canary grassSessile oakWater crowfootRhododendron

Gorse

CHANNELFEATURES

‘L----1" Bridge(road/track)

Footbridge

Lock

Inlet

Weir

Pool

Riffle

Rapids

Run

Waterfall

Protruding rock

Island (withvegetation)

Direction of flow

SURVEYINFORMATION

Direction ofsurvey/bank usod

C-) Photograph

SUBSTRATE

Mud

Sand

Bareshingle

0.. •

co 00* o

CHANNELVEGETATION

Emergent Monocots

X_ Emergent Diem.

"1""" SubmergedMonocou

SubmergedDicots

-COL OrYolohTics

-in Floating leaves

BANKFEATURES

Base of bank

Top of bank

Slump

Stable earth cliff

Erodingearth cliff

Rock cliff

Artificialbankprotection

Cattle drink

\ Shelf / benn

Wa Spring / flush

Inflow stream

/ U \ Outfall

,V1/40///1/,/Dredgings/spoil

ADJACENTLANDFEATURES

Fence

Gate

Road / track

UuutmnmRailway

VEGETATION

Trees

11111 Conifer

Broadleaf

ovcrhanging

_ fallen

- exposed rool

Woodland •symbol for tyi

P 9mbol Pollarded tree

(P)4. sym bolTree needspollarding

C+ symbol Coppiced tree

Sapling

Sirebsfledgerews

C7 Shrub (single)

WM/ft Dense shrubs

/////// Sparse shrubs

c=z) Hedgerow

fajCp Hedgerow wit,trees

mm

aa.a

Vegetatedshingle

Cobbles

Boulders

uvvv\r•v.v..

VC/WV

CISECIEI

tot

-a-- — Power lines

M221 Building

S.T.W. Sewage works

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997

Grassesowlkerbs

WSW Reed / sedge

Tall grass

Tall herb /ruderal

Tall grass withherbs

I I

3.2 River Habitat Survey.The original RHS forms are included in appendix 1.

Table 1 presents the preliminary Habitat Modification Indices (HMI) and HabitatQuality Assessment (HQA) scores calculated for each reach together with the segmenttype.

Table 1.Habitat indicesand segmenttype of reaches on the river Teign usingRiver Habitat Survey data.

Reach 1 Reach 2 Reach 3Habitat 9 7 1Modification Index slightly modified v. slightly modified semi-natural

Habitat Quality 35 48 41Assessment

Segment Type 2 2 2

lowland cobbly lowland cobbly lowland cobbly

river river river

Reach 1 is slightly more modified than the other reaches with some old reinforcementof the banks recorded. There is also a modest degree of modification on reach 2 duelargely to the weir and turbine house.

The HQA score is highest for reach 2 due to the presence of several mature islands, adiversity of substrate and flow types and a natural side channel. Using the criteriapresented in Table 2 this reach is of nationally outstanding quality, having at least onefeature in each column of the table. Reach 3 also qualifies using these criteria but reach1does not fulfil any of the channel criteria.

Table 2. Qualifyingcriteria for nationallyoutstanding quality (reproduced fromEA, 1997c).

Channel Ri arian AcracentWaterfall > 5m Semi-continuous, or Extensive broadleaf (or

continuous, trees on both native coniferous)Braided or side channel banks woodland or wetland on

both banks, or combinationDebris dam(s) Continuous peat banks in of both

blanket bog areas whereMature island trees would not naturally Ox-bows or abandoned

occur channelsSink holes

'Floating' reed fringes

The habitat quality of all three reaches is high with relatively little modificationrecorded.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 12

All three reaches have more boulder and cobble substrate than the national average forsegment 2 rivers and fewer of the other substrate types (Figure 2). The river substratewas a mixture of cobbles and coarse sand, with cobbles generally predominant. Thehigh proportion of boulder substrates in the river is also reflected in the extent ofexposed boulders, which were recorded as extensive in all three reaches on the Teign.Nationally they have been recorded at 30% of RI-1Ssites (present or extensive).

10

9

8

7

6

5

4

3

2

1

0u, cu 0-5. 1..,ov

o..7:; .c)-o

L0I JD7 0

PP 0PP C) to

>cc:6

Substrate

Figure 2. Frequency histogram of the substrate types recorded at spot checks forthe RHS survey (1996 national average for type two rivers, and three reaches onRiver Teign, Castle Drogo)

The flow types recorded are similar to the national average but with slightly moreoccurrences of rippled flow (Figure 3).The number of riffles recorded in reach 2 and 3,16 and 20 respectively) were significantly greater than the national average (3.6 ± 9.2(p = 0.05)). Ten riffles were recorded in reach 1 which is also higher than the nationalaverage.

The river Teign sites have more trees along the banks and more broad-leavedwoodland within 50m of the bank top than the national average. Only 25 percent ofnational sites have continuous bankside trees and 40 percent have broad-leavedwoodland recorded on either bank (present or extensive). Both these features wererecorded as extensive on all three reaches.

Nationally otters, dippers and grey wagtails were each recorded at seven percent ofsegment two rivers. Both dippers and grey wagtails were seen frequently during thetwo days field work and a salmon tail, probably left by an otter was found at thedownstream end of reach 3.

Number

ofspot

checks

• National average

Reach 1

Reach 2

ISReach 3

Cu chcn

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 13

10

9

8

7

6

5 • National average

4 a Reach 1

3 Dkeach2

2 E Reach 3

02 .0 0 0 em

.c, 46 > c >.c 0 9 '3* 2ti c; -T"U _cU -.- to 0 to 3$-,

2 c .n c a

1g461

Flow type

Figure 3. Frequency histogram of the flow types recorded at spot checks for theRHS survey (1996 national average for type 2 rivers and three reaches on RiverTeign, Castle Drogo)

3.3 Invertebrate Survey.The full list of species recorded in the three reaches are included in appendix 2. Thefamiliesand numberof individualsin each sample are shown in Table 3.

Fewest families were recorded in reach two (23), with similar numbers in the other tworeaches (31 in reach one and 28 in reach 2). The total number of species recorded isalso fewest in reach two, as are the number of individuals.These difference wereconsidered to be due to samplingerrors caused by only taking a single sample in eachreach.

Some differenceswere apparent in the presence or absence of families (and species)and in the abundanceof families (and species) in each reach although these were alsoconsidered to be due to sample error rather than ecological differences. Theimpoundmentof water in reach one had a small affect on the species recorded, withSigara venusta and Plea leachi, species particularlytypical of slow flows/still water,only recorded in the upstream reach.

Number

ofspot

checks

0

0.0)

o.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 14

Table 3. List of invertebrate families, with number of individuals, recorded in a 3minute kick sample in each reach of the river Teign, Castle Drogo.

Number of individuals in sam leFamil Reach 1 Reach 2 Reach 3Agriidae 1

Ancylidae 5 24 16Baetidae 56 136 184Brachycentridae 32 24 56Ceratopogonidae 16

Chironomidae 256 184 440Chloroperlidae 6

Cordulegasteridae

1Corixidae 1

Dytiscidae 3

Elminthidae 89 36 27Empididae

10

Ephemerellidae 440 976 1088Ephemeridae 1

Gammaridae 3

Glossiphoniidae 4

1Goeridae

1

Heptageniidae

1Hydracarina 16 8 8Hydrobiidae 448 12 48Hydrophilidae 40 1 2Hydropsychidae 8 64 24Lepidostomatidae 56 16 24Leptoceridae 80 2 6Leuctridae I

1Limnephilidae 8 2 9Lymnaeidae 6

4Odontoceridae

1 1Oligochaeta 48 80 168Philopotamidae

1Planariidae

3Pleidae 1

Rhagionidae 6 16 1Rhyacophilidae 9 38 45Sericostomatidae 24 16 2Simuliidae 232 32 128Sphaeriidae 32

7Tipulidae 34 8 25Veliidae

1

Total No. of families 31 23 28Total No. of species 43 29 39Total No. of individuals 1962 1701 2321

EcologicalSurveyof RiverTeignat CastleDrogo,Devon.28/08/1997 15

3.4 Macrophyte Survey.Table4 liststhespeciesrecordedineach20 metresectionandTable5 listanyadditionalspeciesnotedin the500metrereach.

Table 4. Percentagecover of macrophytesrecorded in 20 metre sectionsin eachreach of the River Teignat CastleDrogo.

Species Commonname

Percenta e Cover Reach 1 Reach 2 Reach 3

(u/s (weir to (d/sweir) turbine turbine

house) house)Amblystegium fluviatile (Hedw.)

0.5 0.5Apium nodiflorum (L.)Lag. Fool's water-cress < 0.1 < 0.1

Callitriche hamulata Kutz.ex W.D.J.Koch Waterstarwort 1.5 0.5 0.5Caltha palustris L. Marsh-marigold

0.5Chiloscyphus polyanthos (L.)Corda

< 0.1 0.5Conocephalwn conicum (L.)Underw.

1

0.5Fissidens viridulus (Sw.)Wahlenb.

< 0.1Fontinalis squamosa Hedw.

5 15 20Mnium hornum Hedw.

0.5

Myriophyllum alterniflorum DC. Waterinilfoil < 0.1

Oenanthe crocata L. Hemlockwater-dropwort 1 10 0.5Phalaris arundinacea L. Reedcanarygrass

< 0.1

Ranunculus penicillatus subsppenicillatus Watercrowfoot 5

< 0.1(Syme)S.D.Webster

Rhynchostegium riparoides (Hedw.)Warnst.

1 0.5 0.5Riccardia chamed olia (With.)Gott.

< 0.1 0.5 0.5Totalcover

15 28 24Totalnumberof s ecies

9 10 11Totalnumberofbryophytes

4 6 7

Table 5. Additionalspeciesobservedin each reach of the River Teign, CastleDrogo.

S eciesCaltha palustris L.Chiloscyphus polyanthos (L.)CordaFontinalis antipyretica Hedw.Iris psuedacorus L.Mnium hornum Hedw.Phalaris arundinacea L.Ranunculus penicillatus subsppenicillatus(Syme)S.D.WebsterVaucheria sp

CommonnameMarshmarigold

Yellowflagiris

ReedcanarygrassWatercrowfoot

Presence Reach 1 Reach 2 Reach 3

EcologicalSurveyof RiverTeignat CastleDrogo,Devon.28/08/1997 16

The number of species recorded in each reach were similar (9-11), although reach onehad slightly fewer bryophyte species than the other reaches. The total percentage coverfor each 20 metre section was lowest in reach one and similar in the other two reaches.The most significant factor influencing the species present at reach one was the lessshaded nature of the river compared to the downstream reaches. Ranunculuspenicillatus subspecies penicillatus and Callitriche hamulata were noticeably moreabundant than in the downstream sections and the only occurrence of Myriophyllumalterniflorurn was in reach one.

There were no significant differences in species or abundance of macrophytes betweenreaches two and three.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 17

4. Assessment of historic impacts of the hydroelectric scheme.The smaller of the two turbines ceased operation in 1993 and so it would be reasonableto expect any significant impacts of the abstraction regime to still be apparent,although the channel is likely to have recovered from any minor impacts.

There is no obvious evidence from our ecological surveys of any major impacts as aresult of the historical abstraction of water from reach 2. The macrophyte andinvertebrate samples are very similar in each of the three reaches surveyed and thephysical habitats show no significant signs of degradation.

In particular the presence of similar bryophyte populations in reaches 2 and 3 suggeststhere has been no major impact of abstraction. If the historical abstraction hadsignificantly stabilised the flows or reduced water levels it is probable that this surveywould have recorded more terrestrial mosses on the exposed rocks and boulders. Thepresence of several species of aquatic mosses and liverworts on submerged andperiodically inundated surfaces therefore indicates a negligible impact in the recentoperation of the turbines.

The remnant channels on the mature island may have become more silted and blockeddue to lower flows when the turbines were running but some similar habitats wereobserved both upstream and downstream of the central reach. The abstraction of wateris therefore unlikely to be the principle cause of the siltation of these channels.

Although fewer invertebrates (number of families, species and individuals) weresampled in reach two this was considered to be more likely to be due to sample errorthan to ecological differences. The invertebrate population of the river is likely torecover relatively quickly from the impacts of abstraction through downstream driftfrom the unimpacted reach and so minor effects would not be detected.

The biological survey conducted by the National Trust (1990) noted the presence ofthe nationally rare aquatic moss Rhynchostegiurnlusitanicum on rocks in the river nearLogan Stone. This is within reach two but did not coincide with our macrophytesurvey site and so the absence of records from our survey does not indicate its absencefrom the river.

The number of riffles, extent of flow types (cascade to glide), extent of tree featuresand extent of channel features (islands, exposed boulders, side bars etc.) recorded forRHS were similar in reaches two and three. The lower flows during the sixty years ofabstraction did not result in any observable change in physical habitats within thereaches.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 18

5. Assessment of impact of proposed abstraction regimes.The effect of abstracting a volume of water from reach two will be to reduce both theactual water level in the river and to reduce the variability of flow volume. The impactscan therefore be categorised as those resulting from lower than normal flows and thosedue to more constant flow rates.

The average flow in the river is 3.5 ITI3S-1with a range of 0.2 to 50.1 m3s-'. Incomparison the turbine has a capacity of 1.3 m3s4. The turbine will therefore haverelatively little effect on water level during periods of higher flow (particularly winter)but quite a significant impact during low flow conditions in the summer months.

Two abstraction regimes are being considered for the river;Removal of 50% of water above Q95 level with a prescribed minimum of 0.6 m3s-'Removal of 75% of water above Q95 level with a prescribed minimum of 0.8 m3s-'

5.1 Potential effects of alteration of the variability of flows.

By reducing the variability of flows in the river the abstraction regime will potentiallyhave effects on several aspects of the river ecology. Firstly, many plants, particularlymosses and liverworts, grow abundantly on rocks and other substrates which areperiodically submerged. If the peak flows are reduced then some of these species maysuffer a reduction in available habitat.

The second effect may be to increase siltation. With lower flows the river will have lessenergy to transport sediments and to erode deposits and so a general increase in siltlevels could occur. There is some evidence that this has happened in the past on a smallscale (section 4.). Increased siltation would particularly affect the invertebrates whichrequire fast flow over boulders and cobbles as there may be a reduction in the qualityof these habitats. Any impact on the invertebrate population could also affect the fishand dippers which feed on them.

A reduction in flood water levels could cause drying out of some adjacent habitatsalthough there are few at risk (one small pond and some side channels) as thesehabitats may not be inundated as regularly as normal.

Having assessed the flow data provided and the models of abstraction it seems likelythat the affects on flow variability will be minimal and hence unlikely to affect theecology of reach 2.

5.2 Potential impacts of reduction in flow levels.

Abstracting water from the Teign will reduce the levels of water in reach 2. This couldcause recession of the river bed (drying out and colonisation by terrestrial plants) andimpact hydraulically linked habitats.

Recession of the river bed would reduce the available habitat for both invertebrates andmacrophytes and could consequently have an impact on bird, mammal and fish lifeusing the river. Baxter (1961) states that recession begins to occur at flows of 1/8 to

Ecological Survey of River Teign at Castle Drogo, Devon.01/09/1997 19

1/2 of average daily flow depending on the size of the river. This is equivalent to aflow of approximately 0.45 - 1.8 m's-I in the Teign.

A lowering of the water level could lead to drying out in hydraulically linked habitats.This would include the standing water on both banks and some parts of the remnantchannels as well as the small spring at the bottom of the reach (Figure lb) and the alderpopulation.

A further impact of lower water levels could be to impair fish migration through thereach. Salmon migrate in the Teign from May to November and require sufficientflows to negotiate the reach During the summer months salmon tend to migrate fromestuaries on the decreasing part of the hydrograph after flood events and will travelupstream on the higher flow or subsequent flood events. The fish will then remain in asuitable habitat within the river until moving to spawning grounds towards the end ofsummer. The abstraction regime should, where possible, maintain a minimum flow inthe river sufficient for salmon migration and minimise the reductions in spate flowdischarges to facilitate migration through the reach.

An additional factor affecting the salmon migration is the discharge from the turbinehouse. Salmon generally follow the parts of the river with most flow and so the turbineshould ideally not discharge a greater volume of water than the residual flow.However, at periods of spate flows when migration is most likely to occur, the turbinedischarge will generally be less than the volume of water remaining in the river.Therefore there will only occasionally be any potential impact on salmon migrationfrom the turbine discharge.

5.3 Preferred abstraction regime.

The ecological surveys of the river did not record any particularly notable plant orinvertebrate species or any extensive areas of adjacent habitats likely to be impacted byabstraction. A previous survey did record a nationally rare aquatic moss,Rhynchostegium lusitanicum, (National Trust, 1990) but this was recorded during theprevious period of abstraction and there is no reason to suspect that renewedabstraction would have any affect on its population.

There is little difference between the two abstraction regimes in terms of reducedvariability of discharge. Both reduce the average summer flows to the prescribedminimum and peak flows at other times are only reduced by a minor amount. The mostimportant criteria is therefore maintenance of an ecologically acceptable minimum flowrate, particularly regarding the migration of salmon during the summer. The preferredscheme is therefore abstraction of 75 percent of the flow with a prescribed minimum of0.8 m3s-'. There is a small risk with this regime that salmon will occasionally attempt toswim up the turbine outfall but maintaining a greater prescribed minimum level isconsidered a more critical factor.

Ecological Survey of River Teign at Castle Drogo, Devon.01/09/1997 20

6. Conclusions and recommendations.The river Teign at Castle Drogo is a high quality habitat with two of the surveyedreaches being of nationally outstanding quality. The invertebrate fauna is fairly diversealthough no particularly notable species were recorded in the samples. Similarly themacrophyte surveys did not record any rare or unusual species although a nationallyrare moss species has been recorded during a previous study.

River Corridor Surveys for the three reaches did not indicate any habitats likely to beimpacted by abstraction as the steep valley and hard geology prevents the formation offens, marshes and other wetland habitats.

There was no evidence for detrimental historical impact of the abstraction on reach 2and hence no reason to suspect that renewed abstraction would have a detrimentaleffect. The most important criteria is to maintain a sufficient flow in the river toprevent recession of the river bed, i.e. drying and invasion of terrestrial flora. Thenatural variability of daily flows is extremely high (0.2-50.1 m3s4) and the turbineabstraction has a minor effect for much of the year. During the period when abstractiondoes reduce flow variability maintaining the minimum flow volume is a more importantcriteria.

Our preferred abstraction regime is removal of 75 percent of the flow above Q95 witha prescribed flow of 0.8 m3s-'.

Following initiation of the abstraction we recommend that the National Trust consider,for a minimum of three years, regular annual monitoring of the impacted reach duringthe summer period. This would allow any changes in macrophyte or invertebratepopulations to be detected, and in particular impacts on the population ofRhynchostegium lusitanium.

At the point of discharge from the turbine house further monitoring of habitats andinvertebrates, particularly in the initial period of operation, should be considered toidentify any potential impacts in the immediate vicinity, such as scoring of the river bedor erosion of the opposite bank.

Ecological Survey of River Teign at Castle Drogo, Devon.01/09/1997 21

7. References

Baxter, G. (1961) River utilisation and the preservation of M gratory Fish Life. ProcInstn Civ Engs. 18:225-44

EA, (1996) River Habitat Survey Newsletter. 3:4

EA, (1997a) River Habitat Survey Field Survey Guidance Manual

EA, (1997b) River Habitat Survey Newsletter. 5:3-4

EA, (1997c) River Habitat Survey Newsletter. 4:3

National Trust, (1990) Biological Survey, Castle Drogo, Devon. National Trust,Cirencester

NRA, 1992, River Corridor Surveys - Methods and Procedures. ConservationTechnical Handbook No. 1.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 22

Appendix I.

Summary data for River Corridor Surveys.

Reach 1. Upstream of weir.

Conditions durin surve : Dry and overcast Rain during previous 72 hours butflows relatively low.

Ph sical Features:Left Bank: Predominately boulders, more earth in 100m immediately upstream of

weir. Bank structure is often complex due to boulders and cattle impact. Someold reinforcements apparent.

Right Bank: Similar to left bank although there are some remnant channel featuresjust upstream of the footbridge - damp conditions and some open water.

Vegetation:Left Bank: Short grass with bracken and other herbs near/on bank top. More diverse

on bank face with ferns and Oenanthe crocata particularly abundant andmosses and liverworts on boulders.

Right Bank: Similar to left bank but restricted access to wooded section has meanttaller understorey dominated by Luzula species and ferns.

Channel: Mosses and liverworts abundant, mainly on boulders and cobbles. SomeCallitriche hamulata and Ranunculus penicillatus subspecies penicillatus fairlycommon and Oenanthe crocata is the dominant emergent macrophyte.

Landuse:Left Bank: Semi-improved grassland adjacent to upstream 300m, broad leaved

woodland for rest.Right Bank: Similar to left bank.

Recreation:The area is popular with walkers, there is a footpath along the valley and othersthrough the Castle Drogo estate.

Other:Dippers, grey wagtail, damselflies and dragon flies and salmon all observed.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 23

Appendix I.

Reach 2. From weir to turbine house.

Conditions durin surve : Dry and overcast. Rain during previous 72 hours butflows relatively low.

Ph sical Features:Left Bank: Boulders predominate, particularly upstream of the islands. There is a

narrow fisherman's path along the upper 100 metres which is regularlyinundated by higher flows (woody debris accumulations frequent on path). Onesmall pond is present towards the downstream end of the reach (unvegetated).

Right Bank: Boulders predominate. Several remnant channels and a side channelaround largest island.

Vegetation: Left Bank: Densely wooded (broad-leaved) for most part. Alnus glutinosa, Fraxinus

excelsior, Fagus sylvatica and Salix species common in bank. Luzula species,Oenanthe crocata most common, with mosses and liverworts on boulders.

Right Bank: Denser tree canopy than left bank, more Luzula sp., less 0. crocataChannel: Mosses and liverworts on all boulders and in splash zone. Some Oenanthe

crocata, particularly in margins but few submerged higher plants noted.

Landuse: Left Bank: Broad leaved woodland.Right Bank: Similar to left bank. Turbine house and pipe also present.

Recreation: The area is popular with walkers, there is a footpath along the valley and othersthrough the Castle Drogo estate.

Other:Dippers and grey wagtail observed. Salmon seen in fish ladder.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 24

Appendix 1.

Reach 3. Downstream of the turbine house.

Conditions durin surve : Dry and overcast. Rain during previous 72 hours butflows relatively low.

Ph sical Features:Left Bank: Lower section is a boulder strewn bank appearing to be part of the water

course during higher flows. Now partly colonised by trees and othervegetation. An old channel is apparent and there are many sandy deposits alongthe bank. The upstream section is earth and boulders with occasional smallsandy deposits.

Right Bank: Similar to reach 2- boulders predominate Bank height c0.6m.

Vegetation:Left Bank: Densely wooded (broad-leaved) for most part. Alnus glutinosa, Fraxinus

excelsior, Fagus sylvatica and Salix species common in bank. Luzula species,Oenanthe crocata most common, with mosses and liverworts on boulders.

Right Bank: Similar to left bank. Some areas of very dense shading of channel fromoverhanging trees.

Channel: Mosses and liverworts on all boulders and in splash zone. OccasionalOenanthe crocata and some patches of Callitriche hamulata and Ranunculuspenicillatus subspecies penicillatus.

Landuse:Left Bank: Broad leaved woodland.Right Bank: Broad leaved woodland.

Recreation:The area is popular with walkers, there is a footpath along the valley and othersthrough the Castle Drogo estate.

Other:Dippers and grey wagtail observed. Islands and more diverse habitats thanupstream sections. Lots of woody debris.

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 25

Appendix 2.

Full species list for invertebrate samples

Number of individuals in sample

Famil S ecies Reach 1 Reach 2 Reach 3Planariidae Polycelis felina

3Hydrobiidae Potamopyrgus jenkins 448 12 48Lymnaeidae Lymnaea peregra 6

4Ancylidae Ancylus fluviatilis 5 24 16Sphaeriidae Pisidium spp. 32

7Oligochaeta Oligochaeta 48 80 168Glossiphoniidae Glossiphonia complanata 3

1Helobdella stagnalis 1

Hydracarina Hydracarina 16 8 8Gammaridae Gammarus pulex 3

Baetidae Baetis rhodani 56 136 184Heptageniidae Ecdyonurus sp.

1Ephemerellidae Ephemerella ignita 440 976 1088Ephemeridae Ephemerella dancia 1

Leuctridae Leuctra fusca 1

Chloroperlidae Chloroperla torrentium 6

Agriidae Calyopteryx virgo 1

Cordulegasteridae Cordulegaster boltoni

1Veliidae Velia caprai

Corixidae Sigara venusta

Pleidae Plea leachi

Dytiscidae Platambus maculatus 3

Hydrophilidae Hydraena gracilis 40 1 2Elminthidae Limnius volkmari 72 32 16

Elmis aenea 16 4 9Esolus parallelepipedus 1

1Rhyacophilidae Rhyacophila dorsalis 9 32 40

Rhyacophila munda

2 4Agapetus sp

1

Glossosoma sp

1Philopotamidae Philopotamus rnontanus

1Hydropsychidae Hydropsyche siltalai 8 64 24Limnephilidae Chaetopteryx villosa 1 2 1

Halesus digitatus 2

5Potamophylax latipennis 5

3Odontoceridae Odontocerum albicarne

1 1Leptoceridae Oecetis testacea 72 2 4

Mystacides agunea 8

2Goeridae Silo pallipes

1

Lepidostomatidae Lepidostoma hirtum 56 16 24Brachycentridae Brachycentrus subnubilis 32 24 56Sericostomatidae Sericostoma personatum 24 16 2Tipulidae Dicranota sp 32 8 24

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 26

Appendix 2.

Tipula sp. 2

1Ceratopogonidae Indent 16

-Chironomidae Chironomidae 256 184 440Simuliidae Simulium reptans 104 24 24

Simulium ornatum 32 8 24

Simulium argyreatum 80 16 80

Simulium aureum 8 - -

Simulium venzum 8 - 1Empididae Hemeradromia gp

10

Rhagionidae Atherix marginata 5 8

Atherix ibis 1 8 1

Total No. of families 42 28 38

Total No of s ecies 43 29 39

Total No of individuals 1962 1701 2321

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 27

Appendix 3.

River Habitat Survey forms

Ecological Survey of River Teign at Castle Drogo, Devon.28/08/1997 28

1997 RIVER HABITAT SURVEY Page 1 of 4

Altitude (m)Solid geology codeDistance from source (krn)Height of source (m)

Slope (m/km)Drift geology codeSignificant tributary ?Water Quality Class

Flow category (1 - 10)Planform categoryNavigation ?

MM•

Site Number : () Mid-site Grid Reference : River E I NDate 11 / 6 /1997 Time 1;1.Sb Surveyor name Pj2tOxlit

VFSSAccredited Surveyor ? No Yes 1:21/ If yes,state code

Adverse conditions affecting survey ? No vs Yes 0 If yes,state

Bed of river visible ? No D partially X entirely 0 (tick onebox).

Yes 1ZrDuplicate photographs : general character ? No D (tick onebox)

Site surveyed from : left bank X right bank 0 channel Z (tick as appropriate)

SERCONsurvey in addition? No 0 Yes 21 (tick one box)

I I I

shallow vee 121concave/bowl (If U-shapedglacial valley-add "U°)

deep vee

gorge

N6.Ce0WiEr kt Terraced valley floor ?

: • I•

Riffles 0

symmetrical floodplain

FL/asymmetrical floodplain

UCt

I • •

Unvegetated point bars

estYes El

Pools Vegetated point bars

1997 RIV HABITAT SURVEY : TEN SPOT-CHECKS Page 2 of 4Spot-check 1 isat : upstream end downstream end 0 of site (tick one box)

• • ; • I; • • • •

one entry only 1 2 3 4 5 6 7 8 9 10

Material fie Ain ma. rAft a. cc sewa arcat e Igoe ER E E B o eoBank modification(s) NXNo,Rs,R4pcm, fo,f, WoE E No U eND oBank feature(s) NI;NO,K. SCft, vP,setvs 0 DSO No 05€

Channel substrate ' Nv.sEfro Co,a; 3.4sitet. km 0 co ea CO o CO CO c0 et) V fkFlow type ' Fr,Ot ew.uv4a. M UP,SAl,/44no uw enInv ? m R smsmChannel modification(s) etc leo,cy n, RI,DA,FO 0 0 Nb 0 0 0 Nb (40 es0 mmn0

CD•-•4.1 fpfl• nChannel feature(s) Nv,No,MAIL VS,Aft M

VI o No N NO 0 Ro NoRo RoRo Z n, r

5'wzv =....DMaterial 1 tam. so,at Gs. cc sewe.44ata4ow EABo E E Efi t3oBoEA *:grBank modification(s) f41(NO,Ilf„et econ OMDA NoNo ONo b 0 0 NoNo No

=:..,.Bank feature(s) NY,NO,K. SC Pt VTsa.n 140 No b ND 0 No No o No Nb

•.• I.

P 30

11• o • • • 1 • * 0

n n cLand use: chooseone from Bl, a, OR,kW, SC,TN, RP,IC, TI, WL, OW, SU, RS 3.z

toLAND USEWITHIN Sm OF LEFTBANICTOPi GL St_ 5-

LEFTBANKTOP(structure within I rn MEW) I) SU S S SS.SS 5I

gLIFT BANKFACE(stnicture) wun/cC 5 $ $ S 5 S 5 $ 5 7roaRiCHT BANK FACE (structure) ditrisric cc_555c55sscr,C.RICHTBANKTOP(structure within In)) erWsicUUU UUU U s s 5

LAI4D USEWITHIN Sm OF RIGHTBANKTOP81_ BL BL

NONE

Liverworts/mosses/lichens

Emergent broad-leaved herbs

Emergent reeds/sedges/rushes

Floating-leaved (rooted)

Free-floating

Amphibious

Submerged broad-leaved

Submerged linear-leaved

Submerged fine-leaved

Filamentous algae

•

e //

• t •

Use end "catch•cdr column for types not occurring In spot checks as well as overall assessment over SOOm (use f or

'

SITENO. 1997 RIVER HABITAT SURVEY : 500m SWEEP-UP Page 3 of 4

Broadleaf/mixed woodland (BL)

Coniferous plantation (CP)

Orchard (OR)

Moorland/h eath (MH)

Scrub (SC)

Tall herbs /rank vegetation (TH)

Rough pasture (RP)

Improved/semi-improved grass (/G)

Tilled land (TL)

Wetland (eg bog, marsh, fen) (WL)

Open water (OW)

Suburban/urban development (SU)

Rock and scree (RS)

E E

Natural/unmodified

Vertical/undercut

Vertical + toe

Steep (>45')

Gentle

Composite

Artificial/modified

Resectioned

Reinforced - whole bank

Reinforced - top only

Reinforced - toe only

71- .

Artificial two-stage

Peached

Embanked

Set-back embankments

• I • I •

TREES (tkk oneboxper bank)

Left

None LIIsolated/scattered 0Regularly spaced, single LIOccasional clumps 0

Semi-continuous LIContinuous

ASSOCIATEDFEATURES (tick one boxper feature)

Shading of channel

Overhanging boughs

Exposed bankside roots

Underwater tree roots

Fallen trees

Coarse woody debris

None Present E (>33%)

0 LIMe.0

•None Present E(>33%)

Waterfall(s) Le 0 0

Cascade(s) ID gf 0Rapid(s) LI 211 0Riffle(s) 0 121. CIRun(s) 0 CZ 0Boil(s) Le 0 0Glide(s) 0 0 JZPool(s) Zr 0 0Ponded Reach(es) 111 vr ID

Present

0

LILILILI0LI LI

E(>33%)

Marginal deadwater

Exposed bedrock

Exposed boulders

Unvegetated mid-channel bar(s)

Vegetated mid-channel bar(s)

Mature island(s)

Unvegetated side bar(s)

Vegetated side bar(s)

Discrete silt deposit(s)

Discrete sand deposit(s)

1997 RIVER HABITAT SURVEY: DIMENSIONS AND INFLUENCES Page 4 of 4

I -I I • "I #1 I I "II f

LEFTBANK CHANNEL

Banktop height (m) .20 Bankfull width (m)

Is banktop height also bankfullWater width (m)height? (Y or N) 21

Embanked height (in) Water depth (m)

If trashline is lower than banktop break in slope, indicate: height above water (m).Bed material at site is: consolidated (compact) 0 unconsolidated (loose)

riffle run or glide

I II, II V If

Location of measurement is: El

unknown Elother El

13RIGHT BANK

Banktop height (m)

Is banktop height also bankfullheight? (Y or N)

Embanked height (n)

None _ Major Intermediate Minor Major Intermediate MinorEl Weirs RevetmentsSluices OutfallsCulverts ,-, FordsBridges

Deflectors

Other (state)Is water impounded by weir/dam? No 0 Yes, <33% of site >33% of site El

••I, III, • Of •

None -

Dredging El

Enhancement El

• •

Mowing El

Other (state)

a

Weed-cutting El

None /

Waterfalls > 5m high 0 Artificiai open water 0 Bog 0 Fringing reed-bankBraided/side channels 0 Natural open water CI Carr 0 Floating matDebris dams 0 Water meadow 0 Marsh 0 Other (state) Leafy debris 0 Fen 0 . Flush 0

' SI

Is 33% or more of the channel choked with vegetation? No / Yes 0

I I . : - a

None D Giant Hogweed 0 Himalayan Balsam Japanese Knotweed 0 Other (state).r. ... ..F?....A

4 • I 'Issas II 01111 ' I

Malor Impacts: landfill - tipping - litter - sewage - pollution - drought - abstraction - mill - dam - road - rail - industry- housing - mining - quarrying - overdeepening - afforestation - fisheries management - siltingLandManagement: set-aside - buffer strip - headland - abandoned land - parkland - MoD

Animals: otter - mink - water yole - kingfisher -dipper -grenwagtail -sand mprtin - heron ra onflies/damselflies

Altaka ipts60 ,_(\p-1(6-41-z jts4Other significant observatlons:Q.A.„k Cask30,4.Ar..kre

I II

Ei

ID

Alders? None El Present 0 Extensive Diseased Alders? None Present 0 Extensive El

A I I II•

SC2 5C3 5C4 SC5 5C6 SC7

o o 0 0 b c>0 0 0 0 co

0 0 6 0050 0 co 5

100 I 60

0 0 0

0 0 0 5

35, 45, 55, 65, 75, 85, 95.

SC8 5C9 SC10 T% Planform re-ali ned% Ion -or cross-section modified% recove from I/II% recove of bank from en ineerin

% of ri arian zoneve etation natural 0% of V with affini to rivers 0%of bank ve etation with 'aliens' 0

VIII: % of bank with ye etation 'natural 10c>IX: % of VIII with affini to rivers 5

U. IMPACTS

1 Acidification2 Toxic/Industrial/A ricultural effluent3 Sewa e effluent4 Groundwater abstraction5 Surface water abstraction6 Inter-river transfers7 Channelization8 Mana ement for flood defence9 Man-made strudures10 Recreational ressures11 Introduced s ecies

V. SFs/AFIs

a Plant/animal observationsb Waterfalls>5m hi h

I c Gor esd Flood lain wetlands - recreatablee Flood lain wetlands - unrecreatablef Notable islands

Native inewoodsh Wide/s ecial ri arian zones

Ne ative - litterNe ative - diseased alder

k Others

o 0 0 0 00 0 0 0 00 6 0 Cs 0 0co to. too l oom too too ko tto 040 bo

45 45 4 5 4 5 5 45 4 5 S

Notes

Agra 04e

uk: L.41-4,43

kkrzte. "tg atsra Lit race-a( o-a .114

ICutraC t_ • uareith suiLticipltre-t3•6

?a_ Po •V; N0kkc skreu

Notes

, 4.2L1 br;scin

tc era c, 10k Lkemkbe,61. Lisa NAaa nAiNt4-s.

Tobe completed only for SERCONpurposes stte,(3)SERCON SWEEP-UP - ITEMS I-1X List in 'T' the % to nearest number: 0, 1, 5, 15, 25,

I i

W. NOTES ak., Yts.c.a_Q, S

11Hs& LvA.AAA.Q. c),,v re4,

116r, k, Lnxim beak 4.-A. Lchz,v,DL 0 s J44 6\, )4,4, real (me kia-44-

uaek-r-, ara, I`A.0-rok14 0\ kW, -32-cY-tAi-n iebst.)?-4nr-

6L

1997 RIVER HABITAT SURVEY Page 1 of 4

•

Altitude (m) Slope (m/km) Flow category (1 - 10)

Solid geology code Drift geology code Planform category

Distance from source (km) Significant tributary ? Navigation ?

Height of source (m) Water Quality Class

Site Number :- T alyN) a Mid-site Grid Reference : River :-TE

Date a./..6/1997 lime 5 Surveyor name sccubk-

Accredited Surveyor ? No Yes 1/ If yes,state code PF SS

Adverse conditions affecting survey ? No Er Yes El If yes,state

Bed of river visible ? No CI partially Li entirely (tick onebox)

Duplicate photographs : general character ? No El Yes Vie (tick onebox)

Site surveyed from : left bank 0 right bank l: channel c21/ (tick as appropriate)

SERCONsurvey in addition? No 0 Yes Zi (tick one box)

• • • ' • • I • I I

D shallow vee Li concave/bowl(If U-shapedgladal valley -add 1U1)

JZI deep vee CI symmetrical floodplain

C7 gorge El asymmetrical floodplain

No gi Yes CITerraced valley floor ?

: • • Si II

Riffles I b Unvegetated point bars

Pools Vegetated point bars

1997 RIVER HABITAT SURVEY : TEN SPOT-CHECKS Page 2 of 4Spot-check 1 isat : upstream end downstream end 0 of site (tick onebox)

•

= one entry only 1 2 3 4 5 6 7 8 9 10

•Material 1 mor.so,ccscs.um. a. cc sr,wtcAs4 nv e E EA Ee aEBank modification(s) f/c.NO,RS,ru,Pc06,est ar 0boo0NDtiooN0Bank feature(s) WV,NO,EC,SCPa.vP,SitP5 o D ND b 0 ND b NONOChannel substrate NI! 84,so, co, a; st st cL go 13 co co co Co CO g0 CC) Snow type 16 at SW.UK CF, UP,sM,NP,NO UP ewsin s 5 OWs RChannel modification(s) rs, tm, a; as,its,o4 A° 0 NO o No No NO o NO1 zen

Channel feature(s) tiv: No, Et Ant lit w nt0 b Ro

Ro Ro Ro 1 D D-,5..,v=Material I NP.M.00.Co.GS.SAPC(3.cr.gwtatittlawSo go 14; E EC EA go Ei *.c,*g.z- ,...

Bank modification(s) tit. Ho, as,RI,PC01),SM,Da o N o No f4o 0 ND 0 0 il w « fir

Bank feature(s) NY,NO,EC,SCPP.VPRsn bNlb 0 0 58 0 No b b b F.=P.

I • I • I • Is - • - or•• I 0

n n C

Land use : chooseone from BL,CP,OR,MH, SC,TH,RP,1G,11„WI, OW, SU,RSn.-,n

toLAND USEWITHIN 5rn OF LEFTBANKTOP 81- L.81-a-8 131-si- el- a. sL 54LEFTBANKTOP(sUucturewithin 1m) olu/s/c 5 5 S c S 55 5 5 s 67,LEFTBANKFACE(structure) It/WS/C 5 5 5 s S SSS 5 S v-a.RIGHTBANK MCE (structure) IN/Iiit 5 5 6 5 5 c, 6 GS s aRIGHTBANKTOP(structurewithin lin) Milsic S 5 S ,5 -5 5 S S C 5

F.LAt4C1USEWITHIN Sm OF RIGHTBANKTOP i31— el-% 91_St_Si_ eta BLEt. gi..

I• • $4 0

00 •NONE

Liverworts/mosses/lichens

Emergent broad-leaved herbs

Emergent reeds/sedges/rushes

Floating-leaved (rooted)

Free-floating

Amphibious

Submerged broad-leaved

Submerged Iinear-leaved

Submerged fine-leaved

Filamentous algae

Useend ''cotch-alP column for types not occurring M spot checksas well os overall assessmentover SOOm(use E or vot )t

stre'Nb. 1997 RIVER HABITAT SURVEY : 500m SWEEP-UP Page 3 of 4

IP •I I•

Broadleaf/mixed woodland (BL)

Coniferous plantation (CP)

Orchard (OR)

Moorland/heath (MH)

Scrub (SC)

Tall herbs /rank vegetation (TH)

Rough pasture (RP)

Improved/semi-improved grass (IG)

Tilled land (TL)

Wetland (eg bog, marsh, fen) (WL)

Open water (OW)

Suburban/urban development (SU)

Rock and scree (RS)

: •

Natural/unmodified

Vertical/undercut

Vertical + toe

Steep (>45')

Gentle

Composite

Artificial/modified

Resectioned

Reinforced - whole bank

Reinforced - top only

Reinforced - toe only _

Artificial two-stage

Pcached Th..1/2"...v0Atv

Embanked

Set-back embankments

I •

TREES (tick oneboxper bank)

Left

None LI

I

Right

0

ASSOCIATEDFEATURES

Shading of channel

(tick onebox per feature)

None Present E (>33%)

Isolated/scattered 0 LI Overhanging boughs •

ErRegularly spaced, single LII 0 Exposed bankside roots 12". 0 0Occasional clumps

Underwater tree roots

Semi-continuous El 0 Fallen trees 2" 0 0Continuous

Zi Coarse woody debris LI 121. 0

Waterfall(s)

Nig Present E(>33%)

0 0 Marginal deadwater

None

0

Present

ErE(>33%)

El •Cascade(s) 0 Pi 0 Exposed bedrock El 21' 0Rapid(s) LI 121" 0 Exposed boulders 0 0 /Riffle(s) 0 kr 0 Unvegetated mid-channel bar(s) gr 0 0Run(s) LI kf LI Vegetated mid-channel bar(s) W 0 0

Boil(s) 0 kr LI Mature island(s) 0 D 0Glide(s) LI kr 0 Unvegetated side bar(s) El gr ElPool(s) V 0 0 Vegetatedside bar(s) gle 0 ElPonded Reach(es) [2' 0 0 Discretesilt deposit(s) 7 0 El

Discretesand deposit(s) 0 01 0

1997 RIVER HABITAT SURVEY: DIMENSIONS AND INFLUENCES Page 4 of 4

I I' •• •0 I "I I II

• 2.—

g.s0:

LEFTBANK

Banktop height (m)

Is banktop height also bankfullheight? (Y or N)

Embankedheight (rn)

CHANN EL

Bankfull width (m)

Water width (m)

Water depth (m)

RIGHT BANK

Banktop height (m)

Is banktop height also bankfullheight? (Y or N)

Embankedheight (m)If trashline is lower than banktop break in slope, indicate: height above water (m) =Bed material at site is: consolidated (compact) unconsolidated (loose)

Location of measurement is riffle run or glide

El unknown ElEl other El

I I. I fat IS I 0#

Major Intermediate Minor Major Intermediate MinorNone

CI Weirs

Sluices

Culverts

Bridges

I Is water impounded by weir/dam? No

1 S•

Revetments

Outfalls

Fords

Deflectors

Other (state)

Yes, <33% of site El >33% of site

on II f I • It •

CI ( Fisar

None ajZi Dredging CIEnhancement 0

Mowing El Weed-cutting 111Other (state)

None

Waterfalls > 5m high

Braided/side channels

Debris dams

Leafy debris

Artificial open water

Natural open water

Water meadow

Fen

IS •

Bog ElCarr ElMarsh ElFlush El

Fringing reed-bank CIFloating mat 0

Other (state).C4Thita6A.

t

Is 33% or more of the channel choked with vegetation?

I

None fl Giant Hogweed El Himalayan Balsam

No Yes El

Japanese Knotweed gr Other (state).r. . 0A

Of I 'SI tIll ' I " I

Major Impacts:

LandManagement:

landfill - tipping - litter - sewage - pollution - drought - abstraction - mill - dam - road - rail - industry- housing - mining - quarrying - overdeepening - afforestation - fisheries management - silting

set-aside - buffer strip - headland - abandoned land - parkland - MoD

Animals: otter - mink - water yole - kin fisherDLe_Other significant observations:

- grey wagtail - sand martin - heron0, fiell

dra onflies/damselfli

Os-o.fioa

•.7„

Alders? None El Present El Extensive Diseased Alders? None Present n Extensive [1]

A

'

35, 45, 55, 65, 75, 85, 95.

5C8 SC9 SC10

C 5

% Planform re-ali ned% Ion -or cross-section modified% recove from I/II96 recove of bank from en ineerin96 of ri arian zone ve etation natural96 of V with affini to rivers96 of bank ve etation with 'aliens'46 of bank with ve etation 'natural'

96 of VIII with affini to rivers

U. IMPACTS

1 Acidification2 Toxic/Industrial/A ricultural effluent3 Sewa e effluent4 Groundwater abstraction5 Surface water abstraction6 Inter-river transfers7 Channelization8 Mana ement for flood defence9 Man-made structures10 Recreational ressures11 Introduced s ecies

SC1 SC2 5C3 SC4 SC5

o 0 0 C c,

ot.o 0 b

Do oo tee oob o o 0 o0 o o

I/00 100 5 too 00145 5 4 4 5

5C6 5C7

IS a

0 0 0 b

00 00 0 '000 0 D t30 0

o 5Do q5. Vt0

5 5 $ 5 5 5

Tobe completed only for SERCONpurposes ciLe.T. SERCONSWEEP-UP- ITEMS I-IX List in T the 96 to nearest number: 0, 1, 5, 15, 25,

Notes

-

DL,ik_,cA_t. kt...519.8 oa 9#"-(3- tr466 oks-s3 kv-IL Ltv\z,PcNtukkr.tAikk L.4)e-era,INta Ak• 'AP4-ke4•Ck 0-4%

kW- rikkc-

V. SFs/AFIs

a Plant/animal observationsb Waterfalls>Sm hi hc Gor esd Flood lain wetlands - recreatablee Flood lain wetlands - unrecreatable

I f Notable islandsNative inewoods

h Wide/s eclal ri arian zonesNe ative - litterNe ative - diseased alder

k Others

Notes

kt e..rs(1 trei

Lona N-4L-Q- 044.

elkk meickurt uAlk (t\oN trisLi ,ckk,. vga& 4e26q.

sss=I i

W. NOTES D r4ssco Daoitei

o-Liccroo 3vib-e Nw-clA NteRgcsa oLcia tfrastd3Ve we-Zr `LS crk, Lisa NAlk UES -9-A4k &k,tha uit;IN taal JCL 14 11/401-13u-.01/4-zt.la

fibtralij e-04A koj kins 114a, -u ttevic,;auxin. kt,Aar2., 6s4aL Jsi (44

(a Li :id ,...ourgi2 arac.ft-J/w3- thekck

á

1997 RIVER HABITAT SURVEY Page 1 of 4

I : /

Altitude (m) Slope (m/km) flow category (1 - 10)Solid geology code Drift geology code Planform categoryDistance from source (km) Significant tributary ? Navigation ?Height of source (m) Water Quality Class

Site Number TrEOaNO Mid-site Grid Reference : River I

Date 12- 1 16 /1997 Time I : 2.O Surveyor name P ,fr-r.AvlarAccredited Surveyor ? No lip Yes Er II yes,state code ? F3S

If yes,state Adverse conditions affecting survey ? No Of Yes CI

Bed of river visible ? No 0 partially CI entirely Z. (tick onebox)

Duplicate photographs : general character ? No CI Yes 21 (tick one box)

Site surveyed from : left bank right bank 0 channel (tick as appropriate)

SERCONsurvey in addition? No 0 Yes Z (tick one box)

I I • I I

0 shallow vee

[21e deep vee

CI gorge

concave/bowl(If U-shapedglacial valley -add 'U')

symmetrical floodplain

asymmetrical floodplain

Terraced valley floor ? No Z Yes 0' I • p., 5 5

Riffles 2.0 Unvegetated point bars

Pools Vegetated point bars

1997 RIVER HABITAT SURVEY : TEN SPOT-CHECKS Page 2 of 4

Spot-check 1 isat : upstream end downstream end 0 of site (tick onebox)

= one entry only

Material 1 t4x so.co.ct Lama. cc sr,wtc4 a at aw

Bank modification(s) NICNO, •IS, PC(8),tod,caw

Bank feature(s) NxNO,IC SC,Pt VP,58, VS

1 2 3 4 5 6 7 8 9 10

* • •-•61 11

Bo E 1kBo to EA ENNo brJtNOK1O 0 0 0 6No o NON s? No o b JQ 0

80, CO, CP,SA,St a, PE,AR et, c

0 0

Channel substrate '

Flow type 1 FROf. SW,OW,a UP,SM,ND,NO

Channel modification(s) NK NO,at RS,014 FO

Channel feature(s) NyeNO,RO,ses,vs,Ay,nt

co co co 130go Sri\ sciNLABsfi1 RV

0 to 0 o NoNo NDNoNO 0

sR UWSfn

0 0 NO3„5'(1/41' o

Material 1 st at Baca cs.urt ct cc seweGAut rw

Bank modification(s) NK NO,RS,RI,met est DA

Bank feature(s) mgNO,EC.,SGPAVISS4 VS

: • • • •

LAND USEWITHIN Sm OF LEFTBANKTOP

LEFTBANKTOP (stmcture within 1m) R/U/S/C

LEFTBANK FACE(stnacture) =AK

RIGHTBANK FACE(structure) aNnic

RIGHTBANKTOP (structure within 1m) SAVSK

LAND USEWITHIN Sm OF RICHTBANKTOP

. I

• • I41-10

-AM

1345go E Bo z, a-t, No 0 NoNo No b 0 ND

NDNo No o oNo 0 No ON frO9.•

aa

C-

• • • • • •I •

Land use: chooseone from 81, cp, OR„PAH,SC,TH,RP,IC, TI,,Wks,OW, SU,RS

L Bi- EL L 181-RLSs ss,SC

s c_ s sccc-SSsSc ssssBL EL EL L eL.

•-

NONE

Liverworts/mosses/lichens

Emergent broad-leaved herbs

Emergent seeds/sedges/rushes

Floating-leaved (rooted)

Free-floating

Amphibious

Submerged broad-leaved

Submerged linear-leaved

Submerged fine-leaved

Filamentous algae

/ E 5 / E / E

Use end "catch.all• column for types not occurring In spot checks as well as overall assessment over SOOm (use E or .0"

SITE'Nb. 1997 RIVER HABITAT SURVEY : SOOm SWEEP-UP Page 3 of 4

• I I : • • •

Broadleaf/mixed woodland (BL)

Coniferous plantation (CP)

Orchard (OR)

Moorland/heath (MH)

Scrub (SC)Tall herbs /rank vegetation (TH)

Rough pasture (RP)

Improved/semi-improved grass(IG)

Tilled land (TL)

Wetland (eg bog, marsh, fen) (WL)

Open water (OW)

Suburban/urban development (SU)

Rockand scree (RS)

.E Enivvv:N.

Reinforced- top only 79-\ NNW

vwvv

Artificial/modified

Resectioned

Reinforced- whole bank

Reinforced- toe only

Artificial two-stage

Pcached

Embanked

Set-backembankments

Natural/unmodified

Vertical/undercut

Vertical + toe

Steep (>45)

Gentle

Composite

• I •

TREES (tick oneboxper bank)

•

ASSOCIATEDFEATURES (tick oneboxper feature)

Left Right

None Present E (>33%)None El CI Shading of channel CI CI 21Isolated/scattered El El Overhanging boughs • CI 0 ErRegularlyspaced,single El El Exposedbankside roots 21- CI 0Occasionalclumps El

Underwater tree roots 0 .1Zr 0Semi-continuous El El Fallentrees 21" 0 CIContinuous

Coarsewoody debris 0 21* CI

None Present E(>33%)

None Present E(33%)WaterfaII(s) re El El Marginal deadwater ID Er ElCascade(s) CI GO 0 Exposedbedrock o

oRapid(s) CI 23 CI Exposedboulders 0 CI

Riffle(s) 0 2' CI Unvegetated mid-channel bar(s) co' o ElRun(s) 0

0 Vegetatedmid-channel bar(s) IZr CI CIBoil(s) CI 2' 0 Mature island(s)

Glide(s) 0 Z CI Unvegetated side bar(s)

El El

Pool(s) 0. 0 0 Vegetated side bar(s) ca° CI 0Ponded Reach(es) le 0 Cl Discretesilt deposit(s)

Discrete sand deposit(s) 0

0

1997 RIVER HABITAT SURVEY: DIMENSIONS AND INFLUENCES Page 4 of 4j

III", •II "• V /I

LEFTBANK

Banktop height (m) I • 0Is banktop height also bankfullheight? (Y or N)

Embanked height (m) Water depth (m)

If trashline is lower than banktop break in slope, indicate:

Bed material at site is: consolidated (compact) Ill unconsolidated (loose) unknown E]Location of measurement is: riffle run or glide Li other Li

CHANNEL

Bankfull width (m)

Water width (m)11 .5

0.15height above water (m) =

RIGHT BANK

Banktop height (m)

Is banktop height also bankfullheight? (Y or N)

Embanked height (rn)

1. o

Major

Weirs

Sluices

Culverts

Bridges

Is water impounded by weir/dam?

Intermediate Minor

Revetments

Outfalls

Fords

Deflectors

Other (state)

No Yes, <33% of site Li >33% of site Li

Major Intermediate Minor

/III • Ie '

None Dredging Li Mowing ill Weed-cutting LiEnhancement (13 Other (state)

None

•

Waterfalls > Sm high Li Artificial open water 0 Bog Li Fringing reed-bank CIBraided/side channels Li Natural open water 0 Carr Li Floating mat 0Debris dams Li Water meadow Li Marsh Li Other (state).(4,Ctit1ttilLeafy debris Li Fen Li Flush D

•

Is 33% or more of the channel choked with vegetation? No Yes 0

I • :

None El Giant Hogweed Li Himalayan Balsam Japanese Knotweed 0 Other (state)

•'WOOS' If " I

Major impacts: landfill - tipping - litter - sewage - pollution - drought - abstraction - mill - dam - road - rail - industry- housing - mining - quarrying - overdeepening - afforestation - fisheries management - siltingLandManagement: set-aside - buffer strip - headland - abandoned land - parkland - MoD

Animals: otter - mink - water yole - kingfisher - dipper - rey wagtai

Other significant observations: 3vit. -La,b1,4

•

d martin - heron dragonflies/damselflies

(41) court04 co. 0-

Alders? None El Present n Extensive Diseased Alders? None Present ID Extensive 0

/ I I

Tobe completed only for SERCONpurposes ckt RDT. SERCONSWEEP-UP- ITEMSI-IX List in T' the % to nearest number: 0, 1, 5, 15, 25, 35, 45, 55, 65, 75, 85, 95.

SC1 SC2 5C3 SC4 SCS 5C6 SC7 SC8 5C9 SC10 TI: % Planform re-ali ned Ctz) 0 0 00 0 0 b

% Ion -or cross-section modified o 0% recove from% recove of bank from en ineerin

V:96 of ii arian zone ve etation natural LOb co (co toocr t too Ito zoo oo% of V with affini to rivers 0 0 (z> o 0 0 0 0% of bank ye etation with 'aliens' 5 0 o 0 0 0 0 0 5% of bank with ye etation 'natural' ck.S. o too too too too tee tO3 too too 95% of VIII with affini to rivers

I U. IMPACTS1 Acidification2 Toxic/Industrial/A ricultural effluent3 Sewa e effluentI4 Groundwater abstraction5 Surface water abstraction6 Inter-river transfers7 Channelization8 Mana ement for flood defence9 Man-made structures

I 10 Recreational ressures

pkt 1514k-kel

kirS, rota*,

4 3 45

Notes

0" ckan; di, c

11 Introduced s ecies

V. SFs/AFIsa Plant/animal observationsb Waterfalls>5m hi hc Gor esd Flood lain wetlands - recreatablee Flood lain wetlands - unrecreatablef Notable islands

Native inewoodsh Wide/s ecial ri arian zonesi Ne ative - litter

Ne ative - diseased alderk Others

N ot es

114-4-a

hity_ rare- 4,4

oQ rivazwe siuti,s9 (at 64 0,5-0A sipstA4144 .b.szi24k9

. NOT.ES".3.ye o_ficta A 11/.9_ s -1-ecktss (AL g-v-TakIctee_ct4Liz, 1,12 arts% ,Mk,st-L t•mrS8 U 3-431-Ak asc.Usz gektael

ininsusi 31\4. Nt030c %)curoi: 4, -s

Centre for Ecology & Hydrology

Institute of Freshwater EcologyInstitute of HydrologyInstituto of Terrestrial EcologyInstitute of Virology & Environmental Microbiology

Natural Environment Research Council