East Cornwall Catchment Flood Management Plan...Bude, Bodmin, Looe, Lostwithiel, Wadebridge, and...

managingflood risk

Summary Report June 2012

East Cornwall Catchment Flood Management Plan

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June 2012

Environment Agency East Cornwall Catchment Flood Management Plan 1

Introduction

I am pleased to introduce our summary of the East Cornwall

Catchment Flood Management Plan (CFMP). This CFMP gives an

overview of the flood risk in the East Cornwall catchment and sets

out our preferred plan for sustainable flood risk management over

the next 50 to 100 years.

The East Cornwall CFMP is one of 77 CFMPs for Englandand Wales. Through the CFMPs, we have assessedinland flood risk across all of England and Wales for thefirst time. The CFMP considers all types of inlandflooding, from rivers, ground water, surface water andtidal flooding, but not flooding directly from the sea(coastal flooding), which is covered by ShorelineManagement Plans (SMPs). Our coverage of surfaceand ground water is however limited due to a lack ofavailable information.

The role of CFMPs is to establish flood risk managementpolicies which will deliver sustainable flood riskmanagement for the long term. This is essential if weare to make the right investment decisions for thefuture and to help prepare ourselves effectively for theimpact of climate change. We will use CFMPs to help ustarget our limited resources where the risks aregreatest.

This CFMP identifies flood risk management policies toassist all key decision makers in the catchment. It wasproduced through a wide consultation and appraisalprocess, however it is only the first step towards anintegrated approach to Flood Risk Management. As weall work together to achieve our objectives, we mustmonitor and listen to each others progress, discusswhat has been achieved and consider where we mayneed to review parts of the CFMP.

Flood risk affects people and property across the EastCornwall catchment, but particularly in the areas ofBude, Bodmin, Looe, Lostwithiel, Wadebridge, andPolperro. Various flood events have demonstrated thatwhile the numbers of properties at risk across EastCornwall may be relatively low compared with otherareas of the country, the risk to life, and communitydisruption caused by flooding can be significant.

We cannot reduce flood risk on our own, we willtherefore work closely with all our partners to improvethe co-ordination of flood risk activities and agree themost effective way to manage flood risk in the future.We have worked with others including: CornwallCouncil, Natural England, South West Water and theNational Farmers Union to develop this plan.

This is a summary of the main CFMP document, ifyouneed to see the full document an electronic versioncan be obtained by emailing [email protected] or alternatively paper copies can be viewed at any ofour offices in South West Region.

Richard CresswellSouth West Regional Director

2 Environment Agency East Cornwall Catchment Flood Management Plan

The purpose of a CFMP in managing flood risk 3

Catchment overview 4

Current and future flood risk 6

Future direction for flood risk management 10

Sub-areas

1 Bodmin Moor sub-area 12

2 Bude and Stratton sub-area 14

3 Camel Tidal sub-area 15

4 South Coast Tidal sub-area 16

5 North Coast sub-area 18

6 Camel Valley sub-area 20

7 Fowey and Seaton Valleys sub-area 22

8 Gannel and Mawgan Vale sub-area 23

9 Welcombe and Coombe Valleys sub-area 24

Map of CFMP policies 25

Contents


The purpose of a CFMP in managing flood riskCFMPs help us to understand thescale and extent of flooding now andin the future, and set policies formanaging flood risk within thecatchment. CFMPs should be used toinform planning and decisionmaking by key stakeholders such as:

• the Environment Agency, who willuse the plan to guide decisionson investment in further plans,projects or actions;

• Regional Assemblies and localauthorities who can use the planto inform spatial planningactivities and emergencyplanning;

• Internal Drainage Boards (IDB),water companies and otherutilities to help plan theiractivities in the wider context ofthe catchment;

• transportation planners;

• land owners, farmers and landmanagers that manage andoperate land for agriculture,conservation and amenitypurposes;

• the public and businesses toenhance their understanding offlood risk and how it will bemanaged.

Figure 1. The relationship between CFMPs, delivery plans, projects and actions

CFMPs aim to promote moresustainable approaches tomanaging flood risk. The policiesidentified in the CFMP will bedelivered through a combination ofdifferent approaches. Together withour partners, we will implementthese approaches through a rangeof delivery plans, projects andactions.

The relationship between the CFMP,delivery plans, strategies, projectsand actions is shown in Figure 1.

Policy planning• CFMPs and Shoreline Management Plans.

• Action plans define requirement for deliveryplans, projects and actions.

Note: Some plans may not be led by us – we may identify theneed and encourage their development.

Policy delivery plans (see note)• Influence spatial planning to reduce risk and

restore floodplains.

• Prepare for and manage floods (including localFlood Warning plans).

• Managing assets.

• Water level management plans.

• Land management and habitat creation.

• Surface water management plans.

Projects and actions• Make sure our spending delivers the best

possible outcomes.

• Focus on risk based targets, for example numbersof households at risk.


The East Cornwall CFMP area liesnear the south-westerly tip of the UKmainland. The CFMP area is madeup of two relatively large catchments,the River Fowey and the River Camel,plus a large number of smaller rivercatchments. This includes the twomajor estuaries of the Fowey andCamel. The area is environmentallyrich with many importantenvironmental locations. The areahas a rich mining heritage with anumber of locations in the areaawarded World Heritage Site status.

The East Cornwall CFMP covers anareas of some 1,400 squarekilometres (540 square miles). Thetopography of the CFMP catchment isvaried. The main area of high groundis Bodmin Moor, where the River

Catchment overview

Camel and the River Fowey bothspring. The remainder of the CFMPcatchment is made up of a number ofdiscrete catchments, many of whichare small and steep.

There are two underlying classes ofgeology in the area. The south andnorth of the area are dominated byDevonian slates. To the east BodminMoor is mainly granites that haveintruded into the earlier slates. Thepresence of granite at the surfaceleads to a high percentage of surfacerun-off. This in combination with thesteep gradient of tributaries drainingoff the moor, such as the WarlegganRiver and St Neot River, leads to arapid (or "flashy") response torainfall in the upper reaches and onthe north coast.

The annual rainfall ranges from morethan 1,800mm (70in) over BodminMoor to less than 850mm (33in) onthe coast. The England and Walesaverage is 920mm (36in).

The catchment is predominantlygrassland, arable, horticultural, andwoodland. Only five per cent isurbanised. The principal urbancentres are Newquay, Liskeard,Bodmin, Bude and Wadebridge.

There are six Areas of OutstandingNatural Beauty (AONB), eight SpecialAreas of Conservation (SAC), twoNational Nature Reserves, 46 Sites ofSpecial Scientific Interest (SSSI), and500 Scheduled Monuments.


Map 1. Location and extent of the East Cornwall CFMP area

© Crown Copyright. Environment Agency 100026380.

Legend

East CornwallCFMP

Urban areas

Main rivers

Railway

Motorway

St Austell

BodminLiskeard

Wadebridge

Newquay

Lostwithiel

0 4 8 12 16Kilometres

Bude

Launceston

Fowey

PolzeathCamelford

N

➜Cows retreat to higherground next to the RiverCamel at Slaughterbridgenear Camelford in August2004


Current and future flood risk

Flood risk has two components: thechance (probability) of a particularflood and the impact (orconsequence) that the flood wouldhave if it happened. The probabilityof a flood relates to the likelihood ofa flood of that size occurring within aone year period. It is expressed as apercentage. For example, a 1% floodhas a 1% chance or 0.01 probabilityof occurring in any 1 year, and a0.5% chance or 0.005 probability ofoccurring in any one year.

Flood extents and depths are basedon our Flood Map. These maps donot take into account the presenceof any flood alleviation schemes andso show the worst case scenario fora 1% and a 0.1% annual probabilityflood. The CFMP considers floodingfrom the tide within a rivercatchment where the still water levelof the tide creates flood risk either inisolation or in combination with riverflows.

Previous flood incidents include:

• The 1976 flood in Polperro whereone man was drowned and 83properties were flooded by theRiver Pol;

• In August 2004, Boscastle andthe surrounding area was hit byserious flooding caused by anextremely rare rain storm. Sixtyproperties were flooded and therisk to life was severe. A majoremergency response was initiatedand no lives were lost.

• The October 2004 flood eventwhere over 70 properties wereflooded by high tides in Looe andFowey.

Although the numbers of propertiesat risk in East Cornwall may berelatively low, the risk to life andcommunity disruption caused byflooding can be great. Particularareas of risk include Bude, Bodmin,Looe, Lostwithiel, Wadebridge, andPolperro.

Flood alleviation schemes thatreduce flood risk have beenconstructed in a number of locationsin response to flooding incidents.Locations include Bodmin, Bude,Camelford and Wadebridge. Alongwith other schemes in East Cornwall,these help reduce flood risk to1,153 residential properties and588 commercial properties.

Overview of the current flood risk

The main risks to people, propertyand the environment across thecatchment are from the rivers andthe tide. Currently there are around1,200 residential and commercialproperties at risk from a 1% annualprobability flood, not taking intoaccount current flood defences.Around 2200 people are at risk in themain communities of East Cornwall.

Four Special Areas of Conservation(SACs) are at risk along with oneNational Nature Reserve and 25 sitesof Special Scientific Interest (SSSI).

Schools, health centres, surgeriesand residential homes are at risk,along with Looe ambulance andpolice stations, and the fire stationsat Wadebridge and Bude.

What is at risk?

Table 2. Critical infrastructure at risk:

5 electricity substations, 1 wastewater treatment works, 2 railway lines, 9 A roads, and 5 B roads


Table 1. Locations of towns and villages with 25 or more properties at risk in a 1% annual probability river flood

Map 2. Flood risk to property in a 1% annual probability river flood, taking into account current flood defences


Legend

Properties with a 1%chance of flooding

20 - 50

51 - 100

101 - 200

201 - 300

301 - 400

East Cornwall CFMPMain rivers

Wadebridge

Newquay

Lostwithiel

Bude

Camelford


Padstow

Looe

N

Number of properties at risk Locations

100 to 500 Wadebridge, Looe, Bude, Lostwithiel

50 to 100 Padstow

25 to 50 Boscastle, Stratton, Tremar, Newquay


How we currently manage the risk

Our activity is prioritised on a riskbasis. Our main activities include:

• Flood risk mapping – A major partof the programme is Flood ZoneImprovements and HazardMapping. This is focused onimproving the mapping at high-risk locations.

• Managing development – Ourdevelopment control teamsupports the planning process byensuring that new developmentshave the appropriate flood riskassessments and follow PPS25(Planning Policy Statement onDevelopment and Flood Risk).

• Flood warning – Systems are inplace for the following riverreaches: River Camel, Camelfordto Wadebridge; River Allen,Penvose to Sladesbridge; RiverFowey, Trekeivesteps toLostwithiel; River Seaton,Trebrownbridge to Seaton; RiverPol at Polperro; River Neet,

Woolstone Mill to Bude, and theRiver Strat from Bush toHelebridge. Major Incident Plansare in place for Wadebridge,Bude, Camelford, Padstow, andBodmin.

• Flood defence schemes – We have flood defence schemesat Bodmin, Boscastle, Bude,Camelford, Fowey, Helebridge,Lostwithiel, Polperro,Sladesbridge, Stratton andWadebridge.

• Maintenance and operation – We operate and maintain flooddefence banks and structures,with local authorities carrying outfurther work.

The distribution of potential floodrisk from rivers and tides isillustrated in Map 2 for a flood with a1% annual probability (0.5% fortides) of occurring or beingexceeded.

The greatest concentration ofproperties at risk of flooding is atWadebridge. Here some 357properties are defended from bothriver and tidal flooding. Looerepresents the next greatestconcentration, with 241 propertiesat risk of tidal flooding.

Large numbers are at risk from bothtidal and river flooding at Bude andLostwithiel, and from river floodingat Bodmin and Polperro.

In addition to these locations, thereare risks of surface water flooding,which can be deep and fast flowing,across much of the catchment.However, further studies followingon from the CFMP are needed by usand our partners to quantify thispotential risk.

Where is the risk?

➜This couple had to be rescued byhelicopter from the roof of theirbungalow after it was surrounded byflood waters from the River Neet inAugust 2004.


The impact of climate change and future flood risk

In the future, flooding will beinfluenced by climate change,changes in land use (for example,urban development) and rural landmanagement. In the East Cornwallcatchment, climate change isexpected to have the greatest impacton flood risk. The following futurescenario for climate change wasused in the CFMP:

• 20% increase in peak flow in allwatercourses. This will increasethe probability of large-scale floodevents,

• a total sea level rise of 500mm bythe year 2100. This will increasethe probability of tidal flooding.

Using river models we estimate thatby 2100, around 1,590 properties inthe key settlements (Figure 2) maybe at risk from a 1% annual

probability flood, rising from thecurrent 980 properties. Flood riskfrom rivers increases mainly in thecommunities of Wadebridge, Looe,Bude, Polperro and Lostwithiel.

The sensitivity testing undertakenshowed that urban developmentcould affect flood risk in Bodmin andNewquay. We found that a 10%increase in urban developmentaround these towns could increaseflows by 4.5% and 6% respectively.With the rural nature of thecatchment we found that run-off fromagricultural land plays a part in floodrisk.

An increase in run-off of 15%,combined with a reduction in thetime it takes flows to peak, showedthat the average increase in flowswould be 10%.

0

50

100

150

200

250

300

350

400

Wadebridge Looe Bude Polperro Lostwithiel Bodmin Boscastle Stratton Tremar Newquay Lanivet Camelford

Current Future

Num

ber o

f Pro

pert

ies

at F

lood

Ris

k

Figure 2. Current and future (2100) flood risk to property from a 1% annualprobability river flood, ignoring the presence of current flood defences

We have therefore based ourmodelling of future flood risk onclimate change, urban developmentand land management.


Approaches in each sub-area

We have divided the East Cornwall catchment into ninedistinct sub-areas which have similar physicalcharacteristics, sources of flooding and level of risk. We have identified the most appropriate approach tomanaging flood risk for each of the sub-areas andallocated one of six generic flood risk managementpolicies, shown in Table 3.

To select the most appropriate policy, the plan hasconsidered how social, economic and environmentalobjectives are affected by flood risk managementactivities under each policy option.

Map 3. East Cornwall sub-areas

Bude

Fowey

Truro

Bodmin

NewquaySaltash

Liskeard

Polzeath

Delabole

Torpoint

Camelford

St Blazey

Callington

St Austell

Launceston

i

Wadebridge

LostwithielSt Columb Road

Tywardreath



N

LegendEast Cornwall CFMP

Sub-area

Bodmin Moor (Policy 6)

Bude and Sutton (Policy 5)

Camel Tidal (Policy 5)

South Coast Tidal (Policy 5)

North Coast Rivers (Policy 4)

Camel Valley (Policy 4)

Fowey and Seaton Valleys (Policy 4)

Gannel and Mawgan Vale (Policy 3)

Welcombe and Coombe Valleys (Policy 1)

1

2

3

4

5

6

7

8

9

Future direction for flood risk management

➜ Looe, Cornwall. March 2006


Policy 1

Areas of little or no flood risk where we will continue to monitor and advise

This policy will tend to be applied in those areas where there are very few properties at risk of flooding. It reflects a commitment to work with the natural flood processes as far as possible.

Policy 2

Areas of low to moderate flood risk where we can generally reduce existing flood risk management actions

This policy will tend to be applied where the overall level of risk to people and property is low to moderate.It may no longer be value for money to focus on continuing current levels of maintenance of existing defencesif we can use resources to reduce risk where there are more people at higher risk. We would therefore reviewthe flood risk management actions being taken so that they are proportionate to the level of risk.

Policy 3

Areas of low to moderate flood risk where we are generally managing existing flood risk effectively

This policy will tend to be applied where the risks are currently appropriately managed and where the risk offlooding is not expected to increase significantly in the future. However, we keep our approach under review,looking for improvements and responding to new challenges or information as they emerge. We may reviewour approach to managing flood defences and other flood risk management actions, to ensure that we aremanaging efficiently and taking the best approach to managing flood risk in the longer term.

Policy 4

Areas of low, moderate or high flood risk where we are already managing the flood risk effectively but where wemay need to take further actions to keep pace with climate change

This policy will tend to be applied where the risks are currently deemed to be appropriately-managed, butwhere the risk of flooding is expected to significantly rise in the future. In this case we would need to do morein the future to contain what would otherwise be increasing risk. Taking further action to reduce risk will requirefurther appraisal to assess whether there are socially and environmentally sustainable, technically viable andeconomically justified options.

Policy 5

Areas of moderate to high flood risk where we can generally take further action to reduce flood risk

This policy will tend to be applied to those areas where the case for further action to reduce flood risk is mostcompelling, for example where there are many people at high risk, or where changes in the environment havealready increased risk. Taking further action to reduce risk will require additional appraisal to assess whetherthere are socially and environmentally sustainable, technically viable and economically justified options.

Policy 6

Areas of low to moderate flood risk where we will take action with others to store water or manage run-off inlocations that provide overall flood risk reduction or environmental benefits

This policy will tend to be applied where there may be opportunities in some locations to reduce flood risklocally or more widely in a catchment by storing water or managing run-off. The policy has been applied toan area (where the potential to apply the policy exists), but would only be implemented in specific locationswithin the area, after more detailed appraisal and consultation.

Table 3. Policy options


Bodmin Moor

Sub-area 1

The issues in this sub-area

Bodmin Moor area covers the DeLank River and the headwaters ofthe River Fowey. The northern partof Bodmin Moor is within thecatchment of the River Camel whilethe southern part drains to the RiverFowey catchment.

The area is sparsely populated.There are a number of settlementsat risk of flooding from rivers andsurface water run-off includingBlisland and St Neot. There are 28

Our key partners are:

Department for Environment, Foodand Rural Affairs (Defra)

Natural England

National Farmers Union

properties and a number of minorroads at risk of flooding under the1% annual probability flood. Overthe next 100 years, only a furtherone property is expected to be atrisk.

Drainage practices on the moorhave reduced its capacity to storewater. As a result, floodwater enterthe Camel and Fowey rivers morequickly and make flooding worsedownstream.

There are no flood alleviationschemes in the moor area.

Due to the rapid flood response torainfall it is also not possible tooffer specific flood warnings tocommunities using the currenthydrometric infrastructure.

The vision and preferred policy

Policy Option 6 - we will take actionwith others to store water ormanage run-off in locations thatprovide overall flood risk reductionor environmental benefits.

The policy will have no adverseenvironmental impacts and willhave a cumulative benefit for boththe Fowey and Seaton Valley andthe Camel Valley areas. Storingwater on the moor will attenuateflows, prolong greater base flow,and reduce sediment loadingthrough reduced erosion. Theseoutcomes could contribute to adecreased risk of floodingdownstream, particularly atsettlements like Lostwithiel, whilenot adversely affecting flood risk onthe moor itself.


Proposed actions to implement the preferred policy

• Investigate the links between land management practices, run-off and flood risk. Consider options forinfluencing land management practice to reduce flood risk, including encouraging landowners to joinEnvironmental Stewardship programmes and changing drainage practice to attenuate run-off wherethis is likely to have an impact. Any studies would need to consider land management requirements ofthe River Camel SAC.

• Investigate opportunities to reduce flood risk downstream by creating flood storage. Options includeenhancing wetland habitat in the Upper Fowey and using Siblyback Reservoir, Colliford Lake anddisused china clay workings.

Should any flood storage be created the following mitigation must be implemented to avoid negativeimpacts to the River Camel SAC:

- Any storage options must not result in degraded water quality. - At least 90 per cent of the naturalised daily mean flow should remain in the river throughout the year.- Fish passage should not be impeded.- Consider changes in flow regime to ensure no detrimental change to woodland area and structure.

• Use programmes to raise and maintain awareness of flood risk and self-help measures.

Land use planners should designate floodplains and wetland areas as functional floodplain to protectand enhance their storage potential. This will also avoid introduction of further constrictions to floodflows. Where development or redevelopment is permitted in flood risk areas it is essential that robustwarning and evacuation procedures are secured and maintained, and that resistant and resiliencemeasures are fully incorporated into the buildings.


Bude and Stratton

Sub-area 2


The Bude and Stratton areaincludes the River Neet and RiverStrat catchments.

A number of locations arevulnerable to flooding caused byshort, intense rainfall events.Flooding occurs from riversovertopping their banks and fromsurface water run-off. Bude is alsoat risk of tidal flooding.

There are 338 properties, anemergency response centre, the firestation at Bude and one care homenear Flexbury within the 1 per centannual probability flood extent.Over the next 100 years, weestimate that around 30 additionalproperties will be at risk of flooding.Roads could also be subjected toflooding. There are flood alleviationschemes at Stratton, Bude, Flexburyand Helebridge.


Cornwall Council


Policy Option 5 - we can generallytake further action to reduce floodrisk.

This policy allows scope to respondto current flood risk now. A range offlood risk management measurescan be used to reduce risk in thesub-area including communitybased tidal flood warnings at Budeand improvements to lead timewarnings on the rivers Neet andStrat. This policy also allows floodrisk management measures torespond to long-term risks such assea level rise.

Limited impacts to the environmentmay occur from this option and theyshould be mitigated againstthrough the design of flood riskmanagement measures.

Proposed actions to implement thepreferred policy

• Review existing flood risk in Budeand undertake work to reducerisk if justified.

• Use programmes to raise andmaintain awareness of flood riskand self-help measures.

• Support the local planningauthority in the preparation of itsStrategic Flood Risk Assessmentsand associated Local

Development FrameworkDocuments. Land use plannerscan contribute to this policy by,using Local DevelopmentFrameworks to reduce thevulnerability of developmentlocated in flood risk areas.

• Review current facility forrecording tide levels at Bude andimprove if required.

• Create community-basedwarnings for areas at risk of tidalflooding.

• Review and improve floodwarnings on the Neet and Strat iffeasible.

• Further investigate the linksbetween land managementpractices, run-off and flood risk.Consider options for influencingland management practice toreduce flood risk, includingencouraging landowners to joinEnvironmental Stewardshipprogrammes where this is likelyto have an impact.

• Investigate the management ofexisting defences at Stratton,Flexbury and Helebridge.


Sub-area 3

Camel Tidal


Camel Tidal includes the areadraining to the Camel Estuary.

The major source of flood risk in thearea is tidal flooding, withWadebridge being at the greatestrisk. Fluvial flooding is also a risk atplaces such as Polmorla andSladesbridge. Tide-locking is afactor that makes flood risk worse inthese areas.

There is little floodplain storagepotential upstream of settlementsand there are a number of smallcatchments that respond rapidly torainfall.

There are 390 properties, includingan emergency response centre andan electricity substation, as well asroads at risk of flooding. Over thenext 100 years, we estimate that thenumber of properties at risk couldincrease by around 60. There areflood alleviation schemes atPolmorla, Wadebridge, andSladesbridge, with tidal defences atRock and Padstow.


Cornwall Council

South West Water



This policy allows scope to respondto current flood risk now. Throughthis policy the number ofcommercial and residentialproperties at risk of flooding wouldbe reduced and there would be aminor decrease in the extent andduration of flooding of roads.Community assets would alsobenefit from reduced flood risk.

Land use planners have a major rolein the delivering of this policy, bothnow and in the future. ClimateChange will increase the principalrisk of flooding due to sea level rise.It is essential that LocalDevelopment Frameworkdocuments provide a robuststrategy to deal with climate changeadaptation, in particular forWadebridge and the low-lying areasbehind its raised defences.


• Use programmes to raise andmaintain awareness of flood riskand self-help measures.

• Support the local planningauthority in the preparation of itsStrategic Flood Risk Assessments

and associated LocalDevelopment FrameworkDocuments. Ensure PPS25implemented for developmentand in particular at Wadebridge.We expect this will includePlanning policies to addressclimate change adaptation inrelation to flood risks, and forallocations to be directed toareas at lowest flood risk.

• Create community-basedwarnings for areas at risk of tidalflooding.

• Undertake and implementSurface Water Management Plansfor Wadebridge and Padstow.

• Progress with the outcomes ofthe Rapid Response CatchmentStudy when available. This islikely to apply to Polmorla inparticular.


• Investigate the currentmanagement of flood risk on therivers Allen and Camel atSladesbridge and also atPolmorla and Wadebridge.


South Coast Tidal

Sub-area 4


South Coast Tidal includes theFowey Estuary and the catchmentsdraining direct to the coastline tothe east, to just before Downderrry.The main towns are Lostwithiel,Fowey and Looe. There are 408properties at risk of flooding from a1% and 0.5% annual probabilityflood. Over the next 100 years, weestimate the number of properties atrisk could increase in number byaround 70 as a result of the impactsof climate change and land usemanagement.

Tidal flooding is the dominant floodrisk in the area. Looe suffersfrequent flooding from high tideswith around 62 properties at riskfrom a 10% tidal flood. Manyproperties, roads, and the Looerailway line are at risk of flooding.Two electricity substations are atrisk, as is a police station and a StJohn’s Ambulance centre.


Cornwall Council


Natural England




This policy allows scope to respondto current flood risk now. A numberof economic and social assets arecurrently at risk of flooding.

Land use planners must ensure thatany development is carefullydesigned so as not to exacerbateflood risks further.

This policy also allows scope torespond to risk in the future as aresult of sea level rise, particularlyin the communities of Looe, Foweyand Lostwithiel.

Limited impacts to the environmentcould potentially occur from thisoption and must be mitigatedagainst through the design of floodrisk management measures.



• Support the local planning authority in the preparation of its Strategic Flood Risk Assessments andassociated Local Development Framework Documents. Ensure PPS25 is implemented fordevelopments, particularly for Fowey, Looe, Lerryn and Lostwithiel. Land use planners should consideroptions within their Local Development Framework and development control decisions to supportopening up of culverted watercourses to manage flooding and enhance green infrastructure. We wouldexpect planning policy to address climate change adaptation due to sea level rise, especially at Looe,Lostwithiel and Fowey.

• Create community-based warnings for areas at risk of tidal flooding. Use programmes to raise andmaintain awareness of all flood risk and self-help measures.

• Investigate the possibility of installing a tide gauge at either Fowey or Looe for flood warning.

• Further investigate the links between land management practices, run-off and flood risk. Consideroptions for influencing land management practice to reduce flood risk, including encouraginglandowners to join Environmental Stewardship programmes where this is likely to have an impact.

• Investigate measures for reducing flood risk at Looe, Fowey, Polperro and Seaton, from tidal andsurface water flooding.

• Review options to reduce flood risk at Lostwithiel, including improving lead time for flood warning andimproving the standard of protection of current defences. Undertake work to reduce risk if justified.

➜ Shops sandbagged against floods on Fowey’s Town Quay in March 2006


North Coast Rivers

Sub-area 5


North Coast Rivers covers thecatchments between the Camel andthe Strat at Bude. This includes theValency River and River Jordanthrough Boscastle.

Fluvial flood risk is dominant with allwatercourses springing on highground in small catchments andflowing directly to the sea. All riversare of high gradient and vulnerableto ‘flash’ flooding caused by short,intense rainfall events and surfacerun-off.

Flooding has been recorded at manylocations, most notably in August2004.

Whilst there are no majorsettlements, there are some 106properties at risk of flooding from the1% annual probability flood. Overthe next 100 years, we estimate thata further 20 or so properties couldbecome at risk of flooding as a resultof the impact of climate change andland use management.


Cornwall Council

National Trust

Natural England



There is a flood alleviation scheme atBoscastle, although a residual riskhas been identified in the ValencyValley Tree Management Study.Surface water flooding is also beingaddressed with Cornwall’s Highways.


Policy Option 4 - we are alreadymanaging the flood risk effectivelybut we may need to take furtheractions to keep pace with climatechange.

We propose to continue toeffectively manage the flood risk totake further actions where we needto keep pace with climate change.Whilst there are no significantincreases in future risks, the currentrisks to life justify maintaining thestandard of protection.


• Sustain the current flood risk atBoscastle into the future.

• Create specific flood warnings forat risk locations, such asBoscastle.

• Use programmes to raise andmaintain awareness of flood riskand self-help measures, for bothpermanent and temporaryresidents.

• Support the local planningauthority in the preparation of itsStrategic Flood Risk Assessmentsand associated LocalDevelopment FrameworkDocuments.

• Progress with the outcomes ofthe Rapid Response CatchmentStudy when available.


• Targeted channel maintenance,including reducing the incidentsof blockages.

• Act upon the outcomes of theValency Valley Tree ManagementStudy.


➜ Helicopters rescue people trapped in the Boscastle floods of August 2004Photo: Pam Durrant


Camel Valley

Sub-area 6


The Camel Valley covers the RiverCamel and its tributaries upstreamof Wadebridge and the tidal estuary.The major towns are Camelford andBodmin.

The Camel and its tributaries springon high ground and moorland,underlain by impermeable graniteso that the rivers respond quickly torainfall. They flow through narrowwooded valleys with limitedfloodplains to store floodwater.

There are 214 properties at risk offlooding under the 1% annualprobability flood event, withprotection provided for 130properties for this scale of event.

Over the next 100 years, theexpected number of properties atrisk could increase by 30 as a resultof the impact of climate change andland use management


Cornwall Council

Natural England



The major risk of flooding is atBodmin, from both the BodminTown Leat and surface water. Aflood alleviation scheme in Bodminprovides protection for up to the 1per cent annual probability riverflood. The fire station is at risk fromthis flood.



The impacts of climate change andland use management includereducing the standard of protectionoffered by existing flood alleviationschemes (at Camelford andBodmin).

The number of social and economicassets currently at risk of floodingwould not be reduced.

Any development should becarefully designed so as not toexacerbate flood risks further,especially in the Bodmin area. Landuse planners should support thedevelopment of a Surface WaterManagement Plan and itsimplementation in newdevelopment within the Bodminarea.



• Investigate taking further actions in Camelford, Lanivet, and Bodmin to keep pace with climate change,while ensuring measures undertaken avoid negative impacts to the River Camel SAC. Opportunitiesinclude wetland creation at Slaughterbridge.

• Support the local planning authority in the preparation of its Strategic Flood Risk Assessments andassociated Local Development Framework documents.

• Ensure PPS25 is implemented for development particularly at Bodmin and investigate feasibility torelocate the fire station in the town.

• Progress with the outcomes of the Rapid Response Catchment Study when available and undertakeand implement a Surface Water Management Plan for Bodmin.

• Investigate links between land management practices, run-off and flood risk.

• Consider options for influencing land management practice to reduce flood risk, including encouraginglandowners to join Environmental Stewardship programmes where this is likely to have an impact.

• Improve warning times on the Rivers Camel and Allen and the Bodmin Town Leat and raise awarenessof flood risk and self-help measures across the area.

• Targeted channel maintenance and review of structure capacity, to reduce incidents of blockage.

• Improve understanding of the impact of mine workings on flood risk, particularly within the River CamelSAC.

➜ Surface water and Leat flooding at Church Square, Bodmin – September 1993


Fowey and Seaton Valleys

Sub-area 7


The Fowey and Seaton Valleyscovers the Rivers Fowey, Pol, EastLooe, West Looe, and Seaton afterthey drain from the Bodmin Moorarea. The area includes the towns ofLiskeard and Polperro. It excludesthe tidal reaches of the Fowey andthe lower Seaton Valley. The riversflow through incised valleys withlittle floodplain storage so that theyreact quickly to rainfall.

There are 290 properties, roads, awaste water treatment works andtwo electricity sub stations at riskfrom the 1% annual probabilityflood. Over the next 100 years, thenumber of properties at risk couldincrease by around 14 as a result ofthe impacts of climate change andland use management


Cornwall Council

Natural England

Department of Environment, Foodand Rural Affairs (Defra)




The flood alleviation scheme atPolperro provides an appropriatelevel of flood protection today forabout 130 properties, however inthe future this level of protectionwill reduce and risks to life willincrease. This policy intends toallow us to keep pace with climatechange. Our studies have alsoshown a significant flood risk atTremar, although this is notsupported by historical records andfurther work is needed to assess theflood risk at Tremar.

Any development in the area shouldbe carefully designed as not toexacerbate flood risks further.


• Take further action on the RiverPol at Polperro to keep pace withclimate change.

• Use programmes to raise andmaintain awareness of flood riskand self-help measures andImprove flood warning lead timeon River Pol.

• Support the local planningauthority in the preparation of itsStrategic Flood Risk Assessmentsand associated LocalDevelopment Frameworkdocuments. Land Use Plannersshould designate openfloodplains and river corridors asfunctional floodplain to ensurethat their flow capacity is notreduced. Local DevelopmentFrameworks and applicationdecisions should seek to reducethe vulnerability of developmentlocated in flood risk areas.

• Targeted channel maintenance,including reducing the incidentsof blockages.

• Investigate links between landmanagement practices, run-offand flood risk. Consider optionsfor influencing land managementpractice to reduce flood risk,including encouraginglandowners to join EnvironmentalStewardship programmes wherethis is likely to have an impact.

• Review flood risk at Tremar andimprove A38 drainage in theGlynn Valley.

• Progress with the outcomes ofthe Rapid Response CatchmentStudy when available. This islikely to apply to Polperro inparticular.


Gannel and Mawgan Vale

Sub-area 8


Gannel and Mawgan Vale covers thecatchments of the Rivers Ganneland Menalhyl, and the coastalstreams to the north up to Trevone.The area includes the town ofNewquay.

The rivers are of low gradient.Underlying geology means thatrivers still respond rapidly torainfall, with the small catchmentsresponding quickest. The majorrisks of flooding are from rivers andsurface water. Some tidal floodinghas been recorded at Newquay.Surface water and inadequatedrainage have also caused floodingat a number of locations.

There are 238 properties at risk offlooding for the 1% annualprobability flood, it is also expectedthat three A roads, two B roads and4km of minor roads would also besubjected to flooding. Over the next100 years, we estimate that anadditional 17 properties will be atrisk of flooding in the future as aresult of the impacts of climatechange and land use management.


Cornwall Council


Policy Option 3 - we are generallymanaging flood risk effectively.

A number of economic and socialassets are at risk of infrequentflooding in the long-term, and whileflood risk to these assets will getworse, this remains a relatively lownumber of assets. Risk to life is notestimated to increase. Furthermore,this option does not result in anysignificant impacts on theenvironment.

Future impacts from urbandevelopment in Newquay need tobe avoided through ensuring PPS25requirements are met for newdevelopments. In particular thismay be achieved through strategicplanning for use of SustainableDrainage Systems.


• Continue to maintain existingdefences at Mawgan Porth and StColumb Major.

• Continue to use programmes toraise and maintain awareness offlood risk and self-helpmeasures.

• Support the local planningauthority in the preparation of itsStrategic Flood Risk Assessmentsand associated LocalDevelopment FrameworkDocuments. Ensure PPS25implemented for developmentand in particular at Newquay. Weconsider that this should includea Surface Water ManagementPolicy for allocation of any majordevelopment within or aroundNewquay.

• Review flood risk in Newquay andtake action to ensure it does notincrease as a result of newdevelopment.

• Investigate the links betweenland management practices, run-off and flood risk. Consideroptions for influencing landmanagement practice to reduceflood risk, including encouraginglandowners to join EnvironmentalStewardship programmes. wherethis is likely to have an impact.


Sub-area 9


Cornwall Council


Welcombe and Coombe Valleyscovers the coastal rivers north ofBude including the Marsland Waterand the villages of Morwenstow andKilkhampton.

There are no major conurbations inthe area.

Fluvial flood risk is dominant withall watercourses springing on highground and draining smallcatchments directly to the sea. Therivers have high gradients and arevulnerable to ‘flash’ floodingcaused by short, intense rainfallevents and surface run-off.

There are 9 properties considered tobe at risk of flooding from the 1%annual probability flood. Howeverwe are not aware of any propertyflooding having been recorded.Over the next 100 years, we do notexpect the number of properties atrisk to increase as a result of theimpacts of climate change and landuse management.

Welcombe andCoombe Valleys


Policy Option 1 - we will continue tomonitor and advise.

No active intervention is the mostappropriate option to manageincreasing flood risk in the longterm as there is no increase innumber of properties at risk offlooding, and no community assetsat risk. There is the potential thatCoombe Mill SSSI may be impactedby an increase in frequency, depthand duration of flooding. Thisimpact will need to be assessedand consent may be required fromNatural England.


• No further action is proposed,but we will continue to monitorand advise.

Land use planners should designateall floodplains as functionalfloodplain to maximise their role incontrolling flood risks.


Map of CFMP policies

Map of the policies in the East Cornwall catchment


N

St Austell

BodminLiskeard

Saltash

Wadebridge

Newquay Lostwithiel

Bude

Launceston

Fowey

Polzeath

Camelford


Legend

Main rivers

Urban areas

Preferred approach

Policy 1

Policy 2

Policy 3

Policy 4

Policy 5

Policy 6

East Cornwall CFMP

1

2

3

44

5

6

7

8

9

1 Bodmin Moor

2 Bude and Stratton

3 Camel Tidal

4 South Coast Tidal

5 North Coast Rivers

6 Camel Valley

7 Fowey and Seaton Valleys

8 Gannel and Mawgan Vale

9 Welcombe and Coombe Valleys

The sub-areas

GESW0612BWPP-E-E

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East Cornwall Catchment Flood Management Plan...Bude, Bodmin, Looe, Lostwithiel, Wadebridge, and...

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