Exe Catchment Flood Management Plan Summary Report June 2012 Managing Flood Risk We Are the Environment Agency
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Exe Catchment Flood Management Plan Summary Report June 2012 managing flood risk We are the Environment Agency. It’s our job to look after your environment and make it a better place – for you, and for future generations. Your environment is the air you breathe, the water you drink and the ground you walk on. Working with business, Government and society as a whole, we are making your environment cleaner and healthier. The Environment Agency. Out there, making your environment a better place. Published by: Environment Agency Manley House Kestrel Way Exeter EX2 7LQ Tel: 0870 8506506 Email: [email protected] www.environment-agency.gov.uk © Environment Agency All rights reserved. This document may be reproduced with prior permission of the Environment Agency. June 2012 Introduction I am pleased to introduce our summary of the Exe Catchment Flood Management Plan (CFMP). This CFMP gives an overview of the flood risk in the Exe catchment and sets out our preferred plan for sustainable flood risk management over the next 50 to 100 years. The Exe CFMP is one of 77 CFMPs for England and The primary source of flooding in the Exe catchment is Wales. Through the CFMPs, we have assessed inland from rivers, particularly where prolonged periods of flood risk across all of England and Wales for the first rainfall lead to a saturated catchment. There is also a time. The CFMP considers all types of inland flooding, risk of significant tidal flooding around the Exe estuary from rivers, ground water, surface water and tidal and problems associated with tide-locking of the flooding, but not flooding directly from the sea (coastal tributary streams. The greatest number of people and flooding), which is covered by Shoreline Management properties at risk are in Exeter and Tiverton and on the Plans (SMPs). Our coverage of surface and ground towns around the estuary. Historically, it is in these water is however limited due to a lack of available locations that the greatest numbers of properties have information. been flooded in the past. The role of CFMPs is to establish flood risk management We cannot reduce flood risk on our own, we will policies which will deliver sustainable flood risk therefore work closely with all our partners to improve management for the long term. This is essential if we the co-ordination of flood risk activities and agree the are to make the right investment decisions for the most effective way to manage flood risk in the future. future and to help prepare ourselves effectively for the We have worked with others including: Devon County impact of climate change. We will use CFMPs to help us Council, Natural England, South West Water and the target our limited resources where the risks are National Farmers Union to develop this plan. greatest. This is a summary of the main CFMP document, if you This CFMP identifies flood risk management policies to need to see the full document an electronic version can assist all key decision makers in the catchment. It was be obtained by emailing produced through a wide consultation and appraisal [email protected] process, however it is only the first step towards an or alternatively paper copies can be viewed at any of integrated approach to Flood Risk Management. As we our offices in South West Region. all work together to achieve our objectives, we must monitor and listen to each others progress, discuss what has been achieved and consider where we may need to review parts of the CFMP. Richard Cresswell South West Regional Director Environment Agency Exe Catchment Flood Management Plan 1 Contents 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 Headwaters and high ground sub-area 12 2 Greater Exeter sub-area 14 3 Tiverton sub-area 16 4 Cullompton sub-area 18 5 East of Exeter sub-area 20 6 Exe Estuary sub-area 21 7 Mid Exe and Creedy sub-area 23 Map of CFMP policies 25 2 Environment Agency Exe Catchment Flood Management Plan The purpose of a CFMP in managing flood risk CFMPs help us to understand the • Internal Drainage Boards (IDB), CFMPs aim to promote more scale and extent of flooding now and water companies and other sustainable approaches to in the future, and set policies for utilities to help plan their managing flood risk. The policies managing flood risk within the activities in the wider context of identified in the CFMP will be catchment. CFMPs should be used to the catchment; delivered through a combination of inform planning and decision different approaches. Together with • transportation planners; making by key stakeholders such as: our partners, we will implement • land owners, farmers and land these approaches through a range • the Environment Agency, who will managers that manage and of delivery plans, projects and use the plan to guide decisions operate land for agriculture, actions. on investment in further plans, conservation and amenity projects or actions; The relationship between the CFMP, purposes; delivery plans, strategies, projects • Regional Assemblies and local • the public and businesses to and actions is shown in Figure 1. authorities who can use the plan enhance their understanding of to inform spatial planning flood risk and how it will be activities and emergency managed. planning; Figure 1. The relationship between CFMPs, delivery plans, projects and actions Policy planning • CFMPs and Shoreline Management Plans. • Action plans define requirement for delivery plans, projects and actions. Policy delivery plans (see note) Projects and actions • Influence spatial planning to reduce risk and • Make sure our spending delivers the best restore floodplains. possible outcomes. • Prepare for and manage floods (including local • Focus on risk based targets, for example numbers Flood Warning plans). of households at risk. • Managing assets. • Water level management plans. • Land management and habitat creation. Note: Some plans may not be led by us – we may identify the • Surface water management plans. need and encourage their development. Environment Agency Exe Catchment Flood Management Plan 3 Catchment overview The Exe CFMP comprises the In the north of the catchment, the The main areas of urban catchments of the River Exe and its Rivers Exe and Barle rise on the open development are to the south of the tributaries, as well as those of the wet moorland of Exmoor and flow catchment. In addition to Exeter, coastal streams that drain direct to south-east through steep sided these urban areas include Tiverton, the Exe estuary. The catchment wooded valleys. The rivers are Cullompton, Crediton (which is not at extends across several different confined within steep, narrow valleys risk of flooding), and the towns landscape types, from Exmoor in the that, in the upper reaches, respond around the Exe estuary, principally north, the wide floodplains and river rapidly to rainfall. Exmouth to the east, and Dawlish to valleys to the north of Exeter, to the the west. The remainder of the Then the Exe floodplain widens smaller tributary streams of the catchment is predominantly rural, through the gently undulating Devon estuary to the south. with smaller villages and minor landscape past Tiverton to Exeter. settlements, and is dominated by The area is environmentally rich, Just upstream of Exeter, the Exe is agriculture, particularly grazing. containing a large number of joined by two major tributaries, the statutorily designated sites. There Creedy, to the west, and the Culm, to The geology of the Exe catchment are two Areas of Outstanding Natural the east. The wide floodplains of the spans 400 million years. The oldest Beauty (AONB), three Special Areas lower reaches of the Exe and Culm rocks - Devonian siltstones, of Conservation (SAC), 31 Sites of provide considerable floodwater sandstones and shales - are in the Special Scientific Interest (SSSI), and storage, this attenuates and reduces uplands of Exmoor. Permo-Triassic 146 Scheduled Monuments. peak flows. sandstones, mudstones and breccias are found in the middle and The Exe CFMP covers an area of some The Exe finally flows into the Exe eastern parts of the catchment. With 1,500 square kilometres (580 square estuary immediately to the south of sands and muds being deposited in miles). Annual rainfall ranges from Exeter. The River Clyst and a number the Exe Estuary as the most recent more than 2,300mm (90in) in upland of smaller tributary streams also flow geological activity. areas to less than 800mm (32in) on directly into the estuary, both to the the coast - the England and Wales west and to the east. average is 920mm (36in). 4 Environment Agency Exe Catchment Flood Management Plan Map 1. Location and extent of the Exe CFMP area Legend Exe CFMP Barnstaple Urban areas Main rivers South Molton Railway Wellington Motorway Tiverton Cullompton Crediton N Honiton Exeter Okehampton Sidmouth Bovey Tracy Exmouth Dawlish 0 4 8 12 16 Kilometres © Crown Copyright. Environment Agency 100026380. ➜ Coastguards rescue residents from a flooded caravan park at Dawlish Warren in December 2000 Photo: Guy Newman/Apex Environment Agency Exe Catchment Flood Management Plan 5 Current and future flood risk Overview of the current flood risk What is at risk? Flood risk has two components: the There is also a risk of significant The main risks to people, property chance (probability) of a particular tidal flooding around the estuary, and the environment across the flood and the impact (or with problems associated with tide- catchment are from the rivers and consequence) that the flood would locking of the tributary streams. the tide. have if it happened. The probability The greatest number of people and In total, approximately 11,000 of a flood relates to the likelihood of property at risk is from the River Exe properties in the Exe catchment are a flood of that size occurring within a in Exeter and Tiverton, and the at risk from a 1% annual probability year period.