River Derwent Catchment Flood Management Plan Summary Report December 2009 Managing Flood Risk We Are the Environment Agency
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River Derwent Catchment Flood Management Plan Summary Report December 2009 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 Richard Fairclough House Knutsford Road Warrington WA4 1HT 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. December 2009 Introduction I am pleased to introduce our summary of the River Derwent Catchment Flood Management Plan (CFMP). This CFMP gives an overview of the flood risk in the River Derwent catchment and sets out our preferred plan for sustainable flood risk management over the next 50 to 100 years. The River Derwent CFMP is one of 77 CFMPs for England suffered severe flooding in November 2009. By 2100, and Wales. Through the CFMPs, we have assessed we estimate that there will be 1660 properties at risk in inland flood risk across all of England and Wales for a 1% annual fluvial flood event, this is a 66% increase. the first time. The CFMP considers all types of inland There is also a tidal risk from estuaries in the CFMP flooding, from rivers, groundwater, surface water area, including the towns of Workington and Maryport. and tidal flooding, but not flooding directly from the Although this document is a summary of the main sea (coastal flooding), which is covered by Shoreline CFMP document which sets out the long term policies Management Plans (SMPs). Our coverage of surface for this catchment, we have taken the opportunity to and groundwater is however limited due to a lack of update this document with information from the recent available information. (Nov. 2009) flood. 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 are to make the right investment decisions for the the most effective way to management flood risk in future and to help prepare ourselves effectively for the future. To develop this plan and ensure social, the impact of climate change. We will use CFMPs to economic and environmental issues were taken help us target our limited resources where the risks into account we worked with, and consulted many are greatest. organisations. These included United Utilities, Allerdale Borough Council, Cumbria County Council, Natural This CFMP identifies flood risk management policies to England, National Trust, Lake District National Park assist all key decision makers in the catchment. It was Authority, RSPB, NFU and Defra. produced through a wide consultation and appraisal process, however it is only the first step towards an This is a summary of the main CFMP document, if you integrated approach to Flood Risk Management. As we need to see the full document an electronic version all work together to achieve our objectives, we must can be obtained by emailing enquiries@environment- monitor and listen to each others progress, discuss agency.gov.uk or alternatively paper copies can be what has been achieved and consider where we may viewed at any of our offices in North West Region. need to review parts of the CFMP. In the Derwent catchment, over 1000 residential and commercial properties are at a 1% annual risk of flooding from rivers. Over 50% of the properties at risk are concentrated in the towns of Keswick, Cockermouth Tony Dean and Wigton. Keswick, Cockermouth and Workington Regional Director Environment Agency River Derwent 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 Keswick 12 2 Cockermouth 14 3 Wigton 16 4 Cocker and Marron 17 5 Upper Derwent 18 6 Lower Derwent 20 7 Ellen 21 8 Workington 22 9 Maryport 23 10 Wampool and Waver 24 Map of CFMP policies 26 Cover photo reproduced with kind permission of Tony West 2 Environment Agency River Derwent Catchment Flood Management Plan The purpose of a CFMP in managing flood risk CFMPs help us to understand the • Internal Drainage Board, water CFMPs aim to promote more scale and extent of flooding now companies and other utilities to sustainable approaches to managing and in the future, and set policies help plan their activities in the flood risk. The policies identified in for managing flood risk within the wider context of the catchment. the CFMP will be delivered through a catchment. CFMPs should be used combination of different approaches. • Transportation planners. to inform planning and decision Together with our partners, we making by key stakeholders such as: • Landowners, farmers and will implement these approaches land managers who manage through a range of delivery plans, • The Environment Agency, who will and operate land for projects and actions. use the plan to guide decisions agriculture, conservation on investment in further plans, The relationship between the CFMP, and amenity purposes. projects or actions. delivery plans, strategies, projects • The public and businesses to and actions is shown in figure 1. • Regional planning bodies and enhance their understanding local authorities who can use of flood risk and how it will the plan to inform spatial be managed. planning activities and emergency 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 • Make sure our spending delivers the best and restore floodplains. possible outcomes. • Prepare for and manage floods • Focus on risk based targets, for example (including local Flood Warning plans). numbers 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 • Surface water management plans. identify the need and encourage their development. Environment Agency River Derwent Catchment Flood Management Plan 3 Catchment overview The Derwent CFMP area lies Bassenthwaite Lake, Derwent Water, are mainly located within the within North West Cumbria. Thirlmere Reservoir, Buttermere and uplands of the Derwent catchment. Most of the CFMP area is within Crummock Water. The River Ellen In addition, some coastal areas the administrative boundary of covers the central part of the CFMP may be subject to tidal flooding Allerdale Borough Council, with area and drains into the Irish Sea including parts of Workington, a significant proportion within at Maryport. The Rivers Wampool Maryport, Flimby and Silloth. the Lake District National Park and Waver cover the upper portion This CFMP area has a particularly Authority (LDNPA). It covers a total of the CFMP area and drain into the high environmental and landscape area of 1,235km2 and has four Solway Firth at Moricambe Bay. value, reflected in its two main significant river systems (Derwent, The catchments within the designations. Much of the area is Ellen, Wampool and Waver) which Derwent CFMP receive a great deal within the Lake District National drain the northern fells of the Lake of rainfall. Combined with the Park and it contains one Area of District and the Solway Basin into impermeable underlying geology Outstanding Natural Beauty (AONB). the Irish Sea. The River Derwent and waterlogged upland soils, this Many of its sites have international, and its major tributaries cover the produces large amounts of run-off. European and national southern part of the CFMP area and The main risk areas on these rivers environmental designations, rise in the high peaks of the Lake are Cockermouth and Keswick (on including over 25 sites of special District draining into the Irish Sea the Derwent) and Wigton (on Wiza scientific interest and 11 scheduled at Workington. There are several Beck). There are many smaller ancient monuments. lakes which play a key role in the settlements at risk from localised Derwent catchment, including rapid run-off from the fells which Coledale Beck at Braithwaite 4 Environment Agency River Derwent Catchment Flood Management Plan Map 1 Main Features of River Derwent CFMP area Environment Agency River Derwent Catchment Flood Management Plan 5 Current and future flood risk Overview of the current flood risk Flood risk has two components: The main sources of flooding in the some areas because the ground the chance (probability) of a Derwent catchment are as follows: is steep and impermeable, these particular flood and the impact (or areas are generally outside consequence) that the flood would • River flooding has its largest the urban areas. Very little have if it happened. The probability effects in Keswick from the Rivers information on surface water of a flood relates to the likelihood of Greta and Derwent, Cockermouth flooding in the Derwent CFMP a flood of that size occurring within is affected again from the area was available but there are a one year period, it is expressed Derwent and the River Cocker, known surface water flooding as a percentage. For example, Wigton floods from Wiza Beck issues from the Cuddy Beck in a 1% flood has a 1% chance or and Allonby from Crookhurst Keswick and in Greysouthern, probability of occurring in any one Beck.