Environment Agency North West Region NATIONAL LIBRARY & INFORMATION SERVICE ANGLIAN REGION Kingfisher House, Goldhay Way, Orton Goldhay, Peterborough PE2 SZR Jeff Lawrenson Regional Flood Defence Manager Richard Fairclough House Knutsford Road Warrington WA4 1HG Tel: 01925 653 999 Fax: 01925 415 961 ISBN 185705 572 1 ©Environment Agency l All rights reserved. No part of this document may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the Environment Agency. Cover: Flooding in Common Lane Brook area, Leigh (30th October 2000) HO-4/01-150-A Printed on recycled paper Floods Report October/November 2000 Environment Agency North West ENVIRONMENT AGENCY NORTH WEST REGION OCTOBER/NOVEMBER 2000 FLOODS REPORT CONTENTS List of Tables..........................................................................................................................5 List of Figures.........................................................................................................................7 List of Abbreviations............................................................................................................9 Executive Summary............................................................................................................11 1. Introduction.............................................................................................................17 1.1 Introduction................................................................................................. 17 1.2 Extent of Flooding in North West Region...............................................17 2. Event Management................................................................................................21 2.1 Procedures....................................................................................................21 2.2 Incident/Forecasting Room Times & HELPs/SITREP..........................22 2.3 Liaison, Communications..........................................................................23 2.3.1 Internal.........................................................................................................23 2.3.2 Professional Partners...................................................................................24 2.3.3 Media and the Public...................................................................................25 2.4 Numbers Of Staff Deployed, Range Of Functions And Inter Regional Co- Operation (Event Management Only)......................................................25 2.5 Scale Of Calls Received.............................................................................26 2.5.1 South Area....................................................................................................26 2.5.2 Central Area.................................................................................................26 2.6 Issues Arising And Recommendations....................................................27 2.6.1 National Level Issues And Recommendations.......................................27 2.6.2 Regional Level Issues and Recommendations........................................27 2.6.3 South Area Issues And Recommendations..............................................28 2.6.4 Central Area Issues And Recommendations...........................................29 3. Flood Forecasting...................................................................................................31 3.1 Overview Of Flood Forecasting And Weather Monitoring..................31 3.2 Weather forecasting...................................................................................31 3.2.1 Availability Of Weather Forecasts.......;................................................... 31 3.2.2 Accuracy Of Weather Forecasts................................................................32 3.3 Agency Telemetry Outstation Availability And Robustness................34 3.3.1 South Area....................................................................................................34 3.3.2 Central Area.................................................................................................45 3.4 Ability Of Agency To Predict The Actual Flood Levels Using Their Current Models (Predicted Vs. Actual Levels).....................................................46 3.4.1 South Area forecasting............................................................................... 46 3.4.2 Central Area forecasting............................................................................48 3.5 Impact Of Any Inaccurate Flood Forecast...............................................50 3.6 Issues Arising And Recommendations....................................................51 4. Flood Warning.........................................................................................................53 4.1 Overview of Flood Warning in the Region..............................................53 4.1.1 Flood Warning Areas in North West Region..........................................53 4.1.2 Impact of new 4 stage Warning system...................................................53 4.2 Trigger/Threshold levels for Warnings....................................................53 4.3 Warnings Issued, Target Lead Times Versus Actual Lead Times....... 61 4.3.1 South Area....................................................................................................61 4.3.2 Central Area.................................. 62 ~Floods TT Report.v3.8.doc datedj 05 Apnl■, 2001 17 ENVIRONMENT AGENCY 089314 Floods Report October/Novcmber 2000 Environment Agency North West 4.4 Summary of Warnings and Severe Flood Warning across the Region. 63 4.5 Use And Effectiveness Of Warning Systems...........................................79 4.5.1 Use of AVM ................................................................................................. 79 4.5.2 Floodline, Flood Wardens, Local Media, Sirens, Public Address........80 4.6 Extent Of Flooding.......................................................................................80 4.7 Issues Arising And Recommendations.....................................................81 5. Event Im pact............................................................................................................83 5.1 Overview Of Weather Conditions.............................................................83 5.2 Overview of flooding in the Country/Region..........................................91 5.3 River levels....................................................................................................91 5.3.1 South Area.....................................................................................................92 5.3.2 Central A rea..................................................................................................92 5.4 Flooding - Source of flooding.................................................................. 93 5.4.1 South Area.....................................................................................................98 5.4.2 Central Area............................................................................................... 106 5.5 Number Of Properties Not Flooded Due To Agency And Third Party Defences.......................................................................................................I ll 5.5.1 South Area...................................................................................................I ll 5.5.2 Central Area................................................................................................I ll 5.6 Number of Properties Flooded due to Failure (Not Exceedance) of Agency and Third Party Defences.................................................................................112 5.6.1 South Area...................................................................................................112 5.6.2 Central Area................................................................................................112 5.7 Number Of Properties Flooded Due To Exceedence Of Agency Defence Standards.....................................................................................................112 5.7.1 South Area...................................................................................................112 5.7.2 Central Area................................................................................................112 5.8 Towns Without Adequate Defences.......................................................113 5.9 Incidence Of Repeat Flooding................................................................113 5.10 Issues Arising And Recommendations.................................................. 113 6. Emergency Response...........................................................................................115 6.1 Major Incident Plans Activated...............................................................115 6.2 Agency Staffing, Plant, Adequacy Of Resource, Range Of Functions, Inter Regional Co-Operation.............................................................................115 6.2.1 South Area...................................................................................................115 6.2.2 Central Area................................................................................................116 6.2.3 North Area...................................................................................................117