2012 Flood Investigations North Somerset – 2012 Flood Investigations
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North Somerset - 2012 Flood Investigations North Somerset – 2012 Flood Investigations Table of Contents Table of Contents ...................................................................................................... i 1 Introduction ....................................................................................................... 1 2 Key Responsibilities ......................................................................................... 3 3 Rainfall in 2012 .................................................................................................. 6 4 Flood Incident Extent and Impact .................................................................. 16 5 Abbots Leigh and Pill & Easton-in-Gordano................................................ 19 6 Backwell........................................................................................................... 21 7 Banwell............................................................................................................. 23 8 Blagdon ............................................................................................................ 26 9 Churchill and Langford ................................................................................... 29 10 Claverham and Yatton................................................................................. 34 11 Clevedon....................................................................................................... 40 12 Congresbury ................................................................................................ 43 13 Dundry and Winford .................................................................................... 48 14 Hutton ........................................................................................................... 51 15 Locking ......................................................................................................... 53 16 Nailsea .......................................................................................................... 57 17 Portbury........................................................................................................ 62 18 Portishead .................................................................................................... 67 19 Weston-super-Mare ..................................................................................... 70 20 Winscombe & Sandford .............................................................................. 76 21 Wraxall & Failand......................................................................................... 79 22 Wrington ....................................................................................................... 81 23 Remaining Investigations ........................................................................... 87 24 Summary - Risk Management Authorities ................................................. 92 Glossary .................................................................................................................. 93 i North Somerset – 2012 Flood Investigations 1 Introduction In 2012, unprecedented levels of rainfall were experienced throughout England causing wide spread flooding. The Met Office reported that 2012 was the wettest year on record in England and the second wettest in the UK since records began. Furthermore North Somerset experienced more rainfall than the national average. The most severe storm events that occurred in North Somerset were in August, September and November impacting both residential properties and businesses alike. All Risk Management Authorities (RMAs) have responsibilities for flooding from different sources (Table 2). Historically it had not been easy to identify which RMA had a duty to investigate flood incidents and carry out their flood risk management functions. This is because there is often a multitude of flood sources, some of which are not easily identifiable once the water has dissipated. Under new legislation1 North Somerset Council has a responsibility to investigate flood incidents where it is considered appropriate. The purpose of this report is to investigate the flooding that occurred across North Somerset in 2012, identifying what the main causes of flooding were and which RMAs have appropriate risk management functions. This does not necessarily mean that any RMA will be undertaking physical works, but will ensure there is a clear understanding of which RMAs have risk management responsibilities in relation to any flood incident. Intelligence was gathered from residents, professional partners, Parish / Town Councils, local community groups as well as others to inform our investigation. This information was compiled to make a list of flooded properties and investigate the cause of the flooding. One of the difficulties experienced during investigation was obtaining useable information and it was quickly recognised that local residents were often the best source of intelligence and capturing their knowledge was an important process. This information gathering exercise included Local Community Flood Surgeries, flood report forms and site visits amongst other activities. To ensure the full extent of the flooding is appreciated and recorded it has been decided that this report will include all locations, brought to our attention, which experienced any internal property flooding and also other areas of particular concern. 1 Flood and Water Management Act 2010 1 North Somerset – 2012 Flood Investigations 1.1 Flood and Water Management Act 2010 The Flood and Water Management Act 2010 (the Act) was established in April 2010 and defined unitary authorities and county councils as Lead Local Flood Authorities (LLFAs). Section 19 of the Act commenced in April 2011 and gives LLFAs the duty to investigate flooding when considered appropriate and publish the results. Flood and Water Management Act 2010 Section 19 – Local authorities: investigations This flood investigation report has been produced by North Somerset Council (NSC) as a Lead Local Flood Authority under Section 19 of the Flood and Water Management Act 2010: 1) On becoming aware of a flood in its area, a lead local flood authority must, to the extent that it considers it necessary or appropriate, investigate - a) which risk management authorities have relevant flood risk management functions, and b) whether each of those risk management authorities has exercised, or is proposing to exercise, those functions in response to the flood. 2) Where an authority carries out an investigation under subsection (1) it must - a) publish the results of its investigation, and b) notify any relevant risk management authorities. Flood and Water Management Act (2010), S.19, c.29, London: HMSO A ‘Risk Management Authority’ (RMA) means: (a) the Environment Agency, (b) a lead local flood authority, (c) a district council for an area for which there is no unitary authority, (d) an internal drainage board, (e) a water company, and (f) a highway authority. When considering if it is necessary or appropriate to investigate a flood incident NSC will review the severity such as the number of properties affected and the frequency of such an occurrence. Currently NSC is working to the following thresholds: five or more residential properties flooded internally; two or more non-residential properties flooded internally; one or more critical service (e.g. hospital) flooded, and/or; a key transport link is totally impassable for a significant period. As no flood incident is the same, it is not feasible to cover all possible thresholds; therefore there may be circumstances where North Somerset Council may choose to carry out an investigation where the above is not met. 2 North Somerset – 2012 Flood Investigations 2 Key Responsibilities 2.1 Recording Flood Incidents For the LLFA to carry out a flood investigation efficiently, it is necessary to record the flood incidents that occur across North Somerset. To help gather intelligence effectively and consistently, a Flood Report Form was created. Information is shared between RMAs to ensure a more representative picture is captured. Table 1 summarises the type of information collected from the report form. The following information will be recorded on a flood incident database, supporting NSC carry out its flood investigation duties from December 2011 Start date Duration Main source Fluvial (watercourse); Surface water runoff; Drainage structure defect; Tidal; or Groundwater Main characteristics Natural flood; Flash flood; or Debris flow Clear; Muddy; or Polluted Extent Internal / External property flooding; Depth; & Highway impact Historic flooding Table 1: Information the LLFA now records 3 North Somerset – 2012 Flood Investigations 2.2 Risk Management Authority Responsibilities There are various other Risk Management Authorities in addition to North Somerset Council, all who have their roles and responsibilities. Table 2 specifies the functions of each Risk Management Authority and the different sources of flooding for which they have a risk management function. Lead Local Internal Environment Highways Wessex Flood Source Flood Drainage Agency Water Authority Authority Board The Sea Main River 2 Ordinary (if located Watercourse 3 in IDB area) Surface Water Surface Water highway flooding Groundwater Sewer Flooding Reservoir Table 2: The different RMA’s responsibilities for managing flood risk from different sources and enforcement North Somerset Council as the Lead Local Flood Authority