Local flood risk management strategy www.portsmouth.gov.uk 2 • Local flood risk management strategy Foreword This document has been prepared with the work in the city aimed at reducing flood residents, businesses and visitors of risk to properties from surface water, and Portsmouth in mind. we will shortly be investigating levels of groundwater around the city to determine Working from guidance given in recent whether or not this will be an increasing government legislation (The Flood and Water problem in the future. Management Act 2010) this strategy sets out for the first time how Portsmouth City This is an exciting time for Portsmouth and Council works with the Environment Agency, we cannot afford to be complacent. The neighbouring local authorities, emergency council will ensure the work we do takes into services and water companies to reduce flood account all the existing plans we have for the risk in the city. city and we will maximise any opportunity that allows us to work with other Our flooding problems are quite clearly organisations both public and private, so we defined, we have no real issues associated have a safe environment to live and work in with either main river or ordinary watercourse, both now and in the future. and we focus our attention on coastal flood risk, surface water and groundwater. Whilst flooding can never be fully eliminated, I believe this document sets out our plans for The strategy sets out to explain these different the reduction of flood risk and how we are types of flooding and how we are working to working in a co-ordinated approach with our reduce the risk from them. This work will partners and stakeholders to provide the encourage regeneration and bring inward greatest levels of flood protection possible for investment to the city as flood defences and the city. drainage networks are improved. Our strategy focuses on flood risk on a ward by ward basis. It identifies known flooding problems and how we are dealing with them along with on-going issues where we are working to find a solution. Gerald Vernon-Jackson We are already gaining momentum for Leader, Portsmouth City Council refurbishment of the sea defences at Southsea and North Portsea Island, and have begun to look at how this should be done. Southern Water is also undertaking major Foreword • Local flood risk management strategy • 3 Contents Introduction 6 Historic flooding in Portsmouth 9 Location 10 Flood risk in Portsmouth 12 Interactions between different types of flooding 21 Climate change 22 Citywide flood risk measures 24 4 • Local flood risk management strategy • Contents Flood risk ward by ward 35 Protecting individual residential properties and flood insurance 64 Action plans 66 What you can do to minimise the effects of flooding 72 References 73 Glossary of terms 74 Contents • Local flood risk management strategy • 5 Introduction Flooding is one of the biggest natural challenges facing Portsmouth. Our position as a coastal city brings great benefits and these are reflected in the council’s goal to shape the great waterfront city. However, the risk of flooding from the sea, along with that from surface water, are significant issues facing the city due to their potential to threaten people, property and the environment. This risk will increase as a result of climate change. Whilst we cannot entirely eliminate the risk of flooding, this strategy aims to locally manage flood risk for the people, economy and environment of Portsmouth. Why has the strategy been written? As a unitary authority, Portsmouth City Council is designated as a Lead Local Flood Authority (LLFA) under the Flood and Water Management Act 2010 (the ‘act’). The act places a statutory duty on LLFA’s to develop, maintain, implement and monitor a Local Flood Risk Management Strategy (hereafter referred to as the ‘strategy’) to manage local flood risk in its area. The strategy aims to locally manage flood risk for the people, economy and environment of Portsmouth by working in partnership to identify and deliver feasible and timely actions. What are the guiding principles behind the strategy? The strategy is focused on the following principles as set out in the ‘National Flood and Coastal Erosion Risk Management Strategy (NFCERM)’ with which our local strategy must be consistent. • Community focus and partnership working • Catchment and coastal cell based approach • Sustainability • Proportionate, risk-based approaches • Multiple benefits • Beneficiaries should be allowed and encouraged to invest in local flood risk management 6 • Local flood risk management strategy • Introduction PORTSDOWN ROAD R G AVENUE J BROWNIN B A C U L R S D Y H E B K O H R I M A I W E T E L Y U A H L E O S N D C L T E U N I A E E N E S L A D V N Y R G L A V E R O W L A I N R A D A A V A R E D V N O V V V V E N A U E N E A E E U N E N N N U D E C U U U E L E E E O S E WORDSWORTH AVENUE NNAUGHT L ANE CO H SEDGEFIELD CLOSE C I O L MASEFIELD AVENUE M L L C 2 S E P A M O E 7 L I R A D L E V A I T E D S G C M E R E . N R A E O D MACAULAY AVENUE W A A D B L K O L I N A L T G W T R U R O D S A R R A O C O Y O A A BRIDGES AVEN T D UE T V E M H E R E O N O E U UE A D S D G E E H H S O O N R E E V H L A E B E R A O C A FALMOUTH ROA H D © Crown Copyright and database right 2013. Ordnance Survey licence number 100019671. H B D I U D L L D R S I E L V E C E Y L R . N O A E S D W O B PE U N D E N O IS T RO A D L H A T F A A L R L M M A O M L A O O P L D T U N A O T H D W N R S A O B R Y A U O D A R A V Y D E R N O U A E D BA TH S Q Paulsgrove B B R E O V A E D R S S E T T O R A E S N E T T R D O S W E A I C CH K E T H D E A D M W R S R T O E D R H E E T U E B H T R R U H S C T H U A V T T A T R N R T H S E J T S E R E C R E A T E T S H R F M C A C L E R R Y P E E E D S O S C N S C O D C R H A W T W E E K R E C T H L S I T T N E N L H I A A T R W T V E RO T A L G D E ADMIRALTY R A L E A O Y S A M G D T 2 H R 7 H A N O V A E R S E T AD E N O RF R T HA D GUNW B U L T R O C H M I E W O O F F E R T O N A R O D B R V A S R T E R D E S E T T R Charles Dickens E T E TREE S S C A S T CRO S U R C T M T M O B H B L W K I O O E E R H H I R M I R D A N OA S R D P IG G HOWE Y ON L B H R RZ E A CU G H L A B B L N S O I U S A L W N N ’ P T S R U I Y N R N D Y K I R Q R E S G L S T E E N E O T B U L S T T R N I R O T A E I E S T T A E S A R N D T E I R E T M G N ET RE E S T R OP ST N S S BISH O T E E T E T L E C M A N S L O S R T E P E R N I T T D E R T E E O St Thomas M T A G R E E R R C T E S E E S T A E P S O T ’ T T S E E T N E U G C H G T R P L T T M I K N E C S R O T O R A E O E T H L N L B N A R O R S P A E O A E G O R L D T G I N K V E L L R A O E K C S E T S R ’ W E S U S W K W S W T R O W O E T I O A B T R A R N A Y A Y N A R E O T C Y E I E D H H O N T U R R C A S R T R O JAM T O O ES’S S D D CE A A M YORK PL N A D D E B E R R O B O A E L A E D D C O K B U N R N A B Y S R O A D M C T I A A P MB N R L V I R D M A H T A H C S IE E I R D L G T H R E A O R E E A V W O R D I M A L E L I D V D R O I O V A M C W E R P T D Y O S O U P S A A R T AD E V I R E A U D K E S C M N O A R O R V U U O R O L O E E A T L N A H I A D N D U BLOUNT R OA D A G E D M T P O T N O M S O C R B T O N IM E E R L R R U L O AD D R E E T U V LA O S N D H DPO GLESEY ROA I U R N T A C S T A E ER S R A B CE E D E U T C N ERR OM L AC PA A R E S U T S T R D I G A P D N E T L R W L L E F H LA A O N W R N A DS R D O W E E A Y NE W G K L S R TREE H E D T M E I D O I D A W R R T N S ’ D L R U F A P L IN T O S O E C C T I B L S O O TR EE A T I G N B E D A D L E S R A C R D U T B I W O H D L M S S U R P E A O Y T H R L I N N N M K I P G R R 2 R 7 O G A 5 S R H E Y A D R T O T I R O S U DE K A R S A S C AR TO P N N N E N S T R O TR L TE E T S E E I E T D W C S R A M R R A O C E O O T R A E Y R E T S E D H A N E G S E T D O L E L N U A B R IE E T T I D O R L M A C R O D A R C R K B E U W H R B A W K K H D E A B R E E O C I L I S T H L A T I N E S N N S N W L U W L H A P N Y I A G S G H T D T O IN E A R O GALE R S LK L O A L R D A Y D L E T P G S E P A R E S W A E T O S E O C U O O TH E E S L S N T EA N ST E K I A M A N R Q R S R T A Y I V B N E C L U E K S O D C E T U I A E R L A S E E D O A I L N A R R S H T E S H R N T A S E A TIPNER LANE E F T T N E L S R BU R O R D U Y Nelson O R H L OA G E D D A E R E A D S C S S C C W D A T T M I R D S E L S D H S T R E E E A T T R U O St Jude L I S C O O Y L S E K M A T M T E S E L R E S T R E S L E R N D O E C A D I S A C H O E L B L R UR N R E D T A ON A E A D R X O N C A D D T V D E E N H W R E H R I W T F P A I L E R A L L N D O G T A H L O E B O E T S R U Y L R R S O E R A R U A O R O R O A T O D O A C A A D D D D E E E U D D A H H S N D S O T U E L A P P S T H J A M P H E S ’ S T R H O E A I D N R C S R M E E TON I W N A C O K E S L S P RO A T B K T T L O N M A I D A R R C A A U B I T E D E R W L B K N K T N E R R T S R R U O L E T I G A E T R Y O D O O L D A T A R R T O S U Y W A S L N C A O K R G D G RB E T O A O G O T R O D Q R W R E O O R A A E R N R U D S U G D E H W M E H Y W A L E R E I U D O P E R N T L A N O D E R O T A N D A A E S A O S H D B E Y D W J W R E N N E R P B S C R O M T MILE E R E O N R A S K R A D M E W A R C E T R E R R O O P D O E N I C A A N R O A D O L S V S A E E W A W A E L D B D R O D N D T E C Y S I T E L S M A M O T I D D E E S S E I N X R E L T R T R L G E L C S S L S R E A N A Y E R E S S B I G M R T C R E B E R R O N C S T W V A C Y S T N E M O O N Y E E O R I E R E E E O L R O O S C R K O E T L E E R L T A A R R N N E R N E E O A P M R A R A E D S L N E N N