Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

London Flood Risk Management Strategy Adam Hosking

Presentation from NY/NJ Metropolitan Storm Surge Working Group Conference, May 18, 2017

  • Login to see the comments

  • Be the first to like this

London Flood Risk Management Strategy Adam Hosking

  1. 1. Thames  Estuary  2100   London’s  Flood  Risk  Management  Strategy Presented  by   Adam  Hosking   Practice  Director  Water  Resources  &  Ecosystem  Management,  CH2M
  2. 2. 2 Overview • The  UK  Strategic  Approach • TE2100  – The  Strategy • TEAM2100  -­‐ Implementation
  3. 3. 3 • Watershed  &  Coastal  Cell  Plans • Large  scale – Physical  systems  &  driving  forces – Integrated  response  and  planning • Long  term  view – Climate  change – Sustainable  approaches – Whole  life  costs UK  Strategic  Flood  Risk  Management  Framework
  4. 4. 4 North  Sea The  Thames  Estuary  2100  Strategy
  5. 5. 5 Thames  Estuary  2100 Why? Provide  continued  protection  for  1.25  million  people  and  £200  billion  worth  of   property  from  tidal  flood  risk  on  the  River  Thames,  over  the  next  Century.
  6. 6. 6 TEA-ZZ-ZZ.ZZ-TP-PM-ZZ-000005 ISSUE DATE: 07/08/2015 UNCONTROLLED WHEN PRINTED 6
  7. 7. 7 • Over  4000  Assets • 9  Major  Barriers • 350km  linear  defences • 300+  active  structures TE2100  – Protection  System
  8. 8. 8 The  Thames  Barrier
  9. 9. Thames Barrier,  UK         • Operational  since  1982 • 520  meters  long • 10    gates  :  4  navigable    61  meters   rising  sector  gates,  weighing  3,300   tonnes;  2  No.  31.5m  wide  RSG  plus   4No.  31.5m  falling  radial  gates • Gates  are  filled  with  water  when   submerged  and  empty  as  they   emerge  from  the  river • Cost:  £534  million  (£1.3  billion  at   2001  prices) • Level  of  protection:  1  in  1,000  year  
  10. 10. 10 Major  Barriers Largest  Programme  Since  Original  Construction
  11. 11. 11 Other  Asset  Types
  12. 12. 12 Climate  change  scenarios   Increases  in  peak  1000-­year  surge  tide  level  and  sea  level  rise  component 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 2000 2020 2040 2060 2080 2100 2120 Date Sea  level  (m  AOD)  at  Southend Medium  High  SL  rise Medium  High  total High  ++  SL  rise High  ++  total Defra  SL  rise Defra  total  (=  SL  rise) High  +  SL  rise High  +  total Latest  DEFRA    SL  rise Increases  in  peak  1000-­year  levels  at  Southend  under  5  different   climate  change  scenarios TE2100  Climate  Change  Scenarios
  13. 13. 13 Freeboard:  Standards  of  Protection
  14. 14. 14 • Four  approaches  (High  Level  Options)  to  manage  water  levels   through  the  century: – Traditional  Engineering  (HLO  1)   – Floodplain  Storage  (HLO  2)   – New  Barrier  (with/without  Thames  Barrier)  (HLO  3)     – New  Barrage  (HLO  4)   • The  limits  to  adaptation  study  identified  the  thresholds  at  which   each  option  would  no  longer  provide  an  adequate  standard  of   protection  to  London Estuary-­‐Wide  Planning  for  an  Uncertain  Future
  15. 15. 15 Feasibility  of  Raising  the  Existing  Defenses  
  16. 16. 16 Feasibility  of  New  Defenses
  17. 17. 17 17TEA-ZZ-ZZ.ZZ-TP-PM-ZZ-000005 ISSUE DATE: 07/08/2015 UNCONTROLLED WHEN PRINTED Geomorphology  – Impacts  on  Flood  Protection
  18. 18. 18 Assessment  of  Managed  Re-­‐Alignment  Sites
  19. 19. 19 1m0m 4m3m2m Max  water  level  rise: New    barrier,  retain  Thames  Barrier,  raise  defences Raise   Defences New    barrier,  raise  defences New    barrage HLO  1 HLO  3a HLO  3b HLO  4 HLO  2 The  plan  considered  a  combination  of  approaches Existing  system Improve  Thames  Barrier  and  raise  d/s  defences   Over-­rotate  Thames   Barrier  and  restore   interim  defences Flood  storage,  improve  Thames   Barrier,    raise  u/s  &  d/s  defences Flood  storage,  over  rotate  Thames   Barrier,  raise  u/s  &  d/s  defences Flood  storage,  restore   interim  defences TE2100  H++Defra UKCIP  MH TE2100  H+
  20. 20. 20 Strategy  Findings • With  an  adaptable  plan  rising  water  levels  can  be  managed   through  this  century  and  into  the  next • Continue  to  maintain/improve  existing  FRM  structures  – barriers,  gates,  levees   • Spatial  and  emergency  planning  essential  part  of  future  FRM • New  inter-­tidal  habitats  before  2030  to  offset  SLR  impacts • The  Thames  Barrier  should  continue  to  provide  protection towards  the  end  of  the  21st century • Barriers  and/or  barrage  are  essential  under  all  future  scenarios   to  manage  surges  and  SLR  
  21. 21. 21 Thames  Estuary  Asset  Management  2100  (TEAM2100) • CH2M  appointed  as  Delivery  Partner • Top  40  UK  Government  Major  Project • At  £300  million  -­‐ the  Environment  Agency’s  largest  single  flood   risk  programme • Efficiency  target  of  £100  million  over  10  years
  22. 22. 22 TEAM2100 Work  Scope  – 10  year   programme: • Asset  Management • Asset  Investigations • Appraisal • Detailed  Design • Construction • Programme  Management  and   Scheme  Optimisation • Programme  Controls • Partnership  Funding To  Deliver: • Improved  Asset  Management  – ISO55000 • Reduced  Flood  Risk • Integrated  Solutions • Great  Efficiencies • Lessons/Best  Practice  for  Future   FCRM  Delivery
  23. 23. 23 Estuary  Wide  Asset  Management  Approaches TEAM2100
  24. 24. 24 TEAM2100 AM  Approaches  – Asset  Investigations 3D  Scene  from  UAV  Imagery
  25. 25. 25 • Whole  Life  Cost  and  Deterioration  Modelling • Sensors  creating  a  smart  estuary TEAM2100 AM  Approaches  – Whole  Life  Approach
  26. 26. 26 Cost-­‐effectiveness:  Investment  Scenarios
  27. 27. 27 Foreshore  erosion  forming   cavity  under  wall AM  Approaches  – Monitoring  Duke  Shore  Wharf -­‐ Mass  concrete  wall  undermined  by  foreshore  erosion
  28. 28. 28 Asset  Monitoring
  29. 29. 29 …  and  repair!
  30. 30. Operatives  removing  silt  from   gate  Alpha  leaf  cell  A. Operatives  require  ear   defenders  &  protective  clothing. Heavy  silt  material   on  floor  of  gate  leaf   removed  using  jet   wash.
  31. 31. 31 Thames  Barrier Principal  Inspections  – 3D  Scanning
  32. 32. 32
  33. 33. 33 TEAM2100 Status • Achieved  ISO55000  AM  Accreditation • Whole  life  cost  modelling  to  change  estuary  asset   management  approach  -­‐ £1000m  WLC  saving? • £50m  savings  identified  on  large  realignment  schemes,   accelerate  schemes • £33m  programme  in  2017 • £15m  efficiency  savings  in  2017
  34. 34. Thank  You Any  Questions?   Adam.Hosking@CH2M.com
  35. 35. 35
  36. 36. 36 Thames  Barrier  Closures https://www.gov.uk/guidance/the-­‐thames-­‐barrier
  37. 37. 37 Risk  Management   TEA-ZZ-ZZ.ZZ-TP-PM-ZZ-000005 ISSUE DATE: 07/08/2015 UNCONTROLLED WHEN PRINTED 37
  38. 38. 38 ~  £1.4  bn ~  £1.5  bn ~  £6  -­‐ 7  bn First 25  years   2010  – 2035   Continuing  investment  and  planning   together Middle 15  years From  2035  to  2050 Renewal  and  reshaping  the  riverside To  the end  of  the  century From  2050 Moving  towards  the  22nd century   The  Strategy

×