This is the presentation made by the Environment Agency, to the London Borough of Enfield Planning Committee and local residents at Highlands School on Monday July 9th

2. SALMON’S BROOK
FLOOD ALLEVIATION SCHEME
Planning Panel
9th July 2012
Highlands School, Grange Park, Enfield

3. Presentation team
Graham Cowell (Environment Agency)
Steve Whipp (Environment Agency)
Mike Gara (Environment Agency)
Roland Grzybek (Halcrow)
Windsor Young (Volker Stevin
Mike Ferens (MMA)

4. Flooding in Enfield
• Enfield has a history of flooding
• Most recently in October 2000
• 192 properties flooded
• Approximately 2000 properties at
risk
• 5% chance of flooding in any year Flooding, October 2000
Flooding in Granville Road, October 2000

5. Flood Alleviation Scheme Objectives
Reduce the risk of flooding to 1393 properties
(2587 households), of which 727 properties will
be protected from a 1.3% (1 in 75) AEP flood.
Reduce the risk of flooding from Saddlers Mill
stream coming up through the manholes in
Montagu Road.
Provide environmental and amenity
enhancements to the area as part of the works.
Benefit – cost ratio of 6.2 for a 1.3% standard of
protection.
Aim to start construction in 2012/13

6. Flood Alleviation Scheme Elements
Saddlers Mill
Flood Storage at
Stream
Boundary Ditch
Enfield Golf Course
Raised defences
Sandhurst
Road &
Falcon
along Salmons Walk
Fields
Enfield Golf Course &
New culvert route
Cheyne Walk Open
Space under Montagu Road
Montagu Flood Storage at
Road
Recreation
Ground
Montagu Road
Salmons Walk
Recreation Ground &
Salmons environmental
Brook
improvements
Localised Measures
Montagu
Road to address Saddlers
Mill stream

7. Flood Maps Pre & Post Scheme –
Edmonton 1 in 75

8. Flood Maps Pre & Post Scheme –
Saddlers Mill stream area 1 in 75

9. Flood Maps Pre & Post Scheme –
Montagu Road Area 1 in 75

10. Enfield Golf Course
Enfield Golf Flood embankment
Club
Cheyne Walk
Allotments Open Space
Access tracks
Store flood water temporarily
Provide an environmentally sensitive design
Mitigate any impacts on the Golf Course
Provide a structure that is safe to operate with minimal maintenance
Conform to the Statutory Reservoirs Act 1975
No increase in flood risk to those properties upstream of the structure

11. Enfield Golf Course
What the proposed flood embankment will look like at Cheyne Walk Open Space
What the proposed flood embankment will look like at Enfield Golf Course

12. Montagu Road Area
Montagu Road Recreation Ground,
environmental improvements
amenity creation & new flood
storage
Montagu Road, new culvert route
Salmons Walk, raised defences
along walk

13. Salmons Walk
Require raised
defences along
Salmons Walk -
approx 1m x 550m
both banks
Provide the
appropriate
environmental
enhancements
Enhance the path to
a combined footpath
and cycleway
An artist’s impression of Salmons Walk after the scheme – looking towards
standard.
Montagu Road

14. Montagu Road Recreation Ground
Store flood water
New paths Shaped river temporarily
banks
Provide
Concrete
removed
environmental
Pavilion enhancements to the
New open
watercourse and
channel surrounding area in a
restored river setting
New fixed
New trees
structures to Meet the current
control water
needs of users of the
Football
Pitch Raised ground and
open space Conform
Existing
new shrubs to the Statutory
flood New Reservoirs Act 1975
storage embankments

15. Montagu Road Recreation Ground
An artist’s impressions of
Montagu Road Recreation
Ground after the scheme
<< Looking towards Zambezi
Drive from near the pavilion
Looking south
from near the
pavilion >>

16. Construction Access – Enfield Golf
Course – proposed route
Constraints
Open space access
via Uplands way
Cheyne walk would
require car parking
restrictions along its
whole length
Pinch points –
vehicles unable to
exit safely at Landra
Gardens due to
traffic restrictions
(bollards etc)
School hours

17. Construction Access – Salmons Walk
– proposed route
Constraints
Linear site –
access required
at both ends.
Only entrances
to Salmons
Walk.
Limited access
from Plevena
Road
Main access
Montagu road

18. Construction Access – Bury Street
West – proposed route

19. Access during construction – Enfield
Golf Course & Cheyne Walk Open
Space
Golf course will remain open with all holes playable -
slightly shortened 9th hole (although localised
improvements within the golf course currently being
considered with EGC may cause more temporary
disruption).
Cheyne Walk
• Pedestrian access at all times to allotments and
open space.
• Vehicular access available at evenings and
weekends. Vehicular by arrangement with contractor
in special circumstances during working hours.
Deliveries ok by arrangement
Barnabas Court – pedestrian access and vehicular
access all times.

20. Access during construction –
Salmons Walk
Due to our legal health and safety obligations for a
working construction site to protect members of the
public we cannot allow access during the works.
We will sign an alternative route. e.g. Cemetery
Walk and local roads.
Post scheme – Salmons Walk will be provided with
a new combined cycleway and footpath.

21. Access during construction –
Montagu Road
Access to current play areas, community centre and
sports field will be maintained during the works.
The minimum space possible will be occupied on the
recreation ground to allow access to the open space
during construction.
Temporary traffic lights will be required while the culvert
is constructed on the edge of Montagu Road
To deliver materials to Salmons Walk there will be some
construction traffic across Montagu Road.

22. Access during construction – Bury
Street West
Site currently closed to general public – no change in
access
No impact on Enfield Council depot for day to day
operations
Works are very small-scale localised in-channel works.
Construction duration estimated at a few weeks.

23. Planned Extent and duration of the
works
Enfield Golf Course and Cheyne Walk
Site set up and utilities diversions – 5 months
Flume structure – 5 months
Delivery clay – 3.5 months
Embankment construction – 3.5 months
Landscaping & finishing – 3.5 months
Grass seeing – 1 month

24. Planned Extent and duration of the
works
Salmons Walk
Site set up and surveys – 1 month
Flood defence wall right bank d/s – 11 months
Flood defence wall left bank d/s – 11 months
Sheet piling – 3 months

25. Planned Extent and duration of the
works
Montagu Road
Montagu Road culvert – 7 months
Earth embankment – 6 months
Landscaping – 1 month

26. Construction noise and disturbance
General
Works will use construction best practice for which we have won
numerous construction awards.
We will operate under the Considerate Contractors Scheme – audited by
an independent body.
We will operate in standard working hours.
We have planned our deliveries outside the rush hour and school run.
We will operate within the requirements for noise levels. Plant and
design has been chosen to minimise disturbance as much as possible.
We will use modern anti-noise anti vibration construction machinery with
appropriate silencing mechanisms.
Condition surveys will be undertaken where required. We do not
envisage that the works and associated site traffic will cause any
structural damage to the properties along the proposed route.

27. These activities from previous projects
have not caused damage to properties

28. Stakeholder consultation to date:
Stakeholder consultation to date includes:
Public exhibitions, 2004, 2008, 2012.
Public newsletters 2004, 2005, 2008, 2011 (council &
MP), 2012
Area Forums 2010, 2012
Presentation Meetings
Cemeteries
Enfield Golf Club
Enfield Council

29. Communication during construction
Dedicated community liaison officer
Local residents forum
Local schools engagement
24 hour hot line
Regular progress update

30. Flood Alleviation Scheme Benefits
Best opportunity to reduce flood risk in the Lower Lee
valley.
Included by defra in their funding announcement for flood
alleviation schemes for the last 2 years.
Reduce the risk of flooding to 1393 properties (2587
households), of which 727 properties will be protected from
a 1.3% (1 in 75) AEP flood.
Reduce the risk of flood water from Saddlers Mill Stream
coming up through the manholes in Montagu Road and in to
properties.
Provide bio-diversity, habitat creation and amenity
enhancements to the area as part of the works.
Prevent £156.2 million of damage in the 1.3% chance flood
event.

31. Questions?
Steve Whipp, Environment Agency, Senior User – Client
Mike Gara, Environment Agency, Project Manager
salmonsfas@environment-agency.gov.uk.