Local Flood Risk
Management Strategy
London Borough of Tower Hamlets
Contents
i.
Definition of terms
1. Introduction
2. Legislative Context
2.1
Background
2.2
Flood and Water Management Act 2010, section 9.
3. Flood Risk Assessment
4. Investigation of Flood Risk
4.1
Surface Water Management Plan
4.2
Initial Critical Drainage Areas
4.3
Revised Critical Drainage Areas
5. Mitigation of Flood Risk
5.1
Gullies: Our first line of defence
5.2
In Critical Drainage Areas
5.3
Sustainable urban Drainage Systems
5.4
Tower Hamlets SuDS Guidance
5.5
Changes to Surface Water planning Advice
6. Partners in flood risk mitigation
6.1
Tower Hamlets Council
6.2
Neighbouring boroughs
6.3
Transport for London
6.4
Statutory Undertakers
6.5
Environment Agency
6.6
Canals and Rivers Trust
6.7
Thames Water
6.8
Private sector and Housing Associations
7. Registers and Records
7.1
Flood Incident Register
7.2
Asset Register
8. References
9. Review
10. Revisions
Definition of terms
Flood
Risk
Flood Risk
Risk Management
Lead Local Flood
Authority
Highway Authority
Flood Risk
Management
Authority
Surface water runoff
Groundwater
Ordinary Watercourse
Land that is not normally covered by water becomes
covered by water, this does not include a flood from a
sewerage system unless sewerage volume increased by
precipitation or a flood caused by a burst water main [1]
Assessment of the probability and occurrence of an event,
assessed with its potential consequence
A risk in respect to a flood
Includes anything done for the purpose of analysing,
assessing or reducing a risk
The authority for flooding in the area, in this case the London
Borough of Tower Hamlets
As described in Section 1 of the Highways Act (1980) [2]
An authority such as the Environment Agency or the Lead
Local Flood Authority that have a statutory responsibility to
manage flood risk under the Flood and Water Management
Act (2010)
Any form of precipitation that is on the ground and has not
entered a watercourse or drainage system
A watercourse that does not form part of a main river
1.0 Introduction
The Local Flood Risk Management Strategy (LFRMS) is designed to provide guidance and
information for residents, businesses and developers regarding Tower Hamlets strategy for dealing
with flooding within the borough. The document is structured to outline the responsibility of the
Lead Local Flood Authority (LLFA), evaluate the risk of flooding and finally review and appraise
methods for dealing with flooding in LBTH.
The document begins with the legislative context for the writing of this strategy so as to describe
the duties of LBTH in this regard as Lead Local Flood Authority.
It continues with an explanation of our work to assess the potential risk of flooding and it shows
how both the Preliminary Flood Risk Assessment and the Strategic Flood Risk Assessment fit into
this work. This is followed by a description of our work to investigate this further through the
Surface Water Management Plan and then through more detailed borough-wide modelling.
Surface water is tracked through a composite model containing rainfall, land topography, gullies
and sewerage so as to identify the nature, extent and location of predicted flooding. We explain
how initial work had predicted surface water pooling in Critical Drainage Areas (CDA) towards the
middle of our borough and how we later understood that the problem was surcharging dirty water
mainly in the Isle of Dogs.
The strategy proceeds, in Section 5, to outline the ways in which, the impact of flooding may be
mitigated. It covers the essential role gullies play as the first line of defence and continues with an
explanation of the measures that we are taking to protect property in CDAs from the predicted
flooding by dirty water arising from an overload of the broader sewer network. This is followed by
an overview of the valuable contribution that SuDS can make to prevent flooding, together with a
link to our SuDS Guidance document.
The LFRMS continues with a description of the work being carried out with Council colleagues
inside the council, partners in other London boroughs, other public sector bodies and the work we
plan with private sector developers and property owners. It concludes with information about the
Council’s Flood incident register and asset register.
2.0 Legislative Context
2.1 Background
The summer floods of 2007 put flooding at the top of the environmental agenda in northern and central
England thousands of homes were flooded, critical infrastructure damaged and unfortunately life was lost.
The economic repercussions were said to cost around £ 4 billion [3].
In response to the summer 2007 floods, central Government commissioned Sir Michael Pitt to produce a
document on the lessons learnt from the 2007 summer floods. In this report 92 recommendations were
made, including 15 urgent recommendations. Prior to 2007 the primary focus of flood risk fell on river and
coastal flooding, with surface water not perceived as high risk source of flooding. After 2007 this changed.
In 2009, the Flood Risk Regulations were published. The regulations are designed to aid in implementing
the requirements of the European Flood Directive 2007, which aims to provide a consistent approach to
flood risk management across Europe. The approach is based on a six year cycle of planning and includes
the development of Preliminary Flood Risk Assessment and also Flood Risk Management Plans. The
Environment Agency, and Natural Resources Wales also need to prepare Flood Risk Management Plans ,
for main rivers the sea and reservoirs covering the whole of England and Wales. LBTH has opted to
prepare a FRMP jointly with the Environment Agency and to do this we will feed in the actions identified in
this LFRMS.
As part of the Flood Risk Regulations the Environment Agency has a requirement to produce Flood Hazard
and Risk Maps of flooding for England. The Environment Agency has produced updated Flood Maps for
Surface Water which are available on their website http://watermaps.environmentagency.gov.uk/wiyby/wiyby.aspx?topic=ufmfsw#x=357683&y=355134&scale=2.
In 2010, the Flood and Water Management Act (FWMA) came into being. This piece of legislation sets out
the delivery of the recommendation from the Pitt Review and provides a more comprehensive management
of flood risk. The FWMA designated that all upper tier Councils and Unitaries were to become Lead Local
Flood Authorities (LLFA). This means that as the LLFA for its area, Tower Hamlets Council is responsible
for surface water, groundwater and ordinary watercourses, with the Environment Agency responsible for
the River Thames and River Lea and Thames Water Utilities responsible for the sewer network. Within the
FWMA there are many deliverables that LLFAs should complete and comply with, one of which is
producing a Local Flood Risk Management Strategy.
Finally, to complete the picture of water management and legislation governing water management, all of
the above must also feed into the Water Framework Directive (WFD) 2003, in which Member States must
aim to reach good chemical and ecological status in inland and coastal waters by 2015. The WFD is
designed to enhance status and prevent further deterioration of waters, promote the sustainable use of
water and reduce pollution. In relation to Tower Hamlets the main outcome from the WFD is the Thames
River Basin Management Plan (RBMP), which will outline the current and projected ecological status of the
catchment. This work is being undertaken by the Environment Agency and is due to be published in
December 2015, as such the LB Tower Hamlets has no locus in producing the RBMP.
2.2 Flood and Water Management Act 2010, section 9.
Section 9 of the FWMA (2010), states that each Lead Local Flood Authority in England must produce a
document to show how local flood risk will be managed within the area. Below is Section 9 from the FWMA
(2010). Sub section 4 specifies what the strategy must cover.
9. Local flood risk management strategies: England
(1) A lead local flood authority for an area in England must develop, maintain, apply and monitor a strategy
for local flood risk management in its area (“local flood risk management strategy”).
(2) In subsection (1) “local flood risk” means flood risk from—
(a) surface runoff,
(b) groundwater, and
(c) ordinary watercourses.
(3) In subsection (2)(c) the reference to an ordinary watercourse includes a reference to a lake, pond or
other area of water which flows into an ordinary watercourse.
(4) The strategy must specify—
(a) the risk management authorities in the authority’s area,
(b) the flood and coastal erosion risk management functions that may be exercised by those
authorities in relation to the area,
(c) the objectives for managing local flood risk (including any objectives included in the authority’s
flood risk management plan prepared in accordance with the Flood Risk Regulations 2009),
(d) the measures proposed to achieve those objectives,
(e) how and when the measures are expected to be implemented,
(f) the costs and benefits of those measures, and how they are to be paid for,
(g) the assessment of local flood risk for the purpose of the strategy,
(h) how and when the strategy is to be reviewed, and
(i) how the strategy contributes to the achievement of wider environmental objectives.
(5) The strategy must be consistent with the national flood and coastal erosion risk management strategy
for England under section 7.
(6) A lead local flood authority must consult the following about its local flood risk management strategy—
(a) risk management authorities that may be affected by the strategy (including risk management
authorities in Wales), and
(b) the public.
(7) A lead local flood authority must publish a summary of its local flood risk management strategy
(including guidance about the availability of relevant information).
(8) A lead local flood authority may issue guidance about the application of the local flood risk management
strategy in its area.
3.0 Flood Risk Assessment
Information on how Tower Hamlets Council has been addressing flood risk can be viewed through a series
of documents published on its website:
www.towerhamlets.gov.uk/lgnl/environment_and_planning/flood_risk_management.aspx. The documents
are the Preliminary Flood Risk Assessment, the Strategic Flood Risk Assessment and also the Surface
Water Management Plan.
The Preliminary Flood Risk Assessment (PFRA) was published in 2011 and provides a high level
overview of the flood risk in Tower Hamlets from all sources of flooding. This document was part of the
requirements for the Flood Risk Regulations (2009) and the Flood Directive and was initially commissioned
by the Greater London Authority (GLA).
The outcomes from the PFRA were extremely important in understanding what the main sources of
flooding are in the borough, and where Tower Hamlets should focus its resources efficiently, to mitigate
flood risk. The Flood Risk Zone map in the PFRA relating to fluvial flooding (Figure 3.1) describes flooding
that could occur if there were no flood defences along the River Thames and River Lee. The map is used
in planning policy to ensure any development that takes place in a flood risk zones 2 and 3 is resilient to
flooding and does not adversely contribute to the flood risk.
The high level of flood protection provided by the Thames Barrier and associated tidal defence walls,
embankments and gates on the River Thames and River Lee provide Tower Hamlets (and the rest of
London) with a world class standard of tidal flood protection of 1 in 1000 (0.1% chance in any year). There
is a residual risk of flooding from breaches of the tidal defences caused by human interference or through
defence failure. The Environment Agency has undertaken Breach Modelling (2012) which maps the
residual risk of a breach or overtopping of the flood defences at certain locations along the river. The
TE2100 Plan for managing tidal flood risk in the Thames Estuary for the next 100 years is available at:
https://www.gov.uk/government/publications/thames-estuary-2100-te2100. There remains some risk of
fluvial flooding from the River Lee in the Hackney Wick area of Tower Hamlets around White Post Lane and
Dace Road.
From Limehouse Cut to the border with Hackney there are localised areas in Tower Hamlets that were
noted as having more permeable substrate/ground, and as such a higher potential for groundwater
flooding. However this would only occur if numerous factors such as ceasing of ground water abstraction,
back to back seasons of prolonged rainfall or barriers to groundwater flow occurring. There have been no
reports of groundwater flooding, therefore the risk from groundwater flooding in Tower Hamlets is low.
Surface water flooding was thought to pose the most significant risk of flooding within the borough.
Through urbanisation, most of the surfaces in the borough are paved and surface water runoff from rainfall
is drained away via piped systems and into the combined sewer system. The sewer system was built in the
Victorian period and even though surface water helps keep the sewer clear, its capacity for rainwater is
limited. Furthermore topographical low points and underground infrastructure, such as tunnels pose a
further risk to surface water flooding.
Figure 3.1, Flood Risk Zones 2 and 3 in Tower Hamlets
Part of the PFRA highlighted areas of future development within the borough that would benefit from a
more detailed assessment of the flood risk. From this the Level 2 Strategic Flood Risk Assessment
(SFRA) was produced. The SFRA focused on development sites such as the Millennium Quarter,
Crossharbour Bishops Gate Good Yard, The Oval, Fish Island, Wapping, Leven Road Gas works,
Leamouth, Blackwall and Wood Wharf. The purpose of the SFRA was to support the Tower Hamlets Local
Development Framework, and also the National Planning Policy Framework and Planning Policy Guidance.
The SFRA provides guidance, so that a risk based, sequential approach is used in developing development
plans and that the Sequential and Exception Tests are facilitated to minimise flood risk in the future.
4.0 Investigation of Local Flood Risk in LB Tower Hamlets
4.1 Surface Water Management Plan
As part of the Drain London Project a Surface Water Management Plan (SWMP) was produced in 2011
for Tower Hamlets. It was completed in conjunction with SWMPs for neighbouring boroughs. The SWMP
describes the predicted surface water flooding for a series of rainfall events (for instance a 1 in 100 year
event, which means the event has a 1% chance of occurring in a year). The results of this computer
modelling identified Critical Drainage Areas (CDAs) within Tower Hamlets, where there was thought to be a
risk of flooding to residential properties, businesses and infrastructure. Within CDAs there are areas that
are thought to have a more significant flood risk, these are classed as Local Flood Risk Zones (LFRZs). It
is expected that during a heavy rainfall event such as a 1 in 100 year rainfall event, there would be property
flooding and potentially sewer flooding in a LFRZs. The SWMP identified 14 CDAs in Tower Hamlets.
Figure 3.2 Critical Drainage Areas within Tower Hamlets, from the SWMP (2011)
4.2 Initial CDAs
The main mechanisms of flooding were identified as topographical low lying areas and points, railway
cuttings and embankments, underpasses and finally areas where sewer surcharging was identified. Of the
CDAs identified, 9 were related to Transport for London’s (TfL) road network, London Overground and
Docklands Light Railway network, with the remaining 5 CDAs related to the public highway and the
responsibility of Tower Hamlets Council. These 5 CDAs are noted as being:
-
Group 4_013.
Group 4_021.
Group 4_074.
Group 4_025.
Group 4_011.
White’s Row
Beaumont Square
Tredegar Road
Upper North Street to Grundy Street
Plevna Street and Launch Street
To address the flood risk in these 5 CDAs, further hydrological modelling of the CDAs was completed. The
CDA in Spitalfields, Group 4_013, White’s Row, was modelled by the City Of London, as part of its
Strategic Flood Risk Assessment and the advanced modelling showed that even in an intense rainfall event
there was no significant risk posed by surface water flooding in this area. The results for this can be seen
on the City of London website (https://www.cityoflondon.gov.uk/services/environment-andplanning/planning/design/Pages/flood-risk.aspx).
The final four CDAs were remodelled by Tower Hamlets Council along with the GLA as part of the Drain
London Tier 3 programme. In the next stage, the objective was to define the current flood risk and
investigate possible mitigation options and to this end the whole of Tower Hamlets was remodelled. To
improve the precision of the computer modelling, a smaller grid size was employed (2m by 2m) and the
Thames Water sewer system was added in order to account for sewer capacity. Additional model
enhancements included the addition of land use, kerb heights and the highway drainage system (highway
gullies).
4.3 Revised CDAs
This work is currently being undertaken and not yet complete however the preliminary outcomes from this
work are highly significant. From the four CDAs identified, only one of the CDAs, Group 4_011, Plevna
Street and Launch Street remained classified as a CDA after the initial re-modelling. The flooding in the
other three CDAs had reduced significantly or completely disappeared with the addition of more realistic
information about Tower Hamlets. However, through the remodelling work, surface water flooding was
noted in the Isle of Dogs. The Isle of Dogs is a low lying area and the lowest part of the catchment.
Flooding in this area is believed to be predominantly caused by flood volumes from the wider region which
would include parts of North London exceeding the capacity of the drainage network, overwhelming the
sewers and surcharging onto the streets above.
Once complete the results from the updated surface water modelling will be incorporated into the LFRMS
and published on the Tower Hamlets website.
5.0 Mitigation of flood risk
5.1 Gullies: Our first line of defence
The removal of surface water via highway gullies is seen as the first line of defence in dealing with surface
water run-off. The highway drainage network has some 11,000 gullies and they are mapped on the LB
Tower Hamlets GIS (Geographical Information System). Gully maintenance is led in-house and is revenue
funded.
Cleansing is conducted in line with LBTH Gully Cleansing Procedure. It documents service standards,
frequency of cleansing and the procedure for dealing with broken and blocked gullies. As a rule, all
highway gullies are cleaned annually, with gullies in Town Centres or sensitive areas, such as market
places, cleaned on a quarterly basis. Records of cleansing and repairs are kept for each gully and all
emergency call outs and complaints are also recorded in order to identify areas which have recurring
problems.
Blocked gullies are identified through the cyclical cleansing programme and from enquiries by the general
public. Where possible the blockage is removed by jetting, but every year over 100 gullies must be
physically repaired or replaced.
Ponding surface water on the carriageway can be due to localised carriageway subsidence. In these
situations the surface of the carriageway is re-profiled or else new gullies are installed.
Over the past three years Tower Hamlets Council has focused resources on repairing the highway
drainage systems. Table 5.1 details the amount of gullies that have been repaired over the past 3 years.
Table 5.1 Amount of gully repairs and Emergency Call Outs (ECOs)in LBTH
2012
2013
2014
Gully repairs
83
81
112
ECOs
15
24
19
5.2 Critical Drainage Areas
Section 4.3 explained that the revised modelling identified four CDAs in which flooding is predicted to be
caused by the drainage system of sewers being overwhelmed. The four CDAs are drained by the same
pipe network, which flows north through Abbey Mills pumping station and onto Beckton. The mean high
water spring tide level for the Isle of Dogs is 4.1m AOD and the River Thames is 1-3m AOD, thus water is
unable to discharge freely to the River Thames. At present it can discharge into the River Thames via the
pumped Combined Sewer Overflow (CSO), however foul water is discharged into the River Thames, which
is detrimental to the River Thames and an unsustainable way of dealing with surface water. Removal of
water in the sewers is thus wholly reliant on the pumped drainage network through Abbey Mills and this
hasn’t sufficient capacity during more extreme rainfall events such as a 1 in 100 year event.
As the flood water is from surcharging combined sewers it would be contaminated (foul waste) and cannot
be stored in any form of SuDS. The flooding cannot be solved by larger pipes or other storage capacity as
this would merely serve to attract more dirty water to the area. It would be like trying to dig a bigger hole in
the sand in the hope that water would drain away. Through the updated surface water modelling the
impacts of the increasing the capacity of a smaller local pump within the Isle of Dogs will be investigated,
as will increasing the pump rates at Abbey Mills by 50%. Further to this, modelling the surface water runoff
solely on the Isle of Dogs, and not incorporating the surface and foul water from the rest of the catchment
will also be investigated. As initial results have shown flooding on the Isle of Dogs, it is important to
understand whether this is a local problem with surface water drainage on the Isle of Dogs or whether it’s
actually caused by wider surface water and sewer system from north London.
Another, more radical option is the possibility of diverting the water via a pipe from the Isle of Dogs into the
Thames Tideway Tunnel (TTT), which follows the path of the Limehouse Cut through the borough to Abbey
Mills. It might seem that there may be an opportunity of joint working with Thames Water and developers.
However, whilst Thames Water Utilities agrees that it is an attractive solution from a technical perspective
they perceive difficulties in obtaining permission from the future lessors of TTT. It would be for Thames
Water to take this option further and it is clear that this is not a solution that can be depended upon.
The long term plan for mitigating flood risk in CDAs are to seek funding from the Flood Defence Grant in
Aid (FDGiA). As the integrated surface water modelling of Tower Hamlets is still ongoing, preliminary
FDGiA proposals include:
i.
ii.
iii.
iv.
v.
Carry out a level survey and identify which kerbs and properties will be flooded.
Identify where we can store dirty water in the highway through raising kerb heights
Identify which manhole covers should be bolted down
Identify suitable means of property level protection
Estimate costs of the above
Looking to the future Tower Hamlets would seek further funding not only from FDGiA but also Community
Infrastructure Levy, developers, Thames Water Utilities and any other relevant funding sources together
with contributions from affected property owners to implement measures and thus effectively mitigate the
risk of flooding. Furthermore the Thames Region Flood & Costal Committee (RFCC) allocates funding to
flood mitigation projects with local importance. The money is gained through a levy on Council Tax payers,
and then administered by the RFCC, each year £10.5m is administered across the River Thames
catchment. More information on this can be found at https://www.gov.uk/government/groups/thamesregional-flood-and-coastal-committee.
5.3 Sustainable Drainage Systems (SuDS)
SuDS are a modern way of dealing with surface water run-off, with the aim of mimicking natural drainage,
thus relieving the pressure on the sewer system and consequently mitigating flood risk.
Individual SuDS cannot be expected to provide significant relief to major flooding. However, they provide a
means to capture surface water where it falls and prevent it from contributing to an overwhelming of the
sewerage system or to flooding in low-lying basins downstream. It has to be the case that if there were
sufficient SuDS installed nationally, then any flooding problems would be dramatically reduced. Tower
Hamlets is playing its part in building a stock of SuDS in the borough focussing on where they can be most
effective and/or where they can be delivered most efficiently
Tower Hamlets has a policy of installing SuDS in the Public Realm and along the Public Highway to absorb
surface water and has been a lead borough in their installation on roads that could not be described as
quiet. To date there have been multiple SuDS schemes in Tower Hamlets led by the Council on the Public
Highway including, rain gardens and tree pits on Bethnal Green Road, Grundy Street and Bygrove Street
together with an innovative SUDS scheme on Derbyshire Street which encompasses six SuDS, rain
gardens tree pits, small scale green roofs, attenuation rain water planters, permeable paving and a swale.
Tower Hamlets will focus on installing SuDS in highways in relatively low-lying basins where surface water
tends to pool and will also take the opportunity to install them where other work on the highways is already
taking place and where SuDS can thus be installed relatively cheaply. This work will continue in the
coming years, with the aim of making SuDS in highways schemes normal, not novel, practice. These
works will be funded through Section 278 and 106 agreements and (when implemented) the Community
Infrastructure Levy (CIL). Where general highway maintenance, major planned highways works and
greening of streets is taking place, such as tree planting, the use of SuDS will be considered.
There are multiple additional benefits of using SuDS rather than conventional drainage systems, such as
the creation of green space and green corridors, improved biodiversity, improvements in water quality and
air quality, to name but a few. The use of SuDS is not only linked to flood risk but also other Tower
Hamlets strategies and London wide documents, such as:
-
The Tower Hamlets Green Grid Strategy:
http://www.towerhamlets.gov.uk/lgnl/environment_and_planning/conservation.aspx
The Tower Hamlets Local Biodiversity Action Plan: http://www.towerhamlets.gov.uk/lgsl/551600/596_biodiversity.aspx
Tower Hamlets Local Plan: http://www.towerhamlets.gov.uk/lgsl/451500/494_planning_guidance/local_plan.aspx
The Mayors for London’s Air Quality Strategy:
https://www.london.gov.uk/priorities/environment/clearing-londons-air
The London Plan: https://www.london.gov.uk/priorities/planning/london-plan
5.4 LBTH SuDS Guidance
In response to Schedule 3 of the FWMA and the increasing use of SuDS by Tower Hamlets Council and
developers, the Tower Hamlets SuDS Guidance has been produced
http://www.towerhamlets.gov.uk/lgnl/environment_and_planning/flood_risk_management.aspx
The document was created in house with technical expertise sought from Sustainability Centre at The
University of East London. The guidance not only provides the legislative background on Flood
management but also outlines six key SuDS features that are highly applicable for use within the borough;
these are green roofs and small scale green roofs, engineered tree pits, rain gardens, swales, attenuating
planters and permeable/porous paving. In addition the guidance also has information on calculating the
water storage capacity of SuDS.
5.5 Changes to Surface Water Planning Advice
The Department for Communities and Local Government (DCLG) provided a ministerial statement
proposing to make LLFAs the statutory consultees on surface water management for all major planning
applications and removing the Environment Agency’s statutory consultee role for development sites greater
than 1 hectare in Flood Zone 1
The Authority has built a competence in this area and is confident that it will be able to meet its
responsibilities.
6.0 Partners in flood risk mitigation
6.1 Tower Hamlets Council
There are regular meetings of the Flood Group comprising of Tower Hamlets officers who work on planning
policy and on development control, environmental health, emergency planning, and highways
implementation together with an officer from Environment Agency. We discuss and monitor progress on
the implementation of the Surface Water Management Plan, the SuDS guidance and a sub-group has
become the SAB (SuDS Approval Body) working party to implement a SAB.
6.2 Neighbouring Boroughs
Tower Hamlets officers meet with officers from the London Boroughs of Newham, Hackney, Waltham
Forest, Haringey and Enfield, along with representatives of Thames Water and the Environment Agency in
Drain London Group 4 meetings. These are used to share joint responsibility for issues within the Lea
Valley catchment but also to provide a forum for peer support to tackle more effectively duties and problem
that are common to all boroughs. On a London-wide level, we attend Drain London meetings and LoDEG
(London Drainage Engineers Group) to share knowledge, solutions and work.
6.3 Transport for London (TfL)
Within the borough, we work with partners who also have clear responsibility for mitigating flooding and its
impact. Transport for London has responsibility for dealing with the flooding that is predicted to occur on
their property, for example, in subways, along the Red Route Network and railway cuttings. We have made
them aware of the CDAs in which this is an issue and we await their advice to us of their proposed action.
6.4 Statutory Undertakers
Statutory undertakers have been asked of the impact of flood water on their equipment and service
delivery. They have been requested to advise LBTH of the measures they have to protect their services
and/or what they will do if it’s damaged by flooding.
6.5 The Environment Agency
The Environment Agency has a strategic overview of all sources of flooding and coastal erosion (as defined
in the F&WMA 2010). This includes setting the direction for managing the risks through strategic plans;
providing evidence and advice to inform Government policy and support others; working collaboratively to
support the development of risk management skills and capacity and providing a framework to support local
delivery.
Working in partnership with the Met Office, the Environment Agency aids in providing flood forecasts and
warnings. It must also look for opportunities to maintain and improve the environment for people and
wildlife while carrying out all of its duties. It has powers to undertake maintenance, carry out improvement
works and to issue consents for 3rd party works. However, it only has a duty to carry out maintenance on
its own structures. Responsibility for watercourse and defence maintenance generally rests with the
riparian owner.
In Tower Hamlets the Environment Agency is responsible for managing and maintaining the Rivers Thames
and River Lee.
6.6 Canals and Rivers Trust
The Canals and Rivers Trust (C&RT) for the Limehouse Cut, Lee Navigation, Hertford Union Canal and
Regents Canal. The Limehouse Cut and Lee Navigation are classified as main rivers, however owned and
maintained by the C&RT.
6.7 Thames Water
Thames Water has a major role in flood mitigation as the organisation is responsible for the operation and
maintenance of the sewerage system that transports away waste water and surface water.
6.8 Private Sector and Housing Associations
We have yet to identify any private sector partners who have a role in flood mitigation but expect that this
will happen when we identify specific properties that need protection and thereby have specific landowners
and property occupiers with whom to work. Tower Hamlets officers meet with Housing Associations
annually to share new information on flood risk and the implementation of SuDS throughout the borough.
7.0 Registers & Records
7.1 Flood incident Register
Since 2010 the London Borough of Tower Hamlets has maintained a detailed flood incident register. The
register is designed to record all flooding incidents in the borough, and is available to view on the Tower
Hamlets web page in a GIS form and excel sheet.
Through the detailed investigation and recording of flooding incidents, areas which are susceptible to
flooding can be identified and any alleviation measures taken.
7.2 Asset Register
As part of the Flood and Water Management Act (2010), section 21, all Local Authorities have a duty to
maintain an Asset Register. The register lists all structures in critical drainage areas which may affect the
flood risk. Through identifying these structures the London Borough of Tower Hamlets is able to highlight
these structures as key infrastructure relating to flood risk and increase the inspection rate of these
structures.
LBTH Asset register is kept in GIS form, it is currently being populated on Floodstation.
8.0
References
[1] Flood and Water Management Act (2010)
[2] Highways Act (1980)
[3] Chatterton, J., Viavattene, C., Morris, J., Penning-Rowsell, E., and Tapsell, S., 2010. The Cost of the
summer 2007 floods in England, Environment Agency.
9.0 Review
The LFRMS will be reviewed at least annually. It is an electronic document with live links to documents
which would also be reviewed and updated annually.
Date to be reviewed
Reviewed by
June 2015
December 2015
December 2016
December 2017
10.0 Revisions
Revisions to this document are recorded below in the Revision Table
Section
Revision
Consultation Draft
Date