Members Seminar 15 September 2014
Flood Risk
• Christina Harrhy – Chief Officer, Neighbourhood
Services
• Stephen Jarrett, Andrew Villars, Mark Strickland
– Highways and Transportation
• Rob Murray – Forward Planning, Local Planning
Authority
Flood Risk
An opportunity to present on:
• Flood Risk Management
• Operational activities
• The flooding event of 22 May 2014
Flood Risk Management
• Main Legislation – Flood and Water Management
Act 2010
• TCBC was identified as one of 8 areas in Wales as
including a significant flood risk area by the
Environment Agency in 2011
• The flood risk area covers an area from
Abersychan in the north, to Cwmbran in the south.
Flood Risk Management
• What do we need to do?
• Preliminary Flood Risk Assessment Report – Completed in
accordance with required timescales
• Flood Risk Management Strategy – Completed in
accordance with timescales, and is now Council Policy
• Flood Risk Management Plans – Ongoing, to be completed
by June 2015
• This completes a five year cycle and will recommence in
2016/17
Flood Risk Management
• The FWMA requires us to:
• Develop, agree, maintain apply and monitor a Flood Risk
Management Strategy to satisfy the requirements of the
Act, which is to identify and where possible and
practicable, reduce the risk of flooding
• The FWMA does not require us to:
• Prevent flooding
• Act on behalf of another Risk Management Authority e.g.
Welsh Water
Flood Risk Management
• The three main themes of the Strategy are:
• To reduce the risk of flooding
• To increase the preparedness for flooding
• To increase the protection against flooding
Operational Activities - Culverts
• We have long been carrying out maintenance of
culvert entrances to reduce the risk of flooding
• An agreed system has been devised whereby
operatives inspect, report and where necessary
cleanse debris from culvert entrances. This
extends to 229 culvert entrances across the County
Borough.
• We have dedicated resource of two operatives, and
a vehicle
Culvert Landrover
Operational Activities - Culverts
• Routine culvert inspections
• This regime attaches a risk priority number to each culvert
based on factors such as catchment size, culvert capacity
and flooding consequences. The areas around the culvert
entrance are routinely cleansed, not extended lengths of
watercourse.
Priority
Winter
Summer
1
2
3
Weekly
Fortnightly
Monthly
Fortnightly
Monthly
Bi-monthly
Operational Activities - Culverts
• Adverse weather conditions
• Where information from the Met Office indicates, or
officers consider necessary, additional ad hoc inspections
may be undertaken
• This can necessitate the redeployment of resources to assist
the dedicated crew
• It can also necessitate redeployment of staff to
continuously monitor culvert entrances
Operational Activities - Culverts
• Capital investment
• Major schemes were been carried out to reduce risk in
areas across the County Borough, mainly pre 96.
• Minor schemes primarily to improve security/trash screens
have been undertaken since 96, to improve to the then
current standards.
Operational Activities – Gully Cleansing
• We have an agreed process for gully
cleansing for those gullies on the adopted
highway network, this extends to some
17 500 gullies.
• There are gullies in the control of others
• We have a dedicated resource of two
operatives and one gully sucker
Gully Sucker
Operational Activities – Gully Cleansing
• Routine Inspections
• With the available resources, the schedule is pressurised.
• We operate an inspect and cleanse regime aiming to
cleanse as necessary once per annum
• We are aware of areas where highway drainage is not
functioning, but these can include areas where more major
maintenance is necessary to repair connections. These area
are assessed and where necessary works have to be
considered against competing pressures within the overall
programme
• We are fulfilling our statutory duties
Operational Activities – Gully Cleansing
• Adverse weather conditions
• Similar to our response to culverts, if necessary, we would
seek to ensure we have the best response available in
adverse weather conditions that could include ensuring the
availability of the gully sucker out of hours as a responsive
asset.
Operational Activities – Gully Cleansing
• Capital investment
• Via the Welsh Government Local Government Borrowing
Initiative and previous Authority prudential borrowing we
have invested approximately £300K over the last four
years in repairing long standing defective parts of the
system. There is no formal indication at present that the
LGBI funding will be continued beyond this financial year
• Others Factors
• It is not unheard of for others to damage our drainage
systems that may not be known for many years
Statutory Undertaker Damage
Flooding Event 22 May - Cwmbran
• As Lead Local Flood Authority, we have produced
a Section 19 Report in accordance with the Flood
and Water Management Act 2010
• The report details the event, the reasons for the
flooding, and makes a series of recommendations
that will be explored in detail in the coming
months in accordance with our duty
Flooding Event 22 May - Cwmbran
• The event
• The event was an extreme localised event that has been
assessed as a greater than 1 in 100 year event, with Met
Office data advising an intensity of 78mm/hr, although this
is thought to have been exceeded in some areas
• The impact of the event caused internal flooding to 198
properties
• The culvert inspection and cleaning and gully cleansing
schedule were in accordance with our schedules prior to
the event
• Two supermarkets were structurally damaged
Oldbury Road
Fairhill
Penmaes Road
Gifford Close
Cwmbran area
Flooding Event 22 May - Cwmbran
• Reasons for flooding
• 198 properties were internally flooded and these have been
categorised into the following:
• 108 properties from culvert overloads
• 26 properties affected by the public sewerage system,
although Welsh Water have only received 20 contacts from
residents
• 64 properties from overland flows such as garden run off,
run off from highways
Flooding Event 22 May Cwmbran
• Recommendations
• The use of community engagement and awareness
programmes as set out in the Strategy will develop the
resilience of communities
• Where deemed appropriate and in line with the Strategy,
there may be works carried out by the Authority consisting
of small scale works to redirect surface flows and to create
flood paths. There needs to be a clear return on
investement
• The consideration of our maintenance regimes
Flood Risk – The Future
• Climate change
• The systems and regimes for reducing flood risk
are evolving
• There may be a need for capital investment that
the Council will need to consider
• Public engagement and engagement with our
partners is necessary, and the responsibilities of
the RMA’s, and residents and property owners,
needs to be understood
Flood Risk - Summary
• We have a responsibility to reduce the risk of, not prevent,
flooding
• We have a proactive and reactive approach to fulfilling our
duties
• The event of the 22 May was extreme and if it happened
again in the County Bourogh would likely have similar
consequences
• We are happy to engage with the community as per our
Strategy