Agenda item
SECTION 19 INVESTIGATION REPORT ON THE FEBRUARY 2020 FLOODS IN DENBIGHSHIRE
To consider the Section 19 Flood Investigation Report (copy attached) from the Head of Highways & Environmental Services and Flood Risk Engineer on the 2020 floods in Denbighshire.
10:15 – 11:00
Minutes:
In his introduction the Lead Member for Waste,
Transportation and Environment in his introduction, Councillor Brian Jones,
highlighted that the flooding experienced across Denbighshire in February 2020
had been a significant event. The Head
of Highways and Environment (TW) introduced the Section 19 Flood Report
(previously circulated) relating to the floods which had occurred as a result
of Storm Ciara. Denbighshire County Council as a Lead Local Flood Authority had
a duty under Section 19 of the Flood and Water Management Act to investigate
flooding and publish the findings.
The majority of the flooding had occurred from main rivers –
Ceidiog, Clwyd, Elwy and Ystrad - which came under the remit of Natural
Resources Wales (NRW) for investigation. There was also some surface water
flooding which was the responsibility of Denbighshire County Council to
investigate.
The report sought to answer 3 questions in relation to each
area that was flooded:
1.
Why did the flooding happen?
2.
How likely was it for that scale of flooding to
happen again in that location?
3.
What improvement actions were needed to ensure
that flood risk in the County was appropriately managed in future?
The majority of the recommended improvement actions fell to
NRW to progress (pages 33 to 35) as they had the authority and the powers to
take action on main rivers.
Members expressed disappointment that the majority of
information contained in the report related to responsibilities that were
within the gift of NRW but there was no NRW representative at the meeting to
respond to questions arising from it.
Officers advised that the report itself contained the findings of the
Council’s investigation into the flooding and its causes, the intention was to
present the report, accompanied by the Committee’s comments to County Council
in September 2021. If members wished
representatives from NRW could be invited to attend that meeting. It was agreed to request an update from NRW
on intentions relating to their recommended actions and timescales to be
included in the report that was to go to full Council and that NRW
representatives be invited to attend.
Members also requested that a historical report or
presentation be provided by NRW on rainfall measurements over the previous 10
to 15 years (within Denbighshire), along with an analysis on the quality and
reliability of data from rain gauges.
This could assist the Authority to gauge the potential impact of climate
change on flooding locally. This
information could possibly form part of the business item at the County Council
meeting in September, or presented to the Flood Risk Management and Riparian
Land Ownership Task and Finish Group.
It was confirmed that NRW had already been invited to
present the findings of their modelling work in relation to Rhyl Cut and
Prestatyn Gutter, at Communities Scrutiny Committee on 9th September 2021.
Responding to members’
questions officers’ advised:
·
Rain gauges and river level stations were the
property of NRW. Clarification would be sought as to their degree of accuracy.
·
With regards to data gathering DCC had some
telemetry at key locations, their purpose was to notify the Authority of high
river levels in order to respond to potential blockages. DCC were looking to
add telemetry to smaller water courses in future.
·
The Authority’s remit was to understand the
pattern of risk of flooding within the County.
·
The assessment of risk terminology adopted by
NRW e.g. 1 in 100, could be confusing and potentially led to the belief that it
was a low risk of flooding.
·
New housing developments were covered by TAN15
planning guidance which sought to achieve a protection of 1 in 1000 annual
exceedance probability. There were no national standards for existing
developments.
·
There was no clear indication that climate
change was having a significant effect on flooding as weather behaviour tended
to be cyclical.
·
Where possible the technical mitigation should
be identified to alleviate the risk of flooding existing developments. However,
sometimes there was no possible technical mitigation or the cost of
implementing it was prohibitive.
·
Priorities needed to be established around
places where there could be a defence through mitigation – noting that the risk
would only be impacted, not removed.
·
That every effort had been made by Council
officers to assist individual residents and communities affected by main river
flooding to enter into dialogue with NRW about reducing the risk of flooding in
future.
At the conclusion of an in-depth discussion the Committee:
Resolved: subject to the above
observations and the provision of the additional information requested when the
report is presented to County Council in September 2021, to recommend that the
Council -
I.
seeks assurances from Natural Resources
Wales at its September 2021 County Council meeting that the recommendations
identified in the Natural Resources Wales’ flood investigation reports will be
carried out, and that the anticipated timescales for their implementation and
completion be confirmed; and
II.
through the Flood Risk Management and
Riparian Land Ownership Task and Finish Group, seeks assurances from Natural
Resources Wales that flood risk from main rivers in Denbighshire is being appropriately
managed.
Supporting documents:
- Feb 2020 Flood Investigation Report 010721, item 6. PDF 311 KB
- Feb 2020 Flood Investigation Report 010721 - App 1, item 6. PDF 312 KB
- Feb 2020 Flood Investigation Report 010721 Appendix A, item 6. PDF 990 KB
- Feb 2020 Flood Investigation Report 010721 Appendix B, item 6. PDF 23 MB
- Feb 2020 Flood Investigation Report 010721 Appendix C, item 6. PDF 2 MB
- Feb 2020 Flood Investigation Report 010721 Appendix D, item 6. PDF 2 MB