Homes and Environment Scrutiny Committee. (Environment & Transport)

Transcription

1 REPORT TO: REPORT NO: Homes and Environment Scrutiny Committee HHPPE/89/15S DATE: 9 September 2015 LEAD MEMBER: Councillor David A Bithell (Environment & Transport) CONTACT OFFICER: Neil Taunt (Tel: ) SUBJECT: WARD: Surface Water Flooding All 1. PURPOSE OF THE REPORT To increase awareness of the differing roles and responsibilities of Wrexham CBC as Lead Local Flood Authority, Natural Resources Wales and Welsh Water with regards to flood risk management, and to promote the Authorities strategic approach to the management of surface water flooding and continuing development of a register of significant assets as required under the Flood and Water Management Act (2010). 2. EXECUTIVE SUMMARY 2.1 Wrexham County Borough Council as Lead Local Flood Authority (LLFA) is responsible for local flooding issues associated with surface water within the Authority area. 2.2 As LLFA, the Authority has a statutory duty under the Flood and Water Management Act (2010) to produce and maintain a register of significant flood risk assets, including those associated with surface water flood risk. 2.3 This asset register work is ranked as a medium to long term priority for the Local Authority within the Local Flood Risk Management Strategy (LFRMS). The scope of the asset register is based on significant flood risk assets and does not include all types of drainage infrastructure. 1

2 2.4 The Flood and Water Management team are currently developing the asset register for the Local Authority in line with Welsh Government s best practice of a nationally consistent template and will support a long term, risk-based approach to local flood risk management. This includes asset data from a number of partner organisations (including Natural Resources Wales, Welsh Water and Canal & Rivers Trust). 2.5 Prioritising significant assets combined with awareness raising within at risk communities of the responsibilities associated with riparian ownership will assist in building resilience to future flood risk. This will also assist in delivering partnership approaches for proposed flood alleviation projects and acceptance of the future local flood risk management plan. 3 RECOMMENDATIONS 3.1 Members note the current arrangements for managing surface water flooding and support the continued development of the asset register and its contribution to the strategic management of surface water flooding and flood risk. 3.2 A further report on work plan and asset register progress be made in summer REASONS FOR RECOMMENDATIONS (i) (ii) Wrexham County Borough Council as a Lead Local Flood Authority has a statutory duty under the Flood and Water Management Act 2010 to manage local flood risk; this explicitly includes surface water flood risk. The continued development of an asset register database systems within the LFRMS framework will enable the Council to take a strategic approach to flood risk management, ensuring limited resources are prioritised to the areas of most significant risk, and enable a faster and proactive approach to the resolution of surface water flooding issues before they occur. 4. BACKGROUND INFORMATION 4.1 Surface water flooding and flood risk management work associated with the LLFA covers work undertaken by departments across the Council. In Wrexham this is, since June 2015, led by the Flood and Water Management team within the Housing, Public Protection and Environment Department, with a local officer lead and collaboration with local partners and organisations. 4.2 The background of this report dates back to The most recent and relevant reports include; CPLO/47/10 and CLDSO/10/10 on flood management work and the surface water flooding scoping report. The minutes (24) of the Audit Committee and drainage/sewerage infrastructure residual risk (Housing and Public Protection HP041) dated 20th December 2012; and 2

3 The local flood risk management strategy report approved by Executive Board on 8th January 2013 (HWCD/70/12) and approved by Welsh Government in April Roles & Responsibilities 4.3 The roles and responsibilities of the various Authorities and Organisations involved with flood risk management are clearly defined within the Flood and Water Management Act 2010: The LLFA is responsible for local flood issues associated with surface water, groundwater and flooding from ordinary watercourses. Natural Resources Wales (NRW) is responsible for river flooding issues associated with the designated main river network. Welsh Water (WW/DC), as local sewage undertaker, is responsible for flooding issues associated with the public sewer network As LLFA, Wrexham CBC is required to carry out a number of statutory duties, including: Preparation of a Local Flood Risk Management Strategy (LFRMS) Compliance with National Strategy Co-operate with other authorities, including data sharing Appropriate investigations of all flooding incidents within its area Maintain a register of structures and features likely to affect flood risk Contribute to sustainable development Ordinary watercourse consenting. 4.5 The LLFA are also granted a number of permissive powers, including: Powers to request information Powers to designate certain structures or features that affect flood risk Powers to undertake works Ability to cause flooding under certain conditions. 4.6 Appendix 1 contains an Action Plan describing the Flood & Water Management Teams current strategic and operational work areas, role and responsibilities. 4.7 Representatives from the various risk management authorities have been consulted on the content of this report and are able to attend future meetings to provide additional information on specific topics or responsibilities as required. Surface Water Flooding 4.8 Wrexham County Borough Council as a LLFA has the lead role in relation to management of surface water flooding, and has a statutory duty to maintain a register of significant flood risk assets such as bridges, culverts, flood defence walls, bunds etc. 4.9 These assets are often associated with highways, forming a group of assets relating to the Highway Asset Management Plan. These assets do not include the 3

4 infrastructure associated with water provision (owned by Dee Valley Water), adopted public sewers (responsibility of Welsh Water), or drainage systems within the ownership of private individuals or landowners The requirement for the asset register is set in LFRMS measure L3 and forms a medium risk and long term priority. It forms one of eleven measures set out in the framework of the LFRMS adopted by the Local Authority in April This approach is also supported by LRFMS measure L8 promoting a greater level of community resilience, awareness and preparedness which encourages proactive and responsible maintenance of privately owned assets and flood defences. Updated Flood Map for Surface Water Flooding 4.11 The updated flood map for surface water flooding (published Feb 2014) and flood risk maps for rivers, sea and reservoirs all form the output of an Environment Agency project and were published across United Kingdom in December 2013.These maps are available to the public from the NRW website ( Surface water flooding forms one of the three main forms of flood risk which needs to be appropriately managed by Wrexham County Borough Council in partnership with key flood risk partners of Welsh Water and Natural Resources Wales These flood risk maps, along with watercourse designations and areas susceptible to groundwater flooding, all form layers on the corporate mapping system, and form a trigger for internal consultations between Planning Policy, Development Control and the Flood and Water Management team. This allows local data on flooding to be taken into account within the planning system, and also enables the LLFA to take the lead role in ensuring surface water runoff from all new developments is managed appropriately, contributing to statutory sustainable development goals The corporate use of the available flood risk mapping, in conjunction with historic flooding incidents, helps to identify, assess, plan and review approaches to flood risk management work across council departments. Surface Water Flood Risk 4.15 Surface water flooding occurs following locally intense rainfall which, due to the large volume of water, exceeds the ability of either the ground to infiltrate water, or for the ability of the local drainage system to cope. Due to its localised nature, it is very difficult to forecast surface water flooding accurately, with very little lead time available for warning. Despite the generally localised nature, surface water flooding can result in locally deep, fast flowing water that will cause disruption to travel networks, flooding of land and properties, and a risk to life of the people affected Surface water flooding was highlighted in the LFRMS as being the most prominent source of flooding to affect Wrexham CBC, associated with increased runoff from paved surfaces impacting low lying properties, especially in areas of insufficient drainage or areas prone to blockages. Indicative communities highlighted as being at an increased risk of surface water flooding include Wrexham town centre, Llay, Rhos, Cefn Mawr, Rhosnesni, Gwesyllt, Coedpoeth, Bradley, Llan y Pwll and Chirk. 4

5 4.17 The updated maps for surface water flooding highlight that across the County Borough there are in the order of 1000 properties at risk during a 1 in 30 year (33.3% Annual Exceedance probability (AEP) event), 4500 during a 1 in 100 year (1% AEP) event and during a 1 in 1000 year (0.1% AEP) event. The communities identified above (4.16) contribute significantly to this total In the last three years (2012 to 2015) the County Borough has recorded approximately 2500 flooding incidents to 2014 included some of the wettest years on record; correspondingly there were approximately 1000 incidents per year, a much reduced number recorded from 2014 to 2015, corresponding with a much dryer period. The majority of incidents recorded appear to represent repeat events in urban areas and villages which are more susceptible to heavy and persistent rainfall. Flooding incidents are recorded by the Contact Centre and in % (increasing to 90% in ) of incidents or reports made to the Council were associated with Council gullies, 13% with surface water flooding and 7% with requests for sandbags Flooding incidents in largely coincided with a range of higher than average rainfall totals and responding river catchments associated with River Dee. Incidents recorded for previous year were associated with flash flooding, rising river levels, ground saturation and surface water flooding It is now accepted that more frequent and heavier rainfall periods associated with the impacts of climate change will impact on flood management work, including asset management, flood awareness, development planning, regeneration and rural economic development. Register of Significant Flood Risk Assets 4.21 In accordance with the National Flood Risk and Coastal Erosion Risk Management Strategy significant work has been done nationally and regionally on the development of an asset register. Work continues to form an important part of the regional flood risk management group in North Wales and two replica groups for South East and South West Wales The asset register database work has involved the formation of a number of generic national templates. These have been used to establish a consistent approach to the use of databases and geographical information systems across the 6 Authorities across North Wales To date Wrexham County Borough Council has made good use of existing database systems (Symology and BMX) and are working collaboratively with adjacent local authorities (Denbighshire and Flintshire) to develop a consistent system of recording, reporting and monitoring assets whilst appreciating the limited resources available Working with partners, the asset register forms four key phases of work; Phase 1: COMPLETE has identified and obtained data held internally across the Authority, complete with asset data from Network Rail, Canal and River Trust, Welsh Water and Natural Resources Wales. Phase 2: ONGOING Identify and obtain significant assets in Wrexham town centre and Wrexham Industrial Estate. 5

6 Phase 3: Builds on Phase 1 and 2 to obtain and attribute significant assets in private ownership, associated with flooding events or significant flood risk areas identified by surface water flood risk maps. Phase 4 will involve publication of a suitable version of key assets within the asset register database Raising flood awareness and attributing a relevant maintenance regime to higher risk assets forms two continuous requirements across all phases of the asset register work (significant issues on flood awareness were raised by members of our communities during the consultation on the local strategy and from data recorded during flooding incidents) A summary of WW/DC recent and planned works that aim to improve resilience to surface water flooding associated with the public sewer network can be found in Appendix Privately owned assets do offer a number of challenges. There are no specific powers awarded to the LLFA to ensure works on failing assets are carried out. The FWMA has given the LLFA the power to issue a notice to request information from the owner of a structure, with appropriate enforcement provision if the notice is not complied with The LLFA can designate features that have a significant impact of flood risk. Although this does give control over alterations or works to these designated structures, it does not give the provision to order works to be carried out. Existing enforcement provisions with the Land Drainage Act are still valid, with the ability for the LLFA to carry out works and recharge where a significant flood risk exists due to the failure of, or lack of maintenance of, an ordinary watercourse or structure. Asset Maintenance 4.29 Differing types of assets will have different inspection and maintenance requirements. These vary according to their overall condition, status, location and design, but ultimately this would be dictated by the flood risk associated with failure of the asset. Inspection surveys and flooding incidents are likely to include the review of maintenance regimes, identifying any remedial work required It is important to understand that not all significant flood risk assets are owned or maintained by the Local Authority, or partners identified above (4.23). Land owners have riparian responsibilities to maintain assets, including bridges, culverts, permeable pavements/driveways and soakaways All highway structures, including bridges and culverts with a diameter over 900mm running under public highways, are inspected in accordance with the Management of Highway Structures A Code of Practice. These must be inspected, at a minimum, every two years Highway gulley maintenance frequencies are defined within the Streetscene Service Standards (January 2009). Current standards, shortly up for review, are for routine cleaning (emptying & jetting): Gulleys in known flooding areas to be cleaned twice per year. 6

7 All other gulleys to be cleaned every two years. There are 13 maintenance schedules (with #13 covering sites that required traffic management). Streetscene will react to incidents outside of the defined schedules. Outputs and Outcomes 4.33 Significant or repeat reports of surface water flooding incidents are likely to trigger investigations into possible remedial or mitigation works to minimise the future impact. This could result in recommendations for works on third party assets, or the inclusion of mitigation to reduce the amount of surface water generated locally (this could include retrofitting Sustainable Drainage techniques into existing communities to promote infiltration and slow down the generation of surface water). These data will also provide evidence that can be used to identify opportunities for partnership projects with Dwr Cymru / Welsh Water and Woodland Trust for projects such as surface water amelioration to schools (or SWATS), which can deliver educational learning material, increase flood awareness and engagement and reduction in surface water flood risk This asset register work has already contributed to the scoping of potential flood alleviation or infrastructure improvement projects associated with the wider River Gwenfro catchment for Wrexham town centre It has also helped to identify potential opportunities to work across departments and with partners on rural development programmes associated with AONB and the climate change agenda led by Cadwyn Clwyd and a potential flood resilience project with the Housing Energy Efficiency Team (HEET) for improving flood resilience to existing or new housing The work continues to inform the wider development of Wrexham CBCs local flood risk management plan which should be the subject of further reporting during Policy Framework Ensuring the register of significant flood risk assets is fit for purpose will help the Local Authority to deliver its duties of the Flood and Water Management Act It will contribute to PL3: Place: Investing in attractive, safe and inclusive communities. To ensure that we are environmentally responsible County Borough and PE3: People: Raising Aspirations, creating confidence and promoting opportunity Budget 4.39 Legal There are no immediate budget implications arising from this report, but with time as the asset register is developed, this may impact on asset management plans and capital programme bids. As a Lead Local Flood Authority, Wrexham County Borough Council has statutory duties to manage local flood risk effectively through the implementation of a significant flood risk asset register. The Local Authority is demonstrating good practice in relation to its statutory duties and responsibilities maintain an asset register and raise 7

8 awareness of flood risk associated with maintenance of assets to mitigate risks and improve overall resilience of our communities Staffing There are no staffing issues arising out of this report Equality/Human Rights 4.42 Risks The diversity of our communities and range of engagement activities is integral to wider flood awareness and community resilience engagement programme. Failure to comply with statutory duties would have significant impact on social environmental and economic on the local authority and members of our communities and on current grant funding provided by Welsh Government. 5. CONSULTATION Not applicable 6. EVALUATION OF OPTIONS Not applicable 8

9 BACKGROUND PAPERS Background Papers Location Website Link 1. Local Flood Risk Management Strategy Wrexham January 2013 (HWCD/04/13) Executive Board Council MinutesData/ExBoard/ex Preliminary Flood Risk Assessments CPLO/47/10 November 2010 Homes and Environment Scrutiny Committee 3. Surface Water Flooding CL050/10/10 24TH June 2010 Homes and Environment Scrutiny Website Wrexham Council Website Wrexham Council Website Committee 4. Audit Committee 20/12/2012 Wrexham Council Website 12013m.htm MinutesData/EnvRegen/Rep orts/cplo4710s.doc MinutesData/EnvRegen/er m.htm MinutesData/Audit/au m.htm 9

10 Appendix 1: 10

11 Appendix 2: Details of recent and planned Welsh Water / Dwr Cymru works to minimise surface water related flood risk. The information supplied by DCWW below is based on the best available information at the time of drafting and may be subject to change. This data is to provide an outlook to the Members and Scrutiny Committee and should not be circulated to any third party without prior consent from DCWW. Water and waste water assets within WCBC. DCWW does not supply potable water to the WCBC area therefore there are no impounding reservoirs or service reservoirs that are owned or serviced by DCWW. Below ground sewers The approximate length of below ground sewer network is 854 km of which km are owned by DCWW and the remaining 51.5 km remain in private ownership. Pumping stations There are 73 of which 44 are DCWW owned with the remaining 29 in private ownership. Waste water treatment works There are 28 of which 27 are DCWW owned and 1 remains in private ownership. Recent or planned capital asset schemes (surface water flooding) Investment There have been 9 schemes delivered in the WCBC area during the past 5 years to resolve sewer flooding. They are as follows: Wrexham (Box Lane); Coedpoeth (Maes Tyddyn); Wrexham (Warrenwood Road); Llanarmon DC (Wynnstay Arms); Llanarmon DC (Minffordd); Gwersyllt (Oakland Court); Gresford; Pontfadog (Dolydd); Bangor-is-y-Coed (High Street) Investment There are currently two schemes planned for delivery, subject to programme prioritisation as new risks emerge. These are listed below: Ruabon (Shellbrook Drive) We believe that the issue has already been partly mitigated following initial investigations and we are currently scoping up requirements for localised hydraulic improvements. More information will be shared with WCBC and residents as scheme proposals are developed. Gresford (Claypit Lane) This scheme is currently with our Capital Partners to finalise a solution, and again, more information will be shared with WCBC and residents as scheme proposals are developed. 11