Strategic Flood Risk Assessment Level 1
The Senior Planner introduced the report which provided an update on work carried out by engineering and environmental consultants, JBA, on the Swale Borough Council Level 1 Strategic Flood Risk Assessment (SFRA). She explained that the SFRA was used as part of the evidence base for the Local Plan Review; and that SFRAs were required by the National Planning Policy Framework (NPPF), and would be used to inform the sequential approach to allocating development. Further clarification was being sought from the consultants, in liaison with the Environment Agency (EA) and Kent County Council (KCC) with regard to groundwater issues.
Members were invited to ask questions.
In response to a question about whether areas within a flood plain, with appropriate mitigation measures, could be brought forward for consideration, the Senior Planner explained that the NPPF sought to direct new development away from flood risk areas, but these areas could be developed by going through the process of a detailed Sequential Test and an Exception Test. There would need to be overriding reasons to build on a flood plain, that safe access, egress and resilience would need to be proved and developments would need to demonstrate, through Flood Risk Assessments (FRAs), that they would not increase flood risk elsewhere. She added that it was not national policy to build on a flood plain. The Member referred to paragraph 3.3 in the report and suggested that developers be given the option to potentially build on flood plain areas, subject to mitigation measures that the developers would put in place. The Senior Planner referred to Faversham Creek Neighbourhood Plan and explained that the flood plain area here was confined, and so not too difficult to demonstrate that safe egress could be achieved, and so in this case, the Environment Agency (EA) agreed that the flood designation could be changed.
In response to a question, the Senior Planner explained that once the SFRA was on the website it would be clearly labelled as ‘2019’. This would enable this study to be distinguished from any subsequent updates which would need to be referenced in FRAs.
A Member asked whether the UK Climate Projections 18 (UKCP18) projections had been taken into account in the report. The Senior Planner explained that 2018 updates from UKCP18 had not yet been included in the EA modelling and were therefore not included in the SFRA. This approach had been discussed with the EA and agreed as appropriate as the SFRA was using the best available evidence. The Senior Planner said that developers needed to use the most up-to-date figures and then do their own modelling which should include the UKCP18 projections. A Level 2 report would also likely use the UKCP18 projections. The EA had advised that the most significant impact was the frequency of flooding.
In response to a question, the Senior Planner clarified that Appendix C on page 137 of the report indicated the existing flood zones, and Appendix D indicated the impact of climate change. In response to a question, she explained that the cliffs in the north of the Isle of Sheppey helped to reduce the impact of tidal flooding, although coastal erosion was a significant issue in this area.
A Member asked whether aquifers were considered within the report? The Senior Planner said that these could be dealt with in individual flood risk assessments, where relevant, and the impact on aquifers was something that was within the remit of the EA and she referred to page 97 of the report which gave details of groundwater source protection zones. The Member considered that the many natural springs in the Borough should also be included in the study. The Senior Planner explained that the springs were often difficult to locate at a strategic scale. She explained that some smaller water courses were also not mapped because they were not deemed significant enough, but that individual flood risk assessments would be expected to account for all water courses and flooding from all sources. The Senior Planner agreed to look into reported surface water flooding near the Stones Farm Development, Bapchild, in response to the Member’s concerns.
A Member referred to page 135 of the report and considered underground water courses should also be included, as they could be a potential issue for developers. The Senior Planner explained that it was not always possible to map groundwater accurately at a strategic scale, in particular in Swale where the aquifer was commonly chalk without defined underground watercourses. She explained that following discussion with KCC and the EA, JBA had been asked to clarify when developers would be required to look in detail at groundwater within their FRAs.
In response to a question, the Senior Planner advised that it was the developers responsibility to upgrade flood defences on any land they were developing. She confirmed that, as part of the Sequential Test, the Strategic Housing Land Availability Assessment (SHLAA) sites would be looked at to assess the risk of flooding, and if not enough land could be allocated in Flood Zone 1, then Flood Zone 2 would have to be looked at.
A Member considered other areas should be looked at, beyond Flood Zone 1, and to have the option to do that. The Senior Planner explained the NPPF policy which directed development to land least likely to flood and that sites where no mitigation measures were required would be considered first. She said that building safely in the floodplain, without increasing risk to others was a complicated process, and the ability to establish infrastructure, such as electricity and other services, including safe access and escape, would need to be taken into consideration and agreed with the EA.
A Member suggested that Milton Creek be regenerated. The Senior Planner acknowledged this, but pointed out that as this was a larger area than Faversham Creek, there could be more risk. The Local Plan Manager asked that Members put forward preferred areas/sites for regeneration in the Borough, in order to assess the potential extent of review work.
A visiting Member referred to anecdotal evidence and whether the onus was on the planners to mitigate this. The Senior Planner said that it would be the responsibility of the developer to address flood risk. The Member asked whether the developers would be scrutinised to ensure they had adhered to the correct procedures. The Senior Planner explained that they would have to complete a flood risk assessment, and that most anecdotal evidence would have got to KCC and the EA in any case. The Head of Planning Services explained that the case officer would challenge the agencies involved with any anecdotal evidence, however few in number they were.
A Member referred to page 143 in the report and to the amount of land with ground water levels between 0.5 metres and 5 metres below the ground surface. The Senior Planner explained that there were discussions with the consultants on this matter, and said this was a broad strategic look at the land.
A Member considered ground water and surface water drainage were issues, and said that often developers did not take responsibility for these. The Head of Planning Services agreed to look into this further and report back to Members on the legal issues involved.
A Member requested some guidance on building on flood plains/zones, as a Supplementary Planning Document (SPD). The Local Plan Manager suggested we should look into whether it would be appropriate to bring forward such guidance.
The Chairman moved the following additional recommendation: That an SPD on flood risk measures be considered. This was seconded by the Vice-Chairman. On being put to the vote this was agreed.
(1) That the findings of the SFRA be noted and it be agreed that it should be used as part of the evidence base for the Swale Local Plan Review.
(2) That it be agreed that mapping from the SFRA should be incorporated into the interactive mapping on the Swale Borough Council website.
(3) That an SPD on flood risk measures be adopted.
- SFRA Rpt for Local Plan Panel 281119, item 379. PDF 87 KB
- APPENDIX I MAIN REPORT Swale Level 1 Strategic_Flood_Risk_Assessment, item 379. PDF 10 MB
- 2019s0345 - Appendix A - Historic Flooding - District (v2), item 379. PDF 5 MB
- 2019s0345 - Appendix B - Watercourses - District (v2), item 379. PDF 5 MB
- 2019s0345 - Appendix C - Flood Zones and Surface Water Functional Flood Zones- District - A2 - (v2), item 379. PDF 2 MB
- 2019s0345 - Appendix D - Climate Change - District (v2), item 379. PDF 5 MB
- 2019s0345 - Appendix E - Risk of Flooding from Surface Water - District (v2), item 379. PDF 6 MB
- 2019s0345 - Appendix F - Groundwater - District (v2), item 379. PDF 6 MB
- 2019s0345 - Appendix G - Reservoir Inundation - District (v2), item 379. PDF 5 MB
- 2019s0345 - Appendix H.1 - Flood Defences - District (v2), item 379. PDF 5 MB
- 2019s0345 - Appendix H.2 - EA Flood Defences Types - Tiles (v2), item 379. PDF 8 MB
- 2019s0345 - Appendix H.4 - EA Flood Defence Conditions - Tiles (v2), item 379. PDF 8 MB
- 2019s0345 - Appendix I - Breach Locations and Extents - District (v2), item 379. PDF 5 MB
- 2019s0345 - Appendix J - Flood Warning and Alert Area - District (v2), item 379. PDF 5 MB
- 2019s0345 - Appendix K - Site Screening (v2), item 379. PDF 524 KB
- 2019s0345 - Appendix L - Potential areas for flood defence improvement (v2), item 379. PDF 6 MB