Appendix-F-Potential-Growth-Areas
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F Potential growth areas The following tables provide a summary of information relating to flood risk for locations identified as potential strategic growth areas. Appendix F has been prepared based on the most up-to-date information concerning the proposed growth areas, at the time of preparing this SFRA. It also contains information on one additional area, where major development is planned. Each table is supported by corresponding interactive maps. These maps can be found by using the Appendix F Index Map and clicking on the corresponding square in the map. The interactive map for the area will then open in a separate PDF. The table also lists which maps relate to the proposed growth area. The supplied information relating to the proposed growth areas did not provide a defined boundary. Therefore, the interactive maps have a buffer, to cover the proposed growth areas and immediate surrounding land. F.1 AREA 1: Northern Gateway Proposed growth area (Northern Gateway) The proposed growth area is centred around the northern parts of the A42 and M1 in North West Leicestershire District and Charnwood Borough. The interactive maps ref: SFRA_F01 and SFRA_F02 relate to this proposed growth area. Fluvial Flood Risk The main fluvial flood risks to the proposed growth area are associated with the Black Brook, the Grace Dieu Brook, the Westmeadow Brook and the Diseworth Brook. However, the Flood Zones are narrow and confined throughout much of the proposed growth area. Flood Zones are comparatively wider at the confluence of the Black Brook and Grace Dieu Brook. Flood Zone 3b has not been identified along the watercourses in the proposed growth area. Further modelling may be required to identify Flood Zone 3b and the impacts of climate change, as part of site-specific Flood Risk Assessments. There are several, un-named watercourses in the proposed growth area which are not included in the Environment Agency’s Flood Zone 2 and 3 coverage. These watercourses primarily drain towards the Diseworth Brook, the Westmeadow Brook and the Black Brook, as well as an un- named watercourse to the west of the proposed growth area. Fluvial flood risk may be from one or more of these watercourses. Further modelling and investigation may be required to identify the Flood Zone coverage of these watercourses and the impacts of climate change, as part of site-specific Flood Risk Assessments. Notably, an un-named watercourse is shown to lead from East Midlands Airport towards the Diseworth Brook and has no Flood Zone coverage. Further modelling and investigation may be required to identify the Flood Zone coverage of these watercourses, if there is any significant interaction with the surface water network (e.g. around East Midlands Airport) and the impacts of climate change as part of a site-specific Flood Risk Assessment. In the proposed growth area, the Grace Dieu Brook is classed as a Main River. The Black Brook is classified as a Main River from downstream of Blackbrook Reservoir. All other watercourses in the proposed growth area are classified as ordinary watercourses. Appendix F Potential growth areas Final v1.0.doc I Surface Water Flood Risk The mapping shows surface water flood risk in the proposed growth area generally follows similar flow paths to watercourses. Due to the steep topography, much of the overland flow is directed towards low lying areas in the valleys of the watercourses and consequently, limited surface water ponding is shown outside of these valleys. One flow path follows a valley, from Harborough Pit Farm towards the Grace Dieu Brook. Another surface water flow route follows the flow path of an un-named watercourse, which leads from Spring Burrow Lodge in North West Leicestershire District. This flow path does not follow the route shown in the Detailed River Network (DRN) for its entire length; south of Fishpool Grange, it diverts and flows towards the Black Brook further downstream. Within the western part of Shepshed, covered by the proposed growth area, surface water is shown to pond on some of the local roads during in the 3.3% AEP event. Surface water is also shown to pond in isolated areas, on the higher ground, during the 0.1% AEP event. The mapping shows a notable area of surface water ponding, around the A512 and a place called “Ringing Hill” on the OS mapping, during the 0.1% AEP event. Groundwater Flood Risk The AStGW flooding mapping indicates that much of the proposed growth area is either within the <25% category or within the >= 25% <50% category. Areas within the >= 25% <50% category are found along the flow path of the Diseworth Brook (particularly in Diseworth), the Black Brook and the Grace Dieu Brook. Certain areas along the flow paths of the Black Brook and Grace Dieu Brook are also within the >= 50% <75% category. Reservoir Flood Risk The proposed growth area is shown to be at risk of flooding if the EMA Gimbro Ponds, the Central East Area Balancing Pond and / or the Blackbrook Reservoir were to fail. The EMA Gimbro Pond is located within the proposed growth area, the Central East Area Balancing Pond is located at East Midlands Airport and the Blackbrook Reservoir is located immediately upstream of the proposed growth area, partially within North West Leicestershire District. The consideration of the residual risk posed by these reservoirs should be considered as part of site- specific Flood Risk Assessments. Considering the proximity of these reservoirs to the proposed growth area, there would be very limited time, if any, to respond to a reservoir breach. Flood risk from other sources There are no canals in the proposed growth area. The Water and Sewerage Company which covers this proposed growth area is Severn Trent Water. The 2014 Charnwood Borough SFRA Update used Severn Trent Water’s DG5 register; according to this, Shepshed is prone to sewer flooding. Two records of sewer flooding have been recorded at the LE12 9 post-code area (Shepshed) in Severn Trent Water’s risk register. Previous and known flooding issues There are two historical flood records at Diseworth, recorded in November 2000 and November 2012. The November 2012 event was considered a result of fluvial flooding from the Diseworth Brook. One flood event was recorded at Belton in 1987. There are two historical flood records at Shepshed, recorded in August 2012 and June 2016. The records were taken from Fire and Rescue data and the source of flooding and magnitude of the event were not stated. Thus, these records may be isolated incidents. The proposed growth area is located within the 1977 flood extent of the Black Brook, in the Environment Agency’s Historic Flood Map. Appendix F Potential growth areas Final v1.0.doc II Changes to flood risk in the future Climate change is likely to: • Increase storm intensities. • Climate change may increase the depth, velocity or hazard of fluvial flooding • Climate change may also increase the extent, depth and frequency of surface water flooding Where detailed hydraulic models were supplied for use in the assessment, climate change modelling for the watercourses in study area was undertaken based on the new climate change guidance. Appendix H for the SFRA provides details on the detailed models used in the assessment. There is no climate change modelling covering watercourses within the proposed growth area. Developers should develop detailed hydraulic models as part of a site-specific Flood Risk Assessment and include climate change in the assessment. Current flood risk management infrastructure Watercourses in the proposed growth area are undefended. A Property Level Flood Protection scheme is proposed for Diseworth under Leicestershire County Council’s Local Flood Risk Management Strategy and as listed in the February 2017 Environment Agency Flood and Coastal Erosion Risk Management (FCERM) Programme. The proposed growth area is partially covered by the Environment Agency Flood Alert Areas: • River Trent in Derbyshire • Lower River Soar in Leicestershire • Loughborough Urban Watercourses. The proposed growth area is not covered by an Environment Agency Flood Warning Area. Potential for future flood risk management The potential growth area covers primarily rural land and a few urban settlements including Diseworth and parts of Shepshed. The mapping shows that: • Many of the watercourses in the proposed growth area flow towards the Diseworth Brook; this brook flows through the centre of Diseworth. • Parts of Diseworth are at risk of flooding from fluvial and / or surface water sources. • The Black Brook joins the Grace Dieu Brook at their confluence to the north-east of the proposed growth area; the Grace Dieu Brook then flows into Loughborough. • The northern part of Shepshed is at risk of flooding from fluvial sources and Loughborough is at risk from several sources, notably surface water for which there have been several recorded flood events attributed to this source. Diseworth is proposed to have a Property Level Flood Protection Scheme. Development in the potential growth area could provide opportunities to implement strategic solutions to improve flood risk in this area and downstream in Loughborough. One measure is the use of SuDS techniques, to ensure post-development runoff rates are at a manageable and appropriate level and to reduce the risk of development increasing flood risk downstream. Another measure is the creation of a flood storage area, to hold back flows and reduce the volume of water entering the Grace Dieu Brook. Strategic flood risk opportunities in this area may require cross-boundary partnership working with North West Leicestershire District Council and Charnwood Borough Council. Appendix F Potential growth areas Final v1.0.doc III Miscellaneous site information • The proposed growth area is: o not located within a Groundwater Source Protection Zone; o nearly entirely located within a Surface Water Nitrate Vulnerability Zone (proposed 2017 Nitrate Vulnerability Zone, ref S309), o is partially located within a Groundwater Nitrate Vulnerability Zone (proposed 2017 Nitrate Vulnerability Zone, ref G34); and, o is partially located within the sub-regional GI network.