Draft Core Strategy (incorporating Preferred Options) October 2010

Draft Core Strategy (incorporating Preferred Options)

Flood Risk

12.17 As described above, climate change is likely to mean wetter winters in South Somerset and potentially more frequent flooding. National planning policy[1] makes clear that flood risk should be taken into account at all stages in the planning process; inappropriate development should be avoided in areas of flood risk, and development should be directed away from areas with a medium and high risk of flooding.

12.18 South Somerset’s Strategic Flood Risk Assessment (SFRA) highlights areas at risk of flooding from rivers, and also identifies flooding incidents from all sources (e.g. rivers, surface water, groundwater flooding) that have occurred in the past. Some areas in and around Yeovil are within Flood Zone 3 (high flood risk), as are parts of many of the Market Towns and Rural Centres in South Somerset (particularly at Langport / Huish Episcopi and Ilchester), although in most cases the area affected is small. The Proposals Map Inset Plans show, in relation to the upper levels of the settlement hierarchy, areas of high (flood zone 3) and medium (flood zone 2) flood risk where national policy prescribes the sequential test and, where necessary, the exception test that should be applied in these areas before development is considered acceptable.

12.19 Surface water flooding also affects most of these settlements, particularly Yeovil. Sustainable Urban Drainage Systems (SUDS) are encouraged as they mimic natural processes by slowing down the volume and rate of run off following heavy rainfall, therefore reducing the risk of surface water flooding. The SFRA states that there is a relatively high potential for SUDS in South Somerset due to the permeable underlying geology. The Environment Agency produce Catchment Flood Management Plans (CFMPs) to identify strategic flood risk management policies in river catchments over the long term (50-100 years). The River Parrett CFMP covers most of South Somerset, and states that, in the future the main problems in Yeovil may be related to higher intensity summer storms that overwhelm the local sewers and smaller streams.

1. PPS 25: Development and Flood Risk, revised in 2010. [back]