Strategic Flood Risk Assessment - South Worcestershire ...

Zone 1Zone 2Zone 3aZone 3bTable 4-1: Flood Zone descriptionsProbability Description Suitable Development*LowMediumHighFunctionFloodplainThis zone comprises land assessedas having a less than 1 in 1000annual probability of river or seaflooding in any year (1.0%) or a greater than 1 in 200annual probability of flooding fromthe sea (>0.5%) in any year.This zone comprises land wherewater has to flow or be stored intimes of flood. SFRAs shouldidentify this Flood Zone (land whichwould flood with an annualprobability of 1 in 20 (5%) or greaterin any year or is designed to flood inan extreme (0.1%) flood, or atanother probability to be agreedbetween the LPA and theEnvironment Agency, includingwater conveyance routes.All uses of landWater compatible, lessvulnerable and more vulnerableuses of land and essentialinfrastructure are appropriate.The highly vulnerable uses areonly appropriate if the ExceptionTest is passed.Water compatible and lessvulnerable uses of land areappropriate.More vulnerable and essentialinfrastructure should only bepermitted if the Exception test ispassed.Highly vulnerable uses shouldnot be permitted.Water compatible and essentialinfrastructure that has to bethere is permitted.Essential infrastructure shouldpass the Exception Test and bedesigned and constructed tomeet a number of flood riskrelated targets.Less vulnerable, morevulnerable and highlyvulnerable uses should not bepermitted.The preference when allocating land is, whenever possible, to place all new development onland in Zone 1. Since the zones identify land that is not reliant on flood defences, placingdevelopment on Zone 1 land means that in future there is no commitment to spending money onflood banks or flood alleviation measures and not committing future generations to costly longterm expenditure that would become increasingly unsustainable as the effects of climate changeincrease. However, the runoff from development on Zone 1 land can potentially cause anincrease in the probability of flooding to existing downstream development. Information in theSFRA should be used to address this issue.4.2.2 Sub-divisions of Flood Zone 3 in South WorcestershireNPPF Technical Guidance, Table 1 defines Flood Risk Zones 3a (high probability) and 3b(functional floodplain). The latter can be defined as the 1 in 20-year return period flood, or atanother probability to be agreed between the LPA and the Environment Agency, including waterconveyance routes.For the South Worcestershire area, the LPAs and the Environment Agency have agreedon three sub-divisions of Flood Zone 3 for the major urban areas (Worcester, DroitwichSpa, Evesham, Pershore, Tenbury Wells and Upton upon Severn) as defined below:2012s5947 S Worcestershire Level 2 SFRA Update FINAL Report v1.0.doc 24