Head of Development Services
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DIRECTOR OF DEVELOPMENT SERVICES REPORT TO CABINET 28th June 2006 FLOOD DEFENCE STATEMENT & DRAINAGE ISSUES 1.0 PURPOSE OF REPORT 1.1 The purpose of this report is to inform Members of changes that have occurred to a variety of drainage functions and to seek approval for the Flood Defence Statement and for certain powers to be delegated to officers. This report briefly describes these issues. 2.0 INTRODUCTION - THE ROLE OF THE VARIOUS AGENCIES 2.1 Thirty years ago, local authorities were responsible for most drainage matters. Arrangements are now very different as a result of national legislation. The Environment Agency (EA) is now the major Land Drainage Authority, leaving a residual role for the local authorities. Yorkshire Water are now responsible, as the Sewerage Authority, for the public sewerage system and for water supply (other than for the south-east corner of the City, which has Severn-Trent as the water supplier). Regrettably this fragmentation has created a situation where the public are often unclear about the responsibilities and liabilities. 2.2 The Environment Agency is the country’s largest non-departmental public body. It is governed locally by the Yorkshire Regional Flood Defence Committee (YRDFC), which includes a representative Member from Sheffield City Council. The YRFDC has a 2006/07 planned expenditure of around £40m, although over both the last and forthcoming decades, as a result of priority needs elsewhere in the region, less than 1% of their expenditure on flood defence schemes was/will be within Sheffield. 2.3 The EA are the Land Drainage Authority for Main Rivers; the full list of Main Rivers is given in Appendix 2. The EA maintain a flood risk map for these rivers, which is available for public inspection on their web site. In addition they operate a flood warning system for the most vulnerable properties; in Sheffield this principally applies to properties around the Sheaf Gardens area south of Granville Square. 2.4 Within the The City CouncilTransport & Highways Division of Development Services, has responsibility for the Council's roles as the Land Drainage Authority and the Highway Authority. Street Force provides technical and management roles for maintenance and improvement works on highway and other drainage works. The Environmental Services Unit (ERS, D.E.L.) has separate powers with regard to matters of private drainage and nuisances. 2.5 The Council maintains records showing the known watercourse culverts and highways drains, but it does not maintain records of private drainage around property. 3.0 BACKGROUND 3.1 Flooding can occur from many differing sources, the main national concern being the major fluvial flooding from rivers, which overtop their banks after periods of extreme rainfall. There have been several high profile floods in England over recent years, such as the 2004 Carlisle flood, which is estimated to have caused £450million worth of damage. 3.2 Sheffield is fortunate in that the City does not tend to suffer from widespread fluvial flooding due to the topography and also, in part, due to the attenuation given to storm flows by the impounding reservoirs in the Upper Don valleys. 3.3 The EA web site shows the areas at risk of fluvial flooding from main rivers and this includes about 5,000 properties in Sheffield at risk from a 1 in 100 year event. British Land (Meadowhall Centre) has recently invested heavily in flood defence as a necessity for insurance purposes and their consultants are currently looking closely at the flood risk along the Lower Don Valley in order to inform a flood risk strategy for possible future development. 3.4 Whilst flooding from the larger main rivers obviously carries the most widespread threat, Sheffield suffers regular flooding problems at many locations due to lack of capacity and blockages in many of the smaller watercourses, particularly with regard to the culverted lengths through urban development. Inevitably culverts, many laid over 100 years ago, are inadequate to take the peak flows generated and debris can create blockages, especially at culvert entrances. There are several other sources of flooding, both foul and surface water related, which are regularly reported around the City. These include inadequate sized or blocked drains and sewers, surface water run-off, ground water springs, water supply leaks and highway gully problems. 3.5 The Director of Street Force made detailed reports on the recent improvements in gully cleaning to the Council’s Culture, Economy and Sustainability Scrutiny Board during 2005. 4.0 FLOOD DEFENCE STATEMENT 4.1 In accordance with the requirements of the High Level Targets (HLTs) set by Department for the Environment, Food & Rural affairs (Defra), the City Council is required to adopt a Flood Defence Statement. Officers have produced a written statement of flood defence policy, which is to a standard format for local authorities. It largely reiterates the existing policies of the Council. This statement has recently been updated and is reproduced in full in Appendix 1. The key features within this statement are: (i) the provision of an adequate and environmentally sound approach to flood defence matters, (ii) playing a positive role in the management of flood risk, including a strategic flood risk assessment, (iii) maintaining suitable liaison with the Environment Agency, and (iv) discouraging inappropriate development. 4.2 The statement forms an over-arching policy, which ties in with the Council’s detailed policies and procedures that are described briefly in the next section. The statement has to be sent to both Defra and to the Environment Agency and made available for public reading; it is intended to put the statement on the Council’s website. 5.0 PLANNING & DEVELOPMENT CONTROL 5.1 Planning Policies concerning the drainage element of the development control process have evolved over time and there is now a much greater emphasis on flood risk in planning decisions. The Council has a range of policies for the protection of water features, including the promotion of green corridors along watercourses and the presumption against new culverting of streams. These policies, listed in Appendix 4, are part of the current 1998 Urban Development Plan (UDP) and are being reviewed as part of the proposed Sheffield Development Framework (SDF), which will replace the UDP. 5.2 Climate change and increasing urban densities are creating a significant rise in the number of major flooding events nationally. The Government is therefore requiring a more precautionary approach to flood risk management. The EA now consider the implications of a 1 in 100 year flood event. Planning Policy Guide 25 (PPG25) gives the current national advice on the drainage requirements for planning approvals, although this is due to be superseded later this year by Planning Policy Statement 25 (PPS25), which will bring in stricter controls. The Environment Agency will become a statutory consultee for many planning applications where there is a flood risk, although in Sheffield the planning officers already undertake such consultations. One of the major changes being introduced is likely to be when the Local Planning Authority is minded to grant approval against the wishes of the EA; it will then be necessary to refer applications to the Secretary of State prior to determination. In areas of potential flood, developers are already required to provide a flood risk assessment (FRA) with their planning application. In line with the requirements of the HLTs and PPS25, the Council have commissioned consultants to undertake a Strategic Flood Risk Assessment. 5.3 Planning policies now require more control on the discharge of surface water from sites. This is necessary in order to minimise the adverse effects that high discharge rates can have on the receiving watercourses or sewers. Various conditional approvals are utilised depending on whether the site is “greenfield” or “brownfield”. The use of sustainable urban drainage techniques (SUDs) and rainwater harvesting are all promoted, where feasible. 6.0 FINANCIAL IMPLICATIONS 6.1 Whilst there are no financial implications arising from the contents of this report, there are 2 financial issues worthy of note. 6.2 The majority of funding to the EA used to be via local authority levies, but the system changed in 2004 such that the main funding is now direct grant from Central Government, supplemented by a smaller local levy. Government reimburses local authorities for the levy funding via the Formula Spending Share (FSS), but this is 1 year in arrears. Therefore, any increase in the levy has to be met as a subsidy by the Councils. Provision has been made in the Corporate Budget for Sheffield’s levy contribution, which in 2006/07 rises from £33,334 to £48,739, giving an increased payment of £15,405. The total YRFDC local levy rises from £341,961 in 05/06 to £500,000 in 2006/07. 6.3 The length of Main Rivers has been recently increased by the transfer of Critical Ordinary Watercourses, to give the EA more control. In Sheffield the length increased in 2004 from 67km to 94km, as detailed in Appendix 2. Defra has decided to transfer to the EA an extra £5m and it is understood that this will be reflected as a reduction in the FSS of the relevant local authorities. For Sheffield, this reduction is estimated at £80,000. 7.0 PUBLICATIONS & CONSULTATIONS 7.1 A list of available documents for reference is given in Appendix 5. There have been several national consultations on drainage matters over recent years to which Council staff have provided input. A list of the current Drainage information sheets is given in Appendix 3. 8.0 CLIMATE CHANGE 8.1 It is generally accepted that climate change will lead to an increase in the percentage of annual rainfall that occurs as heavy storms in winter.