www.metengineers.com Trustee’s of Mrs E Guthrie’s 1991 settlement Development at Racecourse Road East Ayton Scarborough Flood Risk Assessment And Drainage Strategy Ref-13686-5000 Revision No 00 November 2015 Professional, Innovative, Practical Solutions Land at Racecourse Road, East Ayton, Scarborough. Revision Record Report Ref: 13686-5000-00 FRA Rev Description Date Originator Checked Approved 00 Initial Report Nov 2015 AK This report is to be regarded as confidential The Trustee’s of Mrs E Guthrie’s 1991 Settlement. It is intended for your use only and may not be assigned. Consequently and in accordance with current practice, any liability to any third party in respect of the whole or any part of its contents is hereby expressly excluded. Before the report or any part of it is reproduced or referred to in any document, circular or statement and before its contents or the contents of any part of it are disclosed orally to any third party, our written approval as to the form and context of such a publication or disclosure must be obtained. Prepared For: Prepared By: Trustee’s of Mrs E Guthrie’s 1991 Met Engineers Limited Settlement Southgate House C/O Mathie Jamie Chartered Surveyors Pontefract Road Leeds West Yorkshire LS10 1SW Land at Racecourse Road, East Ayton, Scarborough. Contents Page 1.0 Introduction 1 1.1 Background 1 1.2 Regulatory Guidance 2 1.3 Information Sources 4 1.4 Geology 5 1.5 Hydrogeology & Hydrology 6 1.6 Groundwater Protection 6 1.7 Current Environment 9 1.8 Historical Notes 9 2.0 Flood Risks and Mitigation 10 2.1 Main River Flooding 11 2.2 Non Main River Flooding 13 2.3 Groundwater and Surface Water Flooding 14 2.4 Tidal Flooding 15 3.0 Run-off Assessment 16 3.1 Existing Site 16 3.2 Development Proposal 16 Land at Racecourse Road, East Ayton, Scarborough. 3.2.1 General Drainage Considerations 16 3.2.2 Proposed Foul Drainage 18 3.23 Proposed Surface Water Drainage 18 3.2.2 Sustainable Urban Drainage 18 3.3 Proposed Measures 20 3.4 Sequential Test 21 4.0 Conclusions & Recommendations 22 Land at Racecourse Road, East Ayton, Scarborough. Appendices Appendix 1 Site Location Appendix 2 Site Photographs Appendix 3 Indicative Flood Plain Map Appendix 4 Strategic Flood Risk Assessment Plans Land at Racecourse Road, East Ayton, Scarborough. 1.0 INTRODUCTION 1.1 Background i. We have been requested by The Trus M E G to undertake a Drainage Strategy and Flood Risk RunOff Assessment, for a parcel of land to the South of Racecourse Road on the Eastern limits of the Village of East Ayton near Scarborough. ii. The site is predominantly open agricultural land, and at the time of our site visit had recently been ploughed. iii. The site is roughly rectangular in shape, measuring around 2.18 Hectares, approximately 5.7 Kilometres South West of Scarborough City Centre at map reference 499439 484908. iv. The site has frontage access onto the public highway of Racecourse Road (A170)and Seamer Road (B1261)and is outlined on the enclosed location plan (Appendix 1) v. The nearest main watercourse to the site is the River Derwent, flowing in a southerly direction approximately 600m west of the site. vi. The site falls generally from the North East to the South West by approximately 8m. Highway boundary hedges to Racecourse Road and timber post and rail fence to Seamer Road form the North and south boundary respectively, the western boundary is again defined by Hedgerow to existing residential property with a BT Telephone Exchange in the south west corner to Seamer Road. There is no obvious boundary to the East. vii. The Northern part of the site is allocated within Scarborough Borough Councils (Draft) Local plan designated as residential allocation under policy HA29. viii. The objective of a Flood Risk Assessment is to demonstrate that a proposed development is sustainable in flood risk terms. This means that the development should not itself be at a significant risk of flooding or result in an increased flood risk elsewhere. The guidance given in The National Planning Policy Framework (NPPF) states that Local Authorities should adopt Proactive strategies at a local level through Strategic Flood Risk Assessments. Date November 2015 Page 1 Revision Number 00 Land at Racecourse Road, East Ayton, Scarborough. ix. As a consequence of NPPF, issued in March 2012, which refers to Flooding and Flood Risk, it is necessary to provide an assessment of the potential problems which are associated with: a. Permitting the Development. b. Potential risk of flooding from the watercourse and sewer network. c. Safety of occupants of the dwellings. d. Impact upon the local hydrological network. x. In the absence of a report, the Planning Authority are required to use the P P should refuse the application, unless there are grounds for not doing so. xi. In order to provide a Flood Risk Assessment, use has been made of the information contained at the offices of the Environment Agency, Yorkshire Water and Scarborough Borough Council. xii. The Environment Agency and Yorkshire Water have been consulted and their information and comments have been used in this report. 1.2. Regulatory Guidance i. National Planning Policy Framework (NPPF) along with the Technical Guidance replaces PPS25 and provides the regulatory framework and guidance for Planning Authorities in relation to Flood Risk issues for new developments. Any applications lodged with a Planning Authority will be considered in conjunction with this guidance and dependant on the nature and location of the application, the Planning Authority may request a Flood Risk Assessment as part of the Planning Application documents. ii. The Environment Agency (EA) are a Statutory Consultee to the Planning Authority in relation to Flood Risk issues. In addition, many Local Authorities have their own Internal Land Drainage Department which advice on Drainage Issues and work with the EA on Strategic issues. The Land Drainage Act 1991 provides a regulatory framework for this arrangement. iii. The Agency has provided a matrix for Local Planning Authorities, which provides F ‘ A T E Agency Standing advise Development and Flood Ri F tabulates the requirements relative to the scale of development and the predicted Date November 2015 Page 2 Revision Number 00 Land at Racecourse Road, East Ayton, Scarborough. Flood Zone. The assessment is required for all sites greater than 1Ha in Flood Zone 1, and all sites regardless of size in Flood Zones 2 & 3a. iv. The Environment Agency have undertaken a national study of flood risk across the whole of England and published flood maps covering the country. The maps can be viewed on the agencies website at www.environment- agency.gov.uk/whatsinmybackyard. Specific locations can be studied by searching either using a postcode or general location. A copy of the Flood Zone Map covering this location is attached in Appendix 5. v. The EA Flood maps identify 3 zones. vi. Flood Zone 1. This zone comprises of land with less than 1 in 1000 annual probability of river or sea flooding in any one year (<0.1%) vii. Flood Zone 2. This zone comprises of land assessed as having between a 1 in 100 and 1 in 1000 annual probability of river flooding (1%-0.1%) or between 1in 200 and 1in 1000 annual probability of sea flooding (0.5%-0.1%) in any one year. viii. Flood Zone 3. This zone comprises of land assessed as having a 1 in 100 year or greater annual probability of river flooding (>1%) or a 1 in 200 or greater annual probability of flooding from the sea (>0.5%) in any year. ix. Flood risks should consider the risk of flooding from all sources ie, tidal and river, surface water and flooding from land, groundwater, sewers and artificial sources, eg canals and reservoirs. x. The level of detail and complexity of a Flood Risk Assessment can vary considerably, dependant on the scale, nature and location of the planned development. EA guidance sets out the criteria for the level of information which should be included within the FRA. xi. According to the Environment Agencies Indicative Flood maps, the Application site falls within Flood Zone 1 and is greater than 1Hectare, therefore a site specific Flood Risk Assessment is required. xii. NPPF sets out criteria for vulnerability classifications which are based on the sensitivity of different forms of development. In accordance with NPPF, the intended M V xiii. The Sequential Test: In accordance NPPF LPA should apply the sequential test, to demonstrate that there are no available sites in the area with a lower risk of flooding. Date November 2015 Page 3 Revision Number 00 Land at Racecourse Road, East Ayton, Scarborough. xiv. The Exception Test: The Exception test is relevant if, following the application of the sequential test, it is not possible for the development to be located in zones of lower probability of flooding. The exception test criteria are detailed in NPPF. The test provides a method of managing flood risk while still allowing necessary development to occur. xv. Y W S A the standards for adoptable surface water and foul sewers. They also apply development control standards locally which are consistent with current best practice and Building Regulations. xvi. D - Y W to ensure that there is sufficient time for the company to fully assess the impact of development on their network and Treatment Facilities. This process also ensures that drainage strategies are acceptable in principle, prior to Planning Permission and helps avoid any objections from Yorkshire Water during the Planning Process. xvii. T F W M A change the way developers and Local Authorities approach the design and adoption of SuDS N SDS A B SAB SDS SAB SuDS designs and adopt the constructed drainage.