FLOOD RISK ASSESSMENT 11-4

Transcription

1 FLOOD RISK ASSESSMENT 11-4

2 Strathy Wood Wind Farm - Flood Risk Assessment Final Report January 2012 Atmos Consulting Ltd Rosebery House 9 Haymarket Terrace Edinburgh EH12 5EZ

3 JBA Office JBA Consulting Port Neuk 1 Longcraig Road South Queensferry EH30 9TD Revision History Revision Ref / Date Issued Amendments Issued to Site Visit Report - Draft / - Lucy Parker 14 October 2011 Site Visit Report - Draft v2 / Amendments following Lucy Parker 31 October 2011 review - s of 17 Oct & 26 Oct 2011 Flood Risk Assessment - Draft / Addition of hydraulic Lucy Parker 21 December 2011 modelling and conclusions Flood Risk Assessment - Final / 10 January 2012 Amendments following comments on Draft Report Lucy Parker Flood Risk Assessment - Final / 16 January 2012 Contract Minor amendments following comments Lucy Parker This report describes work commissioned by Atmos, on behalf of E.ON, through Purchase Order No. POR Atmos representative for the contract was Lucy Parker. Caroline Anderton, Angus Clark and Nicola Buckley of JBA Consulting carried out this work. Prepared by... Nicola Buckley BSc MSc Analyst Reviewed by... Caroline Anderton BSc MSc CEnv CSci MCIWEM C.WEM Principal Analyst Purpose This document has been prepared as a final report for Atmos Consulting Ltd. JBA Consulting accepts no responsibility or liability for any use that is made of this document other than by the Client for the purposes for which it was originally commissioned and prepared. JBA Consulting has no liability regarding the use of this report except to Atmos Consulting Ltd. 2011s Strathy Wood FRA - Final Report.doc

4 Acknowledgements JBA would like to thank Andy Low of SEPA for supplying gauge data. Copyright Jeremy Benn Associates Limited 2012 Carbon Footprint 239g A printed copy of the main text in this document will result in a carbon footprint of 239g if 100% post-consumer recycled paper is used and 304g if primary-source paper is used. These figures assume the report is printed in black and white on A4 paper and in duplex. JBA is aiming to achieve carbon neutrality. 2011s Strathy Wood FRA - Final Report.doc

5 1 Introduction Terms of Reference Reporting Guidelines Flood Risk Assessment Site Description and Details Historical Flooding SEPA Flood Map Existing Flood Alleviation Measures Hydrology Hydraulic Modelling Watercourse Crossings Flood Risk Outwith the Site Impact of the Development on Fluvial Morphology Changes in Surface Runoff Access and Egress Conclusions and Recommendations Appendices A Photographs s Strathy Wood FRA - Final Report.doc

6 List of Figures Figure 2-1: Site Location Plan... 2 Figure 2-2: Plan of the River Strathy Catchments... 3 Figure 2-3: Plan of the Sub-catchments... 4 Figure 2-4: Hydraulic Model Geometries... 8 Figure 2-5: Long Section of The Uair Showing Different Downstream Boundary Conditions... 9 Figure 2-6: Modelled 200 Year Plus Climate Change Flood Outlines Figure 2-7: Watercourse Crossings within Site Boundary Figure 2-8: Photograph of the Existing Bridge on The Uair Figure 2-9: Model Cross Section of the Existing Bridge on The Uair Figure 2-10: Model Cross Section of Proposed Bridge on The Uair (Option a) Figure 2-11: Model Cross Section of Proposed Bridge on The Uair (Option b) Figure 2-12: Model Long Section on The Uair Showing Different Bridge Options Figure 2-13: New Crossing of the Strathy Option Locations Figure 2-14: Model Cross Section of Proposed Bridge over the River Strathy (Location 1 on Embankment) Figure 2-15: Model Cross Section of Proposed Bridge over the River Strathy (Location 1 on Piers) Figure 2-16: Model Long Section on the River Strathy Showing Bridge Options (Location 1) Figure 2-17: Model Cross Section of Proposed Bridge over the River Strathy (Location 2 on Embankment) Figure 2-18: Model Cross Section of Proposed Bridge over the River Strathy (Location 2 on Piers) Figure 2-19: Model Long Section on the River Strathy Showing Bridge Options (Location 2) Figure 2-20: Model Cross Section of Proposed Bridge over the River Strathy (Location 3 on Embankment) Figure 2-21: Model Cross Section of Proposed Bridge over the River Strathy (Location 3 on Piers) Figure 2-22: Model Long Section on the River Strathy Showing Bridge Options (Location 3) Figure 2-23: Model Cross Section of Proposed Bridge over the River Strathy (Location 4 on Embankment) Figure 2-24: Model Cross Section of Proposed Bridge over the River Strathy (Location 4 on Piers) Figure 2-25: Model Long Section on the River Strathy Showing Bridge Options (Location 4) Figure 2-26: Model Cross Section of Proposed Bridge over Tributary Figure 2-27: Model Cross Section of Proposed Bridge over Tributary Figure 2-28: Watercourse Crossings Outwith the Site Boundary Figure 2-29: Flood Risk Receptor Locations s Strathy Wood FRA - Final Report.doc

7 Photograph 1: River Strathy Looking Upstream from Section Photograph 2: River Strathy Looking Downstream from Section Photograph 3: River Strathy Looking Downstream from Section Photograph 4: River Strathy Looking Downstream from Section Photograph 5: River Strathy Looking Upstream from Section Photograph 6: River Strathy Looking Upstream from Section Photograph 7: River Strathy Looking Downstream from Section Photograph 8: River Strathy Looking Across from Right Bank at Section Photograph 9: River Strathy Looking Downstream from Right Bank at Section Photograph 10: River Strathy Looking Upstream from Section Photograph 11: River Strathy Looking Downstream from Section Photograph 12: River Strathy Looking Downstream from Left Bank at Section Photograph 13: River Strathy Looking Downstream from Right Bank at Section Photograph 14: River Strathy Looking Across from Right Bank at Section Photograph 15: River Strathy Looking Downstream from Section Photograph 16: River Strathy Looking Across from Left Bank to Uair Confluence Photograph 17: River Strathy Looking Downstream from Section Photograph 18: River Strathy Looking Downstream from Section Photograph 19: River Strathy Looking Downstream from Section Photograph 20: River Strathy Looking Downstream from Section Photograph 21: The Uair Looking Downstream from Section Photograph 22: Upstream Face of Existing Bridge over The Uair at Section Photograph 23: Looking Downstream to the Existing Bridge over The Uair at Section Photograph 24: The Uair Looking Downstream to its Confluence with the River Strathy Photograph 25: Tributary 1 Looking Downstream from Section Photograph 26: Tributary 1 Looking Downstream from Section Photograph 27: Tributary 1 Looking Downstream from Section Photograph 28: Tributary 2 at Section Photograph 29: Tributary 2 Looking Downstream from Section Photograph 30: Tributary 2 Looking Upstream from Section Photograph 31: Tributary 2 Looking Downstream from Section Photograph 32: Tributary 2 Looking Downstream from Section List of Tables Table 2-1: Catchment Descriptors for the River Strathy at Strathy Bridge... 5 Table 2-2: Gauge Information - River Strathy at Strathy Bridge (96003)... 5 Table 2-3: Parameters of QMED Adjustment for River Strathy Flow Estimations... 6 Table 2-4: Flood Growth Factors... 6 Table 2-5: Peak Flow Estimates for the River Strathy... 6 Table 2-6: Peak Flow Estimates for the Sub-catchments s Strathy Wood FRA - Final Report.doc

8 Table 2-7: Sensitivity Analysis Results... 8 Table 2-8: Existing and Proposed Watercourse Crossings within Site Boundary Table 2-9: Existing Watercourse Crossings within Site Boundary Table 2-10: Modelled Water Levels on The Uair for Different Bridge Options Table 2-11: New Crossing of the Strathy Option Locations Table 2-12: Modelled Water Levels on the River Strathy for Different Bridge Options (Location 1) Table 2-13: Modelled Water Levels on the River Strathy for Different Bridge Options (Location 2) Table 2-14: Modelled Water Levels on the River Strathy for Different Bridge Options (Location 3) Table 2-15: Modelled Water Levels on the River Strathy for Different Bridge Options (Location 4) Table 2-16: New Crossing Over the River Strathy Optioneering Table 2-17: Watercourse Crossings Outwith the Site Boundary - Photographs Table 2-18: Main Flood Risk Receptors Abbreviations ALTBAR... Mean catchment altitude (m above sea level) AMAX... Annual Maximum BFIHOST... Base Flow Index estimated from soil type BHS... British Hydrological Society DPLBAR... Index describing catchment size and drainage path configuration DPSBAR... FEH index of mean drainage path slope FARL... FEH index of flood attenuation due to reservoirs and lakes FEH... Flood Estimation Handbook HEC-RAS... Hydrologic Engineering Center River Analysis System (developed by the US Army) JBA... JBA Consulting Engineers & Scientists maod... metres Above Ordnance Datum NGR... National Grid Reference NRFA... National River Flow Archive OS... Ordnance Survey PROPWET... FEH index of proportion of time that soil is wet QMED... Median Annual Flood (with return period 2 years) SAAR... Standard Average Annual Rainfall (mm) SEPA... Scottish Environment Protection Agency SPRHOST... Standard percentage runoff derived using the HOST classification URBEXT... FEH index of fractional urban extent 2011s Strathy Wood FRA - Final Report.doc

9 1 Introduction 1.1 Terms of Reference E.ON Climate and Renewables Developments Ltd (E.ON) propose to develop land to the south of Strathy in Caithness and Sutherland. The development will require the construction of new river crossings and part of the site lies within SEPA's Indicative River and Coastal Flood Map (Scotland); as such a more detailed assessment of flood risk, specific to the site, is required. The study is necessary to meet the requirements of Scottish Planning Policy, February 2010 (SPP) 1 and SEPA Policy The study comprised the following: Site walkover survey Consultation with SEPA and Highland Council The derivation of peak flows for several local watercourses The construction of hydraulic models on the River Strathy, The Uair and two unnamed tributaries of The Uair The modelling of potential bridge options over the River Strathy, The Uair and two unnamed tributaries of The Uair Advise on watercourse buffer zones Determine pre- and post-development runoff rates and SUDs volumes The consideration of option feasibility for the mitigation of flood risk The analysis of results and preparation of a report to meet the requirements of Scottish Planning Policy (SPP) and SEPA protocol. 1.2 Reporting Guidelines This Flood Risk Assessment is consistent with the reporting requirements detailed within SEPA s Technical Flood Risk Guidance for Stakeholders 3 which supersedes Annex B of SEPA Policy The aim of this document is to ensure that relevant information is presented in a clear format that can be reviewed by the Planning Authority and SEPA and is consistent with SPP 2. 1 Scottish Planning Policy, February Scottish Executive. 2 Scottish Environment Protection Agency Policy No. 41: A SEPA-Planning Authority Protocol, Development at Risk of flooding: Advice and Consultation, Version 1.0. September SEPA Technical Flood Risk Guidance for Stakeholders, Version 6, August flooding.aspx 2011s Strathy Wood FRA - Final Report.doc 1

10 2 Flood Risk Assessment 2.1 Site Description and Details E.ON Climate and Renewables Developments Ltd (E.ON) are proposing the development of an onshore wind farm within an area to the south of Strathy in Caithness and Sutherland. The indicative site boundary is shown within Figure 2-1, with the site referred to herein as 'Strathy Wood'. Figure 2-1: Site Location Plan The main watercourse passing through the site is the River Strathy, which passes through the site from the west to the north. The Uair converges with the River Strathy towards the downstream extent, and a number of additional small tributaries are also present within the area. 2.2 Historical Flooding A review of the BHS Chronology of Historical events, the Internet and the National Library of Scotland (NLS) Licence Digital Collections Archive of the Scotsman Newspaper ( ) did not result in any records of flooding in the vicinity of the site. 2.3 SEPA Flood Map SEPA s flood map is a strategic broad scale tool developed by SEPA for use in assessing flood risk. The River Strathy and Uair are covered by SEPA s Indicative River and Coastal Flood Map (Scotland). Several unnamed watercourses are however too small (catchment areas less than 3km 2 ) to have been covered during SEPA s flood mapping study. Within the study boundary this includes the two unnamed tributaries of the Uair, the Alltan na' Main and the unnamed tributary of the River Strathy (located to the south of the site). 2011s Strathy Wood FRA - Final Report.doc 2

11 2.4 Existing Flood Alleviation Measures There are no formal flood prevention or protection measures present in the immediate vicinity of the site. 2.5 Hydrology Flow estimates were undertaken at eight different locations within the catchment to inform the flood risk assessment. The flow estimation locations are detailed below and their catchments are shown graphically within Figure 2-2 and Figure 2-3. River Strathy Catchments: Catchment 1 (C1) - River Strathy at Strathy Bridge Catchment 2 (C2) - River Strathy downstream of The Uair confluence Catchment 3 (C3) - River Strathy upstream of The Uair confluence Sub-catchments: Catchment 4 (C4) - The Uair Catchment 5 (C5) - The Uair Sub-Catchment A Catchment 6 (C6) - The Uair Sub-catchment B Catchment 7 (C7) - Altan na' Main (to culvert beneath track) Catchment 8 (C8) - Unnamed Upper Catchment (to culvert beneath track) Figure 2-2: Plan of the River Strathy Catchments 2011s Strathy Wood FRA - Final Report.doc 3

12 Figure 2-3: Plan of the Sub-catchments Catchment Characteristics The hydrological catchment of the River Strathy at Strathy Bridge has an area of approximately 121 km 2. The catchment is orientated south to north and drains a remote area of northern Scotland. Land use within the catchment is dominated by heath and moorland, with sheep farming and forestry the predominant land uses. The area is designated a special area of conservation (SAC) for peat. Since the 1970s there has been extensive afforestation within the catchment and forest plantations now represent a significant area (c.25%). There are numerous small lochs within the catchment, which are likely to have an attenuation effect. The FEH CD ROM has a FARL value of for the catchment, which is representative of the storage effect that these lochans may have. The main tributary of the River Strathy is 'The Uair', which converges with the River Strathy to the northeast of Braerathy Lodge. The Uair is fed by numerous small tributaries and hill lochs that flow over open heathland. The catchment has a low percentage of forestry, with the predominant land use being open moorland/heath. The Uair has its source on the northeastern flanks of Cnoc nan Tri-chlach, which flows in to Loch Crocach approximately 15 km upstream of the confluence of The Uair with the River Strathy. A small percentage of flow from the upper portion of The Uair is thought to leave the catchment and flow into the Halladale catchment. Ordnance Survey mapping shows this occurs in two places in the vicinity of Loch nam Breac; at a sluice at the southern end of the loch, and where a stream bifurcates approximately 800 m upstream of the loch. Flow lost from the catchment is not thought be significant enough to affect the hydrological estimates. Geologically the River Strathy catchment predominantly consists of metamorphic migmatitic rocks from the moine supergroup; these represent approximately 80%. A fault runs north to south through the catchment which the River Strathy follows for its last 10 km before flowing into the North Sea. At the northern end of the catchment on the western side of the fault there is an area of Proterozoic Gneiss which represents approximately 10% of the catchment geology. To the east of the fault there is an area of Old Red Sandstone from the mid Devonian period of geological time; there are also small outcrops of this in the south of the catchment. These bedrock formations are overlain (c. 95%) with superficial deposits of till, alluvium and peat. 2011s Strathy Wood FRA - Final Report.doc 4

13 The catchment descriptors for the River Strathy at Strathy Bridge are summarised within Table 2-1. Table 2-1: Catchment Descriptors for the River Strathy at Strathy Bridge AREA (km 2 ) SAAR (mm) 1090 FARL SAAR (mm) 1110 PROPWET 0.60 URBEXT ALTBAR (m above sea level) 161 URBEXT BFIHOST FPEXT DPLBAR (km) FPDBAR DPSBAR (m/km) 58.1 FPLOC SPRHOST (%) Hydrometric Data Gauged data is collected on the River Strathy at Strathy Bridge (station number 96003); located within the study reach at OS NGR NC This gauge is present within the HiFlows-UK database 4. There are 25 years of data available for the gauge, with the most up to date AMAX series for the gauge obtained from SEPA 5 for the purpose of this study; this included data up to 2 November It was noted that the AMAX records received from SEPA were identical to those available on the HiFlows-UK website 6 ; although an additional four years of data were provided within the SEPA dataset. The most up to date SEPA AMAX series was therefore used within the analysis undertaken. However, it was noted by SEPA that there is only confidence in the gauge data up to a flow of approximately QMED; as such the gauge data has only been used in the adjustment of QMED. Additional background information on the gauge at Strathy Bridge was obtained from the National River Flow Archive (NRFA) website 7, and is summarised within Table 2-2. Table 2-2: Gauge Information - River Strathy at Strathy Bridge (96003) Grid Reference NC Station Elevation (maod) 4.5 Mean Flow (m3/s) % Exceedence (m3/s) % Exceedence Average Annual Rainfall (mm) Peak Flow Estimation Peak flow estimations were undertaken for a range of annual probabilities or design events at the flow estimation locations detailed within Section 2.5. Flood estimates for catchments of the size and nature such as these watercourses are frequently undertaken using the Flood Estimation Handbook (FEH). The Flood Estimation Handbook suggests that flow estimates for catchments with a FARL of less than 0.95 should be calculated using the rainfall runoff method. However, in this instance, as gauged data is available on the River Strathy a combination of the statistical and rainfall runoff methods have been utilised. Estimation of QMED An estimation of QMED can be undertaken in one of two ways; (a) using gauged flow data, or (b) using an equation to derive a value from catchment descriptors. A combination of these two methods can also be undertaken, whereby the estimations of QMED from flow data and catchment descriptors at a gauged site are compared to give an adjustment factor which can then be applied to a subject site where the hydrological characteristics are deemed similar. For this purpose the gauged site(s) are termed 'donor sites'. Flow estimations on the River Strathy utilised the Strathy Bridge gauge as a donor for the estimation of QMED, whereas estimations for the sub-catchments derived QMED from catchment descriptors correspondence, Andy Low, SEPA, 18 August s Strathy Wood FRA - Final Report.doc 5

14 The details of the QMED adjustments made for the River Strathy flow estimations can be viewed in Table 2-3. Table 2-3: Parameters of QMED Adjustment for River Strathy Flow Estimations Subject Site River Strathy Bridge River Strathy d/s of The Uair River Strathy u/s of The Uair Donor Site River Strathy Bridge River Strathy Bridge River Strathy Bridge Distance Between Centroids, dij (km) Power Term, a Adjustment Factor QMED from Catchment Descriptors (m3/s) Final Adjusted QMED (m3/s) Flood Growth Curves Due to the low FARL value of the catchment, the flood growth curves have been derived using the rainfall runoff methodology. The growth factors for each catchment are details within Table 2-4. It can be seen that the 1% AP (100 year) growth factors are all within the normal range of 2.1 to 4.0. Table 2-4: Flood Growth Factors Return C1 C2 C3 C4 C5 C6 C7 C8 Period (years) Peak Flows The final peak flows for a range of return periods are displayed in Table 2-5 for the River Strathy and Table 2-6 for the sub-catchments. Table 2-5: Peak Flow Estimates for the River Strathy Return Period (years) Annual Probability [AP] (%) C1 - River Strathy at Strathy Bridge C2 - River Strathy d/s of The Uair C3 - River Strathy u/s of The Uair cc 0.5+cc s Strathy Wood FRA - Final Report.doc 6

15 Table 2-6: Peak Flow Estimates for the Sub-catchments Return Period (years) Annual Probability [AP] (%) C4 - The Uair C5 - Uair Subcatchment A C6 - Uair Subcatchment B C7 - Altan na' Main C8 - Unnamed Upper Catchment cc 0.5+cc The potential effects of climate change were also considered and the design flow for the 0.5% AP (200 year) plus climate change event determined by up scaling by a factor of 20%, as recommended within SEPA s most recent guidance 8. The resulting flow values are also displayed in tables above. 2.6 Hydraulic Modelling Hydraulic modelling was initially undertaken of the existing situation and termed the 'baseline' scenario, and this was then progressed into the modelling of different options for watercourse crossings. The baseline model is detailed below, with the bridge option modelling presented within Section HEC-RAS Models Hydraulic modelling was undertaken within HEC-RAS (Hydraulic Engineering Center-River Analysis System), a one dimensional model software package developed by the US Army Corps of Engineers. Four separate models were constructed to represent the River Strathy, The Uair and two unnamed tributaries; the interaction of the Strathy with the Uair was also investigated. The model locations and geometries are presented within Figure 2-4, with the model extents detailed below: River Strathy: upstream extent NC downstream extent NC The Uair: upstream extent NC downstream extent NC Tributary 1: upstream extent NC downstream extent NC Tributary 2: upstream extent NC downstream extent NC Expansion and contraction coefficients were entered into the model as per the HEC-RAS user manual, and Manning s n values assigned to sections according to observations from the site inspection and the tabulated values in the HEC-RAS manual. The Manning s n values used in the models are typically between and for the channel and to 0.1 for the banks and floodplain areas. The downstream boundary conditions were based on a normal depth relationship for each watercourse, and the effect that water levels in the River Strathy have on levels in The Uair were investigated. 8 SEPA Technical Flood Risk Guidance for Stakeholders, Version 6, August s Strathy Wood FRA - Final Report.doc 7

16 Figure 2-4: Hydraulic Model Geometries Calibration and Sensitivity Analysis Calibration is necessary to develop confidence in the hydraulic model s predictions of flood depths and extents and to test levels of uncertainty and confidence in the parameters used. Calibration is achieved through the use of historic flood data. Ideally, this information is primarily in the form of peak water levels at specific locations, which correspond to peak recorded river flows. Unfortunately no data is available to allow calibration of the models, and sensitivity analysis has therefore been undertaken so as to determine the effect of uncertainty of the different parameters used. The parameters considered are flows (±20%), the downstream boundary condition (±10% of depth) and Manning s n (global ±10%). The analysis was undertaken based on the 0.5% AP (200 year) flow. The results of the sensitivity analysis are displayed within Table 2-7. Table 2-7: Sensitivity Analysis Results Scenario River Strathy The Uair Average Difference (m) Max/ Min Difference (m) Average Difference (m) Max/ Min Difference (m) Flow +20% Flow -20% Manning s +10% Manning s -10% Downstream Boundary +10% Downstream Boundary -10% Downstream Boundary as Level in Strathy n/a n/a s Strathy Wood FRA - Final Report.doc 8

17 Scenario Tributary 1 Tributary 2 Average Difference (m) Max/ Min Difference (m) Average Difference (m) Max/ Min Difference (m) Flow +20% Flow -20% Manning s +10% Manning s -10% Downstream Boundary +10% Downstream Boundary -10% It can be seen that all the models are most sensitive to the flow used. The River Strathy and Uair are relatively sensitive to Manning's 'n', but none of the modelled reaches are particularly sensitive to the downstream boundary due to the steep gradient of the catchments. This is exemplified by Figure 2-5 which shows the 0.5% AP (200 year) modelled levels along The Uair with a normal depth boundary and with the downstream boundary set at the 0.5% AP (200 year) water level in the River Strathy; it can be seen that due to the steep gradient of the channel, changes in the downstream boundary do not propagate far upstream. Figure 2-5: Long Section of The Uair Showing Different Downstream Boundary Conditions Stream_UAIR Reach_200 Uair Legend WS 200yr - ds bdy strathy WS 200yr - final baseline Ground 77 Elevation (m) Main Channel Distance (m) Flood Outlines The 0.5% AP (200 year) plus climate change flood outlines for each of the watercourses modelled are presented in Figure 2-6. It can be seen that all the proposed turbines are located outwith the defined flood zone, and this area should remain undeveloped. 2011s Strathy Wood FRA - Final Report.doc 9

18 Figure 2-6: Modelled 200 Year Plus Climate Change Flood Outlines 2.7 Watercourse Crossings Watercourse crossing optioneering has been undertaken and recommendations provided in line with SEPA s River Crossing Guidance 9. Figure 2-7 shows the existing crossings within the vicinity of the site, along with options for new crossings; further details are provided within Table 2-8. Photographs of the existing crossings on the Uair and Alltan na' Main are shown in Table 2-9. Table 2-8: Existing and Proposed Watercourse Crossings within Site Boundary Crossing A B C & D Details Existing culvert over the Altan na' Main Existing crossing over The Uair - requires upgrading New crossings to be constructed over minor watercourses 1, 2, 3 & 4 Options for new crossing over the River Strathy 9 SEPA (2010) Engineering in the water environment: good practice guide. River crossings, Second Edition, November s Strathy Wood FRA - Final Report.doc 10

19 Figure 2-7: Watercourse Crossings within Site Boundary 2011s Strathy Wood FRA - Final Report.doc 11

20 Table 2-9: Existing Watercourse Crossings within Site Boundary ID Photograph Comments A Iron pipe. c. 0.50m in dia. OS NGR NC B c. 12m in width OS NGR NC E Corrugated Metal Pipe c. 0.50m in dia. OS NGR NC The baseline hydraulic model, as detailed within Section 2.6.1, was used to investigate the effect the proposed changes and new crossings could have on water levels. The modelling considered the following scenarios, with the results for each presented and discussed within the following sections: Upgrade of the existing crossing over The Uair with (a) bridge deck on piers, and (b) bridge deck on a solid abutment across right floodplain. New crossing over the River Strathy at the four potential locations identified (a) with bridge on embankment across floodplains, and (b) with bridge deck raised on piers. New crossings over each of the two unnamed tributaries. 2011s Strathy Wood FRA - Final Report.doc 12

21 A number of assumptions were made during the modelling of the bridges, and these are summarised below: Where the bridge deck has been raised on piers, these have been placed at a spacing of approximately 15 m and set at 2 m in width. Bridge widths were all set at 5 m. Soffit levels were set 600 mm (freeboard) above the 0.5% AP (200 year) plus climate change water level immediately upstream of the structure. Ineffective flow areas were set up and downstream of any abutments, embankments and piers. Freeboard is required to allow for any uncertainty within the calculations and modelling undertaking. In addition, it should help reduce the potential for bridge blockage. This includes the potential for ice blocks within the watercourses to hit the structures; these are anecdotally known to flow down the watercourses during periods of snow melt Crossing Over The Uair There is an existing crossing over The Uair consisting of metal lattice work on a wooden deck. This bridge is located approximately 60 m upstream of the River Strathy Uair confluence. Water levels are anecdotally known to reach the soffit of the bridge during spate conditions, and as such it is likely that there will be a requirement to replace this bridge crossing. The current deck is located at the relief level at which water will flow out of the Uair and across the floodplain. The Uair and floodplain are at a reasonable gradient at this location and therefore any water currently flowing out of bank will simply flow immediately into the River Strathy; there is therefore likely to be limited headloss across the existing structure. Any new structure will need to be situated outwith the main channel, with a deck level set above the 0.5% AP (200 year) with an allowance for climate change and freeboard of 600 mm. The existing bridge is shown within Figure 2-8, with the model cross section presented in Figure 2-9. Figure 2-8: Photograph of the Existing Bridge on The Uair 2011s Strathy Wood FRA - Final Report.doc 13

22 Figure 2-9: Model Cross Section of the Existing Bridge on The Uair 79 Uair RS = BR Legend Elevation (m) WS 200cc WS 50yr WS 2yr Ground Ineff Bank Sta Station (m) Two options were considered for the upgrading of the existing bridge; (a) with the deck raised and connected to high ground and one support pier within the right bank floodplain (Figure 2-10), and (b) with the deck raised, connected to high ground on the left bank and supported on a large abutment on the right bank floodplain (Figure 2-11). The Figures below show the 0.5% AP (200 year) and 50% AP (2 year) modelled flood levels within the proposed bridge structures in place. Figure 2-12 shows a long section of the model reach with the modelled water levels for the 0.5% AP (200 year) plus climate change event during each scenario; these levels are presented in tabular form within Table Figure 2-10: Model Cross Section of Proposed Bridge on The Uair (Option a) 79 Uair RS = BR Legend Elevation (m) WS 200cc WS 50yr WS 2yr Ground Ineff Bank Sta Station (m) Figure 2-11: Model Cross Section of Proposed Bridge on The Uair (Option b) 79 Uair RS = BR Legend Elevation (m) WS 200cc WS 50yr WS 2yr Ground Ineff Bank Sta Station (m) 2011s Strathy Wood FRA - Final Report.doc 14

23 Figure 2-12: Model Long Section on The Uair Showing Different Bridge Options Stream_UAIR Reach_200 Uair Legend WS 200cc - final baseline WS 200cc - br raised piers WS 200cc - br rasied abut Ground Elevation (m) * * * Main Channel Distance (m) Table 2-10: Modelled Water Levels on The Uair for Different Bridge Options Section Baseline (maod).1295* Bridge on Abutment (maod).15625* Difference (m) Bridge on Piers (maod) Difference (m) * * * or * * Notes: * denotes interpolated cross section. Red bold text denotes an increase in water levels. Blue bold text denotes a decrease in water levels. It can be seen that both options reduce the flood water levels in the vicinity of the bridge. This is due to the fact that the current deck is at a relatively low level and therefore acts to significantly raise water levels at the bridge. The proposals for the replacement structure raise the deck above the water levels and therefore increase the flow capacity of the watercourse at the bridge New Crossing Over the River Strathy The current proposal is to provide access over the River Strathy for four turbines to be located on the left bank of the river. During and following the site visit four possible locations for bridge crossings were identified by JBA, and these are presented within Figure s Strathy Wood FRA - Final Report.doc 15

24 Figure 2-13: New Crossing of the Strathy Option Locations Location no. 1 (OS NGR NC ) is located downstream of the Strathy-Uair confluence. This location has been chosen as it would give the greatest ability for the new road to follow the existing contours on the left bank of the river. Location no. 2 (OS NGR NC ) was a site chosen prior to the site visit. This site was chosen due to the SEPA flood map being at its narrowest. Location no. 3 (OS NGR NC ) was suggested by the land owner as this is the location of an existing ford. Location no. 4 (OS NGR NC ) suggested post site visit. Photographs taken at each of these locations are shown within Table s Strathy Wood FRA - Final Report.doc 16

25 Table 2-11: New Crossing of the Strathy Option Locations ID s Strathy Wood FRA - Final Report.doc 17

26 Modelling was undertaken to investigate the effect of constructing a new bridge crossing at each of the four possible locations. Two options were considered at each location; with the bridge raised up on an embankment across the floodplain, and with the bridge deck raised up on piers. Model cross sections and long sections at each location are presented below, along with tables showing the effect the different options have on water levels. Details of the different options are summarised within Table Bridge Location 1 Figure 2-14: Model Cross Section of Proposed Bridge over the River Strathy (Location 1 on Embankment) Strathy RS = BR Legend WS 200cc WS 50yr Elevation (m) WS 2yr Ground Ineff Bank Sta Station (m) Figure 2-15: Model Cross Section of Proposed Bridge over the River Strathy (Location 1 on Piers) Strathy RS = BR Legend WS 200cc WS 50yr Elevation (m) WS 2yr Ground Ineff Bank Sta Station (m) Figure 2-16: Model Long Section on the River Strathy Showing Bridge Options (Location 1) Strathy R_Strathy Reach_100 Legend WS 200cc - baseline WS 200cc - br 1 piers WS 200cc - br 1 embank v2 Ground Elevation (m) Main Channel Distance (m) 2011s Strathy Wood FRA - Final Report.doc 18

27 Table 2-12: Modelled Water Levels on the River Strathy for Different Bridge Options (Location 1) Section Baseline (maod) Bridge on Embankment (maod) Difference (m) Bridge on Piers (maod) Difference (m) Weir New Bridge Notes: * denotes interpolated cross section. Red bold text denotes an increase in water levels. Blue bold text denotes a decrease in water levels. Bridge Location 2 Figure 2-17: Model Cross Section of Proposed Bridge over the River Strathy (Location 2 on Embankment) 88 Strathy RS = BR Legend Elevation (m) WS 200cc WS 50yr WS 2yr Ground Ineff Bank Sta Station (m) Figure 2-18: Model Cross Section of Proposed Bridge over the River Strathy (Location 2 on Piers) 88 Strathy RS = BR Legend Elevation (m) WS 200cc WS 50yr WS 2yr Ground Ineff Bank Sta Station (m) 2011s Strathy Wood FRA - Final Report.doc 19

28 Figure 2-19: Model Long Section on the River Strathy Showing Bridge Options (Location 2) R_Strathy Reach_100 Strathy Legend WS 200cc - baseline WS 200cc - br 2 piers WS 200cc - br 2 embank v2 Ground Elevation (m) Main Channel Distance (m) Table 2-13: Modelled Water Levels on the River Strathy for Different Bridge Options (Location 2) Section Baseline (maod) Bridge on Embankment (maod) Difference (m) Bridge on Piers (maod) Difference (m) Weir * New Bridge Notes: * denotes interpolated cross section. Red bold text denotes an increase in water levels. Blue bold text denotes a decrease in water levels. Bridge Location 3 Figure 2-20: Model Cross Section of Proposed Bridge over the River Strathy (Location 3 on Embankment) 90 Strathy RS = BR Legend Elevation (m) WS 200cc WS 50yr WS 2yr Ground Ineff Bank Sta Station (m) 2011s Strathy Wood FRA - Final Report.doc 20

29 Figure 2-21: Model Cross Section of Proposed Bridge over the River Strathy (Location 3 on Piers) 90 Strathy RS = BR Legend Elevation (m) WS 200cc WS 50yr WS 2yr Ground Ineff Bank Sta Station (m) Figure 2-22: Model Long Section on the River Strathy Showing Bridge Options (Location 3) R_Strathy Reach_100 Strathy Legend WS 200cc - baseline WS 200cc - br 3 piers WS 200cc - br 3 embank v2 Ground Elevation (m) * Main Channel Distance (m) Table 2-14: Modelled Water Levels on the River Strathy for Different Bridge Options (Location 3) Section Baseline (maod) Bridge on Embankment (maod) Difference (m) Bridge on Piers (maod) Difference (m) * New Bridge Weir Notes: * denotes interpolated cross section. Red bold text denotes an increase in water levels. Blue bold text denotes a decrease in water levels. 2011s Strathy Wood FRA - Final Report.doc 21

30 Bridge Location 4 Figure 2-23: Model Cross Section of Proposed Bridge over the River Strathy (Location 4 on Embankment) Strathy RS = BR Legend 92 WS 200cc 90 WS 50yr Elevation (m) WS 2yr Ground Ineff Bank Sta Station (m) Figure 2-24: Model Cross Section of Proposed Bridge over the River Strathy (Location 4 on Piers) Strathy RS = BR Legend 92 WS 200cc 90 WS 50yr Elevation (m) WS 2yr Ground Ineff Bank Sta Station (m) Figure 2-25: Model Long Section on the River Strathy Showing Bridge Options (Location 4) Strathy R_Strathy Reach_100 Legend WS 200cc - baseline WS 200cc - br 4 piers WS 200cc - br 4 embank v2 Ground Elevation (m) Main Channel Distance (m) 2011s Strathy Wood FRA - Final Report.doc 22

31 Table 2-15: Modelled Water Levels on the River Strathy for Different Bridge Options (Location 4) Section Baseline (maod) Bridge on Embankment (maod) Difference (m) Bridge on Piers (maod) Difference (m) New Bridge Weir Notes: * denotes interpolated cross section. Red bold text denotes an increase in water levels. Blue bold text denotes a decrease in water levels. 2011s Strathy Wood FRA - Final Report.doc 23

32 Table 2-16: New Crossing Over the River Strathy Optioneering Location ID Location 1 Location 2 Location 3 Location 4 Bridge Type Bridge Width Across Floodplain (m) Soffit Elevation (maod) Maximum Change in Upstream Water Level (m) Embankment Greatest ability to contour around existing Piers topography. Pros Cons Smallest effect on water levels if constructed on embankment. Long bridge crossing required - floodplain relatively narrow but crossing wide due to freeboard required on deck level. Embankment Shortest crossing option. Erosion to left bank immediately upstream could Piers impact on structure in the future or construction could destabilise this area further. Topography over left bank is steep and could be difficult for access track. Embankment Along line of existing track to ford. Long bridge crossing across wide floodplain. Piers Greatest increase in local water levels Embankment Space to contour round to gain access. Right bank is higher than left. Piers Smallest effect on water levels if constructed on Wide floodplain on left bank. piers. In all locations, the watercourse is modelled as coming out of bank on one side or the other during the 50% AP (2 year) event; there is therefore no preferred location in this respect. 2011s Strathy Wood FRA - Final Report.doc 24

33 It can be seen that each of the proposed options has pros and cons for and against; however, based on the criteria considered within this report, the bridge locations are ranked below in order of preference with regard to flood risk: Option 4 - preferred location. Placing the crossing at this location has the smallest effect on flood water levels (when constructed on piers) and there is scope to contour the access tracks to the bridge with the existing topography. Option 1 - Long bridge crossing but has smallest effect on local water levels if constructed on an embankment. Option 2 - Is the shortest crossing but the area of current erosion upstream would need to be considered carefully. Left bank is also steep and could prove difficult for the construction of access track. Option 3 - Long bridge crossing and has greatest effect on local water levels. However, it should be noted that this analysis does not include all potential parameters, for example, geomorphology and sediment transfer. In general terms, construction on an embankment as opposed to piers would have a greater effect on water levels during flood conditions. Embankments would also have more of an effect on floodplain flow patterns and would increase the time taken for the floodplain to drain after an event; however, this could be taken into consideration during the design phase and it ensured that adequate drainage is provided through the embankments. Construction on piers would have less of an impact on local flow patterns and flood levels, but is likely to be more expensive. Indicative costs for the construction of a crossing at location 4 would be 450,000 with the deck raised up on embankments, and 900,000 with the deck raised on piers New Crossings over Unnamed Tributaries New crossings are proposed over two unnamed tributaries. Both of the tributaries are small watercourses located within narrow, steep valleys. As such, as long as the proposed structures are located above the current flood levels, there would be no effect on water levels within the burns. Modelled cross sections and proposed structure dimensions are presented for each tributary below. Tributary 1 Figure 2-26: Model Cross Section of Proposed Bridge over Tributary Trib_1 RS = BR Legend Elevation (m) WS 200cc WS 50yr WS 2yr Ground Bank Sta Station (m) Deck soffit level = maod Bridge span = 10.9 m 2011s Strathy Wood FRA - Final Report.doc 25

34 Tributary 2 Figure 2-27: Model Cross Section of Proposed Bridge over Tributary 2 Trib_2 RS = BR Legend WS 200cc Elevation (m) WS 50yr WS 2yr Ground Bank Sta Station (m) Deck soffit level = maod Bridge span = 8.3 m Watercourse Crossings Outwith the Site Boundary There are a number of crossings that are located outwith the site boundary, but which convey watercourses beneath the access road to the site; these are likely to require widening. The location of the structures is presented within Figure 2-28, with photographs of each shown in Table Figure 2-28: Watercourse Crossings Outwith the Site Boundary 2011s Strathy Wood FRA - Final Report.doc 26

35 Table 2-17: Watercourse Crossings Outwith the Site Boundary - Photographs Structure Photograph Comments ID 4 Twin rectangular masonry black culvert. c. 1m in height and 0.5m in width. OS NGR NC Concrete pipe culvert. c. 0.75m in dia. OS NGR NC Masonry rectangular block culvert. C. 1.5m in height and 0.5m in width. OS NGR NC s Strathy Wood FRA - Final Report.doc 27

36 7 Twin corrugated iron culverts. Each c. 0.50m dia. OS NGR NC c. 1.5m wide and high OS NGR NC Twin concrete pipes, each c. 0.40m in dia. OS NGR NC c. Corrugated Iron culvert, c. 1m dia. within barrel although inlet collapsed. OS NGR NC s Strathy Wood FRA - Final Report.doc 28

37 11 c. 4 m arch. OS NGR NC Concrete road bridge. Opening c. 0.40m in height, 3 m wide. OS NGR NC CAR Licensing Regulation for the design and construction of the crossing points comes under the Water Environment (Controlled Activities) (Scotland) Regulations 2011 (CAR), with respect to water crossings. The authorisation process operates at three levels to allow for proportionate and risk-based regulation; these are: General Binding Rules Registration Licence - Simple or Complex These levels cover activities with increasing levels of potential impact upon the environment. In the case of the crossing over the River Strathy and The Uair, a simple licence is likely to be required, but the crossings over the two unnamed tributaries are likely to come under the general binding rules as the channel widths are less than 5 m (refer to GBR6). 2.8 Flood Risk Outwith the Site Flood Risk Receptors The site is located in a remote area of Northern Scotland. However, there are several properties downstream of the study area. These are shown graphically in Figure 2-29, with further details provided within Table s Strathy Wood FRA - Final Report.doc 29

38 Figure 2-29: Flood Risk Receptor Locations Table 2-18: Main Flood Risk Receptors Receptor ID Photograph Comments 1 Braerathy Braerathy With site boundary. Set well above floodplain - outside SEPA flood map of the Strathy. OS NGR NC Dallangwell House Downstream of site boundary. Set well above floodplain on paleo terracing - outside SEPA flood map of the Strathy. Access crosses the Strathy. OS NGR NC s Strathy Wood FRA - Final Report.doc 30

39 3 Bowside Cottage Strathy Cottage Downstream of site boundary. Set well above floodplain outside SEPA flood map of the Strathy. OS NGR NC Bowside Lodge Downstream of site boundary. Set well above floodplain outside SEPA flood map of the Strathy. OS NGR NC Strathy Village Hall Downstream of site boundary. Set above floodplain - outside SEPA flood map of the Strathy. OS NGR Wind Turbines It is recommended that no turbines are constructed within the 0.5% AP (200 year) plus climate change flood outline as defined by this study. 2011s Strathy Wood FRA - Final Report.doc 31

40 2.9 Impact of the Development on Fluvial Morphology Designed appropriately the new crossing of the Strathy should not impact of fluvial morphology. Current areas of bank and terracing erosion should be acknowledged and incorporated into the design Changes in Surface Runoff The development of areas of hardstanding at the base of each wind turbine as well as the widening of the existing track and construction of new sections of track will result in localised increases in runoff. In addition, during the construction phase there is also likely to be increases in erosion and sediment transport. Due to the disparate nature of the wind turbines and access tracks, the construction of traditional style SUDs ponds is not appropriate. It is therefore recommended that a system of clean water diversion trenches are constructed upslope of the access tracks and areas of hardstanding, with runoff from the areas of development collected by small drainage channels. Flows from both the clean water diversion channels and development drainage channels should subsequently be directed to a suitable surface water level spreader for overland dispersal. These methods should be implemented both during and post construction. Appropriate pre-discharge treatment of the runoff would be via a gravel filter trench. The treatment volume required for the 50 by 50 m area of hardstanding at the base of each turbine would be 37.5 m Access and Egress The current access track generally lies outwith the 0.5% AP (200 year) plus climate change flood outline as defined within this study. However, the track does cross a number of watercourses between the site and the town of Strathy to the north. The nature of these structures is such that during high flows water is likely to build up on the upstream side and weir over the access track and then flow downslope in to the main valley of the River Strathy. This is exemplified by the crossing over The Uair, where water is shown to overtop the track during the 50% AP (2 year) event and above. Any works required to the existing structures located outwith the site would be assumed to either match the existing capacity of the structures or to exceed them. Due to the nature of the surrounding topography and gradient on the road, flooding from these small watercourses would not be expected to reach extreme depths and should not prevent vehicular access. 2011s Strathy Wood FRA - Final Report.doc 32

41 3 Conclusions and Recommendations E.ON Climate and Renewables Developments Ltd (E.ON) are proposing the development of an onshore wind farm within an area to the south of Strathy in Caithness and Sutherland. The development will require the construction of new river crossings and part of the site lies within SEPA's fluvial Indicative River and Coastal Flood Map (Scotland). As such a more detailed assessment of flood risk, which is specific to the site is required, and this is undertaken herein. The main watercourse passing through the area is the River Strathy, which passes through the west of the site. The Uair converges with the River Strathy towards the downstream extent, and a number of additional small tributaries are also present within the area. Within the development proposal there is a requirement to construct new crossings over the River Strathy as well as over two small tributaries, and to upgrade an existing crossing over The Uair. A baseline hydraulic model was initially developed and was used to investigate the effect the proposed changes and new crossings could have on water levels. The modelling considered the following scenarios: New crossing over the River Strathy at four potential locations with (a) bridge on embankment across floodplains, and (b) bridge deck raised on piers. Upgrade of the existing crossing over The Uair with (a) bridge deck on piers, and (b) bridge deck on a solid abutment across right floodplain. New crossings over two unnamed tributaries. The pros and cons of each potential crossing location over the River Strathy are outlined within the report, with the recommended order of preference summarised below. However, it should be noted that this analysis is only based on the parameters considered within this report, i.e. with regard to flood risk. A plan showing the potential bridge locations can be found within the main body of the report. Option 4 - preferred location. Placing the crossing at this location has the smallest effect on flood water levels (when constructed on piers) and there is scope to contour the access tracks to the bridge with the existing topography. Option 1 - Long bridge crossing but has smallest effect on local water levels if constructed on an embankment. Option 2 - Is the shortest crossing but the area of current erosion upstream would need to be considered carefully. Left bank is also steep and could prove difficult for the construction of access track. Option 3 - Long bridge crossing and has greatest effect on local water levels. Water levels reach the soffit of the existing crossing over The Uair during the 50% AP (2 year) event, with water building up to the upstream of the structure and weiring over the road. Two options are presented for the upgrade of this structure, and both have the effect of reducing the flood water levels in the vicinity of the bridge. The proposals for crossings over the two unnamed tributaries would have no effect on the burns or existing water levels. Access and egress to the site is via an existing track which runs south from the town of Strathy. The track lies outwith SEPA's fluvial Indicative River and Coastal Flood Map (Scotland); however, it does cross a number of watercourses between the site and the town of Strathy to the north. The nature of these structures is such that during high flows water is likely to build up on the upstream side and weir over the access track and then flow downslope in to the main valley of the River Strathy. Any works required to the existing structures located outwith the site would be assumed to either match the existing capacity of the structures or to exceed them. Regulation for the design and construction of the crossing points comes under the Water Environment (Controlled Activities) (Scotland) Regulations 2011 (CAR), with respect to water crossings. The authorisation process operates at three levels to allow for proportionate and risk-based regulation. In the case of the crossing over the River Strathy and The Uair, a 2011s Strathy Wood FRA - Final Report.doc 33

42 simple licence is likely to be required, but the crossings over the two unnamed tributaries are likely to come under the general binding rules. 2011s Strathy Wood FRA - Final Report.doc 34

43 Appendices A Photographs Photograph 1: River Strathy Looking Upstream from Section 1867 Photograph 2: River Strathy Looking Downstream from Section s Strathy Wood FRA - Final Report.doc 35

44 Photograph 3: River Strathy Looking Downstream from Section 1736 Photograph 4: River Strathy Looking Downstream from Section s Strathy Wood FRA - Final Report.doc 36

45 Photograph 5: River Strathy Looking Upstream from Section 1404 Photograph 6: River Strathy Looking Upstream from Section s Strathy Wood FRA - Final Report.doc 37

46 Photograph 7: River Strathy Looking Downstream from Section 1166 Photograph 8: River Strathy Looking Across from Right Bank at Section s Strathy Wood FRA - Final Report.doc 38

47 Photograph 9: River Strathy Looking Downstream from Right Bank at Section 1166 Photograph 10: River Strathy Looking Upstream from Section s Strathy Wood FRA - Final Report.doc 39

48 Photograph 11: River Strathy Looking Downstream from Section 968 Photograph 12: River Strathy Looking Downstream from Left Bank at Section s Strathy Wood FRA - Final Report.doc 40

49 Photograph 13: River Strathy Looking Downstream from Right Bank at Section 968 Photograph 14: River Strathy Looking Across from Right Bank at Section s Strathy Wood FRA - Final Report.doc 41

50 Photograph 15: River Strathy Looking Downstream from Section 778 Photograph 16: River Strathy Looking Across from Left Bank to Uair Confluence 2011s Strathy Wood FRA - Final Report.doc 42

51 Photograph 17: River Strathy Looking Downstream from Section 585 Photograph 18: River Strathy Looking Downstream from Section s Strathy Wood FRA - Final Report.doc 43

52 Photograph 19: River Strathy Looking Downstream from Section 226 Photograph 20: River Strathy Looking Downstream from Section s Strathy Wood FRA - Final Report.doc 44

53 Photograph 21: The Uair Looking Downstream from Section 183 Photograph 22: Upstream Face of Existing Bridge over The Uair at Section s Strathy Wood FRA - Final Report.doc 45

54 Photograph 23: Looking Downstream to the Existing Bridge over The Uair at Section 76 Photograph 24: The Uair Looking Downstream to its Confluence with the River Strathy 2011s Strathy Wood FRA - Final Report.doc 46

55 Photograph 25: Tributary 1 Looking Downstream from Section 251 Photograph 26: Tributary 1 Looking Downstream from Section s Strathy Wood FRA - Final Report.doc 47

56 Photograph 27: Tributary 1 Looking Downstream from Section 135 Photograph 28: Tributary 2 at Section s Strathy Wood FRA - Final Report.doc 48

57 Photograph 29: Tributary 2 Looking Downstream from Section 291 Photograph 30: Tributary 2 Looking Upstream from Section s Strathy Wood FRA - Final Report.doc 49

58 Photograph 31: Tributary 2 Looking Downstream from Section 238 Photograph 32: Tributary 2 Looking Downstream from Section s Strathy Wood FRA - Final Report.doc 50

59 Offices at Atherstone Doncaster Edinburgh Haywards Heath Limerick Newcastle upon Tyne Newport Northallerton Saltaire Skipton Tadcaster Wallingford Warrington Registered Office South Barn Broughton Hall SKIPTON North Yorkshire BD23 3AE t:+44(0) Jeremy Benn Associates Ltd Registered in England Visit our website