Flood Consequence Assessment

Machynlleth General Recreational Land FLOOD CONSEQUENCE ASSESSMENT

8923-FCA-003 DECEMBER 2020 CONFIDENTIAL

Machynlleth General Recreational Land

FLOOD CONSEQUENCE ASSESSMENT

REPORT (RV2) CONFIDENTIAL

PROJECT NO. 70068923 OUR REF. NO. 8923-FCA-003

DATE: DECEMBER 2020

WSP The Mailbox Level 2 100 Wharfside Street Birmingham B1 1RT Phone: +44 1213 524 700 Fax: +44 121 352 4701 WSP.com

QUALITY CONTROL

Issue/revision First issue Revision 1 Revision 2 Revision 3

Remarks Draft for Comment Draft for Comment First Issue

Date December 2020 December 2020 December 2020

Prepared by Jack Grant Jack Grant Jack Grant

Signature

Checked by Alison Caldwell Alison Caldwell Alison Caldwell

Signature

Authorised by Richard Wilks Richard Wilks Richard Wilks

Signature

Project number 70068923 70068923 70068923

Report number Rv0 Rv1 Rv2

File reference 8923-FCA-001 8923-FCA-002 8923-FCA-003

Flood Consequence Assessment WSP Project No.: 70068923 | Our Ref No.: 8923-FCA-003 December 2020 Machynlleth General Recreational Land

CONTENTS

EXECUTIVE SUMMARY 1

1. INTRODUCTION 3

2. SITE SETTING 5

3. POLICY CONTEXT 9

4. ASSESSMENT OF FLOOD RISK 12

5. CONCLUSIONS 17

Flood Consequence Assessment WSP Project No.: 70068923 | Our Ref No.: 8923-FCA-003 December 2020 Machynlleth General Recreational Land

TABLES

Table 1 - Stakeholder Consultation Summary 4 Table 2 - BGS Borehole Summary 8 Table 3 - Flood Risk Overview 12

FIGURES

Figure 1 – Site Location 5 Figure 2 – Baseline Drainage Features 6 Figure 3 – BGS Map Extract (Bedrock Designation) 7 Figure 4 – BGS Map Extract (Superficial Deposits Designation) 7 Figure 5 – NRW Development Advice Map Extract 13 Figure 6 – Natural Resources Wales Flood Risk from Rivers and Sea Map Extract 14 Figure 7 – Surface Water Flood Risk Map 15

APPENDICES

- DRAWINGS - CORRESPONDENCE

WSP Flood Consequence Assessment December 2020 Project No.: 70068923 | Our Ref No.: 8923-FCA-003 Machynlleth General Recreational Land

EXECUTIVE SUMMARY

This Flood Consequence Assessment has been undertaken to accompany the proposed planning application for the proposed site for general recreation purposes in Machynlleth, hereafter referred to as ‘recreational land’. This has been prepared largely in accordance with the guidelines set out in the Technical Advice Note (TAN) 15: Development and Flood Risk published in July 2004 along with other relevant local and national guidance including relevant legislation and policies in Schedule 3 of Flood and Water Management Act (2010) and the Sustainable Drainage (Approval and Adoption) (Wales) Order 2019 (SNSSuDS) and associated regulations.

Item Overview

Site Location The site is located in Machynlleth, Wales. An approximate postcode is: SY20 8DR 7PE and OS Coordinates are: 274339, 300587.

Development Proposals The proposed development consists 1.14ha of recreational land to the west of Machynlleth.

Development Advice Mapping The site is located wholly within Development Advice Mapping (DAM) Zone(s) Zone C2.

Vulnerability Classification(s) Less Vulnerable

Fluvial Flood Risk High

Tidal Flood Risk Very Low

Surface Water Flood Risk Low

Groundwater Flood Risk Low

Sewer Flood Risk Low

Artificial Flood Risk Low

Justification Test Given the sites location within Zone C2 (Development Advice Map), in accordance with current national guidance, the site is required to undertake the Justification Test. Given the proposed use of the recreational land for general recreation purposes, that no changes are proposed to existing ground levels and that the potential consequences of a flooding event for this particular type of development are considered to be negligible, it can be deemed that the development is suitable.

Flood Consequence Assessment WSP Project No.: 70068923 | Our Ref No.: 8923-FCA-003 December 2020 Machynlleth General Recreational Land

1. INTRODUCTION

1.1. BACKGROUND 1.1.1. WSP has been appointed by Powys County Council to prepare a Flood Consequence Assessment (FCA) to support the planning application for recreational land in Machynlleth (approximate Post Code: SY20 8DR). 1.1.2. The objective of the study is to demonstrate that the site may be developed safely, without exposing the development to an unacceptable degree of flood risk or increasing the flood risk to third parties. The primary objectives are to: . Identify the likely potential sources of flooding which may affect the site; and, . Undertake an appraisal of the flood risk posed to the site and potential impact of the development on flood risk elsewhere. 1.2. LIMITATIONS 1.2.1. WSP has prepared this report in accordance with the instructions of their client, Powys County Council, for their sole and specific use. Any person who uses any information contained herein do so at their own risk. © WSP UK Ltd 2020. 1.2.2. The conclusions and recommendations contained herein are limited by the availability of background information and the planned use for the site. 1.2.3. Third party information has been used in the preparation of this report, which WSP UK Ltd, by necessity assumes is correct at the time of writing. Whilst all reasonable checks have been made on data sources and the accuracy of the data, WSP UK Ltd accepts no liability for same. 1.3. CONSTRUCTION (DESIGN AND MANAGEMENT) REGULATIONS 2015 1.3.1. The revised Construction (Design and Management) Regulations 2015 (CDM Regulations) came into force on April 2015 to update certain duties on all parties involved in a construction project, including those promoting the development. One of the designer’s responsibilities under clause 9 (1) is to ensure that the client organisation, in this instance Powys County Council, is made aware of their duties under the CDM Regulations. 1.4. SCOPE OF ASSESSMENT 1.4.1. The assessment has been undertaken in accordance with the overarching national requirements for Flood Consequence Assessment for proposed developments including, but not limited to, the following: . TAN 15: Development and Flood Risk . Development and Flood Risk (C624) . The SuDS Manual (CIRIA C753) . Sustainable Drainage (SuDS) Statutory Guidance 1.4.2. This Flood Consequence Assessment is solely to be used for the proposed recreational land in Machynlleth.

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1.5. CONSULTATION Written Consultation 1.5.1. Ahead of production of this report, consultation was undertaken as summarised in Table 1.

Table 1 - Stakeholder Consultation Summary

Stakeholder Date Received Comments

Powys County Council Lead 04/12/2020 Initial consultation has been undertaken with Powys Local Flood Authority (LLFA) County Council who confirmed there to be no flood records in the proposed recreational land.

Natural Resources Wales 10/12/2020 Initial consultation has been undertaken with NRW who provided the latest Flood Zone data and also confirmed the expected publishing date of the updated TAN15 to be the middle of 2021. 1.5.2. A copy of the consultations is contained in Appendix B.

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2. SITE SETTING

2.1. LOCATION 2.1.1. The site is located to the south-east of Machynlleth with a site location plan shown in Figure 1 and also included in Appendix A. Figure 1 – Site Location

2.2. DEVELOPMENT PROPOSALS 2.2.1. The development proposal is for land used for general recreation purposes over an approximate areal extent of 1.14ha. 2.3. EXISTING TOPOGRAPHY 2.3.1. Available EA 1m DTM LiDAR identifies that the site falls from east to west with levels of approximately 7.18mAOD identified in the south east corner of the site falling to approximately 6.08mAOD on the western boundary of the site. 2.4. EXISTING DRAINAGE NETWORK 2.4.1. Garswin Stream (which is defined as a Main River by Natural Resources Wales) flows east to west, through the northern portion of the site, with School Stream bordering the southern and western boundary of the site with agricultural fields bordered the east of the site. School Stream discharges into the Garswin Stream to the north west of the site before flowing into the Afon Dyfi, a Natural Resources Wales Main River, which flows from east to west, approximately 1.5km south west of the site. These are shown indicatively in Figure 2.

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Figure 2 – Baseline Drainage Features

2.5. GEOLOGICAL AND HYDROGEOLOGICAL CONTEXT Geology 2.5.1. Reference to the British Geological Society (BGS) published mapping identifies the site to be underlain by bedrock of Devil's Bridge Formation (Mudstone and Sandstone) with predominantly overlying superficial Alluvial clay, silt and gravel deposits with a small section to the south east of the site overlain by Alluvial Fan gravel deposits. 2.5.2. An extract of the BGS Bedrock Designation mapping is shown in Figure 3 and BGS Superficial Deposits Mapping is shown in Figure 4.

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Figure 3 – BGS Map Extract (Bedrock Designation)

Figure 4 – BGS Map Extract (Superficial Deposits Designation)

2.5.3. There are a number of boreholes registered approximately 250m east of the site, the deepest of which is 3m. These provide an indication of expected ground conditions on-site in addition to the details provided by the BGS mapping. The following general ground profile is recorded in Table 2.

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Table 2 - BGS Borehole Summary

Description Approximate Depth [mBGL]

Sandy clay topsoil 0.0 – 1.2

Dense, dark brown clayey coarse gravel 1.2 - 2.8 Hydrogeology 2.5.4. According to the Source Protection Zone map provided by Natural Resources Wales, the site does not lie within any Source Protection Zone. 2.5.5. The online DEFRA MAGIC aquifer mapping (Superficial Deposits Designation) indicates that the site is not underlined by an aquifer in its Superficial Deposits. 2.5.6. The online DEFRA MAGIC aquifer mapping (Bedrock Designation) indicates that the site comprises stratum that is considered a ‘Secondary B’ aquifer. That is “aquifers comprise predominantly lower permeability layers which may store and yield limited amounts of groundwater due to localised features such as fissures, thin permeable horizons and weathering”.

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3. POLICY CONTEXT

3.1. TECHNICAL ADVICE NOTE (TAN) 15: DEVELOPMENT AND FLOOD RISK (2004) 3.1.1. Technical Advice Note (TAN) 15 was published in July 2004 and relates to Development and Flood Risk. 3.1.2. The aim of TAN 15 is:  To direct new development away from those areas which are at high risk of flooding, and  Where development has to be considered in high risk areas (Zone C) only those developments which can be justified on the basis of the test outlined in section 6 and section 7 of TAN 15 are located within such areas. 3.1.3. Given the sites location within C2, justification for the development is required as Section 6 of TAN 15 states: “Development, including transport infrastructure, will only be justified if it can be demonstrated that:- i. Its location in zone C is necessary to assist, or be part of, a local authority regeneration initiative or a local authority strategy required to sustain an existing settlement; or, ii Its location in zone C is necessary to contribute to key employment objectives supported by the local authority, and other key partners, to sustain an existing settlement or region; and, iii It concurs with the aims of PPW and meets the definition of previously developed land (PPW fig 2.1); and, iv The potential consequences of a flooding event for the particular type of development have been considered, and in terms of the criteria contained in sections 5 and 7 and appendix 1 found to be acceptable.” 3.1.4. Section 7 of TAN 15 states that if a development in Zones C1 or C2 is defined as low vulnerability and meets the requirements set out in Section 6 (listed above) the justification will be in the knowledge that those developments will flood and will need to be planned accordingly. 3.1.5. Due to the ‘less vulnerable’ use of the recreational land, that no changes are proposed to existing ground levels and that the potential consequences of a flooding event for this particular type of development are considered to be negligible, it can be deemed that the development is suitable. 3.1.6. The draft TAN 15 is currently in production which was last issued in October 2019. This latest Technical Advice Note will replace TAN 15 (2004) and is largely derived from the Flood Risk Assessment Wales (FRAW) map however it also makes consideration for climate change making it suitable for planning purposes. 3.1.7. The proposed changes within the updated TAN 15 that will be relevant to the development of the recreational land are as follows: “Factual updates to terminology and references – e.g. Environment Agency Wales replaced by Natural Resources Wales

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Replacing the Development Advice Map with a new Wales Flood Map, to be maintained by Natural Resources Wales. The Wales Flood Map will show areas at high/medium risk (zone 3), low risk (zone 2) and very low risk (zone 1) as three separate flood zones. Integrating surface water mapping into the new Wales Flood Map, to replace the Zone B advisory classification contained within the Development Advice Map. Summary of proposed policy for the new flood zones

Name of Flood Zone Highly Vulnerable Less Vulnerable Development (inc. housing) Development

Zone 1 Very Low Risk All types of development are acceptable in principle

Zone 2 Low Risk Flood Consequences Assessment required. Any development must meet strict tests. If tests are passed, the development should be designed to be flood-resilient as it cannot be guaranteed that development will not experience flooding. Where there are flood defences it is more likely the tests can be passed

Zone 3 Medium and High Developments should not be Flood Consequences risk proposed Assessment required. Any development must meet Planning authorities should strict tests. If tests are discourage developers from passed, the development preparing speculative Flood should be designed to be Consequences flood-resilient as it should be Assessments. recognised that development is likely to experience flooding. Where there are flood defences it is more likely the tests can be passed.

Changes to the Development Categories, including a new ‘water compatible development’ category. Land-uses such as renewable energy have been added to the guidance, and some development types have changed categories Emphasising the importance of the Development Plan and highlighting the need for comprehensive Strategic Flood Consequences Assessments to inform development strategies, site selection and planning policies. Guidance in relation to the justification and acceptability tests has been updated to make it clear that planning authorities should not consider proposals for highly vulnerable development in high and medium risk areas (zone 3). New advice on making development resilient to flooding and on the consideration when proposing new or improved flood defences.” 3.1.8. Due to the expected changes within the updated TAN 15 that are relevant to the site, it is strongly recommended that the FCA is reassessed when new guidance is published as it will fall into the ‘water compatible development’ category which will likely deem it suitable for development.

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3.2. LOCAL PLANNING POLICY Powys County Council Preliminary Flood Risk Assessment Review of 1st Cycle 2017-2023 3.2.1. The Preliminary Flood Risk Assessment (PFRA) produced by Powys County Council in 2017 does not identify Machynlleth as one of the locations to have experienced significant flooding between 2011- 2017. 3.2.2. The PFRA also does not identify Machynlleth to be a location at considerable future flood risk. 3.2.3. Given this, and the ‘less vulnerable’ nature of the proposed use, it may be considered an acceptable location for the proposed recreational land. Powys County Council Local Flood Risk Management Strategy (LFRMS) (2013-2017) 3.2.4. Powys LFRMS reviews and identifies the key flood risk responsibilities of Powys County Council as well as other key stakeholders such as Severn Trent Water. 3.2.5. The flood risk from groundwater, surface water and flood risk from ordinary watercourses is investigated within the LFRMS. Macynlleth is not identified within the LFRMS as an area of specific risk with the only mention of the area in highlighting Severn Trent Water are responsible for water and sewerage in comparison to Dŵr Cymru Welsh Water serving the majority of the county. Western Wales Flood Risk Management Plan (FRMP) (2013) 3.2.6. The Western Wales FRMP is developed to give an overview of the flood risk in the Western Wales River Basin District and sets out plans to manage and reduce future flood risk in the area. 3.2.7. In the analysis of historic flooding within the catchment, Macynlleth is highlighted several times in the FRMP stating: “In March 1947, abnormal flooding from large winter snowmelt undermined the approach embankment to Railway Bridge near Machynlleth. In February 1952 the railway bridge submerged during flooding at Machynlleth” “In February 2004, several roads and agricultural land flooded in the Wnion, Mawddach and Dyfi catchments. Damage was caused to the A478 across Afon Dyfi in Machynlleth, although no properties were affected.” 3.2.8. Furthermore, it is stated within the FRMP that flood risk is fairly low in the south of Snowdonia (location of Machynlleth) although run-off from the mountains can cause localised flash flooding in the towns and villages in the foothills such as Machynlleth. 3.2.9. It is noted that snowmelt poses a flood risk to Machynlleth, however given the ‘less vulnerable’ use of the recreational land, that no changes are proposed to existing ground levels and that the potential consequences of a flooding event for this particular type of development are considered to be negligible, it can be deemed that the development is suitable.

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4. ASSESSMENT OF FLOOD RISK

4.1. OVERVIEW 4.1.1. Having completed desk-based assessments, the possible flooding mechanisms at the site are summarised below:

Table 3 - Flood Risk Overview

Mechanism Risk Comment

Fluvial High The site is located predominantly in Flood Zone 3 with a small portion in Flood Zone 2 in accordance with Natural Resources Wales mapping.

Tidal Very Low The site is located inland.

Surface Water Low Whilst there are flow paths identified on site associated with the existing ordinary watercourses, space has been made for these within ‘green blue corridors’ in the proposed site masterplan.

Ground Water Low Identified groundwater levels vary across the site, with a peak groundwater level of 1.5mBGL identified.

Sewers Low There are no existing Severn Trent sewers within the site boundary.

Artificial Low There are no reservoirs or canals within the vicinity of the site. Sources 4.2. DEVELOPMENT ADVICE MAP (DAM) The Natural Resources Wales (NRW) Development Advice Map (DAM) shows areas at risk of flooding for the purposes of land-use planning. The DAM should be used alongside Planning Policy Wales and Technical Advice Note (TAN) 15 to guide new development away from areas at risk of flooding wherever possible. An extract of the DAM which identifies the site area is available in Figure 5.

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Figure 5 – NRW Development Advice Map Extract

4.2.1. Figure 5 identifies that the site lies wholly within the identified DAM Zone C2 meaning it is subject to meeting requirements outlined within Section 6 and 7 of TAN 15 as previously highlighted within Section 3. Vulnerability Classification 4.2.2. The development may be classified as “Less Vulnerable” in accordance with Figure 2 of TAN 15. “Less vulnerable development General industrial, employment, commercial and retail development, transport and utilities infrastructure, car parks, mineral extraction sites and associated processing facilities, excluding waste disposal sites.” Justification Test 4.2.3. Given the sites location within DAM Zone C2, in accordance with current national guidance, the site is required to undertake the Justification Test which was previously highlighted in Section 3. 4.2.4. Due to the ‘less vulnerable’ proposed use as recreational land, that no changes are proposed to existing ground levels and that the potential consequences of a flooding event for this particular type of development are considered to be negligible, it can be deemed that the development is suitable in accordance with Tan 15. 4.3. FLUVIAL FLOOD RISK 4.3.1. Reference to the archived Long Term Flood Risk Map in particular in relation to ‘Flood Risk from Rivers and Sea’ as published by Natural Resources Wales in October 2018, it confirms that the site currently lies predominantly within Flood Zone 3 with a small section to the south east falling within Flood Zone 2. The flood zones within the site are assumed to be a result of fluvial flooding from the nearby Afon Dyfi, which runs approximately 550m north west of the site at its closest point.

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4.3.2. An extract of the Natural Resources Wales Flood Risk from Rivers and Sea Long-Term Flood Risk Mapping is reprinted as Figure 6. Figure 6 – Natural Resources Wales Flood Risk from Rivers and Sea Map Extract

4.3.3. It should be noted however that the risk level is under review in this area, with updated mapping scheduled to be published in Spring 2021. 4.3.4. Due to the sites location within Flood Zone 2 and 3, the fluvial flood risk to the proposed development may be considered to be high. Identified Fluvial Flood Risk: High 4.4. TIDAL FLOOD RISK 4.4.1. Due to its inland location, tidal flooding is not considered a risk to this site. Identified Tidal Flood Risk: Low 4.5. SURFACE WATER FLOOD RISK 4.5.1. The ‘Flood Risk Assessment Wales Map,’ in particular relating to the ‘Flood Risk from Surface Water & Small Watercourses’ has been reviewed and identifies the site is located wholly in an area of very low surface water flood risk zone. An extract of this mapping is reprinted as Figure 7.

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Figure 7 – Surface Water Flood Risk Map

4.5.2. The site is identified to be wholly within an area of ‘low risk’ from surface water & small watercourses. Identified Surface Water Flood Risk: Low 4.6. GROUNDWATER FLOOD RISK 4.6.1. As previously mentioned in Section 3, Machynlleth is not highlighted as an area of flood risk within the Powys County Council PFRA. This is reiterated within the Powys County Council Local Flood Risk Management Strategy (2013-2017) which states “Powys PFRA did not identify any areas susceptible to groundwater flooding across the county. The risk of groundwater flooding is considered to be low, this being confirmed generally in all eight of the ten CFMP’s (EAW, 2009) covering Powys, which state that groundwater flooding is not considered to be a significant issue within the County.” 4.6.2. Given the information noted above the flood risk from groundwater is considered low. Identified Groundwater Flood Risk: Low 4.7. SEWER FLOOD RISK 4.7.1. Sewer flooding occurs as a result of a number of influencing factors. It's most likely to occur during storms, when large volumes of rainwater enter the sewers. However, it can also occur when pipes become blocked or damaged. 4.7.2. Given that the proposed recreational land is not located in close proximity to any existing public sewers, and that the recreational land does not require a connection to a sewer, it may be considered that sewer flood risk is low. Identified Sewer Flood Risk: Low

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4.8. ARTIFICIAL SOURCE FLOOD RISK Reservoirs 4.8.1. Reference to the publicly available Flood Risk Assessment Wales Map in particular in relation to ‘Flood Risk from Reservoirs as published by Natural Resources Wales identifies that the site lies wholly outside the maximum flood risk extents from reservoirs. 4.8.2. As such, the flood risk from reservoirs is considered low. Identified Flood Risk from Reservoirs: Low Canals 4.8.3. There are no canals within the vicinity of the site and as such, risk of flooding from canals is considered low. Identified Flood Risk from Canals: Low 4.9. DEVELOPMENT EXCEEDANCE FLOWS 4.9.1. Given the nature of the recreational land, and that the proposals aim to retain existing ground levels, existing exceedance flow routes within the development will be retained. Given this, the risk of flooding from exceedance flows may be considered to be low. Identified Flood Risk from Exceedance Flows: Low

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5. CONCLUSIONS

5.1.1. WSP has been appointed by Powys County Council to prepare a Flood Consequence Assessment (FCA) to support the planning application for recreational land in Machynlleth (approximate Post Code: SY20 8DR). 5.1.2. The proposed development comprises recreational land, with negligible proposed changes to existing ground levels. 5.1.3. The site is identified to lie within Zone C2 within the Development Advice Map and at high risk of flooding from rivers, in accordance with the Flood Risk Assessment Wales Map. Further to this, it is identified to be at very low risk of flooding from surface water & small watercourses. 5.1.4. Given the ‘less vulnerable’ nature of the proposed recreational land, that no changes are proposed to existing ground levels and that the potential consequences of a flooding event for this particular type of development are considered to be negligible, this FCA aims to demonstrate that the proposed development is considered appropriate, largely in accordance with TAN15.

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DRAWINGS

Hardworks:

New sliding timber entrance gate to southern boundary by existing public footpath. Reduced run off width / length at corner of pitch unless existing Softworks: fenceline can be moved back. Rugby guidance states that run off can be reduced to less than 5m if Hard wearing amenity grass to playing risk assessment is carried out and field pitch. Grass pitch to be proprietary reduced distance deemed winter sports pitch seed mix or turf with appropriate high amenity ryegrass content.

NOTES:

· All existing levels to be retained. · All drainage improvement proposals to playing field to civil engineer's details and specification

Existing maintenance access to be retained and used only for emergency/maintenance.

Refer to drawing 493-CTF-XX-ZZ-DR-L-0023

Proposed Pitch

Ysgol Bro Hyddgen, Machynlleth

Refer to drawing 493-CTF-XX-ZZ-DR-L-0022 Levels to be kept as existing. Improvement to existing ground to facilitate better drainage of the fields. To Engineer's details and specification. New lockable gate to existing post and wire fence for entrance to fields from public footpath

Existing brook Hedge to be cut back here to maintain 5m overrun from Rugby Pitch Existing post and wire fence

Do not scale drawings. All dimensions to be checked on site. Site Boundary Revision Tracker Status Date 24.11.2020 Errors to be reported immediately to landscape architect. P01 - Issued for PAC S2 16.12.2020 Scale 1:500/A1 To be read in conjunction with all relevant architects, Services and engineers drawings. London Drawn AA/WD 3rd Floor, 14 Bowden Street, Kennington, London SE11 4DS Location Machynlleth, Wales +44(0)20 3727 6780 Client HOWPS Status Bristol 1.14 Temple Studios, S2 Temple Gate, BS1 6QA Land North West of Ysgol Bro Hyddgen +44(0)20 3727 6788 Proposed GA Plan (Block Plan) Revision P01 © Churchman Thornhill Finch [email protected] 493-CTF-XX-ZZ-DR-L-0021 6.533 m 6.566 m 6.675 m 6.644 m LEGEND: 6.514 m Hardworks: 6.556 m 6.702 m New sliding timber entrance gate to 6.533 m 6.500 m southern boundary by existing public 6.470 m footpath. 6.471 m Reduced run off width / length at 6.480 m corner of pitch unless existing Softworks: 6.447 m fenceline can be moved back. Rugby guidance states that run off 6.375 m 6.4216.491 m m can be reduced to less than 5m if Hard wearing amenity grass to playing 6.532 m risk assessment is carried out and field pitch. Grass pitch to be proprietary 6.459 m reduced distance deemed winter sports pitch seed mix or turf with appropriate high amenity ryegrass content. 6.514 m 6.316 m 6.3796.418 m6.418 m m 6.511 m 6.5056.378 m m 6.4756.498 mm 6.396 m NOTES: 6.392 m 6.421 m · All existing levels to be retained. 6.417 m 6.416 m · All drainage improvement proposals to playing field 6.391 m 6.396 m to civil engineer's details and specification 6.338 m 6.361 m 6.3516.438 m m 7.115 m 6.306 m 6.214 m 6.834 m 6.432 m 7.077 m 6.686 m 6.413 m 7.028 m 6.2336.240 mm 7.1727.165 m 7.373 m 6.295 m 7.114 m 7.327 m 6.843 m 7.444 m 7.024 m 6.740 m 7.157 m 7.392 m 7.660 m 7.103 m 6.672 m 6.635 m 6.639 m 7.098 m 7.060 m 6.917 m 2520 3264 7.143 m 7.106 m 6.882 m 6.932 m 6.925 m 6.844 m 6.858 m 7.237 m 6.581 m 6.437 m 6.854 m 6.649 m 7.128 m 6.851 m 6.749 m 7.129 m 6.835 m 6.958 m 5024 6.460 m 6.995 m 6.983 m

6.654 m 6.692 m 6.834 m 6.598 m 58951 6.779 m 6.757 m 6.700 m 6.912 m 6.826 m 6.609 m

6.932 m 6.718 m 6.714 m 6.825 m 6.785 m 6.533 m 7.090 m 6.730 m 6.752 m 6.783 m 6.846 m 6.794 m 6.744 m 6.688 m

6.881 m 6.6686.569 mm 6.646 m 6.644 m 6.831 m 6.713 m 6.956 m 6.823 m 6.750 m 6.8156.821 m 6.733 m 6.674 m 6.777 m 6.807 m 6.840 m 6.699 m 6.661 m 6.642 m 6.712 m 6.831 m 6.752 m 6.877 m 6.655 m 6.557 m 6.7026.633 m 6.790 m 6.496 m 6.573 m 6.684 m 6000 6.613 m 6.523 m 6.709 m 6.760 m 6.714 m 6.514 m 6.546 m 5210 6.743 m 6.417 m 6.569 m 6.209 m 6.604 m 6.666 m 6.425 m 6.732 m 6.387 m 6.752 m

6.609 m 6.693 m 5000 4545 6.552 m 6.415 m 6.5656.560 m 6.624 m 6.704 m 6.794 m 6.670 m 6.582 m 6.820 m 6.6096.607 m m 6.649 m 68000

6.799 m

6.556 m 6.790 m 6.331 m 6.526 m 6.472 m 6.587 m 6.495 m 6.647 m Existing maintenance 6.522 m 6.676 m access to be retained 6.675 m 6.523 m 6.698 m and used only for emergency/maintenance. 6.669 m 6.505 m 6.759 m 6.535 m 6.648 m 6.435 m 6.523 m 6.596 m 6.637 m

6.291 m 6.629 m 6.555 m 6.646 m Refer to to drawing drawing 493-CTF-XX-ZZ-DR-L-0023 493-CTF-XX-ZZ-DR-L-0023 6.513 m 50982 6.523 m 6.986 m 6.481 m

6.512 m 6.503 m 6.870 m 6.571 m 6.299 m 6.601 m 6.850 m 6.447 m

5000 6.464 m 6.557 m 6.669 m 6.227 m 6.730 m Proposed Pitch 6.418 m 6.494 m 6.405 m 6.442 m 6.569 m 6.463 m 6.626 m 6.990 m 6.376 m 6.932 m 6.506 m 6.672 m 6.533 m 6.333 m 7.341 m 6.828 m 6.328 m 94000 6.564 m

6.152 m 6.1025.709 m m 6.611 m 6.679 m 7.755 m 6.236 m 7.292 m 6.771 m 6.578 m 7.069 m

6.332 m 4184 6.849 m 7.348 m

6.419 m 6.548 m 6.670 m 6.745 m 7.758 m

6.443 m 6.556 m 6.836 m

6.512 m 6.503 m 6.870 m New sliding timber entrance gate to 6.571 m 6.299 m 6.601 m 6.850 m southern boundary by existing public 6.447 m footpath. 5000 6.464 m 6.557 m 6.669 m 7.0847.227 m m 6.227 m 6.730 m Softworks: 6.418 m Proposed Pitch 7.651 m 6.494 m 6.405 m Hard wearing amenity grass to playing 6.442 m field pitch. Grass pitch to be proprietary 6.569 m winter sports pitch seed mix or turf with 6.463 m 6.626 m 6.990 m 6.376 m high amenity ryegrass content. 6.932 m 6.506 m 6.672 m 6.533 m 6.333 m 7.341 m 6.828 m NOTES: 6.328 m 94000 6.564 m · All existing levels to be retained. 6.152 m · All drainage improvement proposals to playing field 6.1025.709 m m 6.611 m to civil engineer's details and specification 6.679 m 7.755 m 6.236 m 7.292 m 6.771 m 6.578 m 7.069 m

6.332 m 4184 6.849 m 7.348 m

6.419 m 6.548 m 6.670 m 7.758 m 6.745 m Refer to drawing 493-CTF-XX-ZZ-DR-L-0022

6.443 m 6.556 m 6.836 m 7.2087.271 m m Levels to be kept as existing. Improvement to existing 6.957 m ground to facilitate better drainage of the fields. To 6.533 m 6.559 m Engineer's details and 6.684 m specification. 6.798 m 7.367 m

3055 6.556 m 6.921 m 6.416 m 7.259 m 7.427 m 6.235 m 6.781 m New lockable gate to 6.522 m 6.659 m existing post and wire fence 6.947 m for entrance to fields from 7.216 m 7.391 m public footpath 6.617 m 6.420 m

6.955 m 7.361 m 6.562 m 6.810 m 6000 7.186 m

6.089 m 5000

6.699 m 7.105 m 7.246 m 6.531 m

6.619 m 6.968 m 7.155 m

6.460 m

6.871 m Existing brook 7.089 m 6.680 m Hedge to be cut back here to 6.849 m 6.981 m maintain 5m overrun from Rugby Pitch 6.468 m 6.865 m 6.704 m

Existing post and 6.7436.746 m wire fence 6.575 m

CORRESPONDENCE

Grant, Jack

From: Graham Astley Sent: 04 December 2020 18:13 To: Grant, Jack Cc: Land Drainage Subject: FW: Machynlleth Playing Fields

Follow Up Flag: Follow up Flag Status: Flagged

Good evening Jack,

Your email has been forwarded to me by other colleagues.

With regard to your enquiry, the LLFA holds no flood records relating the area of land you are interested in. This does not mean the land has not flooded but the fact the LLFA has no historical information to say it has. Probably your best bet is to seek advice from local residents in this instance.

The only recorded flooding (and most recent) the LLFA holds relates to Heol Pentrerhedyn (A487T) and property near to Y Plas. In a report prepared by the then Montgomeryshire District Council, flooding occurred in December 1986, when the highway “was flooded to a depth of approximately 300mm and seven houses had water in on the ground floor”. The report indicates floods similar to that in 1986 occurred in 1964, 1954 and 1938.

The source of this flood water stemmed from minor watercourses (located to the south of the A487T and Y Plas grounds) being exceeded. The LLFA is aware that the former District Authority carried out a flood alleviation scheme in earlier 1990, with the diversion of these minor watercourses and introduction of a larger culvert system to convey all flood flows. As far as the LLFA is aware, no significant flood incidents have occurred since the introduction of the flood alleviation scheme.

Hope this is of assistance but should you have any further queries then please let me know. For future reference, our generic email address is [email protected]

Regards

Graham

Graham Astley Senior Land Drainage Officer Powys County Council

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From: Stuart Eckley Sent: 04 December 2020 14:14 To: Graham Astley Subject: Fwd: Machynlleth Playing Fields

1 Afternoon Graham, Is this an enquiry you can assist with please?

Stu

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From: Grant, Jack Sent: Friday, December 4, 2020 2:09:55 PM To: Emergency Planning Subject: FW: Machynlleth Playing Fields

Hello

WSP have been appointed to undertake a Flood Consequence Assessment (FCA) for proposed playing fields in Machynlleth (OS grid reference: 274300, 300650).

A site location plan is below:

WSP would like to request any records of flooding for the site or local area that you hold.

Many thanks

Jack Grant BSc (Hons) MCIWEM Engineer – Development Infrastructure

T +44 (0) 121 352 4777

WSP, The Mailbox Level 2 100 Wharfside Street Birmingham B1 1RT wsp.com 2

Confidential This message, including any document or file attached, is intended only for the addressee and may contain privileged and/or confidential information. Any other person is strictly prohibited from reading, using, disclosing or copying this message. If you have received this message in error, please notify the sender and delete the message. Thank you.

WSP UK Limited, a limited company registered in England & Wales with registered number 01383511. Registered office: WSP House, 70 Chancery Lane, London, WC2A 1AF.

From: Luke Woosnam On Behalf Of Planning Services Sent: 04 December 2020 14:06 To: Grant, Jack Subject: FW: Machynlleth Playing Fields

Hi Jack, Possibly emergency planning otherwise NRW.

Emergency Planning

Kind Regards

Planning Services

Development Control - Rheoli Datblygu Powys County Council - Cyngor Sir Powys

County Hall, Spa Road East, Llandrindod Wells, LD1 5LG  [email protected] ✆ 01597827161 / 01597827169 https://en.powys.gov.uk/planning/building_control

Croesewir gohebiaeth yn y Gymraeg a’r Saesneg/Correspondence welcomed in Welsh and English

Diogelu Data a Chyfrinachedd: Er mwyn cyflawni ceisiadau, cwynion ac apeliadau'r Gwasanaeth Cynllunio mae angen i’r cyngor brosesu data personol yn unol â’r ddeddfwriaeth gynllunio berthnasol, sydd i’w weld ar wefan gynllunio Llywodraeth Cymru (https://gov.wales/topics/planning/?skip=1&lang=cy). Bydd y Gwasanaeth Cynllunio’n cadw Gwybodaeth yn unol â’r ddeddfwriaeth ac amserlen cadw’r Cyngor. Os oes gennych bryderon am sut rydym yn defnyddio’ch data personol cysylltwch â’r Swyddog Diogelu Data trwy e-bost [email protected] neu drwy ffonio 01597 826400. Cofiwch y gallwch gael hyd i fwy o wybodaeth am Ddiogelu Data a Chyfrinachedd trwy fynd i: https://cy.powys.gov.uk/article/653/Defnyddio-Cwcis.

Data Protection and Privacy: In order to deliver the Planning Service (applications, complaints and appeals etc.) it is necessary for the council to process personal data, in accordance with relevant planning legislation, as listed on the Welsh Governments planning website (https://gov.wales/topics/planning/?lang=en). Information held by the Planning Service will be retained in accordance with the legislation and the Councils retention schedule. If you have any concerns regarding the use of your personal data please contact the Data Protection Officer by email at [email protected] or by phone at 01597 826400. Please note that further information on the Data Protection and Privacy can be found at the following address: https://en.powys.gov.uk/privacy.

3 From: Grant, Jack Sent: 04 December 2020 12:02 To: Engineering Design ; Planning Services Subject: Machynlleth Playing Fields

Hello

WSP have been appointed to undertake a Flood Consequence Assessment (FCA) for proposed playing fields in Machynlleth (OS grid reference: 274300, 300650).

A site location plan is below:

WSP would like to request any records of flooding for the site or local area that you hold.

I was unable to find a specific LLFA email so I am hoping this email has been sent to the correct email. If not could you please forward it to the relevant department?

Many thanks

Jack Grant BSc (Hons) MCIWEM Engineer – Development Infrastructure

T +44 (0) 121 352 4777

WSP, The Mailbox Level 2 100 Wharfside Street Birmingham B1 1RT wsp.com

WSP UK Limited, a limited company registered in England & Wales with registered number 01383511. Registered office: WSP House, 70 Chancery Lane, London, WC2A 1AF.

NOTICE: This communication and any attachments ("this message") may contain information which is privileged, confidential, proprietary or otherwise subject to restricted disclosure under applicable law. This message is for the sole use of the intended recipient(s). Any unauthorized use, disclosure, viewing, copying, alteration, dissemination or distribution of, or reliance on, this message is strictly prohibited. If you have received this message in error, or you are not an authorized or intended recipient, please notify the sender immediately by replying to this message, delete this message and all copies from your e- mail system and destroy any printed copies.

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Mae'r e bost hwn ac unrhyw atodiad iddo yn gyfrinachol ac fe'i bwriedir ar gyfer y sawl a enwir arno yn unig. Gall gynnwys gwybodaeth freintiedig. Os yw wedi eich cyrraedd trwy gamgymeriad ni ellwch ei gopio, ei ddosbarthu na'i ddangos i unrhyw un arall a dylech gysylltu gyda Cyngor Sir Powys ar unwaith. Mae unrhyw gynnwys nad yw'n ymwneud gyda busnes swyddogol Cyngor Sir Powys yn bersonol i'r awdur ac nid yw'n awdurdodedig gan y Cyngor.

This e mail and any attachments are confidential and intended for the named recipient only. The content may contain privileged information. If it has reached you by mistake, you should not copy, distribute or show the content to anyone but should contact Powys County Council at once. Any content that is not pertinent to Powys County Council business is personal to the author, and is not necessarily the view of the Council.

5 Grant, Jack

From: Open Data Sent: 10 December 2020 11:29 To: Grant, Jack Subject: RE: Archived Flood Zones 2 and 3 from January 2020

Follow Up Flag: Follow up Flag Status: Flagged

Good morning Jack,

I’ve checked with our Development Planning team. They have advised that the revised TAN15 is due to be published the middle of next year, but the time could possibly be later than that due to the current situation with Covid19.

We advise that you contact Welsh Government about this for further information as the TAN is their document https://gov.wales/contact-us

Kind regards, Rachel

Gweinyddwr Cyfrif Data Agored / Open Data Account Administrator Gwasanaethau Data / Data Services Cyfoeth Naturiol Cymru / Natural Resources Wales [email protected]

Yn falch o arwain y ffordd at ddyfodol gwell i Gymru trwy reoli’r amgylchedd ac adnoddau naturiol yn gynaliadwy. Proud to be leading the way to a better future for Wales by managing the environment and natural resources sustainably. cyfoethnaturiol.cymru / naturalresources.wales Twitter Facebook LinkedIn Instagram

Croesewir gohebiaeth yn Gymraeg a byddwn yn ymateb yn Gymraeg, heb i hynny arwain at oedi. Correspondence in Welsh is welcomed, and we will respond in Welsh without it leading to a delay.

From: Grant, Jack Sent: 08 December 2020 14:26 To: Open Data Subject: RE: Archived Flood Zones 2 and 3 from January 2020

Hi Rachel

Thank you for this!

Could you please confirm when the draft TAN 15 is expected to be issued?

Many thanks

Jack Grant BSc (Hons) MCIWEM Engineer – Development Infrastructure

T +44 (0) 121 352 4777

WSP, The Mailbox Level 2 100 Wharfside Street Birmingham B1 1RT wsp.com

WSP UK Limited, a limited company registered in England & Wales with registered number 01383511. Registered office: WSP House, 70 Chancery Lane, London, WC2A 1AF.

From: Open Data Sent: 08 December 2020 14:25 To: Grant, Jack Subject: RE: Archived Flood Zones 2 and 3 from January 2020

Good afternoon Jack,

Thank you for your reply. The data can be downloaded from these links:

Flood Zone 3 https://naturalresourceswales.sharefile.eu/d-sacc7cda51b042449 Flood Zone 2 https://naturalresourceswales.sharefile.eu/d-sa6795472641489d8

You can re-use this data under the terms of the Open Government Licence providing it is done so, acknowledging both the source and copyright of the owners. It is your responsibility to ensure the data is fit for the intended purpose and take into account that these datasets have been discontinued and are therefore static and won’t be updated.

The attribution/copyright statement is: “© CNC/NRW and Centre for Ecology and Hydrology © NERC (CEH). Some features of this information are based on digital spatial data licensed from the Centre for Ecology and Hydrology © NERC (CEH). Defra, Met Office and DARD Rivers Agency © Crown copyright. © Cranfield University. © James Hutton Institute. Contains OS data © Crown copyright and database right 2015. Land and Property Services © Crown copyright and database right.”

We provided this data to a colleague of yours at WSP in November. However I note they are based in Liverpool and you are based in Birmingham. Is there any way you are able to store this data centrally so that others from within your company can access it?

Kind regards, Rachel

Gweinyddwr Cyfrif Data Agored / Open Data Account Administrator Gwasanaethau Data / Data Services Cyfoeth Naturiol Cymru / Natural Resources Wales [email protected]

Croesewir gohebiaeth yn Gymraeg a byddwn yn ymateb yn Gymraeg, heb i hynny arwain at oedi. Correspondence in Welsh is welcomed, and we will respond in Welsh without it leading to a delay.

From: Grant, Jack Sent: 07 December 2020 14:12 To: Open Data Subject: RE: Archived Flood Zones 2 and 3 from January 2020

Hi Rachel

If you could please send through the Flood Zone 2 and 3 as we will use that data as the latest available data in our current investigation. This will be subject to change once the new data becomes available.

Many thanks

Jack Grant BSc (Hons) MCIWEM Engineer – Development Infrastructure

T +44 (0) 121 352 4777

WSP, The Mailbox Level 2 100 Wharfside Street Birmingham B1 1RT wsp.com

WSP UK Limited, a limited company registered in England & Wales with registered number 01383511. Registered office: WSP House, 70 Chancery Lane, London, WC2A 1AF. 3

From: Open Data Sent: 07 December 2020 14:07 To: Grant, Jack Subject: RE: Archived Flood Zones 2 and 3 from January 2020

Dear Jack,

Thank you for your e-mail.

The new Flood Risk Assessment Wales map has recently been published. Consequently the Flood Map: Flood Zone 2 and Flood Zone 3 data have been removed from Lle to avoid confusion and to consolidate mapping information in advance of publication of the new Flood Map for Planning scheduled for Spring 2021. Further information is available on the Lle news and announcements at this link http://lle.gov.wales/News?lang=en#20

Taking this in to account, please can you advise if you still require the Flood Zone 2 and 3 data? We are able to provide this but please bear in mind these datasets have been discontinued and are therefore static and won’t be updated.

Kind regards, Rachel

Gweinyddwr Cyfrif Data Agored / Open Data Account Administrator Gwasanaethau Data / Data Services Cyfoeth Naturiol Cymru / Natural Resources Wales [email protected]

Croesewir gohebiaeth yn Gymraeg a byddwn yn ymateb yn Gymraeg, heb i hynny arwain at oedi. Correspondence in Welsh is welcomed, and we will respond in Welsh without it leading to a delay.

From: Grant, Jack Sent: 02 December 2020 16:02 To: Open Data Subject: Archived Flood Zones 2 and 3 from January 2020

Hello

Would it be possible to provide WSP with a link to the archived flood zones 2 and 3 from January 2020 for the Machynlleth area please?

Many thanks

Jack Grant BSc (Hons) MCIWEM Engineer – Development Infrastructure

T +44 (0) 121 352 4777

WSP, The Mailbox Level 2 100 Wharfside Street Birmingham B1 1RT wsp.com

WSP UK Limited, a limited company registered in England & Wales with registered number 01383511. Registered office: WSP House, 70 Chancery Lane, London, WC2A 1AF.

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5 From: Pilcher, Ian [mailto:[email protected]] Sent: 07 December 2020 15:33 To: Wilks, Richard ; lee.fordham ; Richard Bowen Cc: Alex Achniotis ; Liam Griffiths ; george.mikurcik ; Evans, Stuart ; Nia Jardine ; Katie de Silva ; Will Day ; Caldwell, Alison Subject: RE: 20.231 - Land north of Ysgol Bro Hyddgen

Hi Richard.

Nominated Flood Management Coordinator will be the Head Teacher or his appointed deputy / representative. Contact Details - Mr Daffyd Jones. Main School Number - 01654 704200.

The school site will constitute the safe evacuation route / refuge area.

Ian Pilcher. Senior Project Manager. Heart Of Wales Property Services Ltd. / Gwasanaethau Eiddo Calon Cymru Cyf Mobile: 07773 078289

Heart Of Wales Property Services Ltd. Unit 31 Ddole Road Industrial Estate, Llandrindod Wells, Powys. LD1 6DP

The Mailbox Level 2 100 Wharfside Street Birmingham B1 1RT wsp.com