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APPENDIX 8.1 – FLOOD
CONSEQUENCES ASSESSMENT (FCA)
LIGHTSOURCE
CWRT HENLLYS FARM SOLAR DEVELOPMENT
Flood Consequences Assessment
Hyder Consulting (UK) Limited
HCL House
St Mellons Business Park
St Mellons
Fortran Road
Cardiff
CF3 0EY
www.hyderconsulting.com
LIGHTSOURCE
CWRT HENLLYS FARM SOLAR DEVELOPMENT
Flood Consequences Assessment
Author E Coward
Checker L Driscoll
Approver L Walker
Report No 5001-UA008142-UU41-01
Date 22 July 2015
This report has been prepared for Lightsource in
accordance with the terms and conditions of Hyder’s
appointment dated 08 June 2015. Hyder Consulting (UK)
Limited (2212959) cannot accept any responsibility for any
use of or reliance on the contents of this report by any third
party.
Cwrt Henllys Farm Solar Development - Flood Consequences Assessment
Hyder Consulting (UK) Limited-2212959 Page i
CONTENTS
1 Introduction ........................................................................................... 1
2 Site Description .................................................................................... 2
2.1 Location ................................................................................................ 2
2.2 Catchment Description ......................................................................... 3
2.3 Development Proposals........................................................................ 4
3 Assessment Methodology .................................................................... 5
3.1 Data Collection ..................................................................................... 5
3.2 Surface Water Runoff Calculations ....................................................... 5
3.3 Flood Risk Assessment ........................................................................ 6
4 Technical Advice Note (TAN) 15 .......................................................... 7
4.1 General ................................................................................................. 7
4.2 DAM Zone Categorisation .................................................................... 7
4.3 Sequential Test ..................................................................................... 8
4.4 Need for a FCA ..................................................................................... 8
5 Potential Sources of Flood Risk ........................................................... 9
5.1 Historic Flooding ................................................................................... 9
5.2 Fluvial Flood Risk ................................................................................. 9
5.3 Coastal Flood Risk ............................................................................. 10
5.4 Surface Water ..................................................................................... 10
5.5 Groundwater ....................................................................................... 11
5.6 Artificial Sources ................................................................................. 12
6 Surface Water Drainage Assessment ................................................ 13
6.1 Planning Policy Requirements ............................................................ 13
6.2 Existing Drainage ............................................................................... 13
6.3 Effects of the Proposed Development ................................................ 13
6.4 Drainage Strategy ............................................................................... 14
7 Summary ............................................................................................ 16
Appendices
Appendix A
Site Location Plan and Proposed Development Layout
Appendix B
Site Topography
Appendix C
Rainfall Runoff Volume Calculations
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1 Introduction
Hyder Consulting (UK) Limited has been commissioned by Lightsource Renewable Energy
Limited to undertake a Flood Consequences Assessment (FCA) to support a planning application
for the proposed development of a Solar Farm on land at Cwrt Henllys to the south west of
Cwmbran, in Torfaen, South Wales.
The proposed development would have a generating capacity of up to 5 megawatts (MW). It
would occupy an area of land equating to approximately 14 hectares.
The Welsh Government’s (WG) Development Advice Maps (DAMs), which accompany latest
planning policy on development and flood risk: Technical Advice Note 15 (TAN 15), highlight that
the proposed development site lies entirely within Zone A, where there is considered to be little
or no risk of fluvial or tidal/coastal flooding. However, these maps do not consider flood risk from
ordinary watercourses, of which there are two located in the vicinity of the site, or other sources
of flooding.
A FCA has therefore been prepared that presents the approach taken to evaluate all forms of
flood risk to the proposed development and considers the potential impact on flood risk to other
sites within the catchment.
2 Site Description
2.1 Location
The proposed development site comprises five individual fields, located to the west of Cwrt
Henllys Farm at National Grid Reference 325330, 191976 (see Figure 2-1). A detailed location
plan is provided in Appendix A.
Figure 2-1 Site location plan (indicative site location shown in red)
Contains Ordnance Survey data © Crown copyright and database right 2015
Access to the proposed development site is from an existing track at Cwrt Henllys Farm, off the
minor road leading to Bettws and the A4051. The proposed development site is currently located
on land which is laid to grass with livestock grazing (see Figure 2-2).
Proposed development
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Figure 2-2 Existing land use (proposed development area outlined in red)
Microsoft Corporation © 2015
Site specific topographical survey data illustrates that the ground elevation varies between
approximately 200m and 145m Above Ordnance Datum (AOD), with the general gradient of the
land steeply sloping downhill from the north-west boundary to the south east (See Appendix B for
topographical survey).
2.2 Catchment Description
The proposed development site is located in the headwaters of the catchment of the Pantyreos
Brook. The Pantyreos Brook is known as the Bettws Brook in its lower reaches and confluences
with the Malpas Brook, a tributary of the River Usk, on the outskirts of Newport.
The watercourse rises from several spring sources at the foot of Mynydd Henllys and flows in a
south easterly direction, adjacent to the south western boundary of proposed development. This
watercourse provides a source of inflow to the Pantyreos reservoir approximately 100m
downstream of the site and continues to flow south of the reservoir towards Coed Bald.
There is also a minor, unnamed drain marking one of the field boundaries and several springs
rise to the west of the proposed development site, as illustrated in Figure 2-3.
Minor Road to Bettws
Figure 2-3 Catchment Hydrology (dark blue solid line indicates Pantyreos Brook; light blue solid
line indicates drainage ditch)
© Environment Agency copyright and database rights 2015. © Ordnance Survey Crown copyright. All
rights reserved. Environment Agency, 100026380. Contains Royal Mail data © Royal Mail copyright and
database right 2013.
The catchment incorporating the proposed development site receives an average rainfall of
1342mm and has a steep average slope of 182m/km. The British Geological Survey’s (BGS)
Geology Viewer describes the dominant bedrock geology within the local catchment as
Interbedded Argillaceous Rocks and Sandstone of the Maughans Formation, with no recorded
superficial deposits. Soils are defined by 1:250K soil mapping as well drained reddish fine silty
sands over shale and siltstone. There are also similar soils with slowly permeable subsoils prone
to slight seasonal waterlogging.
2.3 Development Proposals
The proposed development would consist of rows of solar panels comprising photovoltaic cells
mounted on an aluminium or steel supporting frame that is hammered or bored directly into the
ground.
The arrays of panels would be up to 3m high, with each panel being elevated approximately 0.6m
above ground level and orientated to the south at a 25-30 degree angle.
The rows (or ‘strings’) of panels would be set approximately 3.5m to 4.5m apart from each panel
edge. This distance would minimise the amount of overshadowing and also allow for maintenance
access.
Other ancillary infrastructure would include field transformers, inverter stations, a communication
building, a client side substation, a storage shed, a site transformer (AUX), a DNO substation, a
DNO meter and associated underground cabling.
Pantyreos Reservoir
Pantyreos Brook
Ditch
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The site would be secured around its perimeter with a 1.9m high woven mesh ‘deer’ fencing.
Security cameras and small motion detectors would be mounted on wooden posts.
Construction and maintenance traffic would use access tracks comprising a compacted stone
finish. It is considered that the ground beneath the strings of panels would be seeded to pasture.
The proposed development layout is shown in Appendix A.
3 Assessment Methodology
This assessment of flood risk has utilised existing data and information where available. These
data have been supplemented by a hydrological assessment to calculate the surface water runoff
characteristics of the site in its current form and in the developed scenario. Options for the
management of surface water runoff are also described.
3.1 Data Collection
Data have been collected from the following sources:
NRW Flood Map (NRW, 2015), accessed via http://naturalresourceswales.gov.uk/maps-
and-data/?lang=en;
Sheet 5 of the 1:250 000 Soil Map Series (Soil Survey of England and Wales, 1983)
BGS Geology Viewer, accessed via
http://mapapps.bgs.ac.uk/geologyofbritain/home.html;
The Flood Estimation Handbook CD-ROM (CEH, 2009);
Risk of Flooding from Surface Water on-line mapping (NRW, 2015), accessed via
http://naturalresourceswales.gov.uk/maps-and-data/?lang=en;
Risk of Flooding from Reservoirs on-line mapping (NRW, 2015), accessed via
http://naturalresourceswales.gov.uk/maps-and-data/?lang=en;
Torfaen County Borough Council Flood and Water Management Act 2010 Section 19
Flood Investigation Report - Cwmbran (2014);
Local Flood Risk Management Strategy (Torfaen County Borough Council, July 2013);
and
Local Development Plan (LDP), Broad Level Assessment of Flood Risk (Torfaen County
Borough Council, 2013).
3.2 Surface Water Runoff Calculations
To determine surface water runoff characteristics from the proposed development site,
calculations have been undertaken using the methodology set out in the latest release of the
Environment Agency (EA) Flood Estimation Guidelines (EA, 2015). This document presents an
update to the recommended method of deriving runoff estimates for small plots of land whereby
the Institute of Hydrology Report 124 (IH124) methodology is no longer advocated. Instead,
estimates derived using Flood Estimation Handbook (FEH) methods are scaled down from the
catchment to the plot scale.
Runoff rates under existing site conditions have been calculated for the 1 in 2 year, 1 in 30 year
and the 1 in 100 year return periods in accordance with EA requirements. Volumes of net
(effective) rainfall have also been calculated for existing and post development scenarios and
estimates of required attenuation storage volumes have been provided.
3.3 Flood Risk Assessment
Baseline flood risk arising from the following sources has been appraised using all available data
as set out above:
Fluvial;
Coastal;
Surface Water;
Groundwater; and
Artificial sources.
The potential for the proposed development to impact on third party flood risk has also been
assessed and options for the management of surface water runoff from the site have been
investigated.
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4 Technical Advice Note (TAN) 15
4.1 General
WG planning policy Technical Advice Note 15 (TAN 15) gives guidance to planning authorities on
‘Development and Flood Risk.’ In addition, Development Advice Maps (DAMs) have been
produced to accompany TAN 15 and are referred to in Section 4 of TAN 15.
The DAMs comprise three zones, which are described in Table 4-1 below. Zone C is based on
the NRW’s extreme flood outline, and is further sub-divided into C1 and C2 to describe the
presence of significant infrastructure, such as flood defences. Zone B reflects the British
Geological Survey’s drift data. Zone A is considered to be at little to no risk of fluvial or tidal/coastal
flooding.
Description of zone Zone Planning action
Considered to be at little or no risk of fluvial or tidal/coastal flooding
A No need to consider flood risk further
Surface water run-off from all new development
must be managed
sustainably
Areas known to have been flooded in the past evidenced by sedimentary deposits
B
Used as part of a precautionary approach to indicate where site levels should be checked against the extreme flood level. If site levels are greater than the adjacent extreme flood level there is no need to consider flood risk further
Environment Agency extreme flood outline
Areas of the floodplain which are developed and served by significant infrastructure, including flood defences
C1
Used to indicate development can take place subject to application of the justification test, including assessment of flooding consequences (the justification test is detailed in section 6 of TAN 15)
Areas of the floodplain without significant flood defence infrastructure
C2
Only less vulnerable development should be considered here, subject to application of the justification test, including assessment of flooding consequences
Table 4-1 Development advice zones and associated planning actions (based on Figure 1 of TAN
15)
TAN 15 states that developers and Local Authorities should try to locate new development on
land in zones with the lowest probability of flooding. A risk-based approach to determining the
suitability of land for development in flood risk areas is central to TAN 15 and should be applied
at all levels in the planning process.
4.2 DAM Zone Categorisation
An extract of the DAM for the study area is presented in Figure 4-1. The development site is
shown to be wholly located within Zone A, where there is considered to be little or no risk of fluvial
(main river) or tidal/coastal flooding.
Figure 4-1 TAN 15 Development Advice Map (DAM) for the development site (outlined in red)
© Crown Copyright and database right 2011. Ordnance Survey 100017916.
Section 5 of TAN 15 provides guidance on the type of development appropriate for each Flood
Zone by categorising development according to the vulnerability of flooding. There are three
categories which include emergency services, highly vulnerable development and less vulnerable
development.
TAN 15 does not explicitly define the flood risk vulnerability of renewable energy developments
such as solar parks. Therefore, it has been considered, through consultation with NRW, that the
proposed development is classified as ‘Less Vulnerable’. The existing Zone A classification
therefore indicates that the site is suitable for the proposed use.
4.3 Sequential Test
The aim of the Sequential Test is to steer new development to areas with the lowest probability
of flooding. The proposed development site is located within Zone A and would therefore satisfy
the requirements of this Test as outlined in Section 6 of TAN 15. Application of the Justification
Test is not applicable at this site.
4.4 Need for a FCA
TAN 15 states that development for 'Less Vulnerable' land uses is appropriate in Flood Zone A.
However, the advice states that surface water run-off from all new development must be
demonstrated to be sustainably managed. A FCA has therefore been produced that focuses on
the assessment of flood risk from sources other than fluvial flooding and the management of
surface water runoff.
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5 Potential Sources of Flood Risk
An assessment of the potential for flooding of the proposed development site from a wide range
of sources has been undertaken. This is summarised in the following sections.
5.1 Historic Flooding
The BHS Chronology of British Hydrological Events web site1 is a public repository for hydrological
facts. It attempts to provide as much material as possible so that the spatial extent of flood events,
and their relative severity, can be assessed. A search of the website has been undertaken and
no records of flooding local to the proposed development site have been identified.
Consultation with Torfaen County Borough Council (in its role as Lead Local Flood Authority
(LLFA)) and NRW has been undertaken to request records of historical flood incidents for the
proposed development site. However, this information has not been provided to date.
5.2 Fluvial Flood Risk
The DAM indicates that the proposed development site is located within Flood Zone A and fluvial
flood risk from Main River sources is therefore considered to be negligible.
There are no ordinary watercourses located within the application boundary of the site. The
Pantyreos Brook flows to the west of the proposed development. However, this watercourse has
a well defined channel with steeply sloping banks as illustrated in Plate 5-1 below.
Given that the watercourse has good flow conveyance properties, a small catchment area
(approximately 1km2) and the proposed development site is located on higher ground relative to
the watercourse, it is considered that the risk of fluvial flooding to the proposed development site
from the Pantyreos Brook is negligible.
Plate 5-1 Photograph taken by Hyder Consulting, facing north with bank sloping down towards the
Pantyreos Brook
It is therefore considered that the risk of fluvial flooding from both Main River and ordinary
watercourses is negligble.
5.3 Coastal Flood Risk
The site is located at an elevation exceeding 145m AOD.
It is therefore considered that there is no coastal flood risk to the proposed development
site.
5.4 Surface Water
At greenfield sites such as the proposed development site, surface water flooding is a potential
risk during short, intense rainstorm events or longer duration storms, when the infiltration capacity
of the underlying soils is exceeded and rainfall runs off steeper slopes to pond in lower lying,
flatter areas.
Data on existing surface water flood risk has been gathered from a dataset published by NRW in
December 2013. An extract of the on-line mapping for the study area is provided in Figure 5-1.
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Figure 5-1 Extract of the NRW Surface Water Flood Map (proposed site location shown as a red
line)
© Environment Agency copyright and database rights 2015. © Ordnance Survey Crown copyright. All
rights reserved. Environment Agency, 100026380. Contains Royal Mail data © Royal Mail copyright and
database right 2015.
This shows that the entirety of the proposed development site falls within the ‘very low’ category
of risk, which is indicative of a chance of surface water flooding each year of less than 0.1% (1 in
1000).
The LDP Broad Level Assessment of Flood Risk (Torfaen County Borough Council, 2013) also
states that Cwrt Henllys Farm (approximately 100m from the site) has no risk from surface water
flooding.
Therefore, it is considered that the risk of surface water flooding to the proposed
development site is negligible.
However, the introduction of impermeable surfaces associated with development of a greenfield
site may increase surface water flood risk to third parties. It is particularly important that
consideration is given to the management of surface water runoff and to changes in surface water
runoff patterns as a result of construction of the proposed development. The management of
surface water from the proposed development is considered further in Section 6.
5.5 Groundwater
Groundwater flooding occurs when groundwater rises to the ground surface. This may happen
during winter and / or after prolonged or heavy rain storms.
There are no records of groundwater flooding having affected the proposed development site.
BGS mapping shows that the site is not underlain by superficial geological deposits and the
bedrock geology comprises Sandstone formations which have the potential to store and convey
groundwater.
Consultation with TCBC has identified no concerns regarding groundwater flooding on the site.
Given the steeply sloping topography of the site and the low vulnerability of the proposed
development to this source of flood risk it is concluded that flood risk from groundwater
is minor.
5.6 Artificial Sources
Pantyreos reservoir is located approximately 100m south of the development site. The reservoir
has a total area of 6.44 ha. Since the site is located upslope of the reservoir, it is considered that
there is no risk of flooding from this source.
The EA’s maximum extent of flooding from reservoirs does not extend to the proposed
development boundary, as illustrated in Figure 5-2.
Figure 5-2 EA Risk of flooding from Reservoirs (site in red outline)
© Environment Agency copyright and database rights 2015. © Ordnance Survey
Crowncopyright. All rights reserved. Environment Agency, 100026380. Contains Royal
Mail data © Royal Mail copyright and database right 2015.
There are no other artificial waterbodies in the vicinity of the proposed development site and it is
therefore concluded that there is no flood risk from artificial sources.
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6 Surface Water Drainage Assessment
6.1 Planning Policy Requirements
Current flood risk and development planning policy specifies that surface water arising from a
developed site should, as far as is practicable, be managed in a sustainable manner to mimic the
surface water flows arising from the site prior to the proposed development. Opportunities to
reduce flood risk to the site itself and elsewhere, taking climate change into account, should be
investigated and this should be demonstrated as part of the FCA. Developers should seek
opportunities to reduce the overall level of flood risk through appropriate application of
Sustainable Drainage Systems (SUDS). As well as restricting discharge rates and run-off
volumes, SUDS can provide a means of improving water quality, wildlife and amenity value.
6.2 Existing Drainage
The runoff regime of the existing unsewered site is governed by topography, soil drainage
parameters and ground cover type. When the soils are saturated, runoff generated by excess
rainfall will follow the natural slope of the land, towards the south of the proposed development
site and the Pantyreos Brook.
Greenfield Runoff Rate Calculations
As mentioned in Section 3.2, current Greenfield rates of runoff from the proposed development
site have been calculated using the FEH Statistical method. The results of these calculations are
presented in Table 6-1.
Table 6-1 Greenfield runoff calculation results
Return Period Event Greenfield Runoff Rate
(litres/second/hectare)
1 in 2 year 6.5
1 in 30 year 12.4
1 in 100 year 15.3
6.3 Effects of the Proposed Development
Rainwater falling onto the solar panels would drain freely to the ground beneath. Thus, the total
surface area of the photovoltaic strings is not considered to represent an impermeable area in
terms of this assessment. Furthermore, the runoff would be ‘clean’ water, suitable for direct
discharge to the ground. Most of the site would remain as ‘soft’ surface, with pasture surrounding
and underneath the photovoltaic panels.
Access tracks would be formed using compacted stone/gravel. These tracks, together with the
ancillary infrastructure which would include a number of transformers housing electrical
equipment, have a small combined impermeable footprint of approximately 0.14ha. This
impermeable coverage represents just 1% of the total area of the site.
It is concluded, therefore, that the runoff regime for the proposed development is likely to be
similar to that for the existing land use, given the minimal new impermeable surface area which
is to be introduced.
Rainfall Runoff Volume Calculations
An indicative assessment has also been completed to quantify the impact of the proposed
development on rainfall runoff volumes. In particular, the Revitalised Flood Hydrograph method
(ReFH), part of the suite of FEH techniques, has been used to simulate a rainstorm over the study
catchment with a 6 hour duration and 1 in 100 year return period, in line with CIRIA C609
guidelines. The Design Rainfall is the amount of rain that is predicted to fall on the proposed
development site during this event. The Net Rainfall is the portion of the Design Rainfall which
contributes to surface water runoff, taking account of losses due to evaporation, soil moisture
retention and depression storage.
To quantify the effect of the proposed development on rainfall runoff volumes, it has been
assumed that no losses would occur when rain falls over the impervious surfaces, such as the
roofs of the transformers housing electrical equipment (i.e. these areas contribute Direct Rainfall).
Those areas not covered by impermeable surfacing would encourage losses, with rainfall volume
contributions calculated from Net Rainfall depths. With regard to the internal site access tracks,
which would be formed of gravel/stone, a percentage runoff from these areas of 40% has been
applied in the runoff volume calculations. The results of the calculations are presented in Table
6-2.
Table 6-2 Rainfall Runoff volumes (1 in 100 year 6 hour storm duration)
Notes: *assuming 40% runoff from gravel access tracks, excluding the temporary construction compound
Permeable
Area (m2)
Impermeable
Area (m2)
Volume of rainfall
runoff (m3)
Existing Site 143,180 - 3072
Post Development 142,618 622* 3100
An additional volume of rainfall runoff of approximately 28m3 is estimated to be generated as a
result of the proposed development. Further details of the calculations are provided in Appendix
C.
Climate Change
In accordance with TAN 15 guidelines, the impacts of climate change have also been considered,
with an increase in peak rainfall intensity of 30% applied to the 100 year 6 hour storm.
Taking into account the climate change scenario, the proposed increase in impermeable surface
coverage results in an increase in runoff volume equal to 37m3.
6.4 Drainage Strategy
Although it is considered that the proposed development would have a minor impact on the
existing surface water runoff regime, SUDS would nevertheless be integrated into the
development. In particular, it is proposed that trackside and boundary swale features are used to
attenuate the additional volumes of runoff generated by the new impermeable surfaces, as
indicated in Figure 6-1. These swale features would be designed to ensure that the proposed
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development does not increase overland flow from the site onto third party land, compared to
existing conditions, in a 1 in 100 year rainfall event allowing for climate change impacts.
Infiltration is the preferred method of disposal of the storm water collected by the swales.
However, it is recommended that the viability of infiltration drainage is confirmed via soakaway
testing.
The long-term management and maintenance responsibilities for the proposed SUDS scheme
would lie with the applicant. It is recommended that, as a minimum, maintenance should include
inspection and cleaning, to ensure the capacity of the SUDS features and infiltration levels are
maintained.
Figure 6-1 Site plan highlighting indicative location of boundary swale features (Purple lines)
and trackside swale features (pink lines)
7 Summary
The proposed development site is located in Flood Zone A of the Welsh Government’s
development advice maps (DAM). Use of the site as a solar farm is therefore in accordance with
latest government planning policy on development and flood risk (TAN 15).
All sources of potential flood risk to the proposed development site have been assessed. The site
is not considered to be at risk of flooding from coastal, groundwater or artificial sources. And, the
proposed development would not increase the risk of flooding from these sources.
Fluvial flood risk from Main River and ordinary watercourses has been assessed as low and the
proposed development would not increase the risk of fluvial flooding to third parties.
Although the proposed development site is bordered in the east by a small drainage ditch, the
catchment area of this ditch is small and therefore flooding associated with this watercourse is
likely to be very limited.
The proposed development site is classified as being at very low risk of surface water flooding.
The proposed development would result in a small increase in coverage by built development and
impermeable surfaces (1%) which result in an increased runoff of 28 m3.
Runoff from the new impermeable surfaces would be managed using a range of SUDS features,
selected to suit the local site conditions. The SUDS would be designed to ensure that existing
(greenfield) rates of runoff are maintained post-development, and that the natural drainage regime
is preserved.
In summary, the proposed development is not considered to increase flood risk on site, or
elsewhere.
Appendix A
Site Location Plan and Proposed Development Layout
Field Boundary
Security Fence
Overhead Line
Site Access
Access Road
Compound Area
Inverter Station
DNO Substation
Site Boundary
Field Transformer
DNO Meter
Client Side Substation
Communications Building
Site Transformer (Aux)
CCTV
Access Gates
Tree
Module Table 11 x 3
Module Table 22 x 3
Temporary Access Road
Storage Shed
WC
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Revisions:
Rev Date ChkdDwnComments
DAFence moved in North and South boundaries25/07/154
MPRed line has been modified22/07/153
DATopo added, boundary changed13/07/152
NVEastern field removed / DNO moved17/06/151
NOTES:
-
-
-
-
Lightsource Renewable Energy Holdings Ltd, 7th Floor,
33 Holborn, London, EC1N 2HU
General: +44 (0) 333 200 0755
Web: www.lightsource-re.co.uk
PROJECT NAME & ADDRESS:
DRAWING TITLE:
DRAWING NUMBER:
Scale:Paper Size:
Sheet:
STATUS:
CAPACITY:
DRAWN CHECKED APPROVED DATE
PreliminaryCWH_01_Rev04
4.99851 MWp
Cwrt Henllys_Proposed_Layout_Rev04
11:2500@A3A3
Location: Henllys, Cwmbran
3° 4'37.61"W
51°37'18.64"N
Postcode: NP44 7AS
NV XX XX 16.06.15
Cwrt Henllys_Proposed_Layout_Rev04
Scale 1:7500
Area 143,180 m2 (35.38 acres)
Appendix B
Site Topography
157.88
SURVEY STATIONS
Name
M1
M2
M3
M4
Easting
325572.959
325436.215
325324.474
325417.432
Northing
192094.047
191996.862
191913.694
191856.742
Height
176.098
176.922
174.891
157.015
178.00
179.0
0180.00
181.0
0
182.0
0
183.0
0
184.00
185.00
186.00
187.00
188.00
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.0019
7.00
168.0
0
169.00
170.00
171.0
0
172.001
73.00174.00175.00176.00177.00178.00
179.00
180.00
181.00
182.00
183.00
184.00
185.0018
6.0018
7.0018
8.0018
9.00
190.00
191.00
192.0
0
193.0
0
144.00
145.00
146.00
147.00
148.00
149.00
150.00
151.00
152.0
0
153.00
154.00
155.00
156.00
157.00
158.00
159.0
0
160.0
0
161.00
162.00
163.00
164.00
165.00
166.00
167.00
152.00
153.00
154.00
155.00
156.00
157.0
0
158.0
0
159.0
0
160.00
161.00
162.00
163.00
164.00
165.00
166.00
167.00
168.00
169.00
170.00
171.00
172.00
173.00
174.00
175.00
176.00
177.00
178.00
179.00
180.00
181.00
182.00
183.00
184.00
185.00
186.00
187.00
188.00
189.00
190.0
0
191.00
192.00
169.0
0
170.00
171.00
172.0
0
173.0
0
174.00
175.0
0
176.0
0
177.0
0
178.0
0
179.0
0
180.0
0
181.0
0
182.0
0
183.0
0
184.00
185.00
186.00
187.00
188.00
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
197.00
198.00
199.0020
0.00
146.0
0
147.0
0
148.0
0
149.0
0
150.0
0
151.0
0
152.0
0153.0
0154.0
0
155.0
0
156.0
0
157.0
0
158.0
0
159.0
0
160.0
0161.0
0162.0
0163.00
164.0
0
165.00
166.00
167.00
146.00
147.00
148.0
0
149.0
0
150.0
0
151.0
0
152.00
153.00
154.00
155.00
156.00
157.00
158.00
159.00
160.00
161.00
162.00
163.00
164.00
165.00
166.00
167.00
168.00
169.00
171.0
0
172.00
173.00
174.00
175.0
0
176.0
0
177.0
0
178.00
179.00
180.00
181.00
182.00
183.0
0
184.0
0
185.0
0
186.0
0
187.0
0
188.0
0
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
197.00
198.00
199.0
0
200.0
020
1.00
171.00
172.00
173.00
174.00
175.00
176.00
177.00
178.00
179.00
180.00
181.0
0
182.00
183.00
184.00
185.00186.00
187.00
188.00
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
197.00
198.00
199.00
153.00
153.0
0
154.00
155.0
0
156.00
157.00
158.00159.00160.00161.0
0162.00
163.00164.00165.00
166.00
167.00
168.00
169.00
154.00
155.00
156.00
157.00
158.00
159.00
160.00
161.00
155.00
156.00
157.00
158.00
159.00
160.00
161.00
162.00
163.00
164.00
161.00
162.00
163.00
164.00
165.00
166.00
167.00
168.00
169.00
170.0
0
171.00
172.00
173.0
0
174.00
175.00
173.00
174.00
175.00
176.0
0
177.0
0
178.0
0
179.0
0
180.0
0
181.00
182.00
183.0
0
184.00
185.00
186.00
187.00
188.00
189.00
190.00
191.00
178.0
0
179.0
0
180.00
181.00
182.0
0
183.0
0
184.0
0
185.0
0
177.00
178.00
179.0
0
180.0
0
181.0
0
182.00
183.00
142.5
5
142.85
Post & Rail H
eight=1.1m
143.7
8144.25
Barb
wire & M
esh Height=1.0
m
144.91
Barbwire & Mesh Height=1.05m
145.05
Barbwire & M
esh Height=1.05m
Barbw
ire & Mesh H
eight=1.05m
Barbw
ire & Mesh H
eight=1.05m
145.1
3
145.1
4
145.27
145.32
145.47
145.62
145.77
146.14
146.16
146.3
3
146.5
1
146.58
146.61
Tre
e C
anopy
146.84
146.87
146.88
146.88
146.89
147.06
147.17
147.28
147.53
147.59
147.60
TP
148.09
148.19
148.45
148.49
148.50
148.65
148.67
148.88
TP
149.0
6
149.34
149.35
149.35
149.40
149.44
149.49
149.50
149.6
5
150.02
150.02
150.18
150.22
150.4
2
150.56
150.62
150.70
Overh
ead Level= 1
50.7
40
m
150.82
150.89
150.89
150.93
150.99
151.08
151.10
151.12
151.16
151.30
Overh
ead Level= 1
51.4
12
m
151.48
Tre
e C
anopy
151.76
151.85
151.87
Barbwire & M
esh Height=1.25m
152.01
152.06
152.10
152.13
152.39
152.45
152.47
152.47
152.49
152.50
152.52
152.59
152.71
152.87
152.88153.12
153.17
153.43
153.56
153.56
153.61
153.62
153.62
153.71
153.84
154.03
154.04154.05
154.07
154.10
154.11
154.30
154.31
154.35
Tree Canopy
154.47154.57154.61
154.74
154.76
154.78155.04
155.06
155.10
155.16
Barb
wire & M
esh Height=0.9
m
155.18
Barbwire & Mes
h Height=0.9m
155.31
155.35
155.42
155.52
155.58
155.60
155.64
155.95
156.00
156.04
156.07
156.38
156.39
156.42
156.54
156.61
156.62
156.66
TP
156.87
157.01
M415
7.09
157.13
157.15
157.15
Barbwire & Mesh Height=1.050m
157.20
157.27
157.30
157.35
157.36
157.45
157.55
157.58
157.64
157.66
157.70
157.74
Overhead Level= 1
57.8
21
m
157.85
158.02
158.23
158.29
158.31
158.38
158.39
158.45
158.47TP
158.79
158.88
158.93
158.96
159.05
159.18
159.19
159.26
159.35
159.37
159.39
159.40
159.42
159.44
159.47
159.70
159.71
Pasture
159.72
159.82
159.91
160.01
160.21
160.24
160.29
160.31
160.38
160.42
160.42
160.47
160.60
160.90
160.95
160.96
160.98
161.09 161.20
Tree Top 161.33
161.34
161.40
161.48
161.48
161.52
161.55
161.58
161.64
161.68
161.74
161.74
161.78
161.78
161.88
161.93
161.94
162.03
162.03
162.12
162.16
162.17
162.17
162.20
162.33
Tree Top 162.34
162.39
162.43
Tree Top 162.45
162.45
162.56
162.73
162.73
162.74
162.86
162.88
162.92
Pasture
162.93
Tree Top 177.94
163.06
163.11
163.18
163.26
163.30
163.32
163.46
163.48
163.50
163.53
Overhead Level= 1
63.6
46
m
163.75
163.76
163.80
163.88
163.93
163.99
164.05
Tree Top 170.75
164.25
164.29
164.41
164.52
Tree Top 164.53
164.58
164.65
Tree Top 164.67
164.75
Tree Top 164.83
164.88
164.88
164.90
164.92
Tree Top 170.17
165.05
165.06
165.13
165.21
165.27
165.36
Tree Canopy
165.47
Tree Top 169.11
165.84
165.85
165.94
165.96
166.00
166.03
TP
166.25
166.36
166.40
166.43
166.49
166.63
166.67
166.72
166.79
166.84
166.87
166.91
166.91
166.93
Overhea
d Le
vel= 167.039
m
167.09
167.27
167.39
167.50
167.57
167.58
167.62
167.80
167.90
167.97
168.00
168.16
Tree Top 168.22
168.2
4
168.25
168.27
168.28
168.30
168.30
168.36
Tree Top 168.39
168.41
168.46
TROUGH
168.56
168.58
Tree Top 168.58
Tree Top 168.66
168.75
Post & Rail
Height=1m
168.77
168.77
Tree Top 168.78
Tree Top 168.79
168.85
168.89
168.92
168.97
Tree Top 168.98
169.00
169.05
Barbwire & Mesh Height=1.25m
169.20
169.21
169.21
Tree Top 176.29
169.41
Tree Top 174.76
169.60
169.64
Barb
wire & M
esh Height=0.850m
169.65
169.71
169.82
169.83
169.86
169.87
169.88
169.88
Tree Top 169.95
Post
& Rail H
eight=1.1
m
169.9
9
170.02
170.05
170.11
170.17
170.19
Barb
wire & M
esh Height=1.25m
170.20
170.34
170.35
170.38
170.41
170.42
Tree Top 170.50
Tree Top 170.52
170.67
170.70
170.71
170.76
170.77170.85
170.95
170.97
170.97
Tree Top 170.97
170.97
171.06
171.09
171.09
171.12
171.16
Tree Top 171.25
171.31
171.32
171.35
171.36
171.42
171.43
Tree Canopy
Tree Top 171.55
171.59
171.59
171.84
171.89
172.03
172.03
172.07
172.17
Tree Top 172.27
172.30
172.40
172.42
172.49
172.57
172.59
Tree Top 172.78
Tree Top 172.78
172.79
172.91
173.01
173.01
173.06
173.08
173.19
173.19
Tree Top 173.21
Tree Top 173.24
173.28
173.39
173.46
173.51
173.51
Tree Top 173.51
173.63
173.65
173.77
Tree Top 173.94
173.95
173.97
174.02
Tree Top 174.04
174.05
174.27
174.29
174.33
174.33
Tree Top 174.35
174.37
174.37
174.46
174.49
174.54
Tree Top 174.61
174.63
Tree Top 174.67
Tree Top 174.70
174.73
174.77
174.80
174.85
Barbwire & Mesh Height=1m
174.87
M3
Tree Top 174.94
175.03
175.04
175.08
175.20
175.40
Tree Top 175.42
Tree Top 175.56
175.63
175.63
175.67
175.72
175.73
175.75
175.85
175.94
175.94
176.03
176.06
Tree Top 176.12
Tree Top 176.16
176.22
Tree Top 176.28
176.34
176.35
176.35
176.36
TR
OU
GH
176.60
176.62
Tree Top 176.65
176.76
176.8
0
176.82
176.82
176.85
M2
176.97
Tree Top 176.97
Barb
wire Wire
mes
h Height=1.0m
177.03
177.12
177.15
177.16
177.22
177.27
177.27
177.28
177.29
177.35
177.37
Tree Top 177.40
177.44
177.44
Tree Top 177.45Tree Top 177.45
177.47
177.47
Tree Top 177.47
177.47
177.56
177.58
177.60
177.62
Post & Rail Height=1m
177.64
177.67
Tree Top 177.78
177.89
Tree Top 177.92Tree Top 177.95
177.95
178.02
178.03
178.03
Barb
wire & M
esh Height=1m
178.06
178.08
178.10
178.14
178.29
Post & Rail Height=1.05m
Tree Top 178.41
Tree Top 178.56
178.58
178.61
Tree Top 178.64
Tree Top 178.68
178.76
178.87
178.89
Tree Top 178.91
178.94
178.98
179.14
179.24
179.32
Tree Top 179.34
Tree Canopy
Tree Top 179.40
Barbw
ire & Mesh H
eight=1.1m
179.43
179.43
Tree Top 179.46
179.48
179.48
Post & Rail Height=1.05m
179.51
179.54
179.60
179.60
179.60
179.63
Tree Top 179.73
179.80
179.87
179.89
179.90
179.92
179.96
180.03
180.28
180.29
180.35
180.36
Tree Top 180.37
180.37
180.39
Ditch180.50
180.76
180.78
181.07
181.11
Tree Top 181.11
181.18
Tree Top 181.20
181.24
Tree Top 181.25
181.27
181.29
Tree Top 181.30
181.39
181.42
181.45
181.54
181.56
181.57
181.58
181.59
181.61
Tree Top 200.99
181.71
181.80
181.93
182.08
182.11
Tree Top 182.16
182.17
Tree Top 182.48
182.55
Tree Top 182.63
182.66
182.66
182.72
182.75
Tree Top 182.77
182.93
182.93
182.95
183.10
183.14
183.17
183.26
183.31
183.38
183.39
183.46
183.76
183.78
183.85
183.88
184.00
184.01
184.07
184.10
184.27
184.35
184.38
184.58
Pasture
184.60
184.70
184.73
184.76
184.83
184.85
184.88
184.92
185.05
Tree Top 185.49
185.57
185.57
Tree Top 185.61
185.62
185.63
185.91
Tree Top 185.91
185.93
185.93
Tree Top 185.95
Tree Top 186.01
186.08
Tree Top 186.20
186.24
186.24
186.30
186.34
186.64
Tree Top 186.72
186.76
186.87
186.88
186.89
186.99
187.05
Tree Top 187.09
187.27
187.42
187.62
187.83
187.87
187.92
188.01
Tree Top 188.07
188.16
188.22
188.27
188.32
188.35
188.39
188.51
188.58
Pasture
188.71
Tree Top 188.73
188.76
188.85
Tree Top 188.97
189.12
189.23
189.39
189.52
189.52
189.53
189.53
189.77
189.79
Tree Top 189.91
189.96
Tree Canopy
190.15
190.16
Hedge top190.24
190.37
190.45
190.52
190.54
190.62
190.66
190.79
190.90
190.91
191.12
191.14
191.29
191.36
Tree Top 191.48
191.48
191.52
191.56
191.57
191.72
191.95
191.96
192.09
Tree C
anopy
192.17
192.22
192.24
192.28
192.31
192.36
192.46
192.51
192.54
192.57
192.64
192.72
192.72
192.89
192.94
192.94
Tree Top 193.31
193.38
193.48
193.56
193.72
193.77
193.88
Electric F
ence
193.89
Tree Canopy
194.00
194.01
194.06
194.30
194.34
194.53
Barbw
ire & Mesh H
eight=1m
194.61
194.67
194.67
194.69
194.79
194.93
195.06
195.07
195.18
195.30
Tree Top 195.34
195.45
195.46
195.56
Tree Top 195.65
195.83
196.06
196.10
196.13
196.41
196.44
196.45
196.45
196.47
Tree Top 196.63
196.66
196.71
196.86
196.92
Tree Canopy
197.0
3
197.45
197.59
197.71
197.72
Tree
Can
opy
197.9
3
198.04
198.04
198.26
198.26
198.31
198.37
198.46
198.68
198.71
Electric Fence
198.97
199.06
199.19
Tree
Can
opy
Tree Top 199.44
199.45
Ditch
Tree Canopy
199.77
199.80199.82
199.88
199.88
199.89
199.97
200.18
Tree Top 200.40
200.51
201.18
201.37
Barbwire & Wire
mes
h Ht=1.1m
201.40
Barbwire & Wire
mes
h Ht=1.1m
201.74
Tree Top 202.55
Tree Top 203.60
Tree Top 204.66
Tree Top 204.71
Tree Top 205.13
Tree Top 205.25
Tree Top 205.27
Tree Top 207.01
Tree Top 207.20
Tree Top 207.27
Tree Top 207.33
Tree Top 207.52
Tree Top 207.59
Tree Top 207.96
Tree Top 208.77
Tree Top 209.29
Tree Top 209.86
Tree Top 209.87
Tree Top 211.29
Tree Top 212.29
Tree Top 213.91
Tree Top 214.52
Tree Top 214.91
Tree Top 215.72
Tree Top 216.77
Tree Top 217.72
Tree Top 218.81
Tree Top 219.38
Tree Top 220.40
Tree Top 220.50
Tree Top 221.09
Tree Top 221.97Tree Top 221.97
Tree Top 228.86
Tree Top 232.30
Long Grass
Long Grass
Long Grass
Long Grass
Long Grass
Long Grass
Long Grass
N
Scale Factor = 1
Projection OSTN02 and OSGM02
Grid and Levels to National Grid
CLIENT JOB TITLE
Sheet 1
NP44 7AS
Cwmbran
Henllys
Cwrt Henllys Farm
Topographical Survey
EC1N 2HT
London
33 Holborn
7th Floor
Lightsource Renewable Energy Ltd
REVISIONS
SCALE
DATE SURVEYED BY
CHECKED BY
DRAWING No.
A0 Sheet @ 1 to 500
15732-200-01T Sheet 1
MC PAH
MCJuly 2015
BL
BS
BT
DP
EP
EB
FH
FP
GY
GV
Ht
Bollard
Bus Stop
Telecom Cover
Down Pipe
Electricity Pole
Fire Hydrant
Fence Post
Gulley
Gas Valve
Height
Kerb Inlet
Electricity Box
LC
MK
MW
RP
RS
SA
TL
TP
VP
WM
WO
Lamp Column
Marker Post
Reflector Post
Road Sign
Soak Away
Traffic Light
Telegraph Pole
Vent Pipe
Water Meter
Wash Out
Monitoring Well
UTS Unable to Survey
AV Air Valve
CATV Cable TV Cover
EY Electricity Cover
Gate PostGP
FFL Finished Floor Level
THL Threshold Level
CL Cover Level
CP Catch Pit
CR Cable Riser
Depth in Meters
Invert Level
MH Manhole
MK Marker Post
MS Mile Stone
OHC Overhead Cable
PB Post Box
BB Belisha Beacon
PostPO
RE Rodding EyeER Earth RodRNP Road Name Plate
SC Stop Cock (Water)
SD Sump Depth
Silt Silt Level
Sign PostSP
SV Stop Valve (Water)
WL Water Level
NPV No Pipe Visible
EOT End of Trace
UTL Unable to Lift
UTT Unable to Trace
TS Traffic Sign
BH Bore Hole
BT CAB Telecom Cabinet
EIC Electrical Inspection Cover
ECAB Electrical Cabinet
Bin Litter Bin
MK-BT Marker Post (Telecoms)
MK-FH Marker Post (Fire Hydrant)
MK-GV Marker Post (Gas Valve)
MK-SV Marker Post (Stop Valve)
MK-WM Marker Post (Water Meter)
MYIC Mercury Telecoms IC
SL Soffitt Level
TVIC Cable TV Inspection Cover
TL CAB Traffic Light Cabinet
Ground Penetrating RadarGPR
D
IL
KI
LEGEND
Brunel Surveys LtdUNIT 59, SHRIVENHAM HUNDRED BUSINESS PARK
WATCHFIELD, SWINDON, WILTSHIRE, SN6 8TZ
TEL : (01793) 784700 FAX : (01793)784664
WEB : www.brunelsurveys.com
Email:[email protected]
Underground Utility Surveyors
Photomontage, 3D Visualisations and
Land and Measured Building Surveyors
DRAWN BY
191700N
191750N
191800N
191850N
191900N
191950N
192000N
325050E
325100E
325150E
325200E
325250E
325300E
325350E
325400E
325450E
325500E
325550E
Sheet 1
Sheet 2
179.24
157.88
325050E
325100E
325150E
325200E
325250E
325300E
325350E
325400E
325450E
325500E
325550E
SURVEY STATIONS
Name
M1
M2
M3
M4
Easting
325572.959
325436.215
325324.474
325417.432
Northing
192094.047
191996.862
191913.694
191856.742
Height
176.098
176.922
174.891
157.015
185.0018
6.0018
7.0018
8.0018
9.00
190.00
191.00
192.0
0
193.0
0
190.0
0
191.00
192.00
176.0
0
177.0
0
178.0
0
179.0
0
180.0
0
181.0
0
182.0
0
183.0
0
184.00
185.00
186.00
187.00
188.00
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
197.00
198.00
199.0020
0.00
165.00
166.00
167.00
168.00
169.00
171.0
0
172.00
173.00
174.00
175.0
0
176.0
0
177.0
0
178.00
179.00
180.00
181.00
182.00
183.0
0
184.0
0
185.0
0
186.0
0
187.0
0
188.0
0
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
197.00
198.00
199.00
200.0
020
1.00
171.00
172.00
173.00
174.00
175.00
176.00
177.00
178.00
179.00
180.00
181.0
0
182.00
183.00
184.00
185.00186.00
187.00
188.00
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
197.00
198.00
199.00
200.0020
1.00
157.00
158.00159.00160.00161.0
0162.00
163.00164.00165.00
166.00
167.00
168.00
169.00
157.00
158.00
159.00
160.00
161.00
156.00
157.00
158.00
159.00
160.00
161.00
162.00
163.00
164.00
161.00
162.00
163.00
164.00
165.00
166.00
167.00
168.00
169.00
170.0
0
171.00
172.00
173.0
0
174.00
175.00
173.00
174.00
175.00
176.0
0
177.0
0
178.0
0
179.0
0
180.0
0
181.00
182.00
183.0
0
184.00
185.00
186.00
187.00
188.00
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
197.00
198.00
199.00
200.00
201.00
202.00
178.0
0
179.0
0
180.00
181.00
182.0
0
183.0
0
184.0
0
185.0
018
6.00
187.00
188.00
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
197.00
198.00
199.00
200.00
177.00
178.00
179.0
0
180.0
0
181.0
0
182.00
183.00
184.00
185.00
186.0
0
187.0
0
188.00
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
198.00199.0020
0.00
201.00
202.00
178.0
0
179.0
0
180.0
0
181.00
182.00
183.00
184.0
0
185.00
186.00
187.00
188.00
189.00
190.00
191.00
192.00
193.00
194.00
195.00
196.00
197.00
198.00
199.00
200.00
201.00
177.0
0
178.00
179.00
180.00
181.00
182.00
183.00
184.00
185.00
186.00
187.00
188.00
189.00
190.0
0
191.0
0192.0
0
193.00
194.0
0
195.0
0
196.0
0
197.0019
8.00
199.00
200.00
201.00
Barbwire & Mes
h Height=0.9m
156.04
156.07
156.38
156.61
157.01
157.27
157.30
157.35
157.45
157.66
157.74
157.85
158.02
158.23
158.29
158.31
158.39
158.45
158.88
159.18
159.19
159.26
159.35
159.37
159.47
159.71
159.91
160.24
160.29
160.38
160.42
160.47
160.60
160.96
161.09 161.20
161.34
161.40
161.48
161.48
161.52
161.55
161.64
161.74
161.74
161.78
161.93
161.94
162.03
162.12
162.17
162.33
162.45
162.56
162.86
162.88
162.92
Pasture
162.93
163.11
163.26
163.32
163.48
163.50163.75
163.88
164.05
Tree Top 170.75
164.29
164.41
164.52
164.58
164.65
164.90
Tree Top 170.17
165.05
165.06
165.21
165.47
Tree Top 169.11
166.00
166.03
TP
166.43
166.63
166.72
166.84
166.91
Overhea
d Le
vel= 167.039
m
167.09
167.27
167.50
167.62
167.90
167.97
168.16
Tree Top 168.22
168.2
4
168.25
168.28
168.30
168.41
Tree Top 168.58
Tree Top 168.66
Post & Rail
Height=1m
168.77
Tree Top 168.78
Tree Top 168.79
168.85
168.89
168.92
168.97
Barbwire & Mesh Height=1.25m
169.21
Tree Top 176.29
169.41
Tree Top 174.76
169.71
169.82
169.83
169.88
169.88
Tree Top 169.95
Post
& Rail H
eight=1.1
m
169.9
9
170.11
170.17
170.19
Barb
wire & M
esh Height=1.25m
170.20
170.34
170.41
170.42
Tree Top 170.50
170.67
170.71
170.76
170.77170.85
170.95
170.97
170.97
Tree Top 170.97
171.06
171.09
171.12
Tree Top 171.25
171.31
171.32
171.35
171.36
171.43
Tree Top 171.55
171.84
171.89
172.03
172.07
172.17
172.30
172.42
172.49
172.57
172.59
Tree Top 172.78
172.79
172.91
173.01
173.06
173.19
173.19
173.28
173.39
173.51
173.51
173.63
173.65
Tree Top 173.94
173.95
174.02
174.05
174.27
174.29
174.33 Tree Top 174.35
174.37
174.46
174.54
174.63
174.73
174.85
Barbwire & Mesh Height=1m
174.87
M3
175.03
175.04
175.08
175.20
175.40
Tree Top 175.42
Tree Top 175.56175.63
175.67
175.72
175.73
175.75
175.85
175.94
175.94
176.0
4
176.06
176.07
M1
176.1
5
Tree Top 176.16
176.16
176.22
Tree Top 176.28
176.34
176.35
176.35
176.35
176.36
TR
OU
GH
TR
OU
GH
176.60
176.62
176.66
176.76
176.81
176.82
176.85
M2
176.96
Tree Top 176.97
Barb
wire Wire
mes
h Height=1.0m
177.03
Barb
wire Wire
mes
h Height=1.0m
177.09
177.1
0
177.12
177.16
177.19
177.22
177.27
177.29
177.32
177.35
177.37
177.42
177.44
177.46
177.47
Tree Top 177.47
177.47
177.54
177.56
177.60
Post & Rail Height=1m
177.64
177.65
177.67
177.67
177.69
177.72
Trac
k177.76
Tree Top 177.78
177.80
177.81
177.88
177.89
177.90
Tree Top 177.92Tree Top 177.95
177.95
178.02
Ditch
178.02
178.03
178.03
Barb
wire & M
esh Height=1m
178.06
178.08
178.10
178.14
178.19
178.26
178.29
Post & Rail Height=1.05m
178.39
178.40
Tree Top 178.41
178.54
Tree Top 178.56
178.58
178.61
Tree Top 178.64
Tree Top 178.68
178.89
Tree Top 178.91
178.94
178.94
178.98
179.03
179.06
179.14
179.24
179.29
179.31
179.32
Tree Top 179.34
179.39
Barbw
ire & Mesh H
eight=1.1m
179.43
179.43
179.45
Tree Top 179.46
179.48
179.60
179.60
179.60
179.63
179.63
Tree Top 179.73
179.73
179.76
179.77
179.80
179.81
179.87
179.89
179.93
179.96
180.01
180.09
180.16
180.28
180.29
180.35
180.36
Tree Top 180.37
180.39
Ditch180.50
180.76
181.07
Tree Top 181.11
181.21
Tree Top 181.22
181.23
181.24
Tree Top 181.25
181.27
181.29
Tree Top 181.30
181.33
181.39
181.42
181.44
181.45
181.54
181.56
181.57
181.58
181.59
181.61
Ditch
Tree Top 200.99
181.69
181.70
181.71
181.71
181.78
181.86
181.88
181.92
181.93
182.07
182.11
Tree Top 182.16
182.17
182.18
Tree Top 182.48
182.49
182.55
182.66
182.66
182.75
Tree Top 182.77
Tree C
anopy
Tree Top 182.93
182.93
182.95
183.10
183.14
183.31
183.38
183.39
183.50
183.50
183.60
183.71
183.76
183.79
183.80
183.83
183.85
183.88
183.89
183.97
183.98
184.01
184.07
184.10
184.11
184.35
184.38
184.40
184.46
184.46
Tree Top 184.55
184.58
Pasture
184.60
184.60
184.64
184.70
184.76
184.83
184.85
184.88
184.95
184.98
185.00
185.05
185.11
185.16
185.22
Tree Canopy
185.34
185.35
185.39
185.47
185.49
185.57
185.57
185.59
185.63
185.66
185.67
185.77
Tree Top 185.90
185.91
185.93
185.93
Tree Top 186.07
186.08
186.15
186.18
186.24
186.30
186.34
186.49
Tree Top 186.53
186.60
Ditch
186.76
186.76
186.84
186.88
186.89
186.92
186.99
187.05
187.10
187.19
Ditch
187.27
187.44
187.52
187.55
187.60
187.62
187.66
187.79
187.84
187.87
188.01
188.06
188.14
188.16
Tree Top 188.17
188.17
Tree Canopy
Tree Top 188.19
188.22
188.28
Tree Top 188.30
188.31
188.32
188.34
188.39
188.54
188.58
188.65
188.66
Tree Top 188.67
Pasture
188.71
188.71
188.76
188.80
188.83
188.85
188.85
Tree Top 188.97
189.01
189.03
189.12
189.23
Tree Top 189.24
189.27
189.39
189.48
189.49
189.52
189.52
189.75
189.77
189.79
189.80
189.82
189.86
189.88
189.89
189.94
189.96
190.02
190.03
190.15
190.16
190.28
190.35
190.37
190.45
190.48
Pasture190.48
190.52
190.54
Barbwire & Mesh Height=0.9m
190.56
190.66
190.78
Tree Top 190.90
190.91
Tree Top 191.04
191.08
191.12
191.17
191.27
191.29
Tree Top 191.32
191.34
191.36
Tree Top 191.48
191.52
Tree Top 191.57
191.57
191.58
191.59
191.68
191.70
191.72
Ditch
191.79
191.85
191.86
191.93
191.93
191.95
191.96
191.97
192.09
Tree C
anopy
192.17
192.17
192.17
192.19
192.20
192.21
192.22
192.25
192.28
192.31
192.35
192.36
192.46
192.51
192.54
192.57
192.64
192.69
192.72
192.74
192.83
Tree Top 192.88
192.89
192.93
192.94
193.25
193.35
193.38
193.40
193.41
193.46
193.48
193.48
193.48
193.56
193.67
193.72
193.74
193.77
Electric F
ence
193.89
Tree Top 193.93
193.93
194.00
194.01
194.02
194.06
Tree Top 194.17
194.19
Butt
Water
194.64
194.26
194.30
194.49
194.53
Barbw
ire & Mesh H
eight=1m 194.61
Barbw
ire & Mesh H
eight=1m
194.67
194.71
194.76
194.77
194.79
194.93
195.06
195.07
195.13
IL=195.26
195.30
195.42
195.43
195.45
195.46
195.47
195.49
195.53
195.56
195.83
195.88
195.88
195.9
6
Hedge top195.97
196.03
196.06
196.16
196.31
196.35
196.36
196.44
196.45
196.47
196.52
196.55
Tree Top 196.63
196.66
196.68
196.69
196.71
196.71
196.84
196.8
4
196.85
196.92
Tree Canopy
197.0
3
Ditch
197.10
Ditch
Ditch
Ditc
h
Tree Canopy
197.1
8
197.49
197.34
197.36
197.40
197.45
197.71
197.72
197.75
197.81
Tree
Can
opy
197.91
197.9
3
197.93
197.97
197.99
198.01
Hedge top198.02
198.04
198.04
198.09
198.15
198.26
198.26
198.26
198.30
198.31
198.37
198.3
8
198.46
198.50
198.59
198.6
4
198.68
198.69
198.69
198.71
198.74
Tree Top 218.12
198.78
198.84
Tre
e C
anopy
198.93
Electric Fence
198.97
198.99
199.06
199.19
199.2
3
199.25
Tree
Can
opy
199.43
199.45
Ditch
Tree Canopy
199.5
2
199.59
199.63
199.65
Tree C
anopy
199.77
199.80
199.80
199.81
199.82
199.88
199.88
199.89
199.9
1
Ditch
199.94
199.97
200.15
Ditch
Ditch
200.08
200.17
200.17
200.18
200.19
200.24
200.24
200.25
200.28
Tree Top 200.40
200.45
200.46
200.50
Tree Top 200.50
200.51
200.5
2
200.55
200.61
200.67
200.68
200.70
Tree
Can
opy
200.79
200.81
200.87
200.87
Pond
200.91
200.92
200.94
200.94
201.01
201.07
201.08
201.08
201.13
201.15
201.15
201.15
201.18
201.31
201.31
201.33
201.33
201.34
201.37
Barbwire & Wire
mes
h Ht=1.1m
201.40
Barbwire & Wire
mes
h Ht=1.1m
201.44
Barbwire & Mes
h Height=1.1m
201.50
201.71
201.72
201.73
201.74
201.80
201.85
201.93
202.32
202.45
202.50
202.50
202.50
Tree Top 202.55
202.56
202.71
202.76
Tree Top 203.60
203.87
Tree Top 204.42
Tree Top 204.66
Tree Top 204.71
Tree Top 204.97
Tree Top 205.13
Tree Top 205.25
Tree Top 205.27
Tree Top 206.80
Tree Top 207.20
Tree Top 207.33
Tree Top 207.52
Tree Top 207.59
Tree Top 207.96
Tree Top 208.68
Tree Top 208.77
Tree Top 208.96
Tree Top 209.14
Tree Top 209.16
Tree Top 209.27
Tree Top 209.29
Tree Top 209.55
Tree Top 209.68
Tree Top 209.86
Tree Top 210.08
Tree Top 210.12
Tree Top 210.15
Tree Top 210.68
Tree Top 210.82
Tree Top 211.80
Tree Top 213.91
Tree Top 214.52
Tree Top 214.55
Tree Top 214.68
Tree Top 214.86
Tree Top 214.90
Tree Top 214.91
Tree Top 215.06
Tree Top 215.73
Tree Top 215.81
Tree Top 216.33
Tree Top 216.42
Tree Top 216.77
Tree Top 216.85
Tree Top 217.13
Tree Top 217.72
Tree Top 217.75
Tree Top 218.33
Tree Top 218.81
Tree Top 219.21
Tree Top 219.24
Tree Top 219.38
Tree Top 220.05
Tree Top 220.40
Tree Top 220.40
Tree Top 220.50
Tree Top 220.56
Tree Top 221.03
Tree Top 221.09
Tree Top 221.97Tree Top 221.97
Tree Top 223.12
Tree Top 223.20
Tree Top 227.63
Tree Top 228.86
Tree Top 232.30
IL=176.77
Long Grass
Long Grass
Long Grass
Long Grass
Long Grass
Long Grass
N
Scale Factor = 1
Projection OSTN02 and OSGM02
Grid and Levels to National Grid
CLIENT JOB TITLE
Sheet 2
NP44 7AS
Cwmbran
Henllys
Cwrt Henllys Farm
Topographical Survey
EC1N 2HT
London
33 Holborn
7th Floor
Lightsource Renewable Energy Ltd
REVISIONS
SCALE
DATE SURVEYED BY
CHECKED BY
DRAWING No.
A0 Sheet @ 1 to 500
15732-200-01T Sheet 2
MC PAH
MCJuly 2015
BL
BS
BT
DP
EP
EB
FH
FP
GY
GV
Ht
Bollard
Bus Stop
Telecom Cover
Down Pipe
Electricity Pole
Fire Hydrant
Fence Post
Gulley
Gas Valve
Height
Kerb Inlet
Electricity Box
LC
MK
MW
RP
RS
SA
TL
TP
VP
WM
WO
Lamp Column
Marker Post
Reflector Post
Road Sign
Soak Away
Traffic Light
Telegraph Pole
Vent Pipe
Water Meter
Wash Out
Monitoring Well
UTS Unable to Survey
AV Air Valve
CATV Cable TV Cover
EY Electricity Cover
Gate PostGP
FFL Finished Floor Level
THL Threshold Level
CL Cover Level
CP Catch Pit
CR Cable Riser
Depth in Meters
Invert Level
MH Manhole
MK Marker Post
MS Mile Stone
OHC Overhead Cable
PB Post Box
BB Belisha Beacon
PostPO
RE Rodding EyeER Earth RodRNP Road Name Plate
SC Stop Cock (Water)
SD Sump Depth
Silt Silt Level
Sign PostSP
SV Stop Valve (Water)
WL Water Level
NPV No Pipe Visible
EOT End of Trace
UTL Unable to Lift
UTT Unable to Trace
TS Traffic Sign
BH Bore Hole
BT CAB Telecom Cabinet
EIC Electrical Inspection Cover
ECAB Electrical Cabinet
Bin Litter Bin
MK-BT Marker Post (Telecoms)
MK-FH Marker Post (Fire Hydrant)
MK-GV Marker Post (Gas Valve)
MK-SV Marker Post (Stop Valve)
MK-WM Marker Post (Water Meter)
MYIC Mercury Telecoms IC
SL Soffitt Level
TVIC Cable TV Inspection Cover
TL CAB Traffic Light Cabinet
Ground Penetrating RadarGPR
D
IL
KI
LEGEND
Brunel Surveys LtdUNIT 59, SHRIVENHAM HUNDRED BUSINESS PARK
WATCHFIELD, SWINDON, WILTSHIRE, SN6 8TZ
TEL : (01793) 784700 FAX : (01793)784664
WEB : www.brunelsurveys.com
Email:[email protected]
Underground Utility Surveyors
Photomontage, 3D Visualisations and
Land and Measured Building Surveyors
DRAWN BY
Sheet 1
Sheet 2
191900N
191950N
192000N
192050N
192100N
192150N
192200N
Appendix C
Rainfall Runoff Volume Calculations
Existing Site Impermeable Area (m2) 0
Permeable Area (m2) 143,180
Timestep Design Rainfall Design Rainfall Vol Net rainfall Nett Rainfall Vol
hrs mm m3 mm m^3
0 0.999 0.00 0.243 34.79
0.4 1.459 0.00 0.359 51.40
0.8 2.125 0.00 0.532 76.17
1.2 3.095 0.00 0.794 113.68
1.6 4.477 0.00 1.188 170.10
2 6.434 0.00 1.788 256.01
2.4 9.156 0.00 2.71 388.02
2.8 11.577 0.00 3.704 530.34
3.2 9.156 0.00 3.149 450.87
3.6 6.434 0.00 2.329 333.47
4 4.477 0.00 1.677 240.11
4.4 3.095 0.00 1.186 169.81
4.8 2.125 0.00 0.827 118.41
5.2 1.459 0.00 0.574 82.19
5.6 0.999 0.00 0.396 56.70
6 0.00 0.00 0.00 0.00
Total Site Runoff Volume
Runoff Volume (m3) 0.0 3072.1 3072 m3
Site - Post Development Impermeable Area (m2) 622
Permeable Area (m2) 142,558
Timestep Design Rainfall Design Rainfall Vol Net rainfall Nett Rainfall Vol
hrs mm m3 mm m^3
0 0.999 0.62 0.243 34.64
0.4 1.459 0.91 0.359 51.18
0.8 2.125 1.32 0.532 75.84
1.2 3.095 1.93 0.794 113.19
1.6 4.477 2.78 1.188 169.36
2 6.434 4.00 1.788 254.89
2.4 9.156 5.70 2.71 386.33
2.8 11.577 7.20 3.704 528.03
3.2 9.156 5.70 3.149 448.92
3.6 6.434 4.00 2.329 332.02
4 4.477 2.78 1.677 239.07
4.4 3.095 1.93 1.186 169.07
4.8 2.125 1.32 0.827 117.90
5.2 1.459 0.91 0.574 81.83
5.6 0.999 0.62 0.396 56.45
6 0.00 0.00 0.00 0.00
Total Site Runoff Volume
Runoff Volume (m3) 41.7 3058.7 3100 m3
Increase in effective rainfall runoff volume
28 m3
(= Post Development Runoff Volume - Exisitng Site Runoff Volume)
