Complete Appellant submission

Renfrewshire Council · 30 January 2024
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APPELLANT’S
SUBMISSIONS

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1 
ICDP Architects, Moorpark House, 11 Orton Place, Glasgow G51 2HF 
APPEAL STATEMENT Application 22/0706/PP 
Project: Erection of Two (2) Chalets    Report prepared by: WJF
Address: East Fulwood Farm House, Houston Rd, Inchinnan, Renfrew PA4 9LX
Job No: GW 22 723      
Applicant:   Ms Lyndsey Martin
Date:     9 October 2023 
1.0 INTRODUCTION 
1.1 The application reference 22/0706/PP was registered on 5 December 2022 seeking
Planning Permission to erect two Chalets at East Fulwood Farm. 
1.2 The application was refused under delegated powers on 11 July 2023. 
2.0 REASONS FOR REFUSAL 
2.1 Reason 1. citing the following reason for the decision:  
The proposed development is at a location susceptible to flooding. It does not
therefore align with the precautionary and avoidance principles advocated by the
sustainable flood risk management framework and is contrary to Policy 22 of
National Planning Framework 4, Policy 13 of the Adopted Renfrewshire Local
Development Plan and the associated New Development Supplementary
Guidance on Delivering the Infrastructure Strategy (Flooding and Drainage). 
3.0 RESPONSE 
3.1 Policy 22 of NPF 4: Policy 22 Flood Risk and Water Management is addressed and
relevant as the proposed development will be resilient to current and future flood risk. As per
Policy 22a) i and iv, the development proposal of two Chalets within a flood risk area can be
supported if they are for the redevelopment of an existing site for an equal or less vulnerable
use and where proposals demonstrate that the long term safety and resilience can be secured
in accordance with relevant SEPA advice (Part a. iii and iv respectively).

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2
3.2 The application site is brownfield in nature and the proposed use of the site is of equal
vulnerability as the previous use was residential in nature being conjoined to the Farmhouse
for purposes associated with the residence.
3.3 For development proposals that meet criteria Part iv, where flood risk is managed at
the site rather than avoided there is also a requirement for the first occupied/utilised floor to be
above the flood risk level and have an additional allowance for the freeboard and in the event
of a flood to avoid the creation of an island development and that safe access/egress can be
achieved.
3.4 The Applicant has commissioned a detailed Flood Risk Assessment by Messrs
Terrenus Land & Water (included with this Application) to examine in detail the potential risks
associated with this small scale development. For new developments the acceptable risk of
flooding must take account of the various factors including risk to human health and the direct
and indirect financial losses relating to flooding. Under existing conditions, the risks from
flooding at the site are determined as follows:
1. The majority of the site is at Little or No Risk of flooding from an isolated extreme
costal flooding event. The northwest edge adjacent to the Lin Burn is at Low to
Medium Risk.
2. The site is at Little or No Risk of surface water flooding.
3. The site is at Little or No Risk of flooding as a result of a failure in the local
drainage network.
4. The site is at Little or No Risk of isolated groundwater rise.
5. The site entrance and along the southeast boundary are considered to be Medium
to High Risk of fluvial flooding. The majority of the site is at Low to Medium Risk
of fluvial flooding from the Lin Burn.
3.5 While dry pedestrian and vehicular access and egress is compromised by the
functional floodplain, the anticipated depths are minimal and will not be sufficient to prevent
access to the site. Furthermore, this inundation on the access is limited to only the vicinity of
the site, with the remainder of the access road being free from flooding throughout all
considered storm events.
3.6 LDP Policy 13 – Flooding and Drainage: Policy 13 promotes avoidance as the first
principle of sustainable flood risk management. New development requires to avoid areas
susceptible to flooding.
3.7 It is accepted that the site is susceptible to flood. The calculated potential flood level
however is minimal and the proposed design avoids the risk of flood to residents and structures
by lifting the finished floor from +450mmOD to +600mmOD an increase of 150mm.
4.0 PROPOSED DEVELOPMENT AND FLOOD RESILIANCE MEASURES
4.1 The proposed redevelopment has been applied for under the land use classification
Most Vulnerable which is the same classification as the existing Farmhouse. To comply with
this classification the following flood mitigation and flood resilience measures will be
incorporated to ensure there is minimal impact upon the flood storage, conveyance and risk to
the proposed re-development and site neighbours.

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4.2 The Applicant proposes the following design measures:
1. No land raising within the functional floodplain within the site.
2. A final Ground Floor Level of 6.75mOD which will provide a 300mm freeboard on
the 1 in 200-year plus climate change event peak water level and a 350mm
freeboard on the 1 in 1000-year event for the development.
3. Use of Flood Resistant construction methods and materials for the new Chalets.
4. Locating electrical equipment outwith estimated peak water surface elevations at
a minimum of 6.87mOD, allowing for a 600mm freeboard.
5. Registration with SEPA Floodline for flooding alerts.
6. Installation of a bespoke flood monitoring alarm system to initiate a site flood
evacuation plan.
7. Provision of a raised stilted walkway (as submitted Site Plan L(--)01 Rev A) to
permit residents to exit the Chalets keeping their feet dry to the higher ground level
at the Farmhouse.
5.0 PHYSICAL WORKS ASSOCIATED WITH THE EXISTING WATERCOURSE
5.1 In relation to flood risk, the Water Environment (Controlled Activities)
(Scotland) Regulations 2005 (CAR) may be affected by the development site. The Applicant
acknowledges that no earthworks shall be carried out within the banks of the Lin Burn without
prior consultation with SEPA and the application of the relevant licensing guidance in relation
to CAR regulations.
5.2 Construction works on site will likely require sediment control for surface water
runoff to ensure watercourses are not impacted by increased sediment load as a result of
construction activities. A pollution prevention plan or surface water management plan will be
agreed with SEPA.
6.0 CONCLUSION
6.1 Scottish Planning Policy notes that new developments should be free from
significant flood risk from any source and that such developments should not:
1. Materially increase the probability of flooding elsewhere.
2. Add to the area of land which requires protection by flood prevention measures.
3. Affect the ability of the functional flood plain to attenuate the effects of flooding by
storing flood water.
4. Interfere detrimentally with the flow of water in the floodplain,
5. Compromise options for future river management.
6.2 It has been established that parts of the site lie within the functional
floodplain. Given that the access road to the site allows pedestrian and vehicle access during
the design storm event, development of areas within the functional floodplain in line with the
measures of mitigation as outlined above, can be considered to be in the spirit of the broad
principles of Scottish Planning Policy.
6.3 The Applicant proposed to make a mandatory registration with the SEPA
Floodline and will install a flood monitoring/ alarm system in conjunction with a site evacuation
plan and operation and maintenance policy highlighting flood risk responsibilities and

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mitigation measures. All accommodation is located above the maximum flood level and an
elevated walkway to ground outwith the calculated flood level is also incorporated together
with construction which is flood resistant. 
6.4 As the Application complies with the broad principles of the Development
Plan and is supported by relevant material considerations, and with there being no material
considerations to indicate otherwise, the appeal should be allowed and the Application
approved.

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International House,
Hamilton International Park,
Stanley Boulevard,
Hamilton,
G72 0BN 
www.terrenus.co.uk 
EAST FULWOOD FARM, INCHINNAN
FLOOD RISK ASSESSMENT REPORT
FOR
LYNDSEY MARTIN
Report No. 1698-207 Version: Original
Author: DA Issue Date: 5 April 2022

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EAST FULWOOD FARM, INCHINNAN
FLOOD RISK ASSESSMENT REPORT
FOR
LYNDSEY MARTIN 
SITE SUMMARY INFORMATION 
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Name of Site: East Fulwood Farm, Inchinnan
Ordnance Survey Grid Reference: NS 45515 67875
Site Address: East Fulwood Farm, Houston Road, Inchinnan,
PA4 9LX
Local Authority: Renfrewshire Council
Land Use (Existing): Vacant Hardstanding
On site buildings: No
Proposed Site Use: Holiday Dwelling
Area (m2); 425m2 
Local Development Plan (LDP); LDP 2 2021- ENV1 Greenbelt 
Type of Investigation: Level 3 Flood Risk Assessment

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EAST FULWOOD FARM, INCHINNAN
FLOOD RISK ASSESSMENT REPORT
FOR
LYNDSEY MARTIN 
TABLE OF CONTENTS 
SECTION          PAGE 
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1 INTRODUCTION .................................................................................................................................... 1
1.1 BACKGROUND ............................................................................................................................ 1
1.2 OBJECTIVES OF INVESTIGATION ........................................................................................ 1
1.3 SCOPE OF STUDY ....................................................................................................................... 1
1.4 PROPOSED SITE END-USE ....................................................................................................... 1
1.5 LIMITATIONS OF REPORT ...................................................................................................... 1
2 SITE DETAILS ......................................................................................................................................... 2
2.1 DATA SOURCES .......................................................................................................................... 2
2.2 SITE LOCATION & DESCRIPTION ......................................................................................... 2
2.2.1 Ground Truthing ............................................................................................................................. 2
2.3 SITE HISTORY ............................................................................................................................. 3
2.4 SITE NEIGHBOURS .................................................................................................................... 3
2.5 HYDROLOGY AND DRAINAGE............................................................................................... 3
2.5.1 SEPA Flood Map ............................................................................................................................ 3
2.5.2 Scottish Water Assets ..................................................................................................................... 4
2.6 GEOLOGICAL SETTING ........................................................................................................... 4
2.7 FLOOD DEFENCE WORKS ....................................................................................................... 4
3 FLOOD RISK ASSESSMENT ................................................................................................................ 5
3.1 GENERAL ...................................................................................................................................... 5
3.2 COASTAL FLOOD RISK ............................................................................................................ 5
3.2.1 Coastal Flood Boundary Conditions for the UK (2018) ................................................................. 5
3.2.2 Assessed Risk of Inundation from the Sea ..................................................................................... 6
3.3 JOINT PROBABILITY ................................................................................................................ 6
3.4 SURFACE WATER ....................................................................................................................... 7
3.5 LOCAL DRAINAGE ..................................................................................................................... 7
3.6 GROUNDWATER RISE .............................................................................................................. 8
3.7 FLUVIAL FLOOD RISK .............................................................................................................. 8
3.7.1 General ............................................................................................................................................ 8
3.7.2 Model Domain ................................................................................................................................ 8
3.7.3 Digital Terrain Development .......................................................................................................... 8

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EAST FULWOOD FARM, INCHINNAN
FLOOD RISK ASSESSMENT REPORT
FOR
LYNDSEY MARTIN
TABLE OF CONTENTS
SECTION PAGE
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3.7.4 Contributing Catchments ................................................................................................................ 9
3.7.5 Inflow Boundary Condition ............................................................................................................ 9
3.7.6 Climate Change Allowance .......................................................................................................... 10
3.7.7 Downstream Model Boundary ...................................................................................................... 10
3.7.8 Roughness Coefficient .................................................................................................................. 11
3.7.9 Structures ...................................................................................................................................... 12
3.7.10 Computational Mesh ................................................................................................................... 12
3.7.11 Computational Time Step ........................................................................................................... 13
3.7.12 Mass Balance Errors ................................................................................................................... 13
3.7.13 Equation Set and Default Parameters ......................................................................................... 13
3.7.14 Projection .................................................................................................................................... 13
3.7.15 Sensitivity Analysis .................................................................................................................... 14
3.7.16 Velocity ....................................................................................................................................... 15
3.7.17 Froude Number ........................................................................................................................... 15
3.7.18 Courant Number ......................................................................................................................... 15
3.7.19 Model Results under Existing Conditions .................................................................................. 16
3.7.20 Blockage Analysis ...................................................................................................................... 16
4 DISCUSSION AND RECOMMENDATIONS ..................................................................................... 17
4.1 GENERAL .................................................................................................................................... 17
4.2 DEVELOPMENT AND POSSIBLE FLOOD RESILIENCE MEASURES .......................... 17
4.3 PHYSICAL WORKS ASSOCIATED WITH THE EXISTING WATERCOURSE ............. 17
4.4 EFFECTS ON SITE NEIGHBOURS ........................................................................................ 18
4.5 OVERALL FLOOD RISK ASSESSMENT CONCLUSION .................................................. 18

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EAST FULWOOD FARM, INCHINNAN
FLOOD RISK ASSESSMENT REPORT
FOR
LYNDSEY MARTIN 
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Figures
Figure 1 – Site Location Plan
Figure 2A – Terrenus Spot Heights Survey 
Figure 2B – Terrenus Spot Heights Survey 
Figure 3 – Survey Comparison Points
Figure 4 – Flow Accumulation Pathways
Figure 5 – Catchment Analysis
Figure 6 – Lin Burn Fluvial Hydrographs
Figure 7 – Black Cart Water Fluvial Hydrographs
Figure 8 – River Gryffe Fluvial Hydrographs
Figure 9 – Tidal Hydrographs
Figure 10 – 1 in 200-Year Fluvial Storm Event Inundation Extent 
Figure 11 – 1 in 200-Year plus Climate Change Allowance Fluvial Storm Event
Inundation Extent
Figure 12 – 1 in 500-Year Fluvial Storm Event Inundation Extent
Figure 13 – 1 in 1000-Year Fluvial Storm Event Inundation Extent
Figure 14 – 1 in 1000-Year plus Climate Change Allowance Fluvial Storm Event
Inundation Extent
Figure 15 – 1 in 1000-Year Tidal Storm Event Inundation Extent
Figure 16 – 1 in 1000-Year plus Climate Change Allowance Tidal Storm Event
Inundation Extent
Figure 17 – 1 in 1000-Year Fluvial Storm Event Maximum Water Velocity
Figure 18 – 1 in 1000-Year Fluvial Storm Event Froude Sensitivity Analysis
Figure 19 – 1 in 1000-Year Fluvial Storm Event Courant Sensitivity Analysis
Figure 20 – 1 in 200-Year Fluvial Storm Event Inundation Extent – Minor
Blockage Analysis
Figure 21 – 1 in 200-Year Fluvial Storm Event Inundation Extent – Major
Blockage Analysis 
Tables
Table 1 – Simple Desktop Joint Probability Analysis
Table 2 – Peak Flow Methodology Analysis
Table 3 – Peak Flow Estimation Summary 
Photographic Plates 
Catchment Descriptors 
HEC-RAS Computation Reports 
SEPA FRA Checklist

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EAST FULWOOD FARM, INCHINNAN
FLOOD RISK ASSESSMENT REPORT
FOR
LYNDSEY MARTIN
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1 INTRODUCTION
1.1 BACKGROUND
The development of a holiday dwelling on the grounds of East Fulwood Farm, Inchinnan is currently
under consideration by the Client, Lyndsey Martin.
The Lin Burn flows in close proximity to the northwest boundary and joins the River Gryffe some
430m south-southeast of site. As part of the development process Terrenus Land & Water Ltd was
commissioned by Messrs Mabbett & Associates Ltd, on behalf of the Client, to carry out a Level 3
flood risk assessment of the site.
1.2 OBJECTIVES OF INVESTIGATION
The principal aim of the investigation is to define the functional floodplain in the local area and to
assess the risk of flooding to the proposed development.
1.3 SCOPE OF STUDY
The following tasks were undertaken during the course of this investigation:
• Site walkover inspection;
• Acquisition of site topographic spot height data;
• Collation of data;
• Assessment of data;
• Joint probability analysis;
• 2D Hydraulic Modelling using HEC-RAS modelling software; and
• Production of an Interpretative Report.
1.4 PROPOSED SITE END-USE
It is understood that the proposed development of the site will involve the construction of a holiday
cabin. The site location and extent is shown on Figure 1, which is included in the Appendix.
It is noted that the proposed development increases the SEPA Land Use Vulnerability Classification1
as per table 1 in the guidance document, holiday dwellings are classified as Most Vulnerable and thus
the 1 in 1000-year storm event constitutes the design storm event.
1.5 LIMITATIONS OF REPORT
Terrenus Land & Water Ltd has prepared this report for the sole use of the Client, in accordance with
generally accepted consulting practice and for the intended purpose as stated in the related contract
agreement. No other warranty, expressed or implied, is made as to the professional advice included in
this report. Should any third party wish to use or rely upon the contents of the report, written approval
must be sought from Terrenus Land & Water Ltd; a charge may be levied against such approval.
To the best of our knowledge, information contained in this report is accurate at the date of issue.
There may be conditions pertaining at the site not disclosed by the study, which might have a bearing
on the recommendations provided if such conditions were known. We have, however, used our
professional judgement in attempting to limit this during the assessment.
It is important therefore that these implications be clearly recognised when the findings of this study
are being interpreted. In addition, this should be borne in mind if this report is used without further
confirmatory investigation after a significant delay.
1 https://www.sepa.org.uk/media/143416/land-use-vulnerability-guidance.pdf

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East Fulwood Farm, Inchinnan
Flood Risk Assessment Report
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Lyndsey Martin
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Page 2 of 18
2 SITE DETAILS
2.1 DATA SOURCES
The following data sources were consulted during the course of the Flood Risk Assessment:
• Client-supplied data including site location;
• 0.5m Phase 5 DTM LiDAR data set, obtained from the Scottish Remote Sensing
Portal;
• Site walkover inspection and additional topographic surveying;
• Flood Estimation Handbook – Web Service (FEH13);
• Publicly available online historic maps; and
• Available additional information.
2.2 SITE LOCATION & DESCRIPTION
The site is located within a rural area of Renfrewshire, near Inchinnan, situated 1km west of
Inchinnan Business Park, and is centred on National Grid Reference NS 45515 67875. As shown on
Figure 1, which is contained within the Appendix.
The site covers and area of around 425m2 and has an approximately rectangular shaped boundary,
which lies between the southern bank of the Lin Burn and the existing farm steading of East Fulwood
Farm. The boundary is marked by palisade fencing on the northwest and southwest edges and the
wall of the farm steading building to the southeast. The northwest boundary is open to the site access
road.
An understanding for the local topography was provided by project commissioned topographic spot
height survey undertaken by Terrenus Land & Water Ltd during the site walkover inspection on the
7 March 2022. The location of the spot heights acquired by Terrenus are shown on Figures 2A & 2B,
contained within the Appendix.
The site is generally flat-lying with a very slight slope southeast to northwest, from a high of
6.0m OD to 5.77m OD. The Lin Burn channel bed lies at around 2.9mOD.
2.2.1 Ground Truthing
The LiDAR dataset was ‘truthed’ against the spot height survey data at key locations within the site
and surrounding area. Table A, below, provides a sample of the spot height survey points against the
LiDAR data. The average deviation between the LiDAR and survey data is 17mm, with the greatest
differential being 30mm which is reasonable in this instance. The locations of the survey points
chosen for comparison are shown on Figure 3. The LiDAR data was found to be a reasonable and
accurate representation of the local topography.
Survey Point Surveyed Levels LiDAR Data Levels Deviation
1 6.13 6.12 +0.01
2 6.0 6.01 -0.01
3 6.48 6.48 0
4 6.58 6.61 -0.03
5 5.46 5.49 -0.03
6 4.99 5.01 -0.02
Average Deviation 0.017
Maximum Deviation 0.03
Table A: Ground Truthing
The survey comparison found that LiDAR levels within the Lin Burn channel were typically around
600mm higher than actual surveyed levels. This effect is due to the water and vegetation within the
channel providing a surface within the LiDAR dataset.

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East Fulwood Farm, Inchinnan
Flood Risk Assessment Report
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Lyndsey Martin
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Page 3 of 18
2.3 SITE HISTORY
The site and East Fulwood Farm as a whole is shown on the First Edition Ordnance Survey maps
dated 1863. The site and adjacent farm steading are shown to be relatively unchanged since the
earliest record. The farm steading is noted to have been changed, likely the historic structure was
demolished and replaced with the steading that is now present. The warehouse of the landscaping
company to the southeast of site is absent and due to its modern construction, was likely erected in
the 2010’s.
Little change is recorded in the wider area, with the exception of the relatively recent M8 to the west
and the expansion of the industrial estate and Inchinnan to the east.
2.4 SITE NEIGHBOURS
Immediately adjacent to the southeastern site boundary is the farm steading of East Fulwood Farm,
with the courtyard beyond. Further southeast is the parking area and warehouse of a local landscaping
firm.
Immediately south of the site is the garden of East Fulwood Farm, with small paddocks beyond.
The Lin Burn flows north to south along the northwest and western site boundary, with agricultural
fields beyond.
Immediately north of the site is the road bridge over the Lin Burn which connects to the fields north
of the site.
2.5 HYDROLOGY AND DRAINAGE
The Lin Burn is the closest watercourse to the site. This watercourse is fed by the fields north of site
and has a catchment of 5.03km2. The burn is culverted at numerous locations along its course and
generally lies within a steep-banked trapezoidal channel. Approximately 440m south-southeast of the
site, the Lin Burn comes to confluence with the River Gryffe.
The River Gryffe, which is a tributary of the Black Cart Water and the River Clyde further
downstream flows from west to east originating from Loch Thorn and the Gryffe Reservoirs 20km
upstream of the site.
During the site walkover, the channel bed of the River Gryffe was noted to be generally flat with
gravel and cobbles present. The banks of the watercourse are earthen and well-defined.
The Black Cart Water is fed by the hills of Clyde Muirshiel some 14km southwest of the site. It is
additionally fed by runoff from the fields and by tributaries along its course towards the River Clyde.
2.5.1 SEPA Flood Map
The Scottish Environment Protection Agency (SEPA) has produced ‘Flood Maps’ for the local area.
These maps are enhanced and show potential flooding from coastal, rivers (fluvial) and surface water
(pluvial) sources. In addition, the maps provide a breakdown of flood likelihood in broad agreement
with the Scottish Planning Policy Risk Framework.
A review of the maps indicate that the site is within the Medium to Low Likelihood of fluvial flood
risk, with a High Likelihood of fluvial flooding immediately adjacent to the northwestern boundary.
There is no likelihood of surface water flood risk at site, according to the SEPA flood maps.
There is no likelihood of coastal flood risk at site, however, a high likelihood of coastal flood risk is
present along the course of the Lin Burn in the immediate vicinity of site, and along the River Gryffe
and the Black Cart Water in the wider vicinity. This indicates that there is coastal/tidal influence on
the water levels at site.
There is no likelihood of flood risk from any source on the access road or Houston Road as it heads
east.

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SEPA makes the following statement about the Flood Map:
“The river flood map was developed using a nationally consistent approach to producing flood
hazard information, such as depth of water and speed of flow arising from river flooding. It is
based on a two-dimensional flood modelling method applied across Scotland to all catchments
greater than 3km2. The river flood map includes hydraulic structures and defences such as
bridges, culverts and flood storage areas where appropriate information was available.
and
The surface water flood map combines information on rainfall and sewer model outputs. It
incorporates data from a national surface water study, a regional surface water study with
increased resolution in selected areas and a Scottish Water sewer flooding assessment.”
The flood map should be treated with caution and SEPA makes the following general comment:
“The flood maps are designed to provide a community level assessment of flooding and its
impacts. They model flooding at a national scale. As with any approach of this scale, there are
limitations and assumptions made to enable modelling and a consistent approach to be applied
across Scotland. Limitations arise from the data used to create the maps, the modelling
techniques applied and the ability to incorporate datasets from local studies into a national
approach.”
Additional background details of the SEPA flood map can be found on the SEPA website:
http://www.sepa.org.uk/flooding/flood_maps.aspx
2.5.2 Scottish Water Assets
From a review of Scottish Water asset plans there are no known Scottish Water drainage assets in the
vicinity of the site with the nearest assets being along Barnsford Road A726 1km east of site.
A trunk water supply main runs adjacent to the Lin Burn upstream of site and along the access road.
A visible washout is located upstream of the bridge adjacent to the site’s northern boundary.
An abandoned pipe is present along the northern edge of Houston Road south of site, evidence of
which is visible upstream of the Houston Road bridge over the Lin Burn.
The Scottish Water assets plans are included in the Appendix.
2.6 GEOLOGICAL SETTING
The following summary of the solid and superficial geology of the site is based on a review of the
British Geological Survey (BGS) Geology of Britain Viewer2.
The underlying superficial deposits are recorded to comprise gravel, sand and silt of Devensian age
raised tidal flat deposits.
The bedrock at site is recorded to comprise a mix of the Lower Limestone Formation and Limestone
Coal Formation.
2.7 FLOOD DEFENCE WORKS
There are no known flood defence works within the vicinity of the site.
2 http://mapapps.bgs.ac.uk/geologyofbritain/home.html

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3 FLOOD RISK ASSESSMENT
3.1 GENERAL
Flooding occurs when the amount of water arriving on land exceeds the capacity of the land to
discharge that water (by infiltration, overland flow, groundwater rise or a failed drainage system). It
can occur on any level or near-level areas of land but the main concern in inland areas is with land
adjacent to watercourses (fluvial flooding) and the possibility of overland flow (surface water
flooding). 
3.2 COASTAL FLOOD RISK
3.2.1 Coastal Flood Boundary Conditions for the UK (2018)
A review of the Coastal Flood Boundary Conditions for the UK: Update 2018 was undertaken, and
the September 2020 dataset was utilised following download from data.gov.uk3. The data was
downloaded and used under Open Government License V3.0.
The nearest node to the site lies on the River Gryffe, within the Clyde Estuary section of the dataset.
The node is situated at the confluence of the Lin Burn and the River Gryffe, some 430m south of the
site. The Coastal Design Sea Level – Coastal Flood Boundary (CDSL-CFB) Extreme Sea Level
Estuary layer was examined and data for the node at Chainage 1806_51 was adopted. The dataset
includes the extreme sea level values for still water sea levels and are based on 2017/18 topographic
data for boundary outlines.
Confidence levels provide allowances for uncertainty. The 2.5% and 97.5% confidence levels
associated with an extreme sea level estimate are the values such that, in the interval between these
values, there is a 95% probability of observing the true extreme sea level. This interval is often
referred to as the 95% confidence interval and is commonly used to quantify the uncertainty
associated with parameter estimates of a statistical model. The 2.5% and 97.5% confidence levels are
provided and referred to as 'C1_' and 'C2_' respectively.
Table B below summarises the dataset entry for the node at Chainage 1806_51:
Is study
area
within
estuary
areas?
Adopted
Chainage
point
Allowance for
Uncertainty - c1
(2.5%) Confidence
Level (mO.D.)
Coastal Design
Sea Levels -
Coastal Flood
Boundary Extreme
Sea Levels
Estuary (mO.D.)
Allowance for
Uncertainty - c2
(97.5%) Confidence
Level (mO.D.) 
Application of Climate
Change Allowance -
(using Table 3 from
SEPA Guidance for
Clyde River Basin) (m)
Yes 1806_51 c1_T1 3.68 T1 3.73 c2_T1 3.78   0.85  
c1_T2 3.85 T2 3.91 c2_T2 3.97      
c1_T5 4.06 T5 4.14 c2_T5 4.23   
c1_T10 4.18 T10 4.29 c2_T10 4.40    
c1_T20 4.30 T20 4.44 c2_T20 4.60    
c1_T25 4.34 T25 4.49 c2_T25 4.67    
c1_T50 4.44 T50 4.63 c2_T50 4.85    
c1_T75 4.49 T75 4.70 c2_T75 4.98  T1000 plus Climate
Change Allowance
(mO.D.):  
c1_T100 4.50 T100 4.73 c2_T100 5.03 
c1_T150 4.52 T150 4.77 c2_T150 5.12 
c1_T200 4.54 T200 4.81 c2_T200 5.19  5.86  
c1_T250 4.54 T250 4.83 c2_T250 5.24   
c1_T300 4.56 T300 4.86 c2_T300 5.28    
c1_T500 4.58 T500 4.92 c2_T500 5.40    
c1_T1000 4.61 T1000 5.01 c2_T1000 5.59    
c1_T10000 4.68 T10000 5.03 c2_T10000 6.47  
Table B: Extreme Sea Levels and Climate Change Allowance 
3 https://data.gov.uk/dataset/73834283-7dc4-488a-9583-a94.8320072d9a9d/coastal-design-sea-levels-coastal-
flood-boundary-extreme-sea-levels-20184

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As can be seen from Table B, the T1000 Tide extreme sea level within the Clyde Estuary has been
predicted at 5.01mOD. A review of the project commissioned spot height data indicates that the
majority of the site is at or above 5.66m OD. This puts the site entirely outwith the 1 in 1000-year
tidal event floodplain.
Application of the SEPA Climate Change Allowances for Flood Risk Assessment in Land Use
Planning4 guidance puts the site within the Clyde River Basin Region, with a corresponding sea level
rise allowance of 0.85m, up to year 2100. It should be noted that SEPA recommend that an additional
allowance of 0.15m per decade after the year 2100 be applied where the design life of a development
is known to extend beyond that date. Assuming a design life up to year 2100 the peak extreme sea
level estuary level for the site would be 5.86mOD. The inclusion of climate change to the 1 in 1000-
year tidal level would impact the northwestern edge of the site, however, depths are less than or equal
to 200mm.
3.2.2 Assessed Risk of Inundation from the Sea
The site is situated inland of the Firth of Clyde and is protected by the canalised Black Cart Water
and heavily modified River Clyde.
The distance from the estuary mouth with the Firth of Clyde will limit tidal, wave and wind fetch
from generating significant waves.
The northwestern edge of the site is considered to be at Low to Medium Risk of coastal flooding
from an isolated extreme sea level coastal event.
The remainder of the site is at Little or No Risk of flooding from coastal sources.
Hydraulic modelling of the Tidal conditions at the site are discussed in full in Section 3.7 below.
3.3 JOINT PROBABILITY
The analysis was undertaken using the DEFRA / Environment Agency (EA) Flood and Coastal
Defence R&D Programme Technical Reports FD2308/TR1, FD2308/TR2 and FD2308/TR3. These
reports look at Joint Probability: Dependence Mapping and Best Practice, Use of Joint Probability
Methods in Flood Management and Joint probability: Dependence between extreme sea surge, river
flow and precipitation. Together these technical reports provide a robust methodology and approach
to the assessment of Joint Probability and form the current guide to best practice for this assessment.
The first variable was established as the peak flow rate of the River Gryffe for a range of eleven (11)
return periods: 1 in 1-year, 1 in 2-year, 1-in 5-year 1 in 10-year, 1 in 20-year, 1 in 50-year, 1 in 75-
year, 1 in 100-year, 1 in 200-year, 1 in 500-year and 1 in 1000-year. The peak flow estimations for
each return period were carried out using the Revitalised Flood Estimation Handbook, Version 2.3
(ReFH2.3), which calculates the peak flow estimation from the Flood Estimation Handbook Web
Service (FEH13) Catchment Descriptors.
The second variable was established as the peak still extreme sea level for the same return periods.
The data was taken from the Coastal Design Sea Level – Coastal Flood Boundary Dataset (April 19)
and applied to the DEFRA/EA Skew Surge Joint Probability Method. The results of the assessment
are shown in Table B in Section 3.2.1 above. As the tidal sequence is applied for the peak sea level
assessment, the number of records / years for the joint probability assessment was set at 707.
The Correlation Factor (CF value) for the 1 in 1000-year event used the 1 in 500-year values from
Table 3.6 of the DEFRA/EA R&D Technical Report FD2308/TR1 (pg38). This is the most severe
storm event considered under the current guidance and extrapolation was not considered a feasible
approach. Thus, the correlations will be approximate.
4
https://sepaweb.maps.arcgis.com/apps/webappviewer/index.html?id=a01f82dbc66145f4a4b558d7b840f51a&ex
tent=-2086266.4068%2C6926044.231%2C1044594.2717%2C9056497.0833%2C102100

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The level of dependence for the relationship between river flow and surge was taken from Figure 2 in
the DEFRA/EA R&D Technical Report FD2308/TR2 (pg22). The nearest river station to the site was
taken as Station 84011 – Gryffe at Craigend (NGR NS414663). The River Gryffe at Craigend is
noted to be Well Correlated in the level of dependence between river flow and surge. This level of
dependence has been adopted for the simple desktop joint probability assessment. The CF value for
the 1 in 1000-year event was calculated at CF = 182.
The results of the simple desk study joint probability analysis are shown in Table 1, included in the
Appendix.
A review of Table 1 shows that the 1 in 1000-year peak flow estimation of the River Gryffe
(317.21m3/s) has a joint exceedance return period peak sea level of 0.69mOD, which is less than a
peak tide of a 1 in 1-year tidal event. This means that a 1 in 1000-year fluvial storm event (Q1000) is
not likely to occur during any tidal storm event. Conversely, a 1 in 1000-year tidal storm event
(T1000) is likely to coincide with a 1 in 1-year fluvial event (Q1) of 50m3/s.
Under less severe fluvial storm events such as the Q200 and Q500, the corresponding tidal event
remains less than 1 in 1-year and vice versa.
3.4 SURFACE WATER
Topographic maps, LiDAR data and project commissioned spot height survey data were interrogated
to determine general overland flow pathways for the site and the surrounding area. The general
indicative overland flow pathways are shown on Figure 4, which is included in the Appendix.
Within the site, overland flow pathways stem from the access road and flow west across the site. The
local landform will prevent ponding within the site.
Overland flow from the adjacent fields will be prevented from entering site by the raised road and the
Lin Burn.
It is therefore considered that the site is at Little or No Risk of surface water flooding.
It is understood that any proposed development will comply with Renfrewshire Council requirements
for Sustainable Drainage Systems (SuDS), if applicable.
3.5 LOCAL DRAINAGE
No drainage infrastructure currently serves the site. Standard roof drainage was noted to be in place
along the southeast boundary, servicing the farm steading. No road drainage at site or along the
access road was evidenced during the site walkover inspection.
In the event of the adjacent roof drainage becoming blocked, some nuisance water may wash onto
site. The gentle slope of the landform and the lack of ponding-supporting topography will mean that
any such water will wash across the site as shallow overland flow and fall into the Lin Burn before
being carried away from site.
Standard field drainage is expected to be in place in the neighbouring fields. This drainage will
discharge into the Lin Burn and not directly impact the site. Any upwelling from damaged field
drains will be prevented from entering site by the raised road deck and the presence of the Lin Burn.
A failure in road drainage along Houston Road leading to upwelling at the gullies may result in
shallow overland flow onto the southernmost extent of the farm access road. This flow will wash
across the access road due to the lack of kerbing and infiltrate into the soils of the fields.
Due to the site’s sloping topography towards the watercourse and the lack of significant drainage
infrastructure within the site or surrounding area, the site is assessed to be at Little or No Risk of
flooding from a failure in drainage systems.

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3.6 GROUNDWATER RISE
Given the presence of historic Made Ground and the underlying superficial deposits of alluvium,
there is potential for perched groundwater beneath the site.
The groundwater in close proximity to the Lin Burn is likely to be in hydraulic continuity with the
watercourses, but the extent will be extremely limited due to the narrow profile of the burn.
Site commissioned survey spot height data records the bed of the Lin Burn to be at around 3.0mOD,
with the lowest site level around 5.66mOD. This gives at least 2.66m between the site level and the
bed of the burn.
Local superficial groundwater will be impacted by the Lin Burn, however the site is considered to be
at Little or No Risk of isolated Groundwater rise. Groundwater may be present at shallow depth and
encountered during any further excavation.
3.7 FLUVIAL FLOOD RISK
3.7.1 General
Fluvial flood risk in the vicinity of the site arises primarily from the interaction of the Lin Burn and
the River Gryffe.
The hydrological analysis uses modified Flood Estimation Handbook Web Service data (FEH13)
together with the Hydrologic Engineering Centre’s River Analysis System (HEC-RAS), developed by
the U.S. Army Corps of Engineers (USACE). HEC-RAS Version 6.1. HEC-RAS provides
appropriate 2D hydraulic flood modelling capabilities for the determination of flood routing, overland
flow conveyance and flood storage.
Whilst the current HEC-RAS model (6.1) does allow for infiltration, no infiltration losses were
applied to this model.
3.7.2 Model Domain
The two-dimensional (2D) flow area for the model covers an area of 3.72km2. The model domain was
established to be inclusive of all floodplain and potential overland flow pathways that could impact
the site and site neighbours from the three watercourses. The extent of the model domain is shown on
Figure A.
Figure A – Model domain
3.7.3 Digital Terrain Development
A digital terrain was developed in HEC-RAS using the following terrain data:
• Scottish Remote Sensing Portal 0.5m Phase 5 LiDAR DTM data set (NS46 NW & NE tiles);
• TLW GS08 Leica Geosystem Survey Staff and Net Rover Spot Heights – March 2022.

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The existing terrain is a composite terrain surface generated from the RAS Mapper functionality
within HEC-RAS 6.1. The LiDAR forms the basis of the topographic data and the channel profiles
were refined by supplementing the LiDAR data with the project commissioned spot height survey
data. This allowed for a more accurate representation of the channels. Figure B shows an extract of
the final existing terrain used for the hydraulic modelling.
Figure B – Existing Terrain Model
3.7.4 Contributing Catchments
Catchment descriptors for the three watercourses were obtained from the Flood Estimation Handbook
Web Service (FEH13).
Catchments for the River Gryffe and Black Cart Water could not be generated in the vicinity of site
owing to them being considered tidal catchments at this location under the FEH methodology. Thus,
in order to capture suitable fluvial catchments for these watercourses, the closest upstream catchments
were extracted and extended to encompass their catchment area up to the vicinity of the site. Due to
the areal alterations being greater than 10% of each catchment’s area, alterations to other catchment
descriptors was necessary. The revised catchment descriptors for the Gryffe and Black Cart are
included in the Appendix.
The River Gryffe originates from Loch Thorn and the Gryffe Reservoirs some 20km upstream of the
site. The revised River Gryffe catchment is 144.54km2 in extent.
The Black Cart Water is initially fed from the hills and moors of Clyde Muirshiel Regional Park as
the runoff flows into the Lochwinnoch lochs. The Black Cart is additionally fed by runoff from the
fields and burns along its course towards its confluence with the River Clyde. The revised Black Cart
Water catchment is 139.97km2 in extent.
From review of topographic data, the representation of the Lin Burn catchment was considered
accurate and its catchment descriptors were applied without any change. The Lin Burn catchment is
5.04km2 in extent.
The revised catchment extents are shown on Figure 5, which is included in the Appendix.
3.7.5 Inflow Boundary Condition
Gauging station data for the Craigend Gauge was reviewed for the River Gryffe. The National River
Flow Archive5 indicates the gauge to lie some 4.4km west of the site at NGR NS 41476 66362. A
review of the gauging station records a maximum observed flow of 142.03m3/s since its earliest
records in 1963.
There is also a SEPA gauging station on the Black Cart Water at Milliken Park (NGR NS 41122,
62025), upstream of the site. This station records a maximum observed flow of 110m3/s since its
earliest records in 1963.
5 https://nrfa.ceh.ac.uk/

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In each instance, the gauging stations are located significantly upstream of site and the highest
recorded flows of each are lower than the estimations calculated using the methodologies described
below.
Catchment descriptors from the Flood Estimation Handbook web service (FEH13) were used to
calculate the peak flow estimation for the contributing catchments and are included in the Appendix.
The peak flow estimation was calculated using the following methodologies:
• FEH Statistical;
• Revitalised Flood Hydrograph, Version 2.3 (ReFH2.3); and
• FEH Rainfall Runoff.
The results of the flow estimations found that the FEH Rainfall Runoff was the most conservative of
the methodologies.
Table 2, in the Appendix provides a summary of the design storm event peak flow estimations under
various methodologies. Table 3 provides a suite of peak flow estimations under a variety of storm
events using the FEH Rainfall Runoff methodology.
The inflow boundary conditions were applied as hydrographs with energy gradients calculated from
the terrain.
3.7.6 Climate Change Allowance
A review of the SEPA Climate Change Allowances for Flood Risk Assessment in Land Use Planning
web map6 shows that the site lies within the Clyde River Basin Region and in the West Rainfall
Uplift Region.
As per the SEPA guidance, the applicable Climate Change Allowance (CCA) for the Lin Burn is an
increase of 55% on Peak Rainfall Intensity due to the catchment size being less than 30km2.
As per the SEPA guidance, the applicable Climate Change Allowance (CCA) for the River Gryffe
and Black Cart Water is an increase of 44% on Peak River Flow due to the catchment sizes being
greater than 50km2.
Table B, below, lists the corresponding peak flow estimates for the watercourse.
1 in 1000-year
flow
1 in 1000-year plus Climate Change
Allowance (CCA)
Lin Burn 14.55 24.78
River Gryffe 317.21 456.78
Black Cart Water 374.55 539.35
Table B – Peak inflow rates
The 1 in 1000-year and 1 in 1000-year plus climate change allowance inflow hydrographs are shown
on Figures 6 to 8, which are contained within the Appendix.
3.7.7 Downstream Model Boundary
The downstream model boundary condition is set to a time/stage relationship representing a typical
tidal sequence within the Clyde Estuary. The was included in the model as a stage hydrograph to
represent the influence of the tide on this point of the watercourses.
6https://sepaweb.maps.arcgis.com/apps/webappviewer/index.html?id=a01f82dbc66145f4a4b558d7b840f51a&e
xtent=-2086266.4068%2C6926044.231%2C1044594.2717%2C9056497.0833%2C102100

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The MIKE21 Tidal Prediction mode, by DHI, was used to generate a typical 3-day tidal sequence as
close to the site as possible. The tidal sequence was then modified to provide coincident peaks
between the fluvial discharge from the River Gryffe and peak tide. This is a conservative estimation,
as the likelihood of coincident peaks is low.
The tidal sequence was then adapted to match the peak water levels from the Coastal Flood Boundary
Dataset, with a baseline fluvial scenario peak water level of 3.73m OD, which equates to a 1 in 1-year
tidal storm event.
Finally, the tidal sequences were adjusted using the Simplified Harmonic Method for the storm surge
profile at the nearest Admiralty Port, Rothesay Dock, Clydebank.
Additional tidal sequence levels corresponding to the 1 in 1-year plus Climate Change Allowance and
the 1 in 1000-year extreme sea level with and without Climate Change Allowance, were also
assessed.
The downstream boundary was applied at the downstream extent of the modelled domain across the
River Gryffe. The modelling software calculates separate water surface elevations per cell face along
the boundary condition line.
The downstream boundary condition was applied as a stage hydrograph and these stage hydrographs
are shown on Figure 9, included in the Appendix.
3.7.8 Roughness Coefficient
A global Manning’s n roughness coefficient value of 0.03n was applied to the whole domain. This
value was derived from the mid-range for short-grassed pasture, which makes up the majority of the
model domain. Where notable land use changes occur a separate Manning’s n map layer was added to
the model to reflect changes in land use. The Manning’s n map layer overwrites the global Manning’s
n value and applied a new value corresponding to the terrain as can be seen below on Figure C.
Figure C – Existing Manning’s n Layer Extract
The Manning’s roughness coefficients n values assigned to the polygons are summarised below in
Table C:
Colour Land Use
Classification Manning’s n Value
Cyan Channel 0.03
Green Woodland/brush 0.07
Magenta Road 0.013
Red Building 0.1
Table C – Existing Manning’s n values for hydraulic modelling
All Manning’s n values are based on a review of aerial imagery, the site walkover inspection and are
aligned to those described in Manning’s n for Channels (Chow, 1959).

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Manning’s n values of 0.07n were applied to areas of more dense vegetation and brush coverings, or
areas with mature stands of trees with branches outwith the flood zone. Road surfaces were attributed
a roughness value of 0.013n for asphalt. The channel was set with a roughness value of 0.03n for
clean, straight channels.
Where the existing buildings are present within the floodplain, a Manning’s n roughness value of 0.1n
was applied to the footprint of the building. This simulates the slowing of flow through vents, doors
and other openings into the building. No terrain modifications were made to represent buildings
within the model.
3.7.9 Structures
There are two structures present within the model domain, these being the bridge immediately
upstream of the site and the Houston Road bridge downstream.
Each of these structures has been included in the model as a 1D (one-dimensional) feature, with a
break line assigned perpendicular to flow to represent the overtopping weir. Each structure is set to a
weir representing the overtopping level of the road, and an associated culvert barrel. The details of
each structure are described below.
The upstream bridge has a 1.7m wide, 1.9m tall arched culvert orifice, with a weir set at the road deck
level.
Figure D – 1D HEC-RAS Structure – Upstream Bridge
The downstream bridge has a 1.9m wide, 1.9m tall arched culvert orifice, with a weir set at the road
deck level.
Figure E – 1D HEC-RAS Structure – Downstream Bridge
3.7.10 Computational Mesh
A 5m-by-5m computational mesh was assigned to the whole model domain. The profiles of the Lin
Burn, River Gryffe and Black Cart Water were aligned through the use of central break lines and

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lateral bank break lines. The break lines served to orientate the grid cells perpendicular to flow and to
refine the mesh resolution along the channels.
Each channel is represented by a minimum of eight cells at any cross-sectional location, however this
is not necessary for accurate representation of the channels, due to HEC-RAS recognising sub-grid
topography/bathymetry and creating more than 1 result per cell.
Figure F below shows an extract of the geometry file including the computational grid around the
site.
Figure F – Extract of 2D Geometry with Computational Mesh
3.7.11 Computational Time Step
A fixed 0.5 second time step was applied as the computational time step. The results of the modelled
outputs were reviewed for Courant Number violations and velocity spikes which could indicate
instability. No instabilities were found within the modelled outputs and the model time step was
assessed to be appropriate. The model simulation was set to run for 24 hours of the predicted peak
flow estimation hydrographs. The simulation time allows for all the peaks, both fluvial and tidal, to
pass and for receding water levels to be observed throughout the domain.
Comparison with a finer timestep of 0.2 seconds found that water levels and other key outputs
remained consistent, indicating that the adopted timestep of 0.5 seconds is considered suitable.
3.7.12 Mass Balance Errors
HEC-RAS tracks the cumulative mass balance error throughout the simulation window. Mass balance
errors and water surface elevation convergence errors were checked to ensure model stability and that
imbalances remained below reasonable thresholds, confirming compliance with Courant Number
criteria.
The maximum recorded Mass balance error is 0.0145% for the percentage error, well within
tolerances. Computational Reports recording Mass Balance Errors for the modelled scenarios are
contained within the Appendix.
3.7.13 Equation Set and Default Parameters
Unsteady plan files were run using the Shallow Water Equations with Eulerian-Lagrangian approach
to solving for advection, the SWE-ELM (original/faster) equation set. The SWE-ELM
(original/faster) equation set was chosen for the model in order to account for inertial terms resulting
from the multidirectional flow paths inherent in the modelled area.
All other parameters were set to default values.
3.7.14 Projection
All geospatial input and output data are projected using the OSGB 1936 British National Grid.

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3.7.15 Sensitivity Analysis
To assess the model sensitivity to various parameters, a series of sensitivity analyses was undertaken
with respect to the flow, roughness coefficient and downstream boundary conditions.
Analysis of the watercourse was undertaken with a variety of flow rates (1 in 200-year, 1 in 500-year,
1 in 1000-year and 1 in 1000-year plus Climate Change Allowance events). Profile lines were drawn
at the locations shown on Figure G and maximum water surface elevations recorded and shown on
Table D.
Figure F – Extract of 2D Geometry with Computational Mesh
Profile
Line
Water Levels at site during fluvial storm events (m OD)
Q200 Q200+CCA Q500 Q1000 Q1000+CCA
1 6.03 6.34 6.18 6.28 6.43
2 6.03 6.33 6.18 6.28 6.43
3 5.06 6.15 5.87 6.05 6.24
4 4.97 6.18 6.05 6.12 6.30
5 4.92 5.46 5.08 5.32 5.84
Table D – Flow Sensitivity Analysis
The variations in peak water level are in line with expectations. The 1 in 200-year flow is largely
contained within the channel banks however, under more severe storm conditions, out of bank flows
occur from higher water levels, leading to overland flow and inundation at site. The model is,
therefore, not considered to be unduly sensitive to changes in peak flow. Figures 10 through 14
provide the extent of inundation during the considered storm events.
Analysis of the watercourse was undertaken with a +/-20% variation on the Manning’s n values. The
variation in maximum water surface elevation on the baseline scenario from the sensitivity analysis is
up to 50mm at site. Such variation has negligible impact on the inundation extents at site. The model
is, therefore, not considered to be unduly sensitive to changes in Manning’s n value.
Further analysis of the watercourse was undertaken with variations on the downstream boundary
condition. Analysis of the tidal impact was undertaken with a variety of tidal storm events (1 in 200-
year with and without Climate Change Allowance, 1 in 500-year, 1 in 1000-year and 1 in 1000-year
with and without Climate Change Allowance). Profile lines were drawn at the locations shown on
Figure G and maximum water surface elevations recorded and shown on Table E:

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Profile
Line
Water Levels at site during fluvial storm events (m OD)
Q200 Q200+CCA Q500 Q1000 Q1000+CCA
1 4.90 5.72 5.0 5.08 5.89
2 4.90 5.72 5.0 5.08 5.89
3 4.90 5.74 5.0 5.08 5.93
4 4.90 5.74 5.0 5.08 5.93
5 4.90 5.74 5.0 5.08 5.93
Table E – Tide Sensitivity Analysis
The variations in peak water level are in line with expectations. The tidal storm events are largely
contained within the channel banks in the vicinity of site however, under the 1 in 1000-year plus
Climate Change Allowance event, out of bank flows occur from higher water levels, leading to
inundation at site. The model is, therefore, not considered to be unduly sensitive to changes in peak
flow. The results of the tidal analysis in Section 3.2 are corroborated by hydraulic modelling.
Figures 15 and 16 provide the extent of inundation during the 1 in 1000-year tidal storm and the 1 in
1000-year tidal storm plus climate change scenario, respectively.
3.7.16 Velocity
Figure 17, contained within the Appendix records the maximum water velocities recorded throughout
the model domain during the 1 in 1000-year fluvial storm event. As can be seen, maximum velocities
throughout the domain are typically less than 1m/s. Highs of up to 5.26m/s are recorded in the
vicinity of the large Barnsford Road and M8 structures, owing to the increase in velocity from
passing through a constriction.
3.7.17 Froude Number
Figure 18, contained within the Appendix records the maximum Froude Number values throughout
the model domain. Froude Numbers in excess of 1 are generally indicative of super-critical flow and
have erosive potential, Froude Numbers of 1, or less, are generally indicative of sub-critical flow and
have low erosive potential.
As can be seen from Figure 18, throughout the model the Froude Numbers are generally less than 1,
indicating sub-critical flow and low erosive potential, as well as indicating a stable model. Froude
Numbers in excess of 1 typically occur along the banks of the Black Cart water downstream of its
confluence with the River Gryffe which may lead to erosion of the banks which is supported by
observations made during the site walkover.
3.7.18 Courant Number
The maximum Courant Number values for the model were taken at time 6 hours and 30 minutes into
the modelled run time; this is equivalent to the maximum inundation at the site. Courant Numbers are
generally at or below 0.4 throughout the site and the immediate surrounding area. Courant Numbers
less than 1 indicate stable model performance and sufficient timestep refinement to avoid any Courant
Number violations in the hydraulic calculations. Courant numbers at or near 1 are associated with
main channel flows, structures and areas of refined computational mesh grid sizes, such as within the
channel of the Lin Burn.
A review of the Courant numbers confirms that the model is within acceptable tolerances, with all
Courant values less than 3.0 as outlined in the HEC-RAS technical manual. This confirms that the
timestep chosen is appropriate.
The maximum Courant Number values are shown on Figure 19, in the Appendix.

Page 31

East Fulwood Farm, Inchinnan
Flood Risk Assessment Report
for
Lyndsey Martin
Y:\1600-1699\1698 - Mabbett & Associates Ltd\1698-207 - East Fulwood Farm, Inchinnan FRA\5. Deliverables\1698-207 East Fulwood Farm, Inchinnan FRA.doc
Page 16 of 18
3.7.19 Model Results under Existing Conditions
As with all fluvial flood models, uncertainties remain that affect the relationship between flow rate
and water level. The analysis must, therefore, be regarded as approximate whilst using the best
available data at the time of reporting.
The 1 in 200-Year fluvial storm event constitutes the functional floodplain and should be avoided,
whilst the 1 in 1000-year fluvial storm event constitutes the design storm event and influences design
criteria.
The bridge immediately upstream of site constrains the peak flow in the channel and causes backing
up of water, resulting in overtopping of the road and overland flow onto site through the site entrance.
Flow entering site will wash across before falling back into the Lin Burn.
The peak water level during the 1 in 200-year fluvial event is recorded to be 6.03m OD at the site
entrance, falling to 5.93m OD near the southern site corner.
The peak water level during the 1 in 1000-year fluvial event is recorded to be 6.27m OD at the site
entrance, falling to 5.96m OD along the southwest boundary.
Elements of the site are at Medium to High Risk of fluvial flooding and lie within the functional
floodplain, however, the expected depths are at or less than 70mm. The majority of the site is at Low
to Medium Risk of fluvial flooding with depths up to 150mm within the site and up to 290mm at the
site entrance.
Figures 10 and 13 show the fluvial inundation at site during the 1 in 200-year and 1 in 1000-year
events, respectively.
3.7.20 Blockage Analysis
Under existing conditions, there are no sources that could significantly block the orifices of the two
bridges. Thus, 15% and 30% blockages were considered reasonable for the sensitivity analysis if
somewhat conservative. This was applied by reducing the span of the culverts, thus imposing a
constriction to flow throughout the full hydrograph.
The blockage scenarios were considered for the both the 1 in 200-year and 1 in 1000-year fluvial
storm events.
Under the 15% minor blockage scenario, the 1 in 200-year water levels at site rise by 20mm. Under
the 30% major blockage scenario, the 1 in 200-year water levels rise by 170mm. The extent of
inundation is not significantly increased under the minor blockage scenario. However, under the
major blockage scenario, the vast majority of the site is inundated due to the overland flow path from
the field to the northeast of site. Figures 20 and 21 provide the extent of inundation during the 1 in
200-year fluvial storm during the minor and major blockage scenarios, respectively.
Under the 15% minor blockage scenario, the 1 in 1000-year water levels at site rise by 50mm. Under
the 30% major blockage scenario, the 1 in 1000-year water levels rise marginally by 90mm. The
extent of inundation is not significantly increased under either of the scenarios.

Page 32

East Fulwood Farm, Inchinnan
Flood Risk Assessment Report
for
Lyndsey Martin
Y:\1600-1699\1698 - Mabbett & Associates Ltd\1698-207 - East Fulwood Farm, Inchinnan FRA\5. Deliverables\1698-207 East Fulwood Farm, Inchinnan FRA.doc
Page 17 of 18
4 DISCUSSION AND RECOMMENDATIONS
4.1 GENERAL
For new developments the acceptable risk of flooding should take into account various factors
including risk to human health and the direct and indirect financial losses relating to flooding.
Under existing conditions, the risks from flooding at the site are defined as follows:
• The majority of the site is at Little or No Risk of flooding from an isolated extreme coastal
flooding event. The northwest edge, adjacent to the Lin Burn, is at Low to Medium Risk.
• The site is at Little or No Risk of surface water flooding.
• The site is at Little or No Risk of flooding as a result of a failure in the local drainage
network.
• The site is at Little or No Risk of isolated groundwater rise.
• The site entrance and along the southeast boundary are considered to be at Medium to High
Risk of fluvial flooding. The majority of the site is at Low to Medium Risk of fluvial
flooding from the Lin Burn.
While dry pedestrian and vehicular access and egress is compromised by functional floodplain, the
anticipated depths will not be sufficient to prevent access to the site. Furthermore, this inundation on
the access is limited to only the vicinity of site, with the remainder of the access road being free from
flooding throughout all considered storm events.
4.2 DEVELOPMENT AND POSSIBLE FLOOD RESILIENCE MEASURES
The proposed redevelopment has been applied for under the land use classification 5, Most
Vulnerable. To comply with this application, the following flood mitigation and flood resilience
measures will be required to ensure there is minimal impact upon the flood storage, conveyance and
risk to the proposed re-development and site neighbours.
The following design measures are required:
• No land raising within the functional floodplain within the site;
• A Final Ground Floor Level of 6.57mOD is recommended (providing a 300mm freeboard on
the 1 in 200-year plus climate change event peak water level and a 350mm freeboard on the 1
in 1000-year event for the development).
• Use of Flood Resilient construction methods and materials for new building(s);
• Locating electrical equipment outwith estimated peak water surface elevations at a minimum
of 6.87m OD, allowing for 600mm freeboard;
• Mandatory registration with SEPA Floodline for flooding alerts;
• Installation of bespoke flood monitoring alarm system to initiate site flood evacuation plan.
4.3 PHYSICAL WORKS ASSOCIATED WITH THE EXISTING WATERCOURSE
In relation to flood risk, the Water Environment (Controlled Activities) (Scotland) Regulations 2005
(CAR) may be affected by the development of the site. No earthworks shall be carried out within the
banks of the Lin Burn without prior consultation with SEPA and the application of the relevant
licensing guidance in relation to CAR.
Any construction works will likely require sediment control for surface water runoff to ensure
watercourses are not impacted by increased sediment load as a result of construction activities. A
pollution prevention plan or surface water management plan for construction may also be required.
Early consultation with SEPA is recommended in relation to any proposed construction works to
ensure compliance.

Page 33

No embedded text on this page.

Page 34

EAST FULWOOD FARM, INCHINNAN
FLOOD RISK ASSESSMENT REPORT
FOR
LYNDSEY MARTIN 
APPENDICES

Page 35

EAST FULWOOD FARM, INCHINNAN
FLOOD RISK ASSESSMENT REPORT
FOR
LYNDSEY MARTIN 
FIGURES

Page 36

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
Site Location Plan
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
1
Site Location
Renfrewshire County Boundary
Atlas
Site Boundary
Google Satellite Hybrid

Page 37

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
Spot Heights Survey
Checked:
DA
Approved:
DA
Date:
17/03/22
Figure:
2A
Spot Heights
Site Boundary
Google Satellite Hybrid

Page 38

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
Spot Heights Survey
Checked:
DA
Approved:
DA
Date:
17/03/22
Figure:
2B
Site Boundary
Spot Heights
Google Satellite Hybrid

Page 39

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
Survey Comparison Points
Checked:
DA
Approved:
DA
Date:
17/03/22
Figure:
3
Site Boundary
Comparison Points
Google Satellite Hybrid

Page 40

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
Flow Accumulation Pathways
Checked:
DA
Approved:
DA
Date:
15/03/2022
Figure:
4
Site Boundary
Flow Accumulation
Google Satellite Hybrid

Page 41

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
Catchment Analysis
Checked:
DA
Approved:
DA
Date:
15/03/2022
Figure:
5
Site Location
Black Cart Catchment
Gryffe Catchment
Lin Burn Catchment
Google Satellite Hybrid

Page 42

Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawing Title:
Lin Burn Hydrographs
Drawn:
JS
Checked:
DA
Approved:
DA
Date:
29/03/2022 Figure:
6

Page 43

Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawing Title:
Black Cart Water
Hydrographs
Drawn:
JS
Checked:
DA
Approved:
DA
Date:
29/03/2022 Figure:
7

Page 44

Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawing Title:
River Gryffe Hydrographs
Drawn:
JS
Checked:
DA
Approved:
DA
Date:
29/03/2022 Figure:
8

Page 45

Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawing Title:
Tidal Stage Hydrographs
Drawn:
JS
Checked:
DA
Approved:
DA
Date:
29/03/2022 Figure:
9

Page 46

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 200-Year Fluvial Storm Event
Inundation Extent - Site Specific
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
10
Site Boundary
Q200 Depth (Max)
Google Satellite Hybrid

Page 47

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 200-Year plus Climate Change
Allowance Fluvial Storm Event
Inundation Extent - Site Specific
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
11
Site Boundary
Q200 +CCA Depth (Max)
Google Satellite Hybrid

Page 48

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 500-Year Fluvial Storm Event
Inundation Extent - Site Specific
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
12
Site Boundary
Q500 Depth (Max)
Google Satellite Hybrid

Page 49

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 1000-Year Fluvial Storm Event
Inundation Extent - Site Specific
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
13
Site Boundary
Q1000 T1 Depth (Max)
Google Satellite Hybrid

Page 50

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 1000-Year plus Climate Change
Allowance Fluvial Storm Event
Inundation Extent - Site Specific
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
14
Site Boundary
Q1000 T1 +CCA Depth (Max)
Google Satellite Hybrid

Page 51

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 200-Year plus Climate Change
Allowance Tidal Storm Event
Inundation Extent - Site Specific
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
15
Site Boundary
T200 +CCA Depth (Max)
Google Satellite Hybrid

Page 52

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 1000-Year plus Climate Change
Allowance Tidal Storm Event
Inundation Extent - Site Specific
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
16
Site Boundary
T1000 +CCA Depth (Max)
Google Satellite Hybrid

Page 53

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 1000-Year Fluvial Storm Event
Maximum Water Velocity
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
17
Site Boundary
Q1000 T1 Velocity (Max)
Google Satellite Hybrid
5.0m/s
0.001m/s

Page 54

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 1000-Year Fluvial Storm Event
Froude Sensitivity Analysis
Checked:
DA
Approved:
DA
Date:
15/03/2022
Figure:
18
Site Boundary
Q1000 T1 Froude (Max)
Google Satellite Hybrid

Page 55

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 1000-Year Fluvial Storm Event
Courant Sensitivity Analysis
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
19
Site Boundary
Courant V-L 18 30
Google Satellite Hybrid

Page 56

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 200-Year Fluvial Storm Event
Inundation Extent - Minor Blockage
Analysis
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
20
Site Boundary
Q200 Minor Block Depth (Max)
Google Satellite Hybrid

Page 57

Client:
Lyndsey Martin
Project:
East Fulwood Farm,
Inchinnan
Drawn:
JS
Terrenus Land & Water Ltd
Hamilton International Park
G72 0BN
www.terrenus.co.uk
Drawing Title:
1 in 200-Year Fluvial Storm Event
Inundation Extent - Major Blockage
Analysis
Checked:
DA
Approved:
DA
Date:
29/03/2022
Figure:
21
Site Boundary
Q200 Major Block Depth (Max)
Google Satellite Hybrid

Page 58

FILE
LOCATION: 
DATE
A3
PAPER SIZESCALEDRAWN
NAME:
STATUS:       SUITABILITY DESCRIPTION:
REVISION:       REVISION DESCRIPTION:
REV    DATE        DRW  REVISION  NOTES                 CHK  APP
REVISION HISTORY
PROJECT      ORIGINATOR           ZONE            LEVEL        TYPE     ROLE         NUMBER
Development at East Fulwood Farm
Lyndsey Martin
09/10/2023 1:200
ICDP- L(--)01
REV A
GW227
23
- 00 XX DR A- - - -
CF
CLIENT
PROJECT
Moorpark House, 11 Orton Place, Glasgow, G51 2HF  0141 445 3974
info@icdparchitects.com                         www.icdparchitects.com
F
F
5,500
5,500
3,000
EXISTING PROPERTY
EXISTING PROPERTY
EXISTING COURTYARD
TO B790 HOUSTON ROAD
LIN BURN
LIN BURN
EXISTING SEPTIC
TANK
EXISTING OIL/GAS
TANK
RAMP
RAMP
COLUMN
RAMP
RAMP
COLUMN
COLUMN
NEW
BIO-DISC
Floor Space
33
m 2
PLANNING APPLICATION
SITE PLAN
A RAISED WALKWAY ADDED BETWEEN BUILDINGS TO GARDEN AREA

Page 59

Chief Executive's Service
Renfrewshire House
Cotton Street, Paisley, PA1 1WB
//www.renfrewshire.gov.uk
My Ref: 
Contact: James Weir
Telephone: 07483 370666
Email: dc@renfrewshire.gov.uk
Date: 11 July 2023 
William  Findlater
ICDP Architects
Moorpark House
11 Orton Place
Glasgow
G51 2HF 
Proposal: Erection of two Chalets
Location: East Fulwood Farm House, Houston Road, Inchinnan, Renfrew, PA4 9LX, 
Application Type: Planning Permission-Full
Application No: 22/0706/PP 
Dear Sir/Madam, 
NOTIFICATION OF REFUSAL OF CONSENT 
The Council has decided to refuse your application, details of which are given above. I enclose
a Decision Notice which provides details of the reasons for refusal. I also enclose a copy of your
submitted plans duly endorsed. 
You have the right to appeal against this decision to the Local Review Body and notes on how
to appeal are attached. 
Yours faithfully,
Alasdair Morrison
Head of Economy and Development

Page 60

Page 1 of 3 
Chief Executive's Service
Renfrewshire House
Cotton Street, Paisley, PA1 1WB
//www.renfrewshire.gov.uk
REFUSE Consent subject to the reasons 
Ref.  22/0706/PP     
DECISION NOTICE 
Town and Country Planning (Scotland) Act 1997
Planning etc. (Scotland) Act 2006
Town and Country Planning (Development Management Procedure) (Scotland) Regulations 2013     
TO
Mrs Lyndsey Martin
East Fulwood Farm House
Houston Road
Inchinnan
Renfrew
PA4 9LX 
With reference to your application registered on 17 October 2022 for Planning Consent for the
following development:- 
PROPOSAL
Erection of two Chalets 
LOCATION
East Fulwood Farm House, Houston Road, Inchinnan, Renfrew, PA4 9LX 
DECISION
The Council in exercise of their powers under the above Acts and Orders, having considered
the above proposal, the plans endorsed as relating to it and the particulars given in the above
application hereby:- 
REFUSE Consent subject to the reasons listed on the reverse/paper apart. 
PLANS AND DRAWINGS
The plans and drawings relative to this refusal are those identified in the Schedule of
Plans/Drawings attached as a paper apart and forming part of this Decision Notice. 
Dated: 10 July 2023 
Signed ......................................................
Appointed Officer
on behalf of Renfrewshire Council

Page 61

Page 2 of 3 
Ref. 22/0706/PP 
REASON FOR REFUSAL 
PAPER APART 
TERMS AND CONDITIONS 
Reason for Decision 
1. The proposed development is at a location susceptible to flooding. It does not therefore
align with the precautionary and avoidance principles advocated by the sustainable flood
risk management framework and is contrary to Policy 22 of National Planning
Framework 4, Policy I3 of the Adopted Renfrewshire Local Development Plan and the
associated New Development Supplementary Guidance on Delivering the Infrastructure
Strategy (Flooding and Drainage).

Page 62

Page 3 of 3 
TOWN AND COUNTRY PLANNING (SCOTLAND) ACT 1997 
1. If the applicant is aggrieved by the decision to refuse permission for or approval required by a
condition in respect of the proposed development, or to grant permission or approval subject to
conditions, the applicant may require the planning authority to review the case under section
43A of the Town and Country Planning Act (Scotland) Act 1997 within three months beginning
with the date of this notice. The notice of review should be addressed to Head of Legal and
Democratic Services, Renfrewshire House, Cotton Street, Paisley PA1 1PR. 
2. If permission to develop land is refused or granted subject to conditions and the owner of the
land claims that the land has become incapable of reasonably beneficial use in its existing state
and cannot be rendered capable of reasonably beneficial use by the carrying out of any
development which has been or would be permitted, the owner of the land may serve on the
planning authority a purchase notice requiring the purchase of the owner of the land's interest in
the land in accordance with Part 5 of the Town and Country Planning (Scotland) Act 1997.

Page 63

Appendix 1
RENFREWSHIRE COUNCIL Application No: 22/0706/PP
CHIEF EXECUTIVE’S SERVICE
RECOMMENDATION OF PLANNING APPLICATION
Regd:5 December 2022
Applicant Agent
Mrs Lyndsey Martin
East Fulwood Farm House
Houston Road
Inchinnan
Renfrew
PA4 9LX
William Findlater
ICDP Architects
Moorpark House
11 Orton Place
Glasgow
G51 2HF
Nature of Proposals
Erection of two Chalets
Site
East Fulwood Farm House, Houston Road, Inchinnan, Renfrew, PA4 9LX
Description
This application seeks planning permission for the erection of two chalets at East Fulwood Farm.
East Fulwood Farm is located 1km to the west of Inchinnan Business Park, and is accessed via a
single-track road which connects with the B790 which is 250m to the south east.
The farm comprises of an L shaped single storey farmhouse, with an agricultural barn to the
southeast. The proposed chalets will be positioned on a vacant area of ground immediately to the
rear (northwest) of the farmhouse. This area is enclosed by a screen fence, with the Linn Burn
and associated trees and vegetation to the north and west.
The proposed development comprises of a one bedroom (approx. 40 sqm) and a two bedroom
(approx. 63 sqm) chalet. They are of matching mono pitched roof design and incorporate access
ramps and external seating areas. The exterior will be finished in Cedral lap cladding. There are
two parking spaces proposed for each chalet.
History
No previous applications.
Policy and Material Considerations
Legislation requires planning decisions to be made in accordance with the Development Plan
unless material considerations indicate otherwise. In this instance, the proposal must be assessed
against the following:
Development Plan
National Planning Framework 4
NPF4: Policy 8 - Green belts
NPF4: Policy 22 – Flood Risk and Water Management
NPF4: Policy 29 - Rural development

Page 64

NPF4: Policy 30 – Tourism
Renfrewshire Local Development Plan
LDP 2021: Policy ENV1 - Green Belt
LDP 2021: Policy ENV4 - The Water Environment
LDP 2021: Policy ENV2 - Natural Heritage
LDP 2021: Policy I3 - Flooding and Drainage
LDP 2021: Policy E4 - Tourism
Supplementary Guidance
Delivering the Environment Strategy
Delivering the Infrastructure Strategy
Delivering the Economic Strategy
Publicity
Neighbour notification has been undertaken in accordance with the requirements of the
regulations.
Objections/Representation
None received.
Consultations
Chief Executives Service (Roads Development) – No objection subject to conditions relating to
the provision of sight lines at the main access.
Communities & Housing Services (Environmental Protection Team) - No comments.
Glasgow Airport Safeguarding – No objection.
SEPA – Object in principle to the application as the development is expected to put people or
property at risk of flooding, which is contrary to National Planning Framework 4.
Informative to be added: No
Assessment
Policy 8 and ENV1 specify forms of development that are acceptable in the green belt in principle.
One of these is tourism related development.
Policy 30 and E4 refer to tourism related accommodation as being acceptable provided it
contributes to the local economy and is compatible with the surrounding environment. Policy 29
also supports development that contributes to the viability, sustainability and diversification of rural
communities.
Taking the above into consideration, it is accepted that the erection of two chalets at this location

Page 65

is acceptable in principle.
However, the site is at risk of flooding from the Lin Burn, specifically a 1 in 200 year event with an
allowance for climate change. Policy 22 promotes flood avoidance as a first principle. The erection
of the chalets within the flood plain would be contrary to this principle. It is noted that the
development does not constitute one of the four development types that are exempt and can be
supported within a flood risk area.
SEPA have issued an objection in principle to the development on the basis that it does not
comply with Policy 22 and the requirement to avoid floodplains within the 1 in 200 year event.
SEPA have advised that the FRA submitted with the application is based on appropriate
methodologies and represents an accurate estimation of flooding at the site. The FRA indicates
that the site would be inundated during the 1 in 200 year event, and is therefore contrary in
principle to Policy 22.
Policy I3 also promotes avoidance as the first principle of sustainable flood risk management. New
development requires to avoid areas susceptible to flooding. The development is contrary to policy
I3.
In view of the above assessment, the development is found to be contrary to policies 22 and I3
with respect to flood risk. SEPA have also objected in principle to the development. It is therefore
considered that the application should be refused.
A site visit has been undertaken on 23rd August 2021, and photographs relevant to the application
have been archived.
RECOMMENDATION
Refuse
Reason for Decision
1. The proposed development is at a location susceptible to flooding. It does not therefore align
with the precautionary and avoidance principles advocated by the sustainable flood risk
management framework and is contrary to Policy 22 of National Planning Framework 4, Policy I3
of the Adopted Renfrewshire Local Development Plan and the associated New Development
Supplementary Guidance on Delivering the Infrastructure Strategy (Flooding and Drainage).
Alasdair Morrison
Head of Economy and Development

Page 66

Applicant:   Mrs Lyndsey Martin  Ref. No: 22/0706/PP
Site:           East Fulwood Farm House
Houston Road
Inchinnan
Renfrew
PA4 9LX
Officer:    James Weir 
Documents
Document Document Attached
(Admin)

Document Attached
and Signed

Decision Letter  
Decision Notice  
Appendix 1 – Report of Handling    
Plans to be stamped
Drawing Number Drawing Title Checked
Paper/DMS
(Officer)

Stamped
DMS
(BS)

L(--)03 Elevations – One Bedroom Chalet  
L(--)02 Elevations – Two Bedroom Chalet  
/ Location Plan  
L(--)04 Site Elevations & Pictures  
L(--)01 Site Plan  
L(--)06 Existing Road Splay Photos  
L(--)05 Junction Splay  
Officers Initials: JW   Business Support Initials: ___DM____

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