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Water Environment

Glasgow City Council Dec 2011 North Lanarkshire Council Glasgow and Clyde Valley Green Network Partnership

Gartloch and Gartcosh Hydrological Study


Water Environment

Glasgow City Council Dec 2011 North Lanarkshire Council Glasgow and Clyde Valley Green Network Partnership

This page is left blank deliberately


Prepared by:

Barry O’Connor Stephanie Rebours-Smith Hazel Smith

Checked by:

Debbie Hay-Smith Principal Hydrologist

Approved by: Peter Robinson Regional Director

Gartloch and Gartcosh Flood Risk Assessment and Surface Water Management Plan Rev No

Comments

Draft Final Draft Final

Checked by DHS PMR PMR

Approved by PMR PMR PMR

Date 3/10/11 28/10/11 01/12/11

1 Tanfield, Edinburgh, EH3 5DA Telephone: 0131 301 8600 Website: http://www.aecom.com Job No 60186328

Reference M001.001

Date Created: Dec 2011

This document is confidential and the copyright of AECOM Limited. Any unauthorised reproduction or usage by any person other than the addressee is strictly prohibited.


Executive Summary

This report has been produced on behalf of Glasgow City Council, North Lanarkshire Council, and the Glasgow and Clyde Valley Green Network Partnership for the purpose of presenting a Hydrological Study for the Gartloch and Gartcosh area. 2

The site area encompasses c.24km located within the central belt of Scotland and which lies within the boundaries of both Glasgow City Council and North Lanarkshire Council. This report provides an assessment of flood risk from the watercourses in the area including a hydrological assessment to define the potential flood areas under various Annual Exceedance Probabilities (AEP) up to 0.2%. An additional allowance to account for estimated future climate change has being assessed for the 3.33% AEP and 0.5% AEP scenarios. This report also provides consideration of the sewerage system in the area and interactions with the surface water regime. Consultation has being carried out for this report with stakeholders including Glasgow City Council, North Lanarkshire Council, Glasgow and Clyde Valley Green Network Partnership, The Coal Authority, SEPA and Scottish Water. This document sets out to establish a baseline of the site to support the design study process by investigating all sources of flooding, including fluvial and pluvial flooding under a range of annual exceedance probabilities (AEP) which may create significant constraints for the site and provide the principles for future drainage provision, which optimises the balance of environmental constraints with the regeneration and design study aspirations and introduces a concept for how the future surface water management of the site can be developed. One of the aims of this project is to propose to integrate a hydrological strategy for successful current and future management of existing water bodies within the framework of a wetland park. In addition, a separate Surface Water Management Strategy (SWMS) has been prepared following the guidance and requirements set out in Scottish Planning Policy (SPP) and to meet the guidance of CIRIA 697 – The SuDS Manual, and Controlled Activity Regulations – The Water Environment (Controlled Activities) (Scotland) Regulations 2005.


Table of Contents

1

Introduction ....................................................................................................................................................................... 1

2

Data Collection .................................................................................................................................................................. 5

3

Hydrogeology .................................................................................................................................................................. 11

4

Hydrology ........................................................................................................................................................................ 15

5

Hydraulic Modelling ........................................................................................................................................................ 25

6

Results ............................................................................................................................................................................. 41

7

Summary .......................................................................................................................................................................... 43


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Introduction

1.1 Background This report forms part of the study of the Gartloch and Gartcosh area that is being undertaken by Glasgow City Council (GCC), North Lanarkshire Council (NLC) and the Glasgow and Clyde Valley Green Network Partnership (CVGNP). The hydrological study aims to further inform the masterplanning processes to assist with the sustainable development objectives of the Community Growth Areas (CGAs) in eastern Glasgow and at Gartcosh and Glenboig in North Lanarkshire. The long term vision for the Gartloch / Gartcosh site is to create a wetland park of national significance provisionally named ‘The Seven Lochs Wetland Park’. The challenge is to blend predicted community growth with the natural environment. Flood risk and drainage of surface water are at the root of this vision and so an understanding is sought of the hydrological interactions within the area, giving the partnership information to take forward the sensitive blending of community growth and the existing water environment in a surface water management plan and community masterplan. The holistic approach will assist the partnership in fulfilling five underlying objectives of the Metropolitan Glasgow Strategic Drainage Plan (MGSDP). 1. Flood risk reduction 2. River water quality improvement 3. Enabling economic development 4. Habitat improvement 5. Integrated investment planning AECOM have prepared a hydrological study for the site and a separate Surface Water Management Strategy. This includes the definition of areas that would flood for return periods of 50%, 10%, 3.33%, 2%, 1%, 0.5% and 0.2% AEP events (2, 10, 30, 50, 100, 200 and 500 year return periods) with consideration given to a climate change allowance of 30%. The study includes consideration of the sewerage system involving Integrated Drainage Models and reference to the interactions with the surface water regime. 1.2 Location The study area is located within the central belt of Scotland lying within the boundaries of both Glasgow City Council and North 2 Lanarkshire Council and forms parts of the Glasgow Green Belt, with the site encompassing approximately 24km . The plan in Figure 1.1 shows the extent of the study area which stretches from Hogganfield Loch in the west to Woodend Loch and Lochend Loch in the east. The western edge of the site is situated 5km to the east of Glasgow City Centre. The study area stretches for 8.7km east to west at its widest extents from the east end of Glasgow towards Coatbridge in North Lanarkshire. The location within the central belt provides an opportunity for the study area to be of national significance with the creation of a new wetland park with good transport connections. The park boundary connects directly to the eastern edge of the Glasgow City metropolis, with Coatbridge lying to the eastern edge of the proposed park, shown in Figure 1.2, Appendix D. The park is surrounded by established communities on all sides.


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Figure 1.1: Hydrological Study Area

Š Crown copyright and database right 2012. All rights reserved. Ordnance Survey Licence Number 1000332510

Council Boundary Study Area Boundary

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1.3 Site Composition Much of the area is low lying rural in character and mainly undeveloped. The site is surrounded by low density housing developments on all sides. The land is principally planar in character interspersed with a number of small drumlins and consisting of open fields and hedgerows. There are large traces of historic peat cutting and former mining activities such as bings. A substantial proportion of the study area is composed of natural or semi-natural open green space in the form of open water, woodland, wetland and moss. There are pockets of scattered woodland which include field boundaries and riparian corridors as well as plantation, community, mature estate and dense semi-natural woodland, along with substantial peat deposits. Two large public parks, Drumpellier and Hogganfield Parks, are located along the periphery of the study area. Water is a dominant feature of the landscape in the form of open water, burns and seasonally flooded or persistently wet ground with a complex catchment area converging on the Bothlin Burn then draining to the east and north. The site contains multiple wetlands including seven shallow kettle ponds or ‘depressions’ formed by the glacial retreat during the last ice age and referred to as the ‘Garnkirk chain’. Interspersed within the wetlands are areas of agricultural land (both working and fallow), and areas of ancient and long established woodland and grassland. The site is of considerable ecological importance for wildlife and contains one of the largest reed bed habitats in central Scotland. Along with the lochs there are a number of watercourses, drainage ditches, small ponds and wetlands which form a complex system along which water moves through the area. The natural lochs vary from the extensively modified banks of Hogganfield and Lochend Loch to the agricultural boundaries of Gartloch Ponds through to the well vegetated margins of Bishop Loch and Woodend Loch. Several drainage ditches have become blocked, either accidentally or deliberately, whilst others have become blocked through the natural process of siltation. The main water bodies of the study area include: • Hogganfield Loch • Frankfield Loch • Bishop Loch • Johnston Loch • Lochend Loch • Woodend Loch • The ponds and pools of Gartloch Local Nature Reserve and Garnqueen Loch • The emerging Gartloch Pools; (new pools emerging at Gartloch may be the result of former mining activity) The main watercourses within the area include: • Bothlin Burn • Molendinar Burn • Bishop Burn • Tolcross Burn • Whamflet Burn Existing area designations on the site include Sites of Special Scientific Interest (SSSI), Local Nature Reserves (LNR) and a country park at Drumpellier.


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Figure 1.3: Site Characteristics

Images provided by Collective Architecture.

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Data Collection

2.1 Background Documents A number of sources have being used to collate background hydrological and hydrogeological information about the area. These are included in Table 2.1 below. Table 2.1: Background data Data Type

Data Name

Source

General spatial data

GIS layer indicating study site boundary

GCC/NLC

LiDAR / DTM data OS Mapping - Mastermap, 1:10k, 1:50k Aerial Photography Strategic Environmental Planning Study for Easterhouse / Gartloch Area Cityplan 2 GIS layers Core paths Landscape / ecological / cultural designations IHN Habitat Modelling Utilities / Services information

GCC/NLC GCC/NLC GCC/NLC GCC GCC GCC/NLC GCC/NLC GCV GCC/NLC

Sewer flood risk

GL01 Dalmarnock sewer network model GL02 Dalmuir sewer network model NL09 Daldowie sewer network model (Coatbridge DAP model) Historic sewer flooding information

SW SW SW SW

Hydrological/ Fluvial flood risk

Historic flood information e.g. mapping, reports SEPA digital flood maps

GCC/NLC GCC/NLC

Flood risk assessment reports -Gartloch Farm -Drumpellier Lawns, Bargeddie Drainage Assessment (T.Lawrie & Partners) -Drumpellier Lawns, Bargeddie Flood Assessment (Envirocentre) -Lochend, Easterhouse Flood Assessment & Drainage Review (Kaya Consulting) -Frankfield Loch, Stepps, Environmental Statement (Keppie) Bothlin Burn @ Auchengeich gauging data Molendinar Burn pumping system info

GCC/NLC

Tolcross Burn manhole survey Whamflet Burn manhole survey IDP model cross section data National Pluvial dataset

SEPA Strathclyde University Estates GCC GCC GCC/Halcrow GCC


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Data Type

Data Name

Source

Hydrogeological

Geological Mapping Geological Mapping Groundwater Level Data Groundwater Level Data Groundwater Level Data Groundwater Quality Data Groundwater Quality Data Groundwater Quality Data Previous Site Investigation Data Previous Site Investigation Data Previous Site Investigation Data Mine Abandonment Plans Mine Dewatering History/Records

Shallow mine workings polygons (shape / tab files) minewater discharges

GCC NLC and/or BGS GCC NLC BGS GCC NLC BGS GCC NLC BGS GCC/NLC and BGS GCC/NLC and SEPA/CA and BGS GCC NLC GCC/NLC and SEPA/CA GCC or CA CA

Seven Lochs Wetland Park - Draft Masterplan and visioning study

Collective Architecture

Historical Mapping Historical Mapping Minewater Pollution Incidents

Masterplan

2.2 Topographic Survey and Ground Model Data A topographical survey of the watercourses in the site boundary was specified by AECOM and carried out by Loy surveys Ltd in April 2011. This resulted in a substantial amount of detailed topographic data including river cross-sections of the Bothlin Burn, Molendinar Burn and Bishop Burn at approximate 25m to 50m intervals, and any structures on the watercourses. No survey data was specified on the Tolcross Burn and Whamflet Burn as these watercourses were already included in network models. The accuracy of the survey is commensurate with 1:500 scale as detailed in the RICS publication: ‘Specification for Surveys of Land, Buildings and Utility Services at scales 1:500 and larger’. The topographic survey data was enhanced by LiDAR data, made available from GCC, and NextMap data from NLC. The more accurate LiDAR covers the majority of the site, with small areas to the east and north east of the site covered only by Nextmap, shown in Figure 2.1, Appendix D. The LiDAR and Nextmap data was used to generate a ground model for use by the hydraulic model to extend surveyed cross sections into the floodplain, and to determine floodplain storage areas. Nextmap has a stated vertical accuracy of + 1.0m, and horizontal accuracy of + 2.5m, which is insufficient for floodplain mapping required for this project. Topographic survey of this floodplain area at 10m postings was considered but rejected as too costly. Instead surveyed river sections were extended 10m from either bank into the floodplain, rather than the 5m specified elsewhere, to give an overlap of 20m at each river cross section between surveyed levels and Nextmap data.


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Surveyed levels in overbank areas were then compared with Nextmap levels at the 72 sections outwith the LiDAR coverage. This exercise ascertained that there was no consistent difference between surveyed and Nextmap levels to allow the Nextmap data to be corrected by single value. Where surveyed sections within this area required to be extended to accommodate the flows being modelled, this was done in the first instance using Nextmap data. The level difference between the last surveyed point at each end of the section and the Nextmap data was then determined, and the extended lengths of the section corrected by this difference. A further issue with the ground model within the area covered by LiDAR was also identified. Whilst undertaking hydraulic modelling of the Bothlin Burn, it became apparent that there were anomolous ground levels in the area downstream of Bishop Loch. This area is marshy and was overgrown with scrubby vegetation and tall grasses when the site was visited in January 2011. Inspection of the LiDAR levels in this area indicate ground levels in the region of 1 – 1.6 m higher than the loch level indicated by the LiDAR data (see Figure 2.2), and a similar amount higher than the topographic survey data in the area. It is considered that the anomaly in ground levels in this area is due to the post-processing procedure used to produce the “bare earth� digital terrain model from the raw survey data. Buildings and vegetation are removed from raw elevation data using an algorithm. It is possible that this area has not been identified as heavily vegetated, and resulting LiDAR levels are higher than ground level. The area sits within the Seven Lochs Wetland Park, and may play an important role in the development of the Wetland Park with a proposal to create a new wetland area in this location. The area also provides the only realistic location in which flood attenuation could be located within the catchment to reduce flooding downstream. Accurate ground levels are therefore required to enable this to be accurately assessed. Further topographic survey was specified in this area to allow the ground model to be adjusted to more accurately reflect actual ground levels. Some additional survey was carried out in July 2011; however, due to the ground conditions, the coverage of point levels that could be surveyed without compromising health and safety of the survey team was limited and served only to confirm the previously estimated anomaly in levels. Ground levels in this area were therefore reduced wholesale by a figure of 1.3m. The resulting modelled flood levels, flood extents and pass forward flows in this area will therefore be less accurate than the remainder of the model. New survey data of the outlet at Hogganfield Loch was received from David Robertson of GCC, which clarified some issues but some uncertainties remain regarding pipe connections downstream. These could only be clarified by CCTV survey which is outwith the scope of this project. The model accuracy may therefore be compromised in this area.


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Figure 2.2: Area of anomalous LiDAR data

Š Crown copyright and database right 2012. All rights reserved. Ordnance Survey Licence Number 1000332510

2.3 Pluvial Data Set AECOM received pluvial outlines for the 200 year and 30 year events from GCC. These were generated by JBA Consulting in 2010, and are described in Glasgow Pluvial Flood Map, Methodology Report, Draft Report, September 2010. These outlines do not include for climate change. The outlines were used to visually compare modelled flood extents and check locations of low ground levels, and used in more detail in the development of the Surface Water Management Strategy. 2.4 Integrated Drainage Plan(s) This study encompassed an assessment of the sewerage and drainage systems within the study area to evaluate and their interaction with the wider surface water regime. The study area is covered by three Scottish Water drainage areas, Dalmarnock, Dalmuir and Daldowie. The catchment models for Dalmarnock and Dalmuir were provided by Scottish Water for use in this study. The Daldowie model was not incorporated into the assessment as only a very small area of the site is within the drainage catchment and the surface water drainage impact is negligible. The existing Scottish Water sewer models were used to review and assess the interaction with the surface water system for the area. The affect of the surface water flow interaction was then included in the hydraulic modelling of the watercourses, ponds and wetlands system within the study area.


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2.5 Historic Data No historic flood outlines exist for the area. 2.6 Molendinar Burn Pumping Station Frankfield Loch is linked via the Molendinar Burn to Hogganfield Loch. Downstream of Frankfield Loch, the watercourse flows through Strathclyde University playing fields at Stepps. Originally the Molendinar Burn flowed naturally into the Hogganfield Loch under a small vertical difference. The small vertical difference inhibited natural drainage and resulted in flooding upstream. In addition, it is understood that Hogganfield Loch levels were raised artificially for recreational purposes. As a result, a pumping station was installed on the Molendinar Burn at the western boundary of the playing fields at Avenue End Road, and maintained by Strathclyde University (Figure 2.3 and 2.4). The pumping of water in the Molendinar Burn is controlled by float switches and thus the water levels in the Molendinar Burn and hence Frankfield Loch are maintained. There are 2 pumps, operating as duty/standby and each has a capacity of 94 l/s. Data on the pump capacity was collated from site vists and information from the pump manufacturer, with Strathclyde University Estates Department providing drawings of the downstream pipe arrangement. No drawings of the pumping station itself were available, so this was included in the specification for topographic survey. Figure 2.3: Location of Molendinar pumping station

Figure 2.4: Molendinar Pumping Station

Š Crown copyright and database right 2012. All rights reserved. Ordnance Survey Licence Number 1000332510

2.7 Hydrogeology Data has been taken from existing site investigation reports for the areas (either reviewed at the GCC archive or obtained from NLC and/or BGS information), mine abandonment plans and historic maps. The spatial distribution of this data is varied, with some areas having very limited data (comprising of only a few boreholes) and others more extensive coverage. Limited data is available around: Gilmoreneuk, Bishop Loch and Gartloch Cottages, Cardowan Moss, Gartcosh, Johnston Loch and Mount Ellen, Mount Ellen Golf Club and former Drumcaval Quarry, and Heathfield Cottage and fields south of the railway. A slightly larger amount of data (e.g. an older site investigation or several boreholes) is available for: Commonhead/Neatherhouse area, Townhead/ Lochend Loch, Woodend Loch, West Cottages/Gartloch Pool, Blackfaulds Farm, Frankfield Loch and surrounding fields, Garnkirk, Heathfield Moss and the Garnqueen/Marnoch area. Good data (comprising either a thorough recent investigation, or several older investigations) is available for: Baillie Moss, Garcloss Farm, and the Former Gartloch Hospital.


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The areas of Easterhouse, Glasgow Fort, and the former Gartcosh Steelworks have been extensively investigated in the past, and represent locations of the largest quantity and best quality of information. Summarised below are the types of data sources. Appendix A lists all site investigation reports reviewed for hydrogeology, and includes relevant comments on each. Table 2.2 Hydrogeological Data Sources Data type

Geological Mapping

Groundwater Level Data Groundwater Quality Data

Source

Comments

GCC

generally confirmed by SI data

NLC- geotech leader David Millar

generally confirmed by SI data from GCC

GCC and NLC geotechnical archives, BGS website GCC and NLC geotechnical archives

sporadic data; fairly limited spatially, Fairly limited in NLC area sporadic data; fairly limited spatially, Fairly limited in NLC area

Historic OS Mapping

GCC GIS database, NLC hardcopies of maps

Complete

Mine Abandonment Plans

mine abandonment plans

Reviewed at the BGS but did not provide much information; some water pumps shown occasionally with productivity amounts

GCC GIS database, NLC hardcopies of maps

Complete

Scottish Water

Not available

CA Archivist (Mark Gilmore)

no data for the 3 main collieries

SEPA Hydrogeologist (Judith Clarke)

no data

BGS internal report

limited data

Minewater Pollution Incidents

SEPA Hydrogeology, Judith Clarke

no data

Minewater discharges

CA Hydrogeologist- Ian Watson

discharge volumes too low to have an effect.

Shallow mine workings polygons (shape/tab files) Mine Dewatering History/Records

GCC – Glasgow City Council NLC – North Lanarkshire Council SEPA – Scottish Environment Protection Agency BGS – British Geological Survey CA – The Coal Authority


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Hydrogeology

3.1 Introduction The groundwater studies are built on the information collated for the 2009 Scoping Study. In particular, records and data relating to historic mining and the associated groundwater management and water levels have been collected from available sources. Mining (particularily shallow coal mining) has been extensive in the area. The primary hydrological issues related to this are the potential for current discharges from mine workings and future discharges. If the process of groundwater rebound following cessation of mining is still ongoing, the water table will rise across most of the site area. This may affect the extent and hydrology of existing water bodies and wetland areas, and areas which have historically been dry may flood. Groundwater data has been collated from a variety of sources, with the primary objective of determining the extent with which groundwater locally interacts with surface water, as well as the likelihood of any ongoing minewater rebound creating a future interaction and adversely affecting surface water quality. 3.2 Geological Conditions 3.2.1 Superficial Deposits Superficial deposits underlying the site typically comprise Glacial Till, with Lacustrine and/or Peat deposits along watercourses and in low-lying areas. Superficial Deposits are typically between 5m and 15m thick, although there are locations where they are not recorded by the BGS. The Glacial Till generally comprises a sandy clay, with occasional cobbles and boulders. The Glacial Till is overlain by Lacustrine deposits primarily along the Molendinar and Bothlin Burns, while Peat deposits are recorded along the Bothlin Burn where it exits Bishop Loch, north of Gartcloss Farm. Made Ground has been encountered locally in site investigations. 3.2.2 Bedrock Geology Bedrock geology primarily consists of the productive Upper, Middle, and Lower Coal Measures and the Passage Formation of Namurian age. The Passage Formation has been mined in the past for fireclay and limestone. A few igneous sills exist onsite. Western Midland Valley Westphalian to Early Permian sills exist in the Glenboig area, in the north-east of the site. Permian age ophitic alkali olivine-dolerite sills exist in the south-west corner of the site, at the western edge of Easterhouse. 3.2.3 Mining Coal mining was a major part of the economy in the area for almost 100 years. Collieries generally closed from the middle of the 20th century, with the last one shutting in 1985. Coal was mined at various locations in the southern half of the site, to the south of the Comadie Fault. Less extensive Coal and Fire Clay workings are present in part of the Millstone Grit sequence in the north of the site (in an approximate line from Craigendmuir to Garnqueen). Carboniferous Limestone was a minor component of the mining heritage of this area, with a few quarries in the far north of the site, near Drumcaval, and to the west of the site. Shallow coal mining has taken place primarily in the vicinity of Easterhouse and Drumpellier (approximately the south-eastern quarter of the site). However, less extensive areas of shallow mining are recorded further west, see Figure 3.1. A property to the north-east of Blackfaulds Farm further west reported subsidence problems (reported as “new sits�) in 1973.


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Figure 3.1 Shallow mining and minewater discharges

Š Crown copyright and database right 2012. All rights reserved. Ordnance Survey Licence Number 1000332510

3.3 Groundwater 3.3.1 Level Groundwater level data was inferred through a review of Site Investigation Reports, Mine Dewatering History/Records, and Minewater discharges. Unfortunately, because the available groundwater level data is sporadic and most records do not include Ordnance Datum information, it is not possible to produce meaningful groundwater contours and interpretation of groundwater levels in different parts of the site can only be indicative. Shallow Groundwater Shallow groundwater, in the superficial deposits, is sporadically present, indicating locally perched groundwater. The depths at which such groundwater is recorded ranges from 0.5mgbl to 6.08mbgl, with enough variety that nothing definitive can be stated. It is likely that the presence of significant perched groundwater in the superficial deposits is closely linked to surface water features. An area to the east of Blackfaulds Farm was investigated in 2000; this found that the eastern portion of that site, along the Bothlin Burn,(approximate grid reference 666850 267200) was generally flooded (in keeping with the most recent aerial photos) and is


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approximately coincident with the western edge of the newly formed Gartloch Pool. An investigation located a short distance to the east, at the former Gartloch Hospital site stated that the "groundwater level is consistent with Bishop's Loch". Bedrock Groundwater Groundwater in the southern half of the site was typically at or near top of bedrock. Investigations in the north are more sparse, but the water table appears to be at a greater depth. As might be expected, the depth to groundwater associated with the former mineworkings varied significantly, with the shallowest forming a surface resurgence (Figure 3.1) and the deepest noted at approximately 30m bgl. At Kilgarth Landfill (667850 271711), groundwater is generally present within 7 metres of the ground surface and varies from being encountered in the rock near rockhead to being encountered as a “heavy flow� in the mine waste at depth. Four pump tests undertaken in association with the proposed quarry at the aforementioned Ballie Moss Wood site did not find a hydraulic connection between Woodend Loch and Bishops Loch; however, some criticism of the testing implied that the duration of the test was too short. The results of the tests and conclusions drawn by others, along with our limited information on bedrock groundwater levels, infer that the lochs are fed by surface water and shallow groundwater flows and are not connected to bedrock groundwater. 3.3.2 Groundwater Quality No minewater pollution incidents have been indicated by the Coal Authority. Chemical testing of the known onsite minewater resurgence indicated a neutral pH and elevated sulphate, sodium, and potassium. Coal Authority records indicate Total Iron at 3.91 mg/l. Localised sources of contamination are understood to exist onsite, however available groundwater testing did not indicate extensive sources. It is anticipated that some degree of groundwater contamination will be associated with the former Gartcosh Steelworks, but our enquiries with the two councils and SEPA did not glean any information in this regard. 3.4 Anticipated Interaction with Surface Water 3.4.1 General Comments Only one minewater discharge is known from The Coal Authority to exist onsite, with three others in the vicinity (Figure 3.1). Many records of historic minewater pumping have been sourced. They are all from depths of greater than 300m. Given the depth and dates when the various areas of pumping ceased, 1956 to 1985 (Figure 3.1), along with the historical map review not indicating any additional pre-mining surface water or wetland features, suggests there is unlikely to be a significant future change in water table levels related to mine-water rebound. In addition, the level data available for the bedrock water table, although limited, suggests that there is likely to be limited current interaction with surface water and not anticipated to affect the flood hydrology. 3.4.2 Frankfield Loch At the start of the study, the hydrology of the loch was unclear, particularly what inflows may exist. It was therefore intended to undertake a specific review of groundwater and mining data for this area. Unfortunately, no groundwater information was obtained for the vicinity of Frankfield Loch. Superficial deposits are noted to be Glacial Till (generally a brown sandy clay), with a thickness in excess of 9m. There are no known minewater discharges, mineshafts/adits or shallow mine workings in the vicinity of the loch. It is therefore considered unlikely that Frankfield Loch is significantly affected by minewaters or, given the Glacial Till thickness, any bedrock groundwater.. 3.4.3 Gartloch Pool This study set out to determine how Gartloch Pool (on the north side of Gartloch Road, grid reference 267230, 667300) formed, and to test the hypothesis that it was created through minewater discharges or influenced by these.


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• Minewater is considered unlikely to be a significant factor in the formation of this pool. The reasons and evidence against this include: a visual inspection of the pool indicates that it is of a higher quality (e.g. no iron staining) than typically found from mine water discharges; • no mineshafts/adits or indication of known shallow mine workings in the vicinity or immediately up gradient. • none of the minewater discharges known by the Coal Authority are in this area. Two possible alternative formation mechanisms for the pond have been derived: • discussions with Donald Linn at GCC Geotechnical Dept (DRS) and a review of a stereoscopic photograph set from the late 1940s suggest that it was more likely due to a blocked road culvert. The pond corresponds to the location of a road culvert taking the Bothlin Burn under Gartloch Road and therefore if it was significantly blocked the burn would flood in the location of Gartloch Pond. If this theory is correct, the more recent ponding to the south of the road would stem from an alternate source. • boreholes associated with the Gartheugh Sewer were drilled along the north-west side of Gartloch Pool. No date is given on the logs, but as they are handwritten and in fathoms-feet-inches it is presumed that they are pre-1970s. It is not known at this stage if this sewer was built, but if it was and is now leaking it may be partly or wholly responsible for the pond.


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Hydrology

4.1 Gartloch / Gartcosh Description The Gartloch / Gartcosh study area comprises a total area of 24 km2. The annual average rainfall varies across the catchment is between 923mm and 1052mm with the highest average rainfall occurring over the northwest to western areas of the catchment. The site is a complex network of drainage ditches, lochs, wetland, seasonal waterbodies and ponds. There are burns flowing through the site, which are tributaries of both the River Clyde and River Kelvin. The principal watercourses in the catchment include: •

the Bothlin Burn;

the Molendinar Burn;

the Bishop Burn;

the Whamflet Burn

the Tolcross Burn.

The Bothlin Burn drains the majority of the study area. The burn initially flows east, and then northwards towards Kirkintilloch and through a number of lochs located within the study area, including Gartloch Pools, Bishops Loch, Lochend Loch, Woodend Loch and Johnston Loch. The Molendinar Burn is located in the north west corner of the study area and flows south west from Stepps, through Frankfield Loch and discharges into Hogganfield Loch. The Bishop Burn flows south west from Drumpellier Park near the south east boundary of the study area, below the Monkland Canal, before turning south and discharging into the Luggie Burn. The Whamflet and Tolcross Burns are located in the south of the study area. The Whamflet burn is largely culverted, draining an area of Easterhouse north of the M8. Following a short open channel reach between Springhill Parkway and Easterhouse Road, it joins the Tolcross Burn near the station at Swinton. The Tolcross Burn drains Commonhead Moss to the east of Easterhouse, and flows west beneath the M8 motorway to join the Whamflet Burn. Thereafter, the watercourse continues west along the line of the railway. Figure 4.1, Appendix D shows the principal hydraulic features of the study area, and Figure 4.2, Appendix D indicates the catchment areas for each watercourse. 4.3 Hydrometric Data Hydrometric data describes the regime of a river, its catchment and how it responds to rainfall events. Information concerning water levels and river flows within the study catchment informs our understanding of the hydrological processes and improves our estimates of flood flows. Flood estimates made using observed, local flow data are considered to be more reliable than those based on catchment properties and empirical equations alone. Flow data was available for the Bothlin Burn from the SEPA gauge at Auchengeich (Gauge no 84023, OS NGR NS 67800 71600), which lies some 5.5 km downstream of the northern edge of the study boundary. Annual maximum data was available for this gauge from 1972. No other hydrometric data was available for any other watercourse within the study area. 4.4 Hydrological Modelling Methodologies The Flood Estimation Handbook (FEH) is considered to represent best practice with regard to estimating design flood flows in the UK, and is appropriate for use in this flood mapping project. The FEH advocates use of both a statistical methodology and rainfall-runoff methodology for estimating the design flows for the AEP events listed in Table 4.1.


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The statistical method is usually considered to be the most suitable method of estimating design flows on UK river catchments, since it is based on observed flow data from approximately 1000 gauging stations. This methodology incorporates the effects of reservoirs and floodplain storage on river flows and an adjustment procedure is available for application to permeable catchments. In contrast, the rainfall-runoff approach is calibrated against a much smaller data-set of 143 UK catchments. This methodology does not account for attenuation in the catchment, and consequently usually generates larger flow estimates. 1, 2

A number of papers have reported that the FSR/FEH rainfall-runoff method has a tendency to generate design flows of excessive magnitude and consequently the statistical approach is usually preferred. In January 2006 the Revitalised Flood Hydrograph (ReFH) rainfall-runoff method was released in an attempt to bring the FSR/FEH rainfall-runoff model into line with the statistical method. The ReFH model has been calibrated against 101 catchments. However, ReFH is not recommended for use in permeable, or urban catchments since none of the catchments used for calibration were permeable and there were very few urban catchments included. It is also not recommended for use in Scotland, as it has not been calibrated against any Scottish catchments. As a result the statistical method is still considered to provide the most robust flow estimates since it is based on the larger dataset and is the most applicable method for the study. However, the FEH statistical methodology only provides the user with an estimate of the peak flow, whereas the rainfall-runoff methods provide a peak flow and a full hydrograph. In addition, it is less robust for smaller catchment areas since the number of gauges measuring data from small catchment areas is low within the database of gauging stations. The following discussions introduce how the hydrological modelling methodology was developed for the Gartloch hydraulic model. 4.5

Bothlin Burn Hydrological modelling

4.5.1 Peak flow estimates Peak flow estimates for the Bothlin Burn at the study area boundary were derived using the FEH statistical method. The Auchengeich gauge was used as a donor gauge to determine the QMED (median annual flow), and a pooled curve derived to generate peak flow estimates for the Annual Exceedence Probability (AEP) events required. The FEH statistical method involves three steps: • Estimation of the index flood (QMED) • Derivation of the growth curve using a pooled group of hydrologically similar gauged catchments • Construction of the flood frequency curve, as a product of QMED and the growth curve. QMED was estimated for the Bothlin Burn using catchment characteristics derived from the FEH CDROM. An empirical equation is provided in the FEH to estimate QMED from catchment characteristics. This figure was then adjusted using the observed QMED for the Auchengeich gauge. A pooled growth curve was then generated using WINFAP v3 software, which automatically generates a pooling group of hydrologically similar gauged catchments. Manual adjustment can then be undertaken to add, delete, promote or demote gauging stations within the pooling group, based on user expertise. Full details of the flow calculations are included in Appendix B. The resulting peak flow estimates, measured at the catchment outlet are shown in Table 4.1.

1

Spencer, P. and Walsh, P., (1999). The Flood Estimation Handbook: Users’ perspectives from North West England. In: Proc. 34th MAFF Conf. River and Coastal Engineers, Keele, UK. 2 Ashfaq, A. and Webster, P., (2002). Evaluation of the FEH rainfall-runoff method for catchments in the UK. J. CIWEM, 16, No. 3, 223-228.


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Table 4.1: Bothlin Burn peak flow estimates 3

AEP %

Return period

Peak flow (m /s)

50%

2 year

6.1

10%

10 year

9.7

3.33%

30 year

12.2

2%

50 year

13.5

1%

100 year

15.3

0.5%

200 year

17.4

0.2%

500 year

20.5

4.5.2 Sub-catchment inflows With the large number of lochs and wetlands within the catchment, it is important that the behaviour of water levels and storage volumes are represented in the hydraulic model. To do this accurately, full hydrographs of flow against time are required, not just a peak flow estimate. The Bothlin Burn catchment was split into subcatchments to represent inflow points to the hydraulic model. Any lateral inflow from catchment areas between the inflow points were also accounted for. Catchment characteristics for the subcatchments are shown in Appendix C and the inflow points are located in Figure 4.3, Appendix D. Using the FEH rainfall-runoff method, flood hydrographs were generated for each subcatchment and for each lateral inflow for the AEP events required. A diagrammatic representation of the flow inputs is shown in Figure 4.4. Once input into the hydraulic model, the subcatchment hydrographs were scaled such that the cumulative flow at the catchment outlet matched the statistical method estimates shown in Table 4.1.


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Figure 4.4: Bothlin Burn inflow diagram

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4.6 Molendinar Burn The Molendinar Burn flows south west from Stepps through a marshy area east of Loch Road towards Frankfield Loch. Previous hydrological reports suggest that the burn discharged into Frankfield Loch through a culvert beneath Loch Road. However, the culvert could not be located during site visits and it is thought that it has been removed or abandoned following raising of Loch Road, carried out in conjunction with the Frankfield Loch Development, recently constructed to the east of the loch. A new culvert has been provided at a higher level (Figure 4.5). A ditch has been cut from the Molendinar Burn just to the east of Loch Road that runs northwards before entering a culvert beneath Cumbernauld Road (Figure 4.6), and is thought to discharge into the Garnkirk Burn to the north of the railway line. Comparison of surveyed levels of the watercourse, structures and loch level suggest that, certainly at lower flows, the Molendinar Burn upstream of Frankfield Loch is entirely diverted into the Garnkirk Burn. Water would flow from Frankfield Loch east through the new culvert and into the Molendinar Burn, from where it would discharge into the Garnkirk Burn. Figure 4.5: New culvert below Loch Road West (Frankfield Loch) side of culvert

Figure 4.6: Diversion ditch to Garnkirk Burn

East side of culvert


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At the west side of Frankfield Loch, the Molendinar Burn flows west through Strathclyde University playing fields to a pumping station located just east of Avenue End Road. The pumped flow then enters a culverted reach which discharges into Hogganfield Loch. The Molendinar is then discharged from Hogganfield Loch via a piped section into an open channel reach to the east of Cumbernauld Road. The Molendinar Burn was split into subcatchments located in Figure 4.7, and shown diagrammatically in Figure 4.8. Catchment 2 descriptors are shown in Appendix C. The Molendinar Burn in this location has a small catchment area of only 2.34km to the outlet of Hogganfield Loch. Because of this small catchment size, and due to the lack of any gauged data on the watercourse, the FEH statistical method was inappropriate. The FEH rainfall-runoff method was therefore used to generate flood hydrographs of the required AEP events.


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Figure 4.7: Molendinar inflow points

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Figure 4.8: Molendinar inflow diagram

4.7 Bishop Burn The Bishop Burn flows through the south east corner of the Gartloch/Gartcosh site area. It drains much of Drumpellier Country Park, flowing south west out of the park, beneath the Monkland Canal, Oakridge Road and Coatbridge Road, before discharging into the Luggie Burn. The Bishopburn waste weir on the Monkland Canal discharges excess water from the canal into the Bishop Burn. However previous modelling of the canal by AECOM suggests the weir does not discharge during events up to and including the 0.5% AEP.


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Similar to the Molendinar Burn, the catchment area of Bishop Burn is small, and there is no gauging data available. Consequently, the rainfall runoff method has been used to generate inflow hydrographs for the hydraulic model. The catchment characteristics used are shown in Appendix C and Figure 4.9 below locates the inflow point and waste weir. Figure 4.9: Bishop Burn Inflow Point

Š Crown copyright and database right 2012. All rights reserved. Ordnance Survey Licence Number 1000332510


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4.8 Tolcross and Whamflet Burns The Tolcross and Whamflet Burns are explicitly represented in the Dalmarnock IDP model. As such, there was no requirement to construct new models of the watercourses and consequently no requirement to generate inflow hydrographs. The exception was for the rural subcatchment at the upstream end of the Tolcross Burn. The audit report on the IDP model suggested this would be better represented by an FEH rainfall-runoff boundary. This amendment was made in the model. The catchment characteristics used can be found in Appendix C. 4.9 Summary The principal objective of this hydrological assessment was to derive the design flood hydrology for the Gartloch / Gartcosh catchment, to inform the hydraulic modelling component of the flood mapping. FEH statistical methodology was applied to determine design flow estimates for the Bothlin Burn, using the flow gauging record on the Bothlin Burn at Auchengeich as a donor for data transfer. Hydrographs for subcatchments within the total catchment of Bothlin Burn were estimated using the FEH rainfall runoff method, which were then scaled to match the statistical estimate. For the remaining watercourses, catchment areas were too small and there was no suitable donor gauges for the FEH statistical method to be applied robustly. Flow estimates on these watercourses were estimated using the FEH rainfall runoff method.


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Hydraulic Modelling

5.1 Introduction A hydraulic model of the Gartloch / Gartcosh watercourses throughout the study area was constructed using Infoworks RS hydraulic modelling and mapping software. Infoworks RS is recognised industry software for use in river modelling and hydraulic analysis, which combines the industry standard 1D ISIS flow engine with GIS functionality and a database storage structure. The objectives of the modelling are to model the fluvial flood extents within the Gartloch / Gartcosh catchment by constructing 1D hydrodynamic models of the watercourses within the study area. In the hydraulic models, data used for the physical representation of the river channels, bridges and culverts have been taken from the topographic survey carried out in April 2011 for Bothlin Burn, and in July for Molendinar Burn and Bishop Burn. LiDAR data provided by Glasgow City Council, and Nextmap provided by North Lanarkshire Council was used in representing the out of bank floodplain areas within the model reach. In order to be able to identify and map the areas of inundation within the study area, it was necessary to estimate the magnitude of design flow events for the hydraulic model. To derive the design flows required, it is necessary to develop an understanding of the flood hydrology of the catchment and undertake an analysis of the hydrometric data available. This leads to an informed hydrological modelling analysis that derives a sensible set of flood estimates for the various Annual Exceedence Probability (AEP) events required. The flow estimation procedures employed are discussed in detail in Chapter 4. The extent of the study/model extents was constructed to the following downstream boundaries: • • • • 5.2

Bothlin Burn – to the crossing of the A80; Whamflet Burn/Tolcross Burn – to the A8 Bishop Burn – to downstream of Coatbridge road; Molendinar Burn – to the outlet of Hogganfield Loch; Bothlin Burn Model

5.2.1 Design Events A broad spectrum of design events were run for the hydraulic model which included the 50%, 20%, 10%, 3.33%, 3.33% +30% CC, 2%, 1%, 0.5%, 0.5%+30% CC and 0.2% scenarios. Unsteady state runs were also carried out for each of the above AEP scenarios with critical storm durations based on both the total catchment and the individual sub-catchments. The rainfall runoff method is based on a design rainfall event of specified duration. Short storm durations will give hydrographs with a high peak but low volume, and conversely long storm durations will give hydrographs with a lower peak but larger flood volume. The critical event for any catchment is a function of the combination of flood peak and volume, and the critical duration will tend to increase with catchment area. Therefore modelling one critical duration for the total catchment area to the downstream point, may underestimate peak water levels in areas higher up the catchment. By modelling both subcatchment and total catchment critical durations, it is ensured that the maximum flood extent envelope for all areas within the catchment can be mapped. The calculated critical durations are shown in Table 5.1.


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Table 5.1: Total and individual catchment critical durations

Main #1

Catchment

Catchment critical duration (hrs)

Total catchment critical duration (hrs)

Drainage model

B1

2.9

10.9

Dalmarnock

B2

5.3

10.9

Dalmarnock

B3

5.9

10.9

Dalmarnock

Trib #1

B6

5.9

10.9

Dalmarnock

Trib #2

B5

3.5

10.9

none

Main #2

B16

6.5

10.9

Dalmarnock

Trib #3

B14ds

4.3

10.9

Dalmuir

B13

5.3

10.9

Dalmuir

B15

6.7

10.9

Dalmuir

B8

3.3

10.9

Dalmuir

Trib #4

B9

5.9

10.9

Dalmuir

B10

6.7

10.9

Dalmuir

Main #3

B7

7.9

10.9

Dalmarnock & Dalmuir

Main #4

B17

7.5

10.9

Dalmarnock & Dalmuir

Main #5

B11

9.3

10.9

Dalmarnock & Dalmuir

Main #6

B18

10.9

10.9

Dalmarnock & Dalmuir

5.2.2 Model Description See Figures 4.3 and 4.4 for an overall view of the Bothlin Burn catchment. The Bothlin burn originates from a spring located to the west of the study area, south of Red Deer village residential park, and flows easterly through agricultural grazing lands to the Gartloch pools, so called as there is a newer emerging permanent pond forming on the easterly side of the B806 Garthloch roadway, underneath which the exiting flows of the primary Garthloch pond get culverted easterly. North Lanarkshire Council have informed AECOM that this road is reportedly periodically flooded due to a combination of a dip in its elevation at this location combined with high pond water levels at particular periods during the year. The Bothlin Burn flow emerges from the Gartloch pools and continues through agricultural land which becomes marshier as it flows into Bishop Loch with a surface area of approximately 23ha.


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Figure 5.1: B806 Garthloch Road

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Figure 5.2: Bishop Loch

Bishop Loch is fed by a further tributary from the south-east which emanates just west of Lochend Road. Flow from the Bishops Loch exits at two outlet points at its north side, one of which is fed into from the east by a tributary which runs through both the Lochend Loch (c.14.1ha) and Woodend Loch (c.20ha). A sharp crested weir is located at the outlet of the Lochend Loch which leads into a tapering concrete channel with sluice gate for effective regulation of the water level in the loch for recreation activities. Figure 5.3: Woodend Loch

Figure 5.4: Sluice Gate at Lochend Loch

The two tributaries of the Bishop Loch outlet points converge further downstream in marshy lands and continue to flow northeasterly towards the M73 motorway. Before the channel reaches the M73, a further Bothlin Burn tributary enters from the west, which arises in the Muirhead area and is contributed to from the north by Johnston Loch (Figure 5.5). This tributary enters a long culvert south of Inverary Drive to the west of Gartcosh (Figure 5.6), and emerges south of the B806 road.


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Figure 5.5: Johnston Loch

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Figure 5.6: Culvert entrance near Inverary Drive

The Bothlin Burn then flows through a culvert under the M73 where it continues westerly, joining with a tributary emanating from the Marnock area, before taking an abrupt turn northwards and is culverted under the railway line (Figure 5.7). The Bothlin Burn channel continues north-east before changing direction north westerly and again is culverted for some 700m under the railway line, the site of the former Gartcosh Steelworks, and Auldyards Road. It flows north east in open channel, is culverted under Johnston Road, before turning west into a culvert beneath the M73. North of the M73, the burn flows north through the Mount Ellen golf club before being culverted under Drumcavel Road (Figure 5.8), and exiting the study boundary. Figure 5.7: Railway culvert

Figure 5.8 Culvert at below Drumcavel Road

The hydraulic model of the Bothlin Burn consisted of cross-sections connected by links, hydraulic structures and lochs. The cross-sections and hydraulic structures were created in RS using topographic survey data. The lochs were modelled using InfoWorks RS storage areas nodes which allowed a polygon to be created over the LiDAR ground model data to create a deptharea relationship.


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In the case of the Bothlin Burn channel downstream of Bishops loch, it was noted that the LiDAR levels indicated ground model levels that were 1 – 1.6m higher than the loch level and similarly for the topographic survey data in the area. For the higher AEP runs, where overtopping of the channel banks was occurring, extrapolating the surveyed cross-sections into the LiDAR data to accommodate the overtopping flows would be unfeasibly inaccurate. This necessitated the removal of the channel cross-sections downstream of Bishops Loch to the confluence point with its tributary to the east, and its replacement with an Infoworks storage area node. The depth-area relationship for the storage area was created using the amended ground model, based on additional spot level survey data in the area, as described in Section 2.2. For the lower AEP scenario’s where channel banks were not being overtopped, the channel cross sections replaced the storage area, see Figure 5.9 for a schematic of the model. Some sections of the Bothlin Burn model required the surveyed cross-sections to be extended into the floodplain. In these locations, the cross-sections were extended manually into the floodplain and the ground model used to generate ground levels (Figure 5.10). In other areas of floodplain where overtopping of the banks occurred, and it was judged that little flow conveyance would occur, inundation of the floodplain was represented using an Infoworks storage area node. The representative channel was connected to the storage area using a lateral spill (Figure 5.11).


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Gartloch and Gartcosh Hydrological Study

Figure 5.9: Bothlin Burn model schematic

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Figure 5.10: Example sections extended into floodplain

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Note for the following model figures the lighter blue shading represents Flood Plains which are linked to Storage areas, the darker blue shaded areas. Flood Plain

Storage Areas


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Figure 5.11: Example floodplain storage area connected by spill units

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5.2.3 Model Inflows Boundary point inflow points to the Bothlin Burn model are illustrated in Figure 4.4. Point inflow boundaries represented inflow from each subcatchment or tributary, and lateral inflows to represent flow from additional catchment area between two modelling points were included. These inflows were distributed along reach based on the length of river channel. Both point and lateral inflows were generated using FEH rainfall runoff boundary nodes in the Infoworks model, the catchment characteristics of which are included in Appendix C.


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Molendinar Burn Model

5.3.1 Model Description The hydrology and flow paths of the Molendinar Burn are described in Section 4.6. As described in this section, the Molendinar Burn flows west through a marshy area east of Loch Road towards Loch Road. Previously, it seems that it would then discharge into Frankfield Loch via a culvert beneath Loch Road. However no sign of this culvert was found during site inspection, and it is through that it may be redundant following raising of Loch Road for the Frankfield Loch Development. A new culvert has been provided at a higher level (Figure 4.7), causing flow to be diverted along a bypass ditch (Figure 4.8) flowing north and discharging into the Garnkirk Burn on the other side of the railway line. At the east side of Frankfield Loch, flow is discharged into the Molendinar Burn and flows through the Strathclyde University playing fields,. A number of structures affect the hydraulics of the channel in this reach, including a culvert with road embankment across the channel, Figure 5.12, wooden footbridge Figure 5.13, and twin culvert road bridge Figure 5.14. The channel in this reach is generally sluggish and weedy, Figure 5.15.

Figure 5.12: Culvert with road embankment

Figure 5.13: Wooden footbridge

Figure 5.14: Twin pipe road bridge

Figure 5.15: Channel through playing fields


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A pumping station is located just upstream of where the watercourse passes beneath Avenue End Road Figure 5.16. Two pumps (duty-standby) pump water from the watercourse into a chamber. Trigger levels at the pump inlet channel turn the pump on when the water level rises above the upper trigger level, and off when the water level drops below the lower trigger level. The chamber discharges into 1m square box culvert, taking flow under the road and into a manhole on the grassy area to the west of the road. From here, flow is piped through an 18� diameter pipe, through a series of manholes located along the walkway towards Hogganfield Loch, before being discharged into the loch Figure 5.17. Figure 5.16: Stepps pumping station

Figure 5.17: Outfall into Hogganfield Loch

The hydraulic model (Figure 5.18) of the Molendinar Burn consisted of channel cross sections connected by links, hydraulic structures and lochs. The cross sections and hydraulic structures were created in RS using topographic survey data. Where necessary, cross sections were extended using the ground model data. Lochs were modelled using InfoWorks RS storage area nodes. The pumping station was modelled using an InfoWorks RS pump node, with pump curve data input from manufacturer’s information, and logical rules to reflect the trigger levels.


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Figure 5.18: Molendinar Burn InfoWorks RS model

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5.3.2 Model Inflows Boundary point inflow points to the Molendinar are illustrated in Figure 4.7. Point inflow boundaries represented inflow from each tributary or subcatchment (Mol_1 and Inter Mol_1-Mol_2), and lateral inflow to represent flow from the additional catchment area between Frankfield and Hogganfield Loch. Both point and lateral inflows were generated using FEH rainfall runoff boundary nodes in the InfoWorks model, the catchment characteristics of which are included in Appendix C. 5.4

Bishop Burn Model

5.4.1 Model Description Bishop Burn flows through the south east corner of the study area, flowing south west from the park before being culverted beneath the Monkland Canal. The upstream extent of the model is at the outlet of this culvert. Continuing south west, the watercourse flows through a short stretch of woodland towards the development off Oakridge Road. A rectangular screened culvert takes the burn beneath Oakridge Road, Figure 5.19. From the culvert outlet, the burn flows down a roughly trapezoidal channel with grassed banks (Figure 5.20) to a second screened culvert beneath Coatbridge Road (Figure 5.21), the boundary of the study area. Downstream of Coatbridge Road, the channel gradient steepens Figure 5.22, and some 350m downstream of the culvert outlet, the watercourse enters another culvert before discharging to the Luggie Burn. The downstream extent of the model is some 100m downstream of the Coatbridge Road culvert outlet.


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Gartloch and Gartcosh Hydrological Study

Figure 5.19: Culvert beneath Oakridge Road

Figure 5.20: Channel between Oakridge and Coatbridge Road

Figure 5.21: Culvert beneath Coatbridge Road

Figure 5.22: Channel downstream of Oakridge Road

36

Again the channel cross sections and hydraulic structures are represented in Infoworks as nodes using information from topographic survey data. Overbank or floodplain areas were represented using ground model data where necessary. Figure 5.23 shows a screen shot of the model.

5.4.2 Model Inflows The Bishop Burn model has simpy one point inflow at the upstream end, representing flow generated by the total catchment down to its confluence with the Luggie Burn (Figure 4.11).


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Figure 5.23: Bishop Burn model screenshot

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5.5 Surface Water Modelling This study encompassed an assessment of the sewerage and drainage systems within the study area to evaluate and their interaction with the wider surface water regime. The existing Scottish Water sewer models were used to review and assess the interaction with the surface water system for the area. The affect of the surface water flow interaction was then included in the hydraulic modelling of the watercourses, ponds and wetlands system within the study area. The study area is covered by three Scottish Water drainage areas, Dalmarnock, Dalmuir and Daldowie; the catchment models for Dalmarnock and Dalmuir were provided by Scottish Water for use in this study. The Daldowie model was not incorporated into the assessment as only a very small area of the site is within the Dalmuir drainage catchment and the surface water drainage impact is negligible.


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The majority of the urban and suburban areas within the study area are drained by combined sewer systems, draining both foul and surface water within the same pipe network. These combines systems effectively remove surface water from the catchment by draining surface water from the urbanised areas and discharging to the River Clyde vial the Dalmarnock, Dalmuir or Daldowie sewer and waste-water treatment systems. These combined systems are considered to remove water from the natural contributing catchments of the study area up to the capacity of the drainage system, drainage systems are generally designed for different rainfall conditions; lower extremity (AEP) and shorted duration rainfall, than is typically considered for hydrological studies or flood protection from natural catchments and watercourses. Where watercourses are wholly represented in the drainage area model, the models where used to evaluate flood levels and the extent of flood inundation. This is only the case where watercourses are extensively culverted and there are significant associated drainage systems. In order to represent the affect of the combined drainage systems within the wider natural catchment, the urban areas were removed from the contributing catchment and hydrology, and replaced with a flow hydrograph to represent the runoff from the urban area which would occur in events where the capacity of the combined drainage system is exceeded. This runoff hydrograph was derived from the results of the catchment sewer and drainage models. 5.5.1 Whamflet Burn and Tolcross Burn (Dalmarnock catchment model) The Whamflet and Tolcross Burns through the study area are explicitly represented within the Dalmarnock catchment model. In order to properly represent overland flow and flood depths during out of bank flood events; flood levels and the extent of inundation were derived from the Dalmarnock catchment model using the two dimensional flow analysis within Infoworks CS 2D incorporating the Digital Terrain Model (DTM). 5.5.2 Bothlin Burn (Dalmarnock and Dalmuir catchment models) Within the southern part of the study area, south of Bishop Loch, parts of the urban areas of Easterhouse which are within the natural catchment of Bishop Loch are drained by the Dalmarnock drainage network which removes surface water from the catchment. The Dalmarnock catchment model was run for the critical durations for the wider catchment and the range of annual exceedance probability events under consideration. Flooding within the catchment model, from rainfall in excess of the capacity of the drainage system, was translated into an inflow hydrograph to represent the expected urban surface water runoff for use within the Gartloch and Gartcosh model. Urban areas in the northern part of the study area, Gartcosh and around Johnston Loch, are drained by the Dalmuir drainage network; this removes surface water from the catchment that would otherwise contribute to natural catchment of the Bothlin Burn. The Dalmuir catchment model was run for the critical durations for the wider catchment and the range of annual exceedance probability events under consideration. Flooding within the catchment model, from rainfall in excess of the capacity of the drainage system, was translated into an inflow hydrograph to represent the expected urban surface water runoff for use within the Gartloch and Gartcosh catchment model. In the Dalmuir drainage catchment there are also two combined sewer overflows (CSOs) within the Gartloch and Gartcosh study area, one immediately south of Gartcosh and another south of Muirhead. These overflows spill to the local watercourse during times when the flow in the drainage system is above the capacity of the downstream system. The spilling flow from these CSOs during the flood events modelled is also taken into account in the Gartloch and Gartcosh modelling. The location of the drainage model inflows and CSO’s are shown in Figure 5.1 (Appendix D). 5.6 Quality Assurance (QA) Checking The Gartloch and Gartcosh models have undergone a series of QA checks throughout the construction process. A number of error trapping procedures have been undertaken to detect obvious errors such as incorrect roughness values, incorrectly specified panel markers, and incorrect link lengths.


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In addition, a series of random spot checks have been undertaken on the modelling of specific structures to check factors such as schematisation, appropriate method, correct interpretation of survey drawings, data input and adequate audit trail. Where deficiencies have been found, other similar structures in the reach have also been checked for similar problems and these corrected as appropriate. The final phase of checking involves the inspection of long and cross-section results to check for any obvious anomalies in the water surface profile. This is a good method of checking for indicators of excessive headlosses at structures, which may indicate that additional bypass spills are required. In addition to this peer checking, Infoworks RS has its own internal validation routine which checks the model data for errors prior to a simulation. Following the validation check, the software highlights any issues to the user in the form of errors, warnings and information messages.


AECOM

Gartloch and Gartcosh Hydrological Study

40


AECOM

6

Gartloch and Gartcosh Hydrological Study

41

Results

6.1 Bothlin Burn Flood Extents Modelled flood extents for 50%, 10%, 3.33%, 2%, 1%, 0.5% and 0.2% AEP events (2, 10, 30, 50, 100, 200 and 500 year return periods) are shown in Figures 6.1 to 6.7. In addition, the effect of climate change on the 0.5% AEP event is shown in Figure 6.8. Model results indicate that during the 50% AEP event (2 year return period), no properties or proposed development areas are at risk of flooding. Main areas of flooding include: • flooding to east and west of Craidendmuir caravan park, between Stepps and Garthamlock, Gartloch Pools; • downstream of Bishop Loch; • upstream of the culvert beneath Gartloch Road, south of Inverary Drive, which extends across the field southwards to Gartloch Road; • between Lochend Loch and Gartcosh Road; • west of Woodend Loch between Gartcosh Road and the M8; • small area of flooding upstream of the culvert beneath Glenboig New Road at Glenboig – this may cause flooding of the road; • upstream and downstream of the railway culvert east of Kingshill Cottages; • and minor out-of-bank flow from downstream of the culvert beneath Gartcosh Industrial Park, to the downstream extent of the model at the A80 Cumbernauld Road. During the 10% AEP event, in addition to these areas, flooding occurs in the marshy area between Gartloch Pools and Bishop Loch, with Gartcosh Road flooding at this location; at Whitehill at the confluence of the branches of the Bothlin Burn flowing from the east and west, upstream of the railway culvert; and Drumcavel Quarry near Mount Ellen Golf Course is inundated. However, no properties appear to be at risk of flooding during this event. Flood extents in the locations above are increased during the modelled 3.33% AEP event, but no properties are at risk of flooding. Flooding of Gartcosh Road near Mid Cottages may occur due to spill from the flooded field between Inverary Drive and Gartcosh Road. A small amount of flooding also begins to occur upstream of the road culvert beneath Lochend Road, south of the Easterhouse North development area. Similarly, during the 2% AEP event (50 year return period), flood extents in these locations are increased. The now extensive flooding of the fields between Inverary Drive and Gartcosh Road puts some properties to the south of Inverary Drive at risk of flooding. There is additional flooding to the north of the Inverary estate, between Johnston Loch and the railway culvert. This flooded area lies to the west of one of the proposed Gartcosh proposed development areas. Flood extents do not increase dramatically for the 1%, 0.5% and 0.2% AEP events, but more properties on Inverary Drive are at risk (approximately 16 properties at the 0.5% AEP event). The most extreme flood extents are predicted for the 0.5% AEP + climate change event. This predicts flood levels of approximately 79.5mAOD in the region of the proposed Gartcosh development, south of Johnston Loch. Flood levels for this event in the region of the proposed private development south of Gartcosh Pools are approximately 77mAOD. Peak flood levels near the Easterhouse North development area are approximately 78.25mAOD. Flood levels to the south of Glenboig development area peak at approximately 82mAOD. A gap in the railway embankment allows flooding to the south of the railway


AECOM

Gartloch and Gartcosh Hydrological Study

42

at this point, and some 2 km downstream, south of the south-west corner of the proposed development, the railway embankment is overtopped, allowing further flooding to the south of the railway. 6.2 Tolcross Burn and Whamflet Burn Flood Extents. Even at the 50% AEP event, flooding occurs at the upstream end of Tolcross Burn at Commonhead. The culvert at this location causes a restriction and results in flooding upstream along the open channel reach between the culvert and Netherhouse Road. This area of flooding lies within the Easterhouse south development area. The Tolcross Burn is also in open channel downstream of the Commonhead culvert outlet, and flooding occurs both between the outlet and Netherhouse Road, and between Netherhouse Road and the M8. However no properties are at risk of flooding. Flood extents do not increase greatly during more severe events, with only small increases in depth. Upstream of the Commonhead culvert, flood levels within the Easterhouse south development during the 0.5% AEP+ climate change event vary from approximately 77.5mAOD to 73.75mAOD. No flooding occurs from the Whamflet Burn during the 50% or 10% AEP events. At the 3.33% AEP event, flooding occurs from the manhole on the verge of the M8 at Easterhouse. The manhole is located some 500m west of the Jimmy Young Bridge at junction 9. 2-D overland flow modelling indicates this may flood a section of the M8, flowing east along the motorway from the manhole and ponding beneath the bridge. At the 0.5% AEP event, depths beneath the bridge exceed 1m. During the 0.5% + climate change and 0.2% AEP events, flooding also occurs from the 2 manholes upstream, causing flooding at Baldinnie Road and Freuchie Street, although no properties are predicted to be affected. 6.3 Molendinar Burn Flood Extents Modelled water levels to the east of Loch Road, even for the most extreme event modelled, are below the level of the new culvert beneath Loch Road, connecting Frankfield Loch with the catchment to the east. Frankfield Loch therefore receives no flow from the catchment to the east, with this flow entirely diverted to the Garnkirk Burn. For the higher flood events, levels in Frankfield Loch are such that the culvert below Loch Road discharges a small amount of flow from Frankfield Loch to the watercourse to the east. Ponding occurs to the east of Loch Road, but no properties are affected. Downstream of Frankfield Loch, pump operation ensures there is negligible out-of-bank flow along the open channel section between Frankfield Loch and the pumping station, even at the most extreme event modelled. No properties are affected. 6.4 Bishop Burn Flood Extents A small amount of overbank flow is predicted along the Bishop Burn, upstream of the culvert below Oakbridge Road, and upstream of the culvert below Coatbridge Road. However, no properties or infrastructure are predicted to be at risk of flooding, and it does not affect any proposed development areas.


AECOM

7

Gartloch and Gartcosh Hydrological Study

43

Summary

This document sets out to establish a baseline of the site to support the design study process by investigating all sources of flooding including fluvial and pluvial flooding under a range of annual exceedance probabilities (AEP). The report provides an assessment of flood risk from the watercourses in the area including a hydrological assessment to define the potential floodplain areas under various annual exceedance probabilities up to 0.1% (500yr return period). An additional allowance to account for estimated future climate change has being assessed for the 3.33% AEP and 0.5% AEP scenarios. The report includes an assessment of the sewerage system in the study area and its interactions with the surface water regime. The results show that no properties are currently at risk of flooding from the Tolcross, Whamflet, Molendinar or Bishop Burns. Approximately 16 properties along Inverary drive, south of Gartcosh, are at risk of flooding from one of the tributaries of the Bothlin Burn. The proposed development at Easterhouse south is affected by flooding from the upstream end of the Tolcross Burn, even at the 50% AEP event, caused by the restriction of the culvert at Commonhead. Flooding from the Whamflet Burn causes ponding of flood water on the M8 motorway, west of the Jimmy Young Bridge. Flood extents from the Bothlin Burn and its tributaries impinge on the boundaries of proposed development areas at Easterhouse north, south of Gartloch Pools, at Gartcosh south of Johnston Loch, and at Glenboig. Predicted flood levels should be taken into account when planning development in these areas. Relevant flood levels indicating the maximum water levels experienced during the 0.5% AEP event plus climate change are given in Table 7.1 below. Table 7.1 – Indicative design flood levels for future development Development location

0.5% + climate change flood level (mAOD)

Easterhouse south

77.5 – 73.75

Easterhouse north

78.25

South of Gartloch Pools

77.0

Gartcosh, south of Johnston Loch

79.5

Glenboig

82.0

7.1 Hydrogeology Although the quality and quantity of information collated in relation to local hydrogeology does not allow a very conclusive assessment, it is not considered likely, that there is significant interaction between local hydrology and underlying groundwaters and minewaters. Any minor interaction would not be significant in terms of the scale of flooding at any location. There is no indication of the disappearance, reappearance, or significant change in size, of surface water features or wetland areas on the historic OS maps reviewed, that could not be attributed to other factors (e.g. the construction of fish ponds and field drains). The limited known mine water discharges onsite and in the vicinity are of insignificant volume. Although it is dangerous to extrapolate, it is considered likely that, if any further mine water discharges were to form, they would be of a similar insignificant magnitude. The age of the mine workings is such that rebound is likely to be complete. It is therefore concluded that mine-water rebound is unlikely to affect surface water in the future.


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Gartloch and Gartcosh Hydrological Study

44

Although data availability is inconsistent both spatially and historically for this study, it is considered unlikely that sufficient additional data would be available to significantly affect these conclusions. The paucity of data, however, means that existing unknown minewater features can’t be categorically ruled out.


AECOM

Appendix A – Site Investigation Reports Reviewed


AECOM


Glasgow File Reference E144 E51 E92 NE1 NE1 NE10 NE11 NE15 NE19

NE20 NE21 NE25 NE26 NE27 NE28 NE29 NE3 NE30

NE35 NE37 NE38 NE39 NE40 NE44

NE45 NE50 NE51 NE52 NE54 NE55 NE56 NE57 NE58 NE60

NE63 NE64 NE65 NE66 NE67 NE71 NE72 NE75 NE76 NE77 NE80 NE81 NE82 NE87

NE90 NE92 NE95 NE97 NE98

Date nr nr nr nr nr

Details of Information

geologic information but no groundwater geologic information but no groundwater 1973 shallow perched groundwater (1973 boreholes) only

nr nr Contains a Hydrogeological report on extracting peat (1989) and information re a proposed opencast coal mine (1986) which also included a water balance (1989). Confirms flooding in the mines. Found sand and gravel deposits below Bishop's loch; indicates leaky aquifer. Did not find a hydraulic connection between Woodend Loch and Bishops loch. 4no pump tests took place which did not show connection between lochs but if the durration was short, might not be expected to (though chemical 1986-1989 composition of water samples supports this). 1980s MossWood. Water near top of sandstone. nr Shaft stabilisation, no groundwater mentioned nr varies drift comprised Made Ground over Glacial Till. Minor seepage(s) only. several site investigations, including the stabilization of an old pit shaft. Perched groundwater nr only. nr 1966 Water table at or near top of rockhead in July 1966; see sheet 2 for details nr Kilgarth Landfill (just offsite to the east, bounded by three railways). Discusses a groundwater resurgance in the study area, at Kingshill Cottages which is a known 1980s to present minewater discharge. Further details on Sheet 5. grouting records. Peat pocket overlying shallow mining in Commonhead. Grouted to circa 46 nr to 66 ft below ground level and consolidated peat. Groundwater pearched only. nr nr nr nr Auchenlee Park. Shaft present. Former quarry was backfilled with generally inert material with very limited/no contamination (hydrocarbon and metal (Cu, Pb, and Zn) 1996-2002 hotspots). Some perched groundwater. nr Perched groundwater, in the form of groundwater strike levels (and no rest) nr Perched groundwater only. nr Mineral positions for several sites in the area nr Regional file regarding mining/stability nr shallow water table or large area of perched groundwater 1960 shallow water table or large area of perched groundwater nr geologic information (drift only) but no groundwater nr sporatic perched groundwater nr logs for suspected shaft in South Rogerfield, Easterhouse. Generally damp but without groundwater strikes. Two positions had heavy water flows (BH4 and BH5, within the 1983 rock, see Sheet 6 for details) nr nr nr nr nr nr

Site investigation included gas monitoring standpipes, but made no mention of groundwater. Site investigation for a housing development. Soune seepages/perched groundwater 1997 in boreholes and trial pits. No monitoring wells noted.

nr nr desk study only, but mentions 2no. 1965 boreholes (1 of which encountered groundwater in 1965 peat at 1.4mbgl). nr text discussing former mining. nr site investigation but groundwater not encountered. 1995 perched groundwater, some monitoring piesometers in 1995. desk study only, but mentions "borehole information within and adjacent to the site indicate depths to groundwater around 1.0 to 2.0m" but no indication of source of this information, unknown borehole locations, date, etc. 1999 site investigation, some water strikes noted. nr geologic information but no groundwater nr north-east of Blackfaulds farm, a few new "sits" noted (subsidance). No investigation logs or nr water information. nr


AECOM

Appendix B – Bothlin Burn FEH statistical estimate


AECOM


CHOICE OF METHOD Site NGR

Bothlin Burn @ B18 269050 669750 Type of Problem/ Objective of Study T-year flow estimates for input to hydraulic model of canal Type of Catchment

y

Statistical Rainfall runoff Hybrid

Type and Availability of Flood Data at subject site at donor sites at analogue sites Other data None Choice of Method Reasons y Preferred Method.

CHOICE OF METHOD WITHIN THE STATISTICAL APPROACH Bothlin Burn @ B18 269050 669750 Method for Estimating QMED Length of record Data transfer from donor/analogue catchment < 2 years From POT data 2 to 13 years As median of annual maxima  > 13 years From catchment descriptors, adjusted by data transfer No gauged record Method for Deriving the Growth Curve Length of gauged record 37 years Target return period T 200 years Site NGR

T <= 27 years Length of Record < T/2 T/2 to T years T to 2T years > 2T years

Site analysis No For confirmation Yes Yes

Pooled analysis1 Yes Yes Yes2 For confirmation2

Shorthand description Pooled analysis Pooled analysis prevails Site & Pooled analysis Site analysis prevails

Pooled analysis1 Yes Yes Yes2 For confirmation2

Shorthand description Pooled analysis Pooled analysis prevails Site & Pooled analysis Site analysis prevails



T >= 27 years Length of Record Site analysis < 14 years No  14 to T years For confirmation T to 2T years Yes > 2T years Yes 1 Size of pooling group chosen to provide 5T station-years of record 2 Subject site excluded from pooled analysis

F:\PROJECTS\Water Resources - Gartloch and Gartcosh FRM & SWMP\Data\Calculations\Catchments\Bothlin subcatchments\ Bothlin Burn @ B18 WINFAP-FEHPROFORMAv3: 03/10/2011

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CATCHMENT DERIVATION F:\PROJECTS\Water Resources - Forth and Clyde Canal Model Development\Data\Calculations\Feeder catchments Bothlin Burn @ B18 Site Name 269050 669750 NGR Auchenguich Location Special Characteristics urbanised CATCHMENT DESCRIPTOR

CD-ROM

ADJUSTED

23.22 1009 0.1365 0.313 39.73 0.871 0.0748 0.58 7.05 36 87 199 0.04 11.52 0.1427 1.496 1.043 8.5 31.7 42.4 988

AREA SAAR FPEXT BFIHOST SPRHOST FARL URBEXT2000 PROPWET DPLBAR DPSBAR ALTBAR ASPBAR ASPVAR LDP FPEXT FPDBAR FPBLOC RMED-1H RMED-1D RMED-2D SAAR4170 SMDBAR RESHOST Adjusted BFI (map) Adjusted SPR

ADJUSTMENT METHOD

REASONS

0.0767

-0.158 vol 3 equ 13.7 0.000 vol 3 Equ 13.25

Urban Extent Calculation

Year URBEXTupdated

2011 0.0767

ESTIMATING QMED FROM CATCHMENT DESCRIPTORS

Station name NGR AREA SAAR BFIHOST SPR FARL URBEXT QMED site rural PRUAF UAF2000 QMED site urban QMED site urban (68% Upper Confidence Limit)

Bothlin Burn @ B18 269050 669750 Catchment Descriptors 23.22 1009 0.313 39.73 0.871 0.0767 3 8.66 m /s Urban Adjustment 1.03 1.079 3 9.35 m /s

3 14.49 m /s

F:\PROJECTS\Water Resources - Gartloch and Gartcosh FRM & SWMP\Data\Calculations\Catchments\Bothlin subcatchments\ Bothlin Burn @ B18 WINFAP-FEHPROFORMAv3: 03/10/2011

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ESTIMATING QMED AT UNGAUGED SITE BY DATA TRANSFER Ungauged site NGR

Bothlin Burn @ B18 269050 669750

Estimate of QMED of Analogues from Catchment Descriptors

Bothlin Burn @ Auchengeich Station Name Station no AREA SAAR BFIHOST SPRHOST FARL URBEXT2000

84023 34.85 1029.00 0.31 39.72 0.91 0.094

Note that if URBEXT is greater than 0.025, donor site should be similarly urbanised in terms of extent, type and layout of urbanisation and have similar urban drainage practices QMEDdonor rural, CD 14.87 Urban Adjustment QMED donor, obs Source of Observed Data

8.67 SEPA - Water Years Adjustment by Data Transfer 0.58 Adjustment 269523 667850 Subject site catchment centroid 268858 668532 Donr site catchment centroid 0.95 Distance 0.79 geographical weighting a QMED adj 5.65 QMED site urban 6.09

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B18 default Station 41028 (Chess Stream @ Chess Bridge) 72014 (Conder @ Galgate) 52015 (Land Yeo @ Wraxall Bridge) 73015 (Keer @ High Keer Weir) 54060 (Potford Brook @ Sandyford Bridge) 203046 (Rathmore Burn @ Rathmore Bridge) 203026 (Glenavy @ Glenavy) 39017 (Ray @ Grendon Underwood) 54052 (Bailey Brook @ Ternhill) 41020 (Bevern Stream @ Clappers Bridge) 33045 (Wittle @ Quidenham) 20002 (West Peffer Burn @ Luffness) 43019 (Shreen Water @ Colesbrook) 206004 (Bessbrook @ Carnbane) 203049 (Clady @ Clady Bridge) Total Weighted means B18 amended 2 Station 72014 (Conder @ Galgate) 203046 (Rathmore Burn @ Rathmore Bridge) 41020 (Bevern Stream @ Clappers Bridge) 33045 (Wittle @ Quidenham) 20002 (West Peffer Burn @ Luffness) 206004 (Bessbrook @ Carnbane) 203049 (Clady @ Clady Bridge) 36009 (Brett @ Cockfield) 33054 (Babingley @ Castle Rising) 48007 (Kennal @ Ponsanooth) 76811 (Dacre Beck @ Dacre Bridge) 29009 (Ancholme @ Toft Newton) 72007 (Brock @ U/s a6) 49003 (de Lank @ de Lank) 48004 (Warleggan @ Trengoffe) Total Weighted means

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DERIVING A POOLED GROWTH CURVE Site NGR

Bothlin Burn @ B18 269050 669750

y

Ungauged site Gauged site

Attached Printouts WINFAP-FEH station details WINFAP-FEH summary information if gauged site Initial Pooling Group Details Name B18 amended 1 Site of interest Bothlin Burn @ B18 Return period of interest 200 years Other information Adjustment/ Changes made to Default Pooling Group. Also note sites that were investigated but retained in the group (i.e. for discordancy) Addition/ Station number Name Reason Deletion/ Move/ Investigate

See pooling group details worksheet Final Pooling Group Details Heterogeneity Measure Strongly heterogeneous Strongly heterogeneous Goodness of Fit Distribution Generalised Logistic Generalised Extreme Value Pearson Type iii Generalised Pareto Growth Curve Fittings WINFAP-FEH growth curve fittings WINFAP-FEH growth curve

H1 H2 Acceptable Fit Y

Attached print outs Name of Pooling Group

Location

1

Scale

Statistical Distribution Selected GL 0.219 Shape

F:\PROJECTS\Water Resources - Gartloch and Gartcosh FRM & SWMP\Data\Calculations\Catchments\Bothlin subcatchments\ Bothlin Burn @ B18 WINFAP-FEHPROFORMAv3: 03/10/2011

-0.147

Page 6 of 9


CONSTRUCTING THE FLOOD FREQUENCY CURVE Site NGR

Bothlin Burn @ B18 269050 669750 

No

URBEXT adjusted from



 URBEXT Updated/Backdated Yes by

Ungauged site Gauged site Year URBEXT adjusted User supplied value of URBEXT

to Method to Estimate QMED

AM POT Catchment descriptors Catchment descriptors and data transfer User defined Urban adjustment applied Y/N

Y QMEDcd QMEDsite adj

3

9.35 m /s 3 6.09 m /s

Flood Frequency Curve WINFAP-FEH flood frequency curve Attached print outs  Comparison with previous analysis Y/N N Details of comparisons Q2 Q5 Q10 Q30 Q50 Q100 Q200 Q500

F:\PROJECTS\Water Resources - Gartloch and Gartcosh FRM & SWMP\Data\Calculations\Catchments\Bothlin subcatchments\ Bothlin Burn @ B18 WINFAP-FEHPROFORMAv3: 03/10/2011

3 6.09 m /s 3 8.22 m /s 3 9.69 m /s 3 12.2 m /s 3 13.5 m /s 3 15.3 m /s 3 17.4 m /s 3 20.5 m /s

Page 8 of 9


F:\PROJECTS\Water Resources - Gartloch and Gartcosh FRM & SWMP\Data\Calculations\Catchments\Bothlin subcatchments\ Bothlin Burn @ B18 WINFAP-FEHPROFORMAv3: 03/10/2011

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AECOM

Appendix C â&#x20AC;&#x201C; Catchment characteristics of subcatchments


AECOM


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type

B1 NS 65850 67250 point

Inflow point Grid ref Inflow type

B1 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

NS 65850 67250 0.52 91 60 0.32 0.312 0.61 36.5 1 0.0769 0.692 0.556 1.19 0.58 8.8 33.6 43.9 990 963 39.7 0.784 0.137 1.421 0.905 0.2077 1.401 -0.015 0.40863 0.35999 0.36736 0.24224 2.31266 -0.015 0.403 0.365 0.365 0.242 2.309

B2 NS 67200 67350 point

Inflow point Grid ref Inflow type

B2 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

NS 67200 67350 2.18 87 60 0.18 0.312 1.6 28.9 1 0.1149 0.824 0.689 3.02 0.58 8.7 33 43.4 994 968 39.7 0.655 0.0879 1.305 0.847 0.1509 1.362 -0.0148 0.40509 0.36683 0.36802 0.24142 2.3026 -0.015 0.403 0.371 0.372 0.242 2.289

B2 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Inter B1-B2 lateral

B1

NS 67200 67350 NS 65850 67250 2.18 0.52 87 91 60 60 0.18 0.32 0.312 0.312 1.6 0.61 28.9 36.5 1 1 0.1149 0.0769 0.824 0.692 0.689 0.556 3.02 1.19 0.58 0.58 8.7 8.8 33 33.6 43.4 43.9 994 990 968 963 39.7 39.7 0.655 0.784 0.0879 0.137 1.305 1.421 0.847 0.905 0.1509 0.2077 1.362 1.401 -0.0148 -0.015 0.40509 0.40863 0.36683 0.35999 0.36802 0.36736 0.24142 0.24224 2.3026 2.31266 -0.015 -0.015 0.403 0.403 0.371 0.365 0.372 0.365 0.242 0.242 2.289 2.309

1.66

1.32 26.52

0.58

995.25 39.70 0.07

0.13 -0.015 0.404 0.369 0.368 0.241 2.299 -0.015 0.403 0.373 0.374 0.242 2.283


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type

B3 NS 67200 67350 point

Inflow point Grid ref Inflow type

B3 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

NS 67200 67350 4.41 86 63 0.18 0.312 2.18 33.5 0.995 0.1343 0.96 0.74 4.45 0.58 8.6 32.4 42.8 982 964 39.7 0.688 0.0657 1.266 0.872 0.098 1.39 -0.01489 0.40145 0.36999 0.37354 0.24142 2.29622 -0.015 0.393 0.377 0.383 0.241 2.288

B3 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Inter B2-B3

Inflow point Grid ref Inflow type

lateral

B2

NS 67200 67350 NS 65850 67250 4.41 2.18 86 87 63 60 0.18 0.18 0.312 0.312 2.18 1.6 33.5 28.9 0.995 1 0.1343 0.1149 0.96 0.824 0.74 0.689 4.45 3.02 0.58 0.58 8.6 8.7 32.4 33 42.8 43.4 982 994 964 968 39.7 39.7 0.688 0.655 0.0657 0.0879 1.266 1.305 0.872 0.847 0.098 0.1509 1.39 1.362 -0.01489 -0.0148 0.40145 0.40509 0.36999 0.36683 0.37354 0.36802 0.24142 0.24142 2.29622 2.3026 -0.015 -0.015 0.393 0.403 0.377 0.371 0.383 0.372 0.241 0.242 2.288 2.289

B6 Grid Ref: 2.23

AREA ALTBAR ASPBAR ASPVAR BFIHOST

1.55 38.00

DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP

0.58

PROPWET RMED-1H RMED-1D RMED-2D

970.27

SAAR SAAR4170

39.70

SPRHOST URBCONC1990

0.044

URBEXT1990 URBLOC1990 URBCONC2000

0.046

URBEXT2000 URBLOC2000

-0.015

C

0.398

D1

0.373

D2

0.379

D3

0.241

E

2.290

F

-0.015

C(1km)

0.383

D1(1km)

0.383

D2(1km)

0.394

D3(1km)

0.240

E(1km)

2.287

F(1km)

B6 NS 68750 66550 point

B5

NS 68750 66550 NS 70050 66150 2.71 1.97 85 85 301 299 0.21 0.26 0.32 0.323 2.1 1.08 29.7 24.5 0.639 0.541 0.2138 0.2839 5.107 6.879 1.22 1.036 3.82 2.32 0.58 0.58 8.5 8.5 31.2 31.2 41.6 41.5 955 956 949 950 39.99 40.08 0.865 0.841 0.0786 0.0418 0.82 1.852 0.968 1 0.085 0.0481 0.833 1.838 -0.01466 -0.01486 0.39465 0.39448 0.3753 0.37564 0.38854 0.38756 0.24102 0.24103 2.27556 2.27455 -0.014 -0.015 0.396 0.392 0.374 0.374 0.392 0.386 0.241 0.241 2.277 2.273

0.74

0.85 43.54

0.58

952.34 39.75 0.18

0.18 -0.014 0.395 0.374 0.391 0.241 2.278 -0.011 0.407 0.374 0.408 0.241 2.288


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type B5 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

B5 NS 68275 66795 point

Inflow point Grid ref Inflow type

B4 NS 68276 66797 point

Grid Ref:

NS 70400 66400 1.17 84 289 0.21 0.312 0.9 28.2 0.572 0.402 11.15 0.865 1.89 0.58 8.5 31.3 41.6 964 959 39.7 0.841 0.0709 1.721 1 0.0816 1.704 -0.01478 0.39558 0.37567 0.38847 0.24106 2.2749 -0.015 0.392 0.374 0.386 0.241 2.273

B4

NS 70050 66150 NS 70400 66400 1.97 1.17 85 84 299 289 0.26 0.21 0.323 0.312 1.08 0.9 24.5 28.2 0.541 0.572 0.2839 0.402 6.879 11.15 1.036 0.865 2.32 1.89 0.58 0.58 8.5 8.5 31.2 31.3 41.5 41.6 956 964 950 959 40.08 39.7 0.841 0.841 0.0418 0.0709 1.852 1.721 1 1 0.0481 0.0816 1.838 1.704 -0.01486 -0.01478 0.39448 0.39558 0.37564 0.37567 0.38756 0.38847 0.24103 0.24106 2.27455 2.2749 -0.015 -0.015 0.392 0.392 0.374 0.374 0.386 0.386 0.241 0.241 2.273 2.273

B4 0.8

AREA ALTBAR ASPBAR ASPVAR BFIHOST

0.88 19.09

DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP

0.58

PROPWET RMED-1H RMED-1D RMED-2D

944.30

SAAR SAAR4170

40.64

SPRHOST URBCONC1990

0.00

URBEXT1990 URBLOC1990 URBCONC2000

0.00

URBEXT2000 URBLOC2000

-0.015

C

0.393

D1

0.376

D2

0.386

D3

0.241

E

2.274

F

-0.015

C(1km)

0.392

D1(1km)

0.374

D2(1km)

0.386

D3(1km)

0.241

E(1km)

2.273

F(1km)


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type B16 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

B6

NS 69100 67000 NS 68750 66550 7.83 2.71 85 85 34 301 0.11 0.21 0.314 0.32 2.69 2.1 33.5 29.7 0.854 0.639 0.1587 0.2138 2.437 5.107 0.995 1.22 5.32 3.82 0.58 0.58 8.6 8.5 31.9 31.2 42.4 41.6 972 955 958 949 39.79 39.99 0.746 0.865 0.0709 0.0786 1.054 0.82 0.914 0.968 0.0877 0.085 1.21 0.833 -0.01475 -0.01466 0.39844 0.39465 0.37246 0.3753 0.38029 0.38854 0.24124 0.24102 2.28787 2.27556 -0.014 -0.014 0.394 0.396 0.378 0.374 0.393 0.392 0.241 0.241 2.283 2.277

B19 NS 68840 66880 point

B3 5.12

2.45 35.51

0.58

981.00 39.68 0.07

0.09 -0.015 0.400 0.371 0.376 0.241 2.294 -0.014 0.393 0.380 0.394 0.241 2.286

NS 68350 66750 4.41 86 63 0.18 0.312 2.18 33.5 0.995 0.1343 0.96 0.74 4.45 0.58 8.6 32.4 42.8 982 964 39.7 0.688 0.0657 1.266 0.872 0.098 1.39 -0.01489 0.40145 0.36999 0.37354 0.24142 2.29622 -0.015 0.393 0.377 0.383 0.241 2.288

2 0.71 km

mAOD

0.83 km 48.00 m/km

0.58 mm mm mm 974.77 mm mm 39.59 % 0.07

0.03 -0.014 0.394 0.377 0.391 0.241 2.283 -0.008 0.393 0.399 0.459 0.241 2.275


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type B7 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

B16

NS 70150 67650 NS 69100 67000 13.45 7.83 85 85 121 34 0.07 0.11 0.313 0.314 3.51 2.69 31.6 33.5 0.799 0.854 0.1597 0.1587 1.944 2.437 0.989 0.995 6.74 5.32 0.58 0.58 8.6 8.6 31.9 31.9 42.5 42.4 991 972 971 958 39.75 39.79 0.688 0.746 0.0723 0.0709 1.078 1.054 0.864 0.914 0.0896 0.0877 1.206 1.21 -0.01448 -0.01475 0.39785 0.39844 0.37578 0.37246 0.3805 0.38029 0.2408 0.24124 2.28691 2.28787 -0.014 -0.014 0.396 0.394 0.374 0.378 0.392 0.393 0.241 0.241 2.283 2.283

Inter B16-B7 lateral

Inflow point Grid ref Inflow type

B13 NS 67300 68200 point

Grid Ref:

NS 67300 68200 0.6 88 133 0.35 0.312 1.07 15.9 1 0.3182 1.492 0.96 1.73 0.58 8.7 33 44.1 1026 987 39.7 0.605 0.2004 0.994 0.831 0.4017 1.061 -0.01445 0.40609 0.37545 0.36704 0.24068 2.29871 -0.014 0.402 0.368 0.373 0.24 2.29

B15 5.62

2.58 28.95

0.58

1017.47 39.69 0.07

0.09 -0.014 0.397 0.380 0.381 0.240 2.286 -0.014 0.399 0.368 0.391 0.241 2.283

NS 69650 67550 4.59 86 162 0.28 0.312 2.37 29.4 0.935 0.1429 0.955 1.053 4.7 0.58 8.5 31.8 42.9 1025 992 39.7 0.622 0.0799 1.19 0.783 0.106 1.357 -0.01412 0.39709 0.38171 0.37843 0.24001 2.28695 -0.014 0.396 0.374 0.392 0.241 2.283

B13 1.03

AREA ALTBAR ASPBAR ASPVAR BFIHOST

1.02 26.96

DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP

0.58

PROPWET RMED-1H RMED-1D RMED-2D

983.92

SAAR SAAR4170

39.67

SPRHOST URBCONC1990

0.05

URBEXT1990 URBLOC1990 URBCONC2000

0.03

URBEXT2000 URBLOC2000

-0.014

C

0.397

D1

0.375

D2

0.391

D3

0.241

E

2.279

F

-0.014

C(1km)

0.411

D1(1km)

0.344

D2(1km)

0.384

D3(1km)

0.241

E(1km)

2.283

F(1km)


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type B15 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

B13

NS 69650 67550 NS 67300 68200 4.59 0.6 86 88 162 133 0.28 0.35 0.312 0.312 2.37 1.07 29.4 15.9 0.935 1 0.1429 0.3182 0.955 1.492 1.053 0.96 4.7 1.73 0.58 0.58 8.5 8.7 31.8 33 42.9 44.1 1025 1026 992 987 39.7 39.7 0.622 0.605 0.0799 0.2004 1.19 0.994 0.783 0.831 0.106 0.4017 1.357 1.061 -0.01412 -0.01445 0.39709 0.40609 0.38171 0.37545 0.37843 0.36704 0.24001 0.24068 2.28695 2.29871 -0.014 -0.014 0.396 0.402 0.374 0.368 0.392 0.373 0.241 0.24 2.283 2.29

Inter B13-B15 lateral

Inflow point Grid ref Inflow type

B14 NS 69500 68300 point

Grid Ref:

NS 69500 68300 0.67 87 181 0.3 0.312 0.56 27.7 0.631 0.1165 0.827 0.85 1.3 0.58 8.4 31.2 42.4 1043 1009 39.7 0.609 0.0865 1.104 0.813 0.1259 1.368 -0.014 0.39202 0.38684 0.38821 0.2399 2.27865 -0.014 0.39 0.387 0.389 0.239 2.281

B14ds 3.99

2.13 31.43

0.58

1024.85 39.70 0.06

0.06 -0.014 0.396 0.383 0.380 0.240 2.285 -0.014 0.395 0.375 0.395 0.241 2.282

NS 68950 67800 1.03 86 181 0.33 0.312 1.06 31.6 0.743 0.1138 0.872 0.908 2.06 0.58 8.4 31.2 42.4 1038 1004 39.7 0.621 0.0751 1.084 0.774 0.1005 1.234 -0.014 0.39178 0.38648 0.38824 0.23972 2.27941 -0.014 0.39 0.387 0.389 0.239 2.281

B14 2.96

AREA ALTBAR ASPBAR ASPVAR BFIHOST

1.81 31.37

DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP

0.58

PROPWET RMED-1H RMED-1D RMED-2D

1020.27

SAAR SAAR4170

39.70

SPRHOST URBCONC1990

0.06

URBEXT1990 URBLOC1990 URBCONC2000

0.05

URBEXT2000 URBLOC2000

-0.014

C

0.397

D1

0.381

D2

0.377

D3

0.240

E

2.287

F

-0.014

C(1km)

0.397

D1(1km)

0.371

D2(1km)

0.397

D3(1km)

0.242

E(1km)

2.282

F(1km)


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type B14ds Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Bothlin Burn subcatchment characterist Inter B14-B14ds lateral

Inflow point Grid ref Inflow type

B14

NS 68950 67800 NS 69500 68300 1.03 0.67 86 87 181 181 0.33 0.3 0.312 0.312 1.06 0.56 31.6 27.7 0.743 0.631 0.1138 0.1165 0.872 0.827 0.908 0.85 2.06 1.3 0.58 0.58 8.4 8.4 31.2 31.2 42.4 42.4 1038 1043 1004 1009 39.7 39.7 0.621 0.609 0.0751 0.0865 1.084 1.104 0.774 0.813 0.1005 0.1259 1.234 1.368 -0.014 -0.014 0.39178 0.39202 0.38648 0.38684 0.38824 0.38821 0.23972 0.2399 2.27941 2.27865 -0.014 -0.014 0.39 0.39 0.387 0.387 0.389 0.389 0.239 0.239 2.281 2.281

B8 NS 69500 68300 point

Inflow point Grid ref Inflow type

B8 Grid Ref: 0.36

AREA ALTBAR ASPBAR ASPVAR BFIHOST

0.57 38.86

DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP

0.58

PROPWET RMED-1H RMED-1D RMED-2D

1028.69

SAAR SAAR4170

39.70

SPRHOST URBCONC1990

0.05

URBEXT1990 URBLOC1990 URBCONC2000

0.05

URBEXT2000 URBLOC2000

-0.014

C

0.391

D1

0.386

D2

0.388

D3

0.239

E

2.281

F

-0.014

C(1km)

0.390

D1(1km)

0.387

D2(1km)

0.389

D3(1km)

0.239

E(1km)

2.281

F(1km)

NS 72800 68700 0.97 103 254 0.54 0.312 0.74 34.4 0.946 0.1179 0.849 0.515 1.65 0.58 8.6 31.9 42.2 1024 1017 39.7 0.5 0.0064 0.246 -999999 0.0026 -999999 -0.014 0.40068 0.38119 0.38388 0.24087 2.28013 -0.014 0.402 0.38 0.384 0.241 2.276

B9 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Inter B8-B9 lateral

B8

NS 71000 67500 NS 72800 68700 4.63 0.97 93 103 239 254 0.25 0.54 0.312 0.312 2.12 0.74 34.3 34.4 0.97 0.946 0.1479 0.1179 0.989 0.849 0.84 0.515 4.23 1.65 0.58 0.58 8.5 8.6 31.7 31.9 42 42.2 1013 1024 1004 1017 39.7 39.7 0.583 0.5 0.0532 0.0064 0.956 0.246 0.731 -999999 0.0543 0.0026 1.145 -999999 -0.01403 -0.014 0.39864 0.40068 0.37956 0.38119 0.38589 0.38388 0.24097 0.24087 2.27753 2.28013 -0.014 -0.014 0.399 0.402 0.379 0.38 0.387 0.384 0.241 0.241 2.277 2.276

Grid Ref: 3.66 AREA ALTBAR ASPBAR ASPVAR BFIHOST 2.04 DPLBAR 34.27 DPSBAR FARL FPEXT FPDBAR FPBLOC LDP 0.58 PROPWET RMED-1H RMED-1D RMED-2D 1010.08 SAAR SAAR4170 39.70 SPRHOST URBCONC1990 0.07 URBEXT1990 URBLOC1990 URBCONC2000 0.07 URBEXT2000 URBLOC2000 -0.014 C 0.398 D1 0.379 D2 0.386 D3 0.241 E 2.277 F -0.014 C(1km) 0.398 D1(1km) 0.379 D2(1km) 0.388 D3(1km) 0.241 E(1km) 2.277 F(1km)


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type B10

Inter B9-B10

Inflow point Grid ref Inflow type

lateral

B9

NS 70250 67600 NS 71000 67500 5.44 4.63 92 93 240 239 0.24 0.25 0.312 0.312 2.62 2.12 32.8 34.3 0.968 0.97 0.1493 0.1479 1.037 0.989 0.871 0.84 5.05 4.23 0.58 0.58 8.5 8.5 31.6 31.7 42 42 1011 1013 1001 1004 39.7 39.7 0.58 0.583 0.0471 0.0532 1.068 0.956 0.747 0.731 0.0487 0.0543 1.207 1.145 -0.01407 -0.01403 0.39836 0.39864 0.37909 0.37956 0.38633 0.38589 0.24098 0.24097 2.27753 2.27753 -0.014 -0.014 0.396 0.399 0.374 0.379 0.392 0.387 0.241 0.241 2.283 2.277

B11ds Grid Ref: 0.81

AREA ALTBAR ASPBAR ASPVAR BFIHOST

0.89 24.23

DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP

0.58

PROPWET RMED-1H RMED-1D RMED-2D

999.57

SAAR SAAR4170

39.70

SPRHOST URBCONC1990

0.01

URBEXT1990 URBLOC1990 URBCONC2000

0.017

URBEXT2000 URBLOC2000

-0.014

C

0.397

D1

0.376

D2

0.389

D3

0.241

E

2.278

F

-0.014

C(1km)

0.379

D1(1km)

0.345

D2(1km)

0.421

D3(1km)

0.241

E(1km)

2.317

F(1km)

B11 NS 70950 68950 point

B11

NS 70950 69000 NS 70950 68950 20.3 19.84 87 87 202 196 0.06 0.05 0.313 0.313 4.83 4.88 33.4 32.7 0.854 0.851 0.1511 0.1516 1.602 1.621 1.006 1.004 8.6 8.55 0.58 0.58 8.5 8.5 31.8 31.8 42.4 42.4 1000 999 982 981 39.73 39.73 0.649 0.652 0.0654 0.0658 1.058 1.053 0.821 0.819 0.0805 0.0811 1.121 1.116 -0.01434 -0.01434 0.39793 0.39793 0.37703 0.37688 0.3826 0.3825 0.24086 0.24085 2.28397 2.28401 -0.014 -0.014 0.398 0.398 0.38 0.38 0.387 0.387 0.241 0.241 2.283 2.283

0.46

0.65 63.59

0.58

1043.13 39.73 0.05

0.05 -0.014 0.398 0.383 0.387 0.241 2.282 -0.014 0.398 0.380 0.387 0.241 2.283


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type B11 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Inter B17-B11 lateral

Inflow point Grid ref Inflow type

B12 NS 69800 69450 Point

Grid Ref:

NS 69800 69450 0.93 90 57 0.2 0.312 1.05 41 1 0.0568 0.324 0.81 1.81 0.58 8.4 31.2 42.7 1062 1018 39.7 0.739 0.0541 1.42 0.571 0.0324 1.444 -0.014 0.39302 0.39302 0.38032 0.23941 2.27833 -0.014 0.39 0.392 0.39 0.24 2.274

B17

NS 70950 68950 NS 70200 67650 19.84 18.91 87 87 196 196 0.05 0.06 0.313 0.313 4.88 3.3 32.7 32 0.851 0.844 0.1516 0.1566 1.621 1.682 1.004 0.968 8.55 6.79 0.58 0.58 8.5 8.5 31.8 31.8 42.4 42.4 999 997 981 980 39.73 39.74 0.652 0.662 0.0658 0.065 1.053 1.098 0.819 0.841 0.0811 0.0778 1.116 1.238 -0.01434 -0.01436 0.39793 0.398 0.37688 0.37673 0.3825 0.38219 0.24085 0.24085 2.28401 2.2842 -0.014 -0.014 0.398 0.396 0.38 0.374 0.387 0.392 0.241 0.241 2.283 2.283

B12 0.93

AREA ALTBAR ASPBAR ASPVAR BFIHOST

0.96 46.93

DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP

0.58

PROPWET RMED-1H RMED-1D RMED-2D

1039.67

SAAR SAAR4170

39.53

SPRHOST URBCONC1990

0.08

URBEXT1990 URBLOC1990 URBCONC2000

0.148

URBEXT2000 URBLOC2000

-0.014

C

0.397

D1

0.380

D2

0.389

D3

0.241

E

2.280

F

-0.014

C(1km)

0.439

D1(1km)

0.502

D2(1km)

0.285

D3(1km)

0.241

E(1km)

2.283

F(1km)


Bothlin Burn subcatchment characteristics Inflow point Grid ref Inflow type B18 Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

B11ds

NS 69050 69750 NS 70950 69000 23.22 20.3 87 87 199 202 0.04 0.06 0.313 0.313 7.05 4.83 36 33.4 0.871 0.854 0.1427 0.1511 1.496 1.602 1.043 1.006 11.52 8.6 0.58 0.58 8.5 8.5 31.7 31.8 42.4 42.4 1009 1000 988 982 39.73 39.73 0.652 0.649 0.0611 0.0654 1.088 1.058 0.814 0.821 0.0748 0.0805 1.131 1.121 -0.0143 -0.01434 0.39736 0.39793 0.37923 0.37703 0.38266 0.3826 0.24078 0.24086 2.28312 2.28397 -0.014 -0.014 0.4 0.398 0.393 0.38 0.37 0.387 0.24 0.241 2.282 2.283

Inter B11-B18 lateral

B12 2.92

1.80 54.08

0.58

1071.57 39.73 0.03

0.035 -0.014 0.393 0.395 0.383 0.240 2.277 -0.014 0.414 0.483 0.252 0.233 2.275

NS 69800 69450 0.93 90 57 0.2 0.312 1.05 41 1 0.0568 0.324 0.81 1.81 0.58 8.4 31.2 42.7 1062 1018 39.7 0.739 0.0541 1.42 0.571 0.0324 1.444 -0.014 0.39302 0.39302 0.38032 0.23941 2.27833 -0.014 0.39 0.392 0.39 0.24 2.274

1.99

1.46 60.19

0.58

1076.04 39.74 0.02

0.04 -0.014 0.394 0.395 0.384 0.241 2.277 -0.014 0.425 0.526 0.187 0.230 2.276


Molendinar Burn subcatchment characteristics Inflow point Grid ref Inflow type Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Mol_1

Inflow point Grid ref Inflow type

point Mol_1 NS 67200 67350 0.58 88 310 0.34 0.31 0.66 13.40 1 0.2294 1.113 0.744 1.54 0.58 8.8 33.6 44.6 1010.00 975 39.70 0.574 0.15 1.129 0.750 0.08 1.573 -0.015 0.410 0.371 0.364 0.241 2.306 -0.015 0.410 0.376 0.362 0.241 2.303

Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Inter Mol_1-Mol_2 Point

Mol_2 Mol_1 NS 65300 67700 NS 67200 67350 0.72 88 309 0.28 0.31 0.83 14.20 1 0.2457 1.221 0.784 1.85 0.58 8.9 33.6 44.5 1008.00 973 39.70 0.59 0.14 1.140 0.773 0.07 1.516 -0.015 0.410 0.369 0.364 0.241 2.307 -0.014 0.412 0.356 0.365 0.241 2.315

0.58 88 310 0.34 0.312 0.66 13.4 1 0.2294 1.113 0.744 1.54 0.58 8.8 33.6 44.6 1010 975 39.7 0.574 0.1515 1.129 0.75 0.0758 1.573 -0.01481 0.40957 0.37085 0.36439 0.24106 2.30566 -0.015 0.41 0.376 0.362 0.241 2.303

Inflow point Grid ref Inflow type

0.14

0.34 17.51

0.58

999.71 39.70 0.11

0.03 -0.015 0.411 0.362 0.365 0.241 2.312 -0.010 0.420 0.273 0.377 0.241 2.365

Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Inter Mol_2-Mol_3 Lateral

Mol_3 Mol_2 NS 64500 67450 NS 65300 67700 1.3 89 234 0.12 0.31 1.26 20.50 1 0.2096 1.146 0.935 2.76 0.58 8.9 33.8 44.4 1006.00 971 39.70 0.758 0.18 1.014 0.851 0.11 1.006 -0.015 0.410 0.363 0.366 0.241 2.313 -0.015 0.412 0.355 0.370 0.243 2.316

0.72 88 309 0.28 0.312 0.83 14.2 1 0.2457 1.221 0.784 1.85 0.58 8.9 33.6 44.5 1008 973 39.7 0.59 0.1436 1.14 0.773 0.0675 1.516 -0.01476 0.40979 0.3691 0.36448 0.24111 2.30681 -0.014 0.412 0.356 0.365 0.241 2.315

0.58

0.74 28.32

0.58

1003.52 39.70 0.22

0.17 -0.014 0.411 0.355 0.367 0.242 2.320 -0.016 0.412 0.354 0.376 0.245 2.317


Molendinar Burn subcatchment characteristics Inflow point Grid ref Inflow type Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Inter Mol_2-Mol_3 Point

Mol_4 Mol_3 NS 63850 67200 NS 64500 67450 2.34 89 277 0.22 0.31 1.46 21.90 1 0.1455 0.741 1.175 3.51 0.58 9 33.9 44.2 1000.00 970 39.70 0.692 0.13 1.187 0.818 0.09 1.155 -0.015 0.410 0.357 0.369 0.242 2.319 -0.015 0.408 0.346 0.375 0.244 2.335

1.3 89 234 0.12 0.312 1.26 20.5 1 0.2096 1.146 0.935 2.76 0.58 8.9 33.8 44.4 1006 971 39.7 0.758 0.1779 1.014 0.851 0.1135 1.006 -0.01462 0.41013 0.36297 0.36565 0.24136 2.31257 -0.015 0.412 0.355 0.37 0.243 2.316

1.04

1.02 23.65

0.58

992.50 39.70 0.07

0.07 -0.015 0.409 0.350 0.372 0.243 2.327 -0.015 0.403 0.335 0.381 0.245 2.359

Tolcross Burn subcatchment characteristics

Bishop Burn subcatchment characteristics

Inflow point Grid ref Inflow type

Inflow point Grid ref Inflow type

B_1

Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

NS 70700 64200 1.66 82 207 0.4 0.354 1.53 37.7 1 0.0964 0.699 0.839 2.88 0.58 8.5 30.9 41.3 923 910 41.24 0.613 0.0309 1.004 1 0.009 1.352 -0.01431 0.3912 0.37644 0.38421 0.23925 2.27733 -0.014 0.39 0.377 0.385 0.238 2.276

Grid Ref: AREA ALTBAR ASPBAR ASPVAR BFIHOST DPLBAR DPSBAR FARL FPEXT FPDBAR FPBLOC LDP PROPWET RMED-1H RMED-1D RMED-2D SAAR SAAR4170 SPRHOST URBCONC1990 URBEXT1990 URBLOC1990 URBCONC2000 URBEXT2000 URBLOC2000 C D1 D2 D3 E F C(1km) D1(1km) D2(1km) D3(1km) E(1km) F(1km)

Tolcross_us point Mol_1 NS 68100 64950 2.7 79 209 0.2 0.37 2.04 39.70 1 0.1027 0.834 1.028 3.62 0.58 8.5 31 41.4 931.00 915 41.90 0.705 0.10 0.820 0.826 0.12 0.871 -0.014 0.391 0.373 0.384 0.239 2.279 -0.014 0.396 0.373 0.391 0.238 2.282

point B_1


AECOM

Appendix D â&#x20AC;&#x201C; Figures Figures are available on request from: Scott Ferguson Glasgow and Clyde Valley Green Network Partnership 0141 229 7746

Gartloch Gartcosh - Hydrological Study  

Described the hydrological model developed for the Gartloch Gartcosh area, and examins flood extents under a range of scenarios.