Surface Water Assessment for the Gamma-Kappa Power Line Environmental Screening Study

REPORT

Client: MDT Environmental

Reference: MD4703-RHD-ZZ-XX-RP-Z-0001 Status: S0/D02 Date: 9/23/2020

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ROYAL HASKONINGDHV (PTY) LTD

21 Woodlands Drive Building 5 Country Club Estate Woodmead

Johannesburg 2191 Transport & Planning Reg No. 1966/001916/07

+27 87 352 1500 T +27 11 798 6005 F [email protected] E royalhaskoningdhv.com W

Document title: Surface Water Assessment for the Gamma-Kappa Power Line Environmental Screening Study Document short title: Gamma-Kappa Surface Water Reference: MD4703-RHD-ZZ-XX-RP-Z-0001 Status: D02/S0 Date: 9/23/2020 Project name: Environmental Screening Study for the Proposed Development of the Gamma-

Kappa Power Line Project number: MD4703 Author(s): Paul da Cruz

Drafted by: Paul da Cruz

Checked by:

Date:

Approved by:

Date:

Classification Project related

Unless otherwise agreed with the Client, no part of this document may be reproduced or made public or used for any purpose other than that for which the document was produced. Royal HaskoningDHV (Pty) Ltd accepts no responsibility or liability whatsoever for this document other than towards the Client.Please note: this document contains personal data of employees of Royal HaskoningDHV (Pty) Ltd. Before publication or any other way of disclosing, this report needs to be anonymized.

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Table of Contents

1 Introduction 7 1.1 Aims of the Study 7 1.2 Assumptions and Limitations 8 1.3 Site Location and Description 8 1.4 Expertise of the author to compile this specialist assessment 9 1.5 Adherence to Appendix 6 of the EIA Regulations 12 1.6 Definition of Surface Water Features, Wetlands and Hydric Soils 14 1.6.1 Definition of Surface Water Features 14 1.6.2 Definition of Wetlands 15 1.6.3 Definition of Riparian Zones 16

2 Legislative Context 18 2.1 The National Water Act 18 2.2 The National Water Act and Riparian Areas 19 2.3 International Policy Framework and Guidelines 20 2.3.1 The World Bank Policies 20 2.3.2 The International Finance Corporation (IFC) Performance Standards 20 2.3.3 Equator Principles 21

3 Methodology for Assessment 22 3.1 Field Assessment and Riparian Zone Delineation 22 3.2 Prioritisation of Riparian Areas 22 3.3 Identification of Surface Water and Riparian Zone Impacts and Mitigation Measures 23

4 Findings of Assessment 23 4.1 Macro-Drainage Context 23 4.2 Surface Water Typology and Occurrence 28 4.2.1 Riparian Zones 29 4.2.2 Wetland Occurrence 30 4.2.3 Riparian Zone Delineation 31 4.3 Freshwater Hydrology 43 4.4 Groundwater-surface water interactions and implication for riparian zone delineation 48 4.5 Fluvial Morphology 50 4.5.1 Vegetation Composition and Lateral Zonation 55 4.6 Water Quality 60

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5 Freshwater Prioritisation 61

6 Impacts and Mitigation associated with the proposed power line 66 6.1 Impacts associated with placing towers within a surface water feature 66 6.2 Potential Impacts of the construction and operation of the Proposed Power Line on Surface Water Features in the Study Area 67 6.3 Impacts of power line servitude clearing on Riparian Zones 67 6.3.1 Potential Impacts specific to priority riparian areas in the study area 68 6.4 Mitigation Measures 71 6.4.1 General Mitigation Measures related to surface water features and riparian zones 71 6.4.2 Recommended Walk Down 71 6.4.3 Alien Invasive Plant Management within servitudes during operation 72 6.4.4 Recommended areas within corridors in which the proposed power line should not be routed 72 6.5 Impact Rating Matrix 84

7 Water Use Authorisation Implications 86

8 Comparative Assessment of Corridors 87

9 Conclusions and Recommendations 89

10 References 90

Table of Tables

Table 1 – Findings of Compliance with Appendix 6 of the EIA Regulations 12 Table 2 – Tiered classification for aquatic environments in the study area 28 Table 3 – Comparative Assessment of Corridors in the South-western part of the Study Areas 87 Table 4 – Comparative Assessment of Corridors1&2 in the remainder of the Study Areas 88

Table of Figures

Figure 1 – Locality 9 Figure 2 - Schematic diagram indicating the three zones within a riparian area relative to geomorphic diversity (Kleynhans et al, 2007) 17 Figure 3 – Drainage and Quarternary Catchments in the South-western Part of the Study Area 25 Figure 4 - Drainage and Quarternary Catchments in the Central of the Study Area 26 Figure 5 - Drainage and Quarternary Catchments in the North-eastern Part of the Study Area 27 Figure 6 – Riparian Areas in the Study Area – Groot River Area 32 Figure 7 - Riparian Areas in the Study Area – Muishond River Area 33

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Figure 8 - Riparian Areas in the Study Area – Koornplaas Area 34 Figure 9 - Riparian Areas in the Study Area – Vanwyksberg Area 35 Figure 10 - Riparian Areas in the Study Area – Merweville Area 36 Figure 11 - Riparian Areas in the Study Area – Leeu Gamka Area 37 Figure 12 - Riparian Areas in the Study Area – Leeurivier Area 38 Figure 13 - Riparian Areas in the Study Area – Beaufort West Area 39 Figure 14 - Riparian Areas in the Study Area – Rhernosterkop Area 40 Figure 15 - Riparian Areas in the Study Area – Three Sisters Area 41 Figure 16 - Riparian Areas in the Study Area – Gamma Substation Area 42 Figure 17 – Flow along the Sout River within Corridor 1 in June 2013 44 Figure 18 - Example of emergence of surface flow over bedrock outcropping from gravelly substrate and subsequent ‘disappearance’ in a tributary watercourse of the Buffels River in the Spitskop area (Corridors 1&1A)’ 45 Figure 19 - Pools along the Waaikraal River at Kranskraal (Corridor 1) 46 Figure 20 - Flood wrack trapped behind a Vachellia karroo shrub 47 Figure 21 - Extensive salt precipitate along the Brak River (Corridor 1) 48 Figure 22 - Hypothetical cross-section of landscape showing the fractured sandstone aquifer of the Table Mountain Group overlying the fractured shales and groundwater discharges controlled by faults and by geological contacts (le Maitre et al, 2009) 49 Figure 23 - Wide sandy channel bed of the Waaikraal River in Corridor 2 51 Figure 24 - Alluvial deposits adjacent to the primary channel along the upper reaches of the Buffels River in Corridor 1 with a secondary lateral flow channel in the right of the picture 52 Figure 25 – The Knoffelskloof River near the Spitskop Farm in Corridors 1&1A, displaying little or no riparian corridor due to the presence of rocky strata on the edge of the channel 53 Figure 26 - Channel on the outer edge of the Leeu River riparian corridor near Volmoed (Corridor 1). Although located far away from the primary channel, this is arguably part of the lower zone 54 Figure 27 – Elevated view of the Leeu River riparian zone in Corridor 1 showing Salsola- dominated alluvial flats with Vachellia karroo woodland closer to the channel 56 Figure 28 - Stipagrostis namaquensis along a secondary channel 58 Figure 29 - Dense Vachellia karroo thickets and luxuriant understorey within the Platdorings River riparian corridor in Corridor 2 59 Figure 30 - Atriplex nummularia and Prosopis within the Gamka River riparian zone near Steynskraal 60 Figure 31 - Sensitive Surface Water Sites in the South-western Part of the Study Area 63 Figure 32 - Sensitive Surface Water Sites in the Central Part of the Study Area 64 Figure 33 – Sensitive Surface Water Sites in the North-eastern Part of the Study Area 65 Figure 34 - Existing power line servitude within the riparian corridor of the Sout River in Corridor 1 cleared of all herbaceous vegetation 69

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Figure 35 - Power line servitude within the riparian corridor of the Sout River in Corridor 1 cleared of most vegetation with extensive bare areas 70 Figure 36 – Parts of the Corridors to be avoided – Map 1 73 Figure 37 - Parts of the Corridors to be avoided – Map 2 74 Figure 38 - Parts of the Corridors to be avoided – Map 3 75 Figure 39 - Parts of the Corridors to be avoided – Map 4 76 Figure 40 - Parts of the Corridors to be avoided – Map 5 77 Figure 41 - Parts of the Corridors to be avoided – Map 6 78 Figure 42 - Parts of the Corridors to be avoided – Map 7 79 Figure 43 - Parts of the Corridors to be avoided – Map 8 80 Figure 44 - Parts of the Corridors to be avoided – Map 9 81 Figure 45 Parts of the Corridors to be avoided – Map 10 82 Figure 46 - Parts of the Corridors to be avoided – Map 11 83

Appendices

Appendix 1 - Impact Rating Methodology Appendix 2 - CV of Author

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Executive Summary

MDT Environmental Consultants have appointed Royal HaskoningDHV on behalf of Eskom Holdings Ltd. to update a surface water assessment study for the proposed development of 765kV transmission power lines in the Karoo districts of the Western and Northern Cape between Touws Rivier and Three Sisters.(the Gamma-Kappa Project).Eskom has previously undertaken Environmental Impact Assessment (EIA) studies for the proposed development of the Gamma-Kappa Power line Project, but these EIA processes were terminated. Royal HaskoningDHV completed the first draft of the EIA surface water report in 2013, and a subsequent updated draft of the report in 2017 Eskom are currently undertaking an environmental screening study to determine the feasibility of developing a power line along the route and have amended the original corridors of the power line. Accordingly the EIA-phase surface water study is being updated for the screening study.

Study Area Location The Study Area is located within the interior of the Western Cape Province (and a small area of the Northern Cape Province) within the wider region known as the Great Karoo. The proposed corridor alternatives are extensively long and cover a large area; from an area close to the Northern Cape / Western Cape border north-east of Three Sisters in the north-east to the town of Touws Rivier in the south-west, passing close to the Karoo towns of Beaufort West, Leeu-Gamka, Merweville and Laingsburg.

Figure i – Study Area

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Surface Water Typology and Characteristics In the context of the study area, surface water features largely occur in valley floors or on wide plains (typical of large parts of the Great Karoo) where depositional processes predominate. Drainage in these settings is typically expressed as rivers / watercourses with defined riparian zones. However a number of much smaller, first order watercourses do occur in other, sloping terrain settings in the study area.

The nature of drainage typically depends on the nature of the topography; areas of more incised topography with a highly rocky substrate were generally observed to have a high drainage density (i.e. dense drainage), with a lot of small drainage features. These tend to occur high up within catchments, as first order streams that combine to form larger, more distinct drainage features downstream. Areas of flat topography with a sandier substrate were observed to be poorly drained, with a low drainage density. In certain areas drainage emanating from hilly rocky upland areas was noted to ‘disappear’ or dissipate as it flowed into areas of flatter topography.

The low overall levels of precipitation across the study area and strong episodic nature of rainfall has had a strong formative effect on the hydrology of the study area. Most rivers / watercourses are ephemeral or episodic in nature, i.e. only experiencing surface flow (if any) as a response to rainfall events, with flow typically occurring for a short amount of time. Very few rivers were noted to be characterised by flow during the various site visits conducted. Certain other river displayed residual pools; importantly, these residual pools were mostly noted where outcropping of bedrock occurred.

In spite of the presence or absence of surface water the nature of surface water flows in most of the river systems sampled in the area is indicated by the presence of flood wrack, as evidence of significant (surface) flow events within the riverine systems. In certain of the river systems sampled wrack was found at significant heights above the channel bed; a flood event of this volume would inundate an area relatively far beyond the channel, which accords with the presence of alluvial material deposited in these areas.

There is a strong interrelationship between groundwater and surface water in the rivers of this semi-arid area, with groundwater occurring in shallow alluvial aquifers that are hydrologically connected to the channels of the rivers. In many of the rivers sampled, deposits of alluvial material were noted, often taking up a large portion of the cross sectional profile of the riparian corridors. The net accumulation of sediment from catchments in the areas of alluvial deposition along drainage lines and rivers is likely to have altered (increased) the groundwater-holding capacity of these systems, while possibly affecting surface water flows (le Maitre et al, 2009). This process of transmission of surface flow to shallow aquifers is important not only in its obvious effect on surface flow reduction, but also as a source of groundwater recharge to underlying alluvial aquifers. Due to the prevalence of alluvial sediment along most of the rivers in the study area, transmission of surface water (overland flows) into these river systems into the underlying alluvial sediment is expected to be extensive, being a strong factor in the presence of vegetation communities along these rivers that are supported by shallow groundwater. There usually is also a marked change in the vegetation composition and structure in areas where surface and groundwater accumulate.

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Surface Water Morphology Most of the surface water drainage features are watercourses / drainage lines, with a defined channel. In spite of the irregularity of flow, fluvial processes do occur that shape the channel of the drainage feature. The depth, width, and relative location of the channel differed amongst all of the rivers assessed in the field.

Areas adjacent to the active channel typically consisted of fine silty alluvial material, deposited by higher spate flows in the river. Along many of the river reaches assessed in the field, secondary, lateral channels were present immediately adjacent to the primary channel, at a slightly higher level. These secondary lateral channels were noted to be typically shallow (<0.5m deep), narrow features. In spite of being within the zone of most active hydrological activation by flows within the river, these secondary lateral channels were noted to be generally stable and well vegetated.

Along most of the larger river systems, alluvial terraces were noted to exist adjacent to the primary channel. These alluvial terraces consisted of fine silty substrate deposited in situ by fluvial action during large scale flood events. These alluvial terraces often occurred as extensive wide features within the larger river systems such as the Leeu, Gamka and Groot Rivers, in some cases extending to the outer edge of the riparian zone. Where these extensive alluvial flats were found, these displayed characteristics of river floodplains, being characterised by relatively unconsolidated sediment, shaped by wind and water action to display undulating ‘micro-terrain’ in the form of low mounds and depressions. These areas were largely vegetated, with vegetation cover largely consisting of the salt-tolerant succulent shrub Salsola aphylla occurring in varying densities from a dense coverage to a much sparser coverage.

Vegetative Characteristics Vegetation associated with surface water features in the Great Karoo region of the Western Cape differs greatly in composition and structure from the surrounding Karoo Shrubveld vegetation. Riparian zones support distinctive vegetation that differs in structure and function from adjacent terrestrial ecosystems. This marked change in the vegetation composition and structure is an indication of the presence of the accumulation of both surface and groundwater (le Maitre et al, 2009). This difference is expressed in the presence of two distinct vegetation types that occur within the study area and which are largely associated with the larger river systems.

The most commonly occurring and dominant tree / shrub species in this part of the riparian corridor is Vachellia karroo. There are a few other tree and shrub species that were noted to occur along channel banks and margins. The beds of larger channels where alluvial material (gravel and larger cobbles) were typically not vegetated and only in a few cases was the reed Phragmites australis noted to extensively cover the channel bed.

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part of the riparian zone, protecting it from erosion by wind and water, and also providing ‘surface roughness’ that assists in the trapping of sediment.

Away from the active channel, alluvial terraces or flats were noted to occur in most riparian settings. The dominant plant in this setting was the succulent shrub Salsola aphylla, sometimes occurring in high densities across these areas. This plant is tolerant of brackish soils and it is likely that this dominance reflects the presence of saline soils on these alluvial terraces.

Along the larger river corridors, riparian woodlands occupy a significant portion of the riparian zones. The species present within these woodlands (i.e. Vachellia, Searsia, Lycium and other genera) are more typical of savannah but are able to persist by tapping the alluvial and groundwater stores. It is notable that these ‘woodland’ habitats can occur well away from the area of most active hydrological activation, and that Vachellia karroo specimens of significant height (≥5m) can occur in these areas that are distant from the channel, forming a dense impenetrable thicket in places. The presence of woodland of such height and thickness is indicative of the presence of subterranean moisture availability in these alluvial flats. In such woodlands a grassy substrate was often present. Such woodlands were present along some of the larger river systems that are characterised by wide riparian corridors including the Gamka, Leeu, and Sout Rivers.

Riparian Zone Characteristics and Delineation The riparian zone as is commonly found along most rivers and drainage systems in the study area is arguably the most important aspect of surface water features, as it contains vegetation of composition and structure that is not found in non-riverine habitats. It is also the feature of surface water features that is most likely to be impacted by the proposed power line. Hence this report has focussed on riparian corridors in the study area – their characteristics and how these are likely to be impacted.

Riparian zones were delineated based not only on hydromorphological factors, such as channel structure and areas of surface water-related hydrological activation but also based on the presence of vegetation of differing composition and structure to the surrounding Karoo Shrubveld, and thus the presence of alluvial groundwater supply. In many of the larger river systems, the presence of areas of woodland is unlikely to be present due to surface water flooding due to the dry nature of the climate. However such woodland is always associated with a watercourse (even though distant from the main channel in certain cases), and the close interrelationship between surface water and groundwater has been explored above. These areas thus cannot be divorced from the more classically defined riparian zone alongside channels, and as such have been included in the areas delineated as part of the riparian zone.

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Freshwater Prioritisation A number of GIS-based biodiversity and EcoStatus layers (shapefiles) were used to identify priority rivers and riparian areas in the study area. Freshwater features (including riparian areas) that were located within at least two of the designations were labelled as priority areas. Such priority areas can be considered as sensitive areas that should ideally be avoided by the proposed power line.

In order to provide an additional measure of sensitivity, particularly in the context of the potential impact of a power line on riparian woodland, riparian areas displaying the following characteristics were prioritised (and thus identified as areas to be avoided):

◼ the riparian zone is of a width / size that entails that the area is not able to be singly spanned by the proposed power line, thus resulting in towers having to be placed within the riparian zone.

◼ The riparian zone contains a significant area of riparian thickets consisting of trees of greater height than 4m, entailing that these trees would need to be felled if within the power line servitude, resulting in impacts of greater intensity to the riparian zone

Impacts and Mitigation Transmission power lines are not typically associated with impacts on surface water resources within non- woody environments, as the power lines do not have a physical footprint over the length of the power line other than the footprint of each tower position. As the lines are strung above the ground and as the towers are spread approximately 400m apart, most wetlands and rivers are able to be ‘spanned’ by the power lines and thus avoided from being physically affected. Power lines can however be associated with impacts on surface water resources if the towers are placed within a river or wetland, or in wooded settings if they cross the riparian zone of a surface water feature (most relevant in this context). The process of constructing the power line can also cause impacts on surface water resources, especially if certain mitigation measures and procedures are not followed

If towers are constructed within a surface water feature, this activity could potentially adversely affect the soil and vegetation through the compaction of damp soils, the trampling, smothering or removal of vegetation within the surface water feature and the resultant exposure of soils that could result in their desiccation and subsequent erosion. The presence of concrete, as well as machinery which may leak fuel into the surface water feature could result in the introduction of pollutants into the feature. The movement of heavy construction machinery into the surface water feature, especially wetlands and areas of alluvial soils, could result in the alteration of the sub-surface hydrology by creating conduits for the movement of water in the wetland

The most significant potential impact relates to the clearing of a strip of vegetation under the lines. A strip of vegetation is typically cleared under a power line in order to maintain the minimum degree of clearance between the top of the vegetation and the lines. In addition vegetation is also often cleared in the servitude to reduce the risk of a fire that could occur within the power line servitude from creating large amounts of smoke which could create a flashover that could disrupt the flow / supply of electricity along the line.

There is an important distinction that needs to be made between the clearing of woody and other vegetation above a certain clearance (thus retaining the vegetation below the clearance height) and the practice of clearing a strip of land under the lines of all vegetation. The latter practice of clearing of all vegetation constitutes a particularly important impact in the context of the riparian zones which occur along most of the rivers, and smaller drainage lines in the study area as it impacts negatively on the structural integrity of the riparian zone, as it alters the vegetative composition of the servitude, and exposes the understorey that is dependent to a large degree on the shade created by the canopy to the sun. Erosion may result from the clearing of vegetation and die off of roots that bind the soil, thus potentially resulting in the inundation of

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downstream reaches with sediment causing the impairing of filtering functions associated with the riparian zone.

A number of mitigation measures have been specified:

◼ No towers must be placed within the boundaries of any riparian zone of any watercourse that is able to be singly spanned.

◼ Clearing of riparian vegetation should be limited as far as possible. Clearing / felling of woody vegetation should be limited to trees / shrubs above the maximum permitted clearance height, and the understory should not be cleared.

◼ Where surface water is encountered within rivers or watercourses, this should not be utilised for abstraction, or washing of equipment, etc.

◼ No temporary roads or construction accesses must be constructed through any surface water feature.

◼ The vehicle access line along the power line should attempt to utilise existing crossings of the river / watercourse crossed where possible, even if these are distant from the alignment. Such crossings may need to be upgraded. River crossings should be avoided where necessary. If a vehicle access crossing is deemed a technical necessity, the vehicle access crossing of the affected freshwater / surface water feature will need to be fully assessed as part of the Water Use Authorisation process and the impacts of the crossing on the affected reach fully assessed. A set of crossing-specific mitigation measures must be determined by a qualified surface water specialist in this context.

◼ A pre-construction walkdown must occur to assess final tower positions

◼ Alien Invasive plant management must occur in the power line servitude during operation of the line.

◼ Impacts on riparian zones and on freshwater features in general would be greatly reduced if riparian areas were avoided by the power line, thus, parts of the corridors to be avoided have been identified and the alignment of the power line must avoid these areas as far as possible.

Water Use Authorisation Implications The placing and construction of infrastructure in any surface water feature and its associated riparian zone, including any electricity pylon or access road, as well the clearing of riparian vegetation would require an authorisation (licence) from the Department of Human Settlement, Water and Sanitation (DHSWS) as this activity would be likely to trigger one or more of the specified water uses under Section 21 of the National Water Act:

(c) impeding or diverting the flow of water in a watercourse; (i) altering the bed, banks, course or characteristics of a watercourse.

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the parts of the riparian corridor that are hydrologically activated by surface water. Due to the alluvial nature of these areas, these areas away from the part of the riparian corridor most associated with surface water hydrological activation have been included as an integral part of the riparian corridor. Mature woodland within these areas is dependent on shallow groundwater, but the very close interrelationship between surface water and this shallow groundwater entails that these areas of mature woodland cannot be divorced from the central part of the riparian area and have also been included. It is thus the position of this study that the entire length of the servitude through the riparian areas as delineated would need to be licensed as part of the authorisations required by this development.

As part of the studies for the Water Use Authorisation (WUA) process, a full assessment of the riparian corridors crossed will need to be undertaken. The requirements of the GN 509 of 2016 (General Authorisation in terms of Section 39 of the National Water Act, 1998 for water uses as defined in Section 21(c) or Section 21(i) of the Act must be complied with. Accordingly a risk assessment as detailed in GN 509 0f 2016 must be undertaken in order to determine the degree of risk to surface water (aquatic) features, and in order to determine which WUA process must be undertaken for the proposed project, i.e. a full Water Use License (WUL) or a General Authorisation (GA) process.

In support of the technical requirements of the WUA process it is likely that PES (Present Ecological State) and EIS (Ecological Importance and Sensitivity) Assessments of high priority surface water features along the alignment approved for development will need to be undertaken.

Comparative Assessment of Corridor Alternatives As part of the Surface Water Study a preferred corridor should be recommended from a surface water perspective. Two primary corridors (Corridors 1 & 2) that stretch the entire length of the proposed power line route between the Kappa and Gamma Substations have been presented for comparative assessment. Corridor 1 has been discarded, but a new shorter corridor alternative has been added in the south-western part of the study area – Corridor 1A.

As the newly added Corridor 1A only traverses a part of the entire length of the proposed power line, the comparative assessment has been undertaken in two parts:

◼ Within the part of the route in which all three corridors are located

◼ Within the remaining part of the route in which Corridor Alternatives 1 and 2 only are located.

Accordingly, in the section where all three alternatives are located, Corridor 2 is preferred from a surface water perspective,

Corridor 2 is marginally preferred along the remainder of the line

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Specialist Declaration of Independence

I, Paul da Cruz, declare that I –

▪ act as an independent specialist consultant in the field of surface water assessment; ▪ do not have and will not have any financial interest in the undertaking of the activity, other than remuneration for work performed in terms of the Environmental Impact Assessment Regulations (as amended), 2017; ▪ have and will not have any vested interest in the proposed activity proceeding; ▪ have no, and will not engage in, conflicting interests in the undertaking of the activity; ▪ undertake to disclose, to the competent authority, any material information that have or may have the potential to influence the decision of the competent authority or the objectivity of any report, plan or document required in terms of the Environmental Impact Assessment Regulations, 2014; and ▪ will provide the competent authority with access to all information at my disposal regarding the application, whether such information is favourable to the applicant or not.

PAUL DA CRUZ

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Acronyms

Acronym Acronym description

CBA Critical Biodiversity Area

DMA District Management Area

DWS Department of Water and Sanitation

EIA Environmental Impact Assessment

EIS Ecological Importance & Sensitivity

ESA Ecological Support Area

GN Government Notice

HGM Hydrogeomorphic

NFEPA National Freshwater Ecosystem Priority Areas

NSBA National Spatial Biodiversity Assessment

NWA National Water Act

PES Present Ecological Status

VEGRAI Riparian Vegetation Response Assessment Index

WCBSP Western Cape Biodiversity Spatial Plan

WMA Water Management Area

WUA Water Use Authorisation

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Glossary

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Glossary Term Glossary Text

Aeolian Wind-borne – i.e. referring to wind-borne and deposited materials, and erosion caused by wind

Alluvial Material / Sedimentary deposits resulting from the action of rivers, including those deposited deposits within river channels, floodplains, etc.

Baseflow The component of river flow that is sustained from groundwater sources rather than from surface water runoff.

Colluvium Weathered material that has been transported downslope by gravitational forces and which has been deposited in bottomlands

Ephemeral A watercourse that flows at the surface only periodically.

Episodic Relating to rivers and drainage lines typically located within arid or semi-arid environments that only carry flow in response to isolated rainfall events

Fluvial The physical interaction of flowing water and the natural channels of rivers and streams.

Herbaceous A plant having little or no woody tissue and persisting usually for a single growing season

Hydric / Soils formed under conditions of saturation, flooding or ponding for sufficient Hydromorphic Soils periods of time for the development of anaerobic conditions and thus favouring the growth of hydrophytic vegetation.

Hydrology The scientific study of the distribution and properties of water on the earth’s surface.

Hydromorphy A process of gleying and mottling resulting from intermittent or permanent presence of free water in soil. Results in hydromorphic soils.

Hydroperiod The term hydroperiod describes the different variations in water input and output that form a wetland, characterising its ecology – i.e. the water balance of the wetland.

Hydrophilic A hydrophyte.

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Hydrophyte A plant that grows in water or in conditions that are at least periodically deficient in oxygen as a result of saturation by water – these are typically wetland plants.

Interfluve A Watershed

Land type Distinct areas defined as part of the Land Type Survey of South Africa based on a unique combination of soil pattern, macroclimate and terrain form.

Levee An elevated bank flanking the channel of a river, being located higher than the level of the floodplain.

Phreatophyte A plant with a deep root system that draws its water supply from near the water table.

Reach A portion / stretch of a river / watercourse / wetland.

Redoximorphic Features within soil that are a result of the reduction, translocation and oxidation (precipitation) of Fe (iron) and Mn (manganese) oxides that occur when soils are saturated for sufficiently long periods of time to become anaerobic.

Riparian Zone The physical structure and associated vegetation of the areas associated with a watercourse which are commonly characterised by alluvial soils, and which are inundated or flooded to an extent and with a frequency sufficient to support vegetation of species with a composition and physical structure distinct from those of adjacent land areas.

Salinisation The process of salt accumulation in soil or water.

Stream Order A morphometric classification of a drainage system according to a hierarchy or orders of the channel segments. Within a drainage network the un-branched channel segments which terminate at the stream head are termed as “first order streams”

Watercourse A linear drainage feature; however it is important to note the legal context of the definition, in terms of the National Water Act and NEMA EIA Regulations. The Act defines a watercourse as (inter alia):

▪ a river or spring; ▪ a natural channel in which water flows regularly or intermittently; ▪ a wetland, lake or dam into which, or from which, water flows ▪ any collection of water which the Minister may, by notice in the Gazette, declare to be a watercourse as defined in the National Water Act A reference to a watercourse includes, where relevant, its bed and banks

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Understorey The part of the forest / woodland which grows at the lowest height level below the canopy.

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1 Introduction

The scoping-phase surface water study (completed in 2012) identified that riparian zones of a number of river systems across the study area are highly sensitive. Although not typically characterised by active flow of water, or the presence of hydric (wetland) soils, riparian zones of the larger river systems in the study area are a critical component of the surface water drainage environment in the area, as they are highly distinct from the surrounding Karoo veld in terms of their species composition and physical structure. Although important from a biodiversity perspective, these riparian zones are also very important in a surface water context as in terms of the National Water Act (Act 36 of 1998, as amended) they are defined as part of the rivers along which they occur in terms (as explored below). In the context of a semi-arid environment, these riparian environments are extremely sensitive as they are typically characterised by high levels of biodiversity and are critical for the sustaining of ecological processes as well as human livelihoods through the provision of water for drinking and other human uses. As such surface water resources and wetlands are specifically protected under the National Water Act and generally under the National Environmental Management Act, 1998 (Act No. 107 of 1998). Many of these riparian systems are extensive (very wide) and thus are at risk of being impacted by linear developments, including power lines. In the context of a power line development, the felling of vegetation above a certain height, or at worst the clearing of the entire servitude through the riparian zone of all vegetation constitutes an important surface-water resource-related impact. This report focuses on the potential impact of the proposed lines on the riparian zones of the larger river systems in the study area and highlights how the proposed power lines may impact these, and how the potential impacts can be mitigated.

1.1 Aims of the Study The aims of the study are to:

◼ assess as many of the riparian systems of the larger rivers in the study area as possible in the field, to determine their characteristics, and to determine the nature and degree of risk posed to them by the proposed power line;

◼ delineate all riparian zones that are sufficiently wide, or which are aligned in such a way in relation to the proposed power line corridors, that they are likely to be adversely affected by the proposed power lines;

◼ assess the impacts of the proposed power line on surface water features and their associated riparian zones, and suggest suitable mitigation measures, in particular proposed routing of the power lines through the respective corridors, to ameliorate or remove these predicted impacts;

◼ to comparatively assess the proposed corridor alternatives and identify a preferred corridor from a surface water perspective.

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1.2 Assumptions and Limitations The study has focussed on the larger river systems, due to the very large physical extent of the study area, and in order to focus on surface water features that are most likely to be adversely impacted by the proposed power line. The study has thus focussed on those drainage systems which are characterised by extensive riparian zones. The smaller drainage systems which are sufficiently narrow to be able to be singly spanned by the proposed power line, and which typically do not contain woody riparian vegetation, along with those drainage systems in the more mountainous parts of study area which do not contain extensive or wooded riparian zones have not typically formed part of the focus of this study, although generic mitigation measures for not impacting all surface water systems have been included in this report.

Due to access constraints, not all target drainage systems were able to be visited and thus assessed in the field. In these cases, the systems were only able to be delineated by desktop methods.

This report was previously undertaken as an EIA specialist report and has not been aimed at fulfilling the requirements of a water use licensing process. Although the principles of the VEGRAI riparian characterisation and assessment methodology have been taken into account in this report, a full EcoStatus assessment for the rivers potentially crossed has not been undertaken, as for such a large study area (with the corridors covering an enormous area) this was not practical (no alignment has been provided). Once an alignment has been proposed for the proposed power line, EcoStatus assessments will need to be undertaken for all potentially affected surface water resources as part of the Water Use Authorisation Process.

As discussed in section 1.4 below, a definition of wetlands that is slightly different to that provided by the National Water Act has been provided in this report. The definition used is based primarily on the presence of hydric soils, rather than on the hydroperiod of the surface water body.

1.3 Site Location and Description The Study Area is located within the interior of the Western Cape Province (and a small area of the Northern Cape Province) within the wider region known as the Great Karoo. The proposed corridor alternatives are extensively long and cover a large area; from an area close to the Northern Cape / Western Cape border north-east of Three Sisters in the north-east to the town of Touws Rivier in the south-west, passing close to the Karoo towns of Beaufort West, Leeu-Gamka, Merweville and Laingsburg.

The area traversed by the proposed power line and its alternative corridors is predominantly rural in character, with the majority of it consisting of farming areas characterised by livestock rearing (sheep and goats). Most of the area is thus vacant and undeveloped and has thus retained a natural or rural character.

The area traversed by the proposed power line is located within the terrain that is flat to undulating, with the presence of a number of hills and low mountain ranges punctuating the terrain. The power line corridors run over largely flat to slightly hilly terrain in the eastern half of the route. A topographical change occurs in the area to the west of Merweville where the lines traverse the foothills of the Roggeveld Mountains to the south of Sutherland, and in the area to the north-east of Beaufort West where the terrain is much more incised and hillier. The study area is indicated in the map in Figure 1.

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Figure 1 – Locality

1.4 Expertise of the author to compile this specialist assessment The author has compiled various specialist surface water / freshwater assessments, including several assessments for the development of power lines. The author thus has extensive experience in conducting such assessments.

The list of surface water / freshwater assessments compiled in the last ten years is detailed below.

• Wetland Delineation and EcoStatus Assessments for the Water Use Licence Application for the Margate Wastewater Treatment Works, KwaZulu-Natal, Ugu District Municipality • Surface Water Assessment Study for the Impendle Bulk Water Supply Water Use License Application, Impendle area, KZN, uMgungundlovu District Municipality • Wetland Delineation Assessment for a proposed sewer pipeline upgrade along Eastbury Road, Phoenix, Durban, eThekwini Municipality • Wetland Delineation and EcoStatus assessments for the KwaMeyi-Teekloof Bulk Water Supply Project. KwaZulu-Natal, Sisonke District Municipality • Wetland EcoStatus Assessments for the Dube Tradeport Agrizone, KwaZulu-Natal, Dube Tradeport • Undertook the Surface Water and Terrestrial Ecology Component of the Precinct Planning for the development of Precinct Plans for the Ekurhuleni Metropolitan Municipality

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• Wetland Delineation and assessment study for the construction of a road at the Ingula Pumped Storage Scheme, KwaZulu-Natal. mod • Wetland delineation and assessment study, as well as the compilation of a wetland rehab plan and risk assessment for the BA and WUA processes for the Decommissioning and replacement of a section of the Firham-Platrand Power Line, Mpumalanga • Freshwater Study (wetland assessment) for the Basic Assessment for the Development of a Battery Storage Site (Substation) near Mount Fletcher, Eastern Cape • Undertook the wetland component of the Freshwater Study for the project (Phases 1&2) for the Maintenance and/or Upgrade of the Patrol Roads and Fencing on the Borders between RSA, Swaziland & Mozambique – Phases 1& 2. • Wetland Delineation and Assessment Study, as well as wetland rehabilitation planning for the proposed NEO1 20MW Photovoltaic Power (PV) Generation Development Project in Mafeteng, Lesotho • Surface Water Assessment and Wetland Delineation for the Letaba NDP Project (Eskom Distribution) in the Tzaneen Area, Limpopo Province, Eskom Distribution • Wetland Delineation Assessment for the Kliphoek-Uitkoms-Panbult 132kV power line Basic Assessment in the Ermelo Area, Mpumalanga, Eskom Distribution • Wetland Assessment for the Valleyview Housing Development EIA, eMalahleni, Mpumalanga Province. Before the Wind Investments • Surface Water Assessment for the continued operation of the Matimba Ash Disposal Facility EIA, Lephalale, Limpopo Province, Eskom Generation • Surface Water Assessment for the Gamma-Kappa Transmission Power line EIA, Western Cape Karoo, Eskom Transmission • Wetland Delineation and Assessment Study for the proposed establishment of housing in Fochville, Gauteng, Fochville Municipality • Surface Water Assessment for the Lydenburg-Merensky 132kV power line, Mpumalanga-Limpopo Provinces, Eskom Distribution • Wetland Rehabilitation Plan for the Eskom UCG Plant Section 24G application, Amersfoort Area, Mpumalanga, Eskom Generation • Detailed wetland delineation and assessment study for the Eskom UCG Project, Amersfoort Area, Mpumalanga, Eskom Generation • Surface Water (Riparian) Assessment for the proposed development of a water pipeline near Groblershoop, Northern Cape, Solafrica • Wetland Delineation and Assessment Study for a proposed Biogas Digester Plant at Fort Hare, Eastern Cape, Fort Hare University • Wetland Delineation and EcoStatus Assessments for the development of an abattoir facility in Amersfoort, Mpumalanga; MDARDLEA

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• Wetland Screening Assessment at Barton Place, eThekwini Municipality, eThekwini Municipality • Wetland Screening Assessments for three proposed K-route roads in Gauteng, Gauteng Department of Transport • Surface Water Screening Assessment for the proposed Waterberg Heavy Haul Coal Transport Railway from Lephalale to Ermelo, Transnet • Wetland Delineation Assessments and Wetland EcoStatus Assessments (Wetland Functionality, Ecological Importance and Sensitivity and State Assessments) for the development of the proposed P166 Road in the Nelspruit-White River area of Mpumalanga, SANRAL • Wetland Delineation Assessment for a proposed waterborne sewer in eMpuluzi, Mpumalanga, MDARDLEA • Surface Water Study for the proposed Mbumbu-Tsakane Power line, Acornhoek area. Mpumalanga, Eskom Distribution • Wetland Delineation and EcoStatus assessments for the mining application for a quarry in Ekangala, Gauteng, City of Tshwane • Wetland and Riparian Assessment study for the proposed development of a cattle feedlot in Mzinti, Mpumalanga, MDARDLEA • Wetland Delineation Assessment for the proposed expansion and repair of the Rietspruit Dam wall in Ventersdorp, North West, DWS • Riparian Delineation and assessment studies for the development of a water pipeline in Roodeplaat, Gauteng, Magalies Water • Surface Water Assessment for the proposed Sanddraai Solar Power Plant, Groblershoop, Northern Cape, Solafrica • Riparian Assessment for the Derdepoort-Wegval Power line, North West, Eskom Distribution • Riparian Delineation and Assessment Study for the Mooinooi Power line Project, North West, Eskom Distribution

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1.5 Adherence to Appendix 6 of the EIA Regulations Table 1 below outlines how this report complied with Appendix 6 of the EIA Regulations

Table 1 – Findings of Compliance with Appendix 6 of the EIA Regulations Section of Stipulation: Relevant Section of the Report Appendix 6 1a A specialist report prepared in terms of these Title pages Regulations must contain— (a) details of— (i) the specialist who prepared the report; 1a A specialist report prepared in terms of these Section 1.5 Regulations must contain— Appendix 2 (a) details of— (ii) the expertise of that specialist to compile a specialist report including a curriculum vitae; 1b A specialist report prepared in terms of these Declaration of Independence (pg1) Regulations must contain— a declaration that the specialist is independent in a form as may be specified by the competent authority; 1c A specialist report prepared in terms of these Section 1.1 Regulations must contain— Section 3 an indication of the scope of, and the purpose for which, the report was prepared; 1cA A specialist report prepared in terms of these Section 3 Regulations must contain— an indication of the quality and age of base data used for the specialist report; 1cB A specialist report prepared in terms of these Section 6 Regulations must contain— a description of existing impacts on the site, cumulative impacts of the proposed development and levels of acceptable change; 1d A specialist report prepared in terms of these Section 1 Regulations must contain— the duration, date and season of the site investigation and the relevance of the season to the outcome of the assessment; 1e A specialist report prepared in terms of these Section 3 Regulations must contain— a description of the methodology adopted in preparing the report or carrying out the specialised process inclusive of equipment and modelling used;

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Section of Stipulation: Relevant Section of the Report Appendix 6 1f A specialist report prepared in terms of these Section 5. Regulations must contain— details of an assessment of the specific identified sensitivity of the site related to the proposed activity or activities and its associated structures and infrastructure, inclusive of a site plan identifying site alternatives 1g A specialist report prepared in terms of these Section 6.4.4 Regulations must contain— an identification of any areas to be avoided, including buffers; 1h A specialist report prepared in terms of these Section 4.2 Regulations must contain— Section 5. a map superimposing the activity including the associated structures and infrastructure on the environmental sensitivities of the site including areas to be avoided, including buffers; 1i A specialist report prepared in terms of these Section 1.2. Regulations must contain— a description of any assumptions made and any uncertainties or gaps in knowledge; 1j A specialist report prepared in terms of these Section 4. Regulations must contain— a description of the findings and potential implications of such findings on the impact of the proposed activity or activities; 1k A specialist report prepared in terms of these Section 6.4 Regulations must contain— any mitigation measures for inclusion in the EMPr; 1l A specialist report prepared in terms of these N/A as this is prepared for a screening Regulations must contain— study any conditions for inclusion in the environmental Section 9 contains recommendations authorisation; 1m A specialist report prepared in terms of these Section 6 Regulations must contain— any monitoring requirements for inclusion in the EMPr or environmental authorisation 1ni) A specialist report prepared in terms of these N/A as this is prepared for a screening Regulations must contain— study a reasoned opinion— whether the proposed activity, Section 9 contains recommendations activities or portions thereof should be authorised;

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Section of Stipulation: Relevant Section of the Report Appendix 6 1niA) A specialist report prepared in terms of these Regulations must contain— a reasoned opinion— regarding the acceptability of the proposed activity or activities; and 1nii) A specialist report prepared in terms of these Section 9 Regulations must contain— a reasoned opinion - if the opinion is that the proposed activity, activities or portions thereof should be authorised, any avoidance, management and mitigation measures that should be included in the EMPr, and where applicable, the closure plan; 1o A specialist report prepared in terms of these N/A – no consultation process was Regulations must contain— required to be undertaken a description of any consultation process that was undertaken during the course of preparing the specialist report; 1p A specialist report prepared in terms of these N/A – no consultation process was Regulations must contain— required to be undertaken a summary and copies of any comments received during any consultation process and where applicable all responses thereto; and 1p A specialist report prepared in terms of these N/A Regulations must contain— any other information requested by the competent authority.

1.6 Definition of Surface Water Features, Wetlands and Hydric Soils In the context of the delineation and assessment of surface water features in the study area, it is important to detail the definition of wetlands and hydric soils in order to set the parameters for the investigation.

1.6.1 Definition of Surface Water Features In order to set out a framework in which to assess surface water features, it is useful to set out what this report defines as surface water resources. In this context the National Water Act (Act No. 36 of 1998) is used as a guideline. The NWA includes a number of features under the definition of water resources, i.e. watercourses, surface waters, estuaries and aquifers. The latter two features do not apply in the context of this study as this report does not consider groundwater (in the case of aquifers) and estuaries are coastal features, thus surface waters and water courses are applicable in this context. The Act defines a watercourse as (inter alia):

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◼ a river or spring;

◼ a natural channel in which water flows regularly or intermittently;

◼ a wetland, lake or dam into which, or from which, water flows

The definition of a water course as used in the Act is taken to describe surface water features in this report. It is important to note that the Act makes it clear that reference to a watercourse includes, where relevant, its bed and banks.

It is equally important to note that the Act does not discriminate on the basis of being perennial, and any natural channel, however ephemeral, is included within the ambit of water resources. This definition is applied in this report.

1.6.2 Definition of Wetlands The NWA defines a wetland as:

“land which is transitional between terrestrial and aquatic systems where the water table is usually at or near the surface, or the land is periodically covered with shallow water, and which land in normal circumstances supports or would support vegetation typically adapted to life in saturated soil.”

This definition alludes to a number of physical characteristics of wetlands, including wetland hydrology, vegetation and soil. The reference to saturated soil is very important, as this is the most important factor by which wetlands are defined.

Another widely used definition of wetlands is the one used under the Ramsar Convention; wetlands are defined as:

“areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres”

However the presence / absence of hydric soils is the primary determining factor used to define a surface water feature as a wetland.

This determining factor has been utilised in this assessment. Wetland soils can be termed hydric or hydromorphic soils. Hydric soils are defined by the United States Department of Agriculture’s Natural Resources Conservation Service as being:

“soils that formed under conditions of saturation, flooding or ponding long enough during the growing season to develop anaerobic conditions in the upper part”.

These anaerobic conditions would typically support the growth of hydrophilic vegetation (vegetation adapted to grow in soils that are saturated and starved of oxygen) and are typified by the presence of redoximorphic features. The presence of hydromorphic (wetland) soils on the site of a proposed development is significant, as the alteration or destruction of these areas, or development within a certain radius of these areas would require authorisation in terms of the NWA and in terms of the Environmental Impact Assessment Regulations (2014)(as amended in 2017) promulgated under the National Environmental Management Act, 1998 (Act No. 107 of 1998, as amended).

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1.6.3 Definition of Riparian Zones This section briefly introduces riparian zones in terms of the hydromorphological and vegetation classification as per the VEGRAI (Riparian Vegetation Response Assessment Index) assessment methodology (Kleynhans et al, 2007) that has been developed to assess riparian zone state. The NWA defines riparian habitat as:

“The physical structure and associated vegetation of the areas associated with a watercourse which are commonly characterised by alluvial soils, and which are inundated or flooded to an extent and with a frequency sufficient to support vegetation of species with a composition and physical structure distinct from those of adjacent land areas”

As detailed in the guidelines for the delineation of wetlands and riparian areas (DWAF, 2005), riparian areas typically perform important ecological and hydrological functions, some of which are the same as those performed by wetlands. It is thus important that both wetlands and riparian areas be taken into consideration when making mandatory management decisions affecting water resources and biodiversity (DWAF, 2005).

Riparian areas include plant communities adjacent to and affected by surface and underground water features such as rivers, streams, lakes, or drainage lines. It is important to note that these areas may be a few metres wide along smaller systems or more than a kilometre in floodplains. Both perennial and non- perennial streams support riparian vegetation (DWAF, 2005).

Because riparian areas represent the interface between aquatic and upland ecosystems, the vegetation in the riparian area may have characteristics of both aquatic and upland habitats. Many of the plants in the riparian area require plenty of water and are adapted to shallow water table conditions. Due to water availability and rich alluvial soils, riparian areas are usually very productive. Tree growth rate is high. This is certainly the case in riparian zones in the study area as they typically contain trees and shrubs of a height, density and species diversity that is not present in the surrounding woodland.

Riparian areas are important as they perform the following functions (DWAF, 2005):

◼ storing water and thus assisting to reduce floods;

◼ stabilising stream banks;

◼ improving water quality by trapping sediment and nutrients;

◼ maintaining natural water temperature for aquatic species;

◼ providing shelter and food for birds and other animals;

◼ providing corridors for movement and migration of different species;

◼ acting as a buffer between aquatic ecosystems and adjacent land uses;

◼ can be used as recreational sites; and

◼ providing material for building, muti, crafts and curios.

These ecosystems may be considered ‘critical transition zones’ as they process substantial fluxes of materials from closely connected, adjacent ecosystems (Ewel et al, 2001)

As discussed below riparian habitat is important from a legislative perspective – in terms of the National Water Act.

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In terms of the VEGRAI structure, riparian areas are divided up into three (3) vegetation zones:

◼ Marginal Zone

◼ Lower Zone

◼ Upper Zone

This vegetation zone classification has been based upon:

◼ periodicity of hydrological influence

◼ marked changes in lateral elevation or moisture gradients

◼ changes in geomorphic structure

◼ changes in plant species distribution or community composition along lateral gradients

In spite of these zones being vegetative, they are also distinguished based on a combination of other factors including geomorphic structure and elevation along with vegetation. Elevation within the riparian zone is used as a surrogate for hydrological activation, which is taken to be moistening or inundation of the substrate by water in the channel. Figure 2 below (from Kleynhans et al, 2007) indicates a typical riparian zone:

Figure 2 - Schematic diagram indicating the three zones within a riparian area relative to geomorphic diversity (Kleynhans et al, 2007)

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Marginal Zone The marginal zone incorporates the area from the water level at low flow (where present – if flow is not present areas that would be subject to baseflows would be included) to those features that are more or less permanently inundated. Vegetatively the marginal zone is typically characterised by the presence of hydrophytes that are vigorous in terms of abundance due to the near-permanent availability of moisture.

Lower Zone The lower zone is the area of seasonal inundation (hydrological activation in this context is yearly inundation during high flows, or every 2-3 years), extending from the edge of the marginal zone to the point at which there is a marked increase in lateral elevation. This change in elevation may or may not be characterised by an associated change in species distribution patterns.

Upper Zone The upper zone is characterised by hydrological activation on an ephemeral basis (less than every 3 years) and extends from the end of the lower zone to the end of the riparian corridor. The upper zone is usually characterised by steeper slopes and the presence of both riparian and terrestrial species, the latter typically having an enlarged structure as compared to the areas outside of the riparian area.

2 Legislative Context

The following section briefly examines the legislation that is relevant to the scope of the surface water assessment. The stipulations / contents of the legislation and policy that is relevant to the study are explored.

2.1 The National Water Act It is important to note that water resources, including wetlands are protected under the NWA. ‘Protection’ of a water resource, as defined in the Act entails:

◼ Maintenance of the quality of the water resource to the extent that the water use may be used in a sustainable way;

◼ Prevention of degradation of the water resource

◼ The rehabilitation of the water resource

In the context of the current study and the identification of potential threats to the surface water features posed by the proposed road realignment and associated borrow pit establishment, the definition of pollution and pollution prevention contained within the Act is relevant. ‘Pollution’, as described by the Act is the direct or indirect alteration of the physical, chemical or biological properties of a water resource, so as to make it (inter alia)-

◼ less fit for any beneficial purpose for which it may reasonably be expected to be used; or

◼ harmful or potentially harmful to the welfare or human beings, to any aquatic or non-aquatic organisms, or to the resource quality.

The inclusion of physical properties of a water resource within the definition of pollution entails that any physical alterations to a water body, for example the excavation of a wetland or changes to the morphology of a water body can be considered to be pollution. Activities which cause alteration of the biological

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properties of a watercourse, i.e. the fauna and flora contained within that watercourse are also considered pollution.

In terms of Section 19 of the Act owners / managers / people occupying land on which any activity or process undertaken which causes or is likely to cause pollution of a water resource must take all reasonable measures to prevent any such pollution from occurring, continuing or recurring. These measures may include measures to (inter alia):

◼ cease, modify, or control any act or process causing the pollution

◼ comply with any prescribed waste standard or management practice

◼ contain or prevent the movement of pollutants

◼ remedy the effects of the pollution; and

◼ remedy the effects of any disturbance to the bed and banks of a watercourse

These general stipulations of the Act have ramifications for the proposed development as impacts on surface water features associated with the proposed development would be relevant in terms of the above stipulations of the NWA.

2.2 The National Water Act and Riparian Areas Riparian habitat is afforded protection under the National Water Act in a number of ways. Firstly reference in the National Water Act to a watercourse includes its banks, on which riparian habitat is encountered. Riparian areas are thus afforded the same degree of protection as the riverbeds and channels alongside which they occur.

Riparian habitat is also important in the context of resource quality objectives that are a critical part of the Act. In terms of Section 13(1) of the Act resource quality objectives must be determined for every significant water resource and are central part of data type specifications relating to national monitoring systems and national information systems as determined in Section 137(2) and Section 139(2) of the Act respectively. Under Section 27 of the Act resource quality objectives must be considered in the issuing of any licence or general authorisation and form a critical part of the duties of catchment management agencies. The purpose of resource quality objectives in the Act is to establish clear goals relating to the quality of the water resources. Resource quality is important in the context of riparian habitat as resource quality as defined in the Act means the quality of all aspects of a water resource and includes the character and condition of the riparian habitat. In terms of Section 26(4) of the Act, the need for the conservation and protection of riparian habitat must be considered in the determination and promulgation of regulations under the Act.

The above stipulations of the Act have implications for the proposed development; as identified further on in this report the proposed development may be associated with certain direct or indirect impacts on surface water features in the area, some of which may affect the physical characteristics of the feature. The activities that result in these impacts are likely to be needed to be licensed under the Act. The National Water Act also stipulates requirements for permitting which would need to be followed.

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2.3 International Policy Framework and Guidelines The relevant international policy framework and guidelines relevant for this assignment include, but not limited to the following;

2.3.1 The World Bank Policies The World Bank Operational Procedures (OP) 4.12, protects people’s right to land by stipulating to its investment partners that all involuntary resettlement should adhere to a number of basic principles for addressing the adverse effects of involuntary resettlement associated with its investment projects. These principles are: ▪ Involuntary resettlement should be avoided; ▪ Where involuntary resettlement is unavoidable, all people affected by it should be compensated fully and fairly for lost assets; ▪ Involuntary resettlement should be conceived as an opportunity for improving the livelihoods of the affected people and undertaken accordingly; and, ▪ All people affected by involuntary resettlement should be consulted and involved in resettlement planning to ensure that the mitigation of adverse effects as well as the benefits of resettlement are appropriate and sustainable.

2.3.2 The International Finance Corporation (IFC) Performance Standards The International Finance Corporation (IFC) Performance Standards are designed to assist the client in designing and implementing a project in a manner where risks and impacts associated with the project are identified and mitigated to ensure the project is completed sustainably. In the context of the surface water assessment the following IFC Performance Standards are applicable: • Performance Standard 1 (IFC PS1) – Assessment and Management of Environmental and Social Risks and Impacts • Performance Standard 6 (IFC PS6) – Biodiversity Conservation and Sustainable Management of Living Natural Resources

IFC PS1 is applicable to all projects which pose potential risk and may have an impact on the receiving environment. IFC PS1 (2012) states that should the host country have legislative control for the management of the environment that overlaps with the guidelines of the IFC standards, the more stringent measure should be implemented for the project. In the context of this, the stipulations of NEMA and the NWA, and associated licensing regimes should be applied. The objectives of IFC PS1 (2012), where applicable to the surface water study, are summarised as follows: ▪ The identification and quantification of environmental risks and impacts associated with the project, as well as the identification of -mitigation measures to be implemented at the site to minimise or avoid said risks and impacts; ▪ To encourage and ensure that the client runs the project as sustainably as possible using efficient and effective environmental management plans; and ▪ To ensure that relevant stakeholders (e.g. local communities, government, etc.) are aware of the project and their respective communications and queries are responded to and managed effectively. In the context of the above objectives, this study has attempted to identify and quantify all risks and impacts, as well as associated mitigation measures related to the proposed development on the surface water environment.

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IFC PS6 recognises that protecting and conserving biodiversity, maintaining ecosystem services, and sustainably managing living natural resources are fundamental to sustainable development. The objectives of IFC PS6 are: ▪ To protect and conserve biodiversity. ▪ To maintain the benefits from ecosystem services. ▪ To promote the sustainable management of living natural resources through the adoption of practices that integrate conservation needs and development priorities.

In a development context IFC PS 6 states that the client (a developer) will not significantly convert or degrade natural habitats, unless all of the following are demonstrated: ▪ No other viable alternatives within the region exist for development of the project on modified habitat; ▪ Consultation has established the views of stakeholders, including Affected Communities, with respect to the extent of conversion and degradation; and ▪ Any conversion or degradation is mitigated according to the mitigation hierarchy.

The IFC PS 6 stipulates that in areas of natural habitat, mitigation measures will be designed to achieve no net loss of biodiversity where feasible. No net loss of biodiversity is defined in the PS as: the point at which project-related impacts on biodiversity are balanced by measures taken to avoid and minimise the project’s impacts, to undertake on-site restoration and finally to offset significant residual impacts, if any, on an appropriate geographic scale.

Appropriate actions to ensure no net loss of biodiversity include: ▪ Avoiding impacts on biodiversity through the identification and protection of set-asides ▪ Implementing measures to minimize habitat fragmentation, such as biological corridors; ▪ Restoring habitats during operations and/or after operations; and ▪ Implementing biodiversity offsets.

The development of the proposed power line and the consideration of mitigation measures for the identified impacts must take the IFC performance standards, especially IFC PS 6 into account. Surface water features within the assessment corridors with wide riparian zones that would be significantly impacted by the proposed power line have been identified as areas to be avoided, in the context of the application of the mitigation hierarchy.

The exact impacts associated with a proposed alignment would need to be further assessed, and any offset- related implications, as deemed necessary through the Water Use Authorisation process would need to be further specified once a preferred alignment has been created.

2.3.3 Equator Principles Equator Principles Financial Institutions (EPFIs), have adopted the Equator Principles in order to ensure that the Projects financed advise on are developed in a manner that is socially responsible and reflects sound environmental management practices. EPFIs acknowledge that the application of the Equator Principles can contribute to delivering on the objectives and outcomes of the United Nations Sustainable Development Goals(SDGs), especially the avoidance of negative impacts.

The ten (10) Equator Principles are: • Principle 1: Review and Categorisation • Principle 2: Environmental and Social Assessment • Principle 3: Applicable Environmental and Social Standards

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• Principle 4: Environmental and Social Management System and Equator Principles Action Plan • Principle 5: Stakeholder Engagement • Principle 6: Grievance Mechanism • Principle 7: Independent Review • Principle 8: Covenants • Principle 9: Independent Monitoring and Reporting • Principle 10: Reporting and Transparency

In the context of the current project and its project stage, Principle 2 is most relevant. The EPFI will require the client to conduct an appropriate Assessment process to address, to the EPFI’s satisfaction, the relevant environmental and social risks and scale of impacts of the proposed Project. The Assessment Documentation should propose measures to minimise, mitigate, and where residual impacts remain, to compensate/offset/remedy for risks and impacts to Workers, Affected Communities, and the environment, in a manner relevant and appropriate to the nature and scale of the proposed Project.

As such this report has undertaken assessment and quantification of environmental (surface water-related) impacts and risks associated with the project and has proposed measures to mitigate such impacts.

3 Methodology for Assessment

3.1 Field Assessment and Riparian Zone Delineation An attempt was made to cover as many of the Study Area’s larger rivers and associated riparian areas as possible. Key or priority riparian areas were identified by desktop methodology in the scoping phase of this study, and an attempt was made to visit as many of these units as possible as permitted by project budget as well as access constraints.

For the rivers and associated riparian zones visited in the field a detailed coverage of the entire riparian zone as located within the context of the corridor was not possible, however a the approach of walking a transect across the riparian zone (perpendicular with the direction of the flow of the river / main channel) was undertaken. This approach was undertaken in order to acquire a good understanding of the profile of the riparian zone and to characterise the riparian zone in terms of its physical and vegetative components, thus allowing the riparian zone to be delineated in the field. Use was made of a GPS to identify important points (e.g. boundaries between different vegetation units). These GPS points were converted into a GIS shapefile to allow these points to be mapped and to facilitate the delineation of the riparian boundaries. Notes were taken regarding the predominant type of vegetation present within different parts of these riparian areas (e.g. to document the extent of Vachellia (formerly Acacia) karroo thickets or alluvial flats dominated by Salsola spp.)

3.2 Prioritisation of Riparian Areas As part of the outcomes of the riparian delineation process a spatial database of priority riparian areas within the study area was created. These were riparian zones of some of the larger rivers that are likely to be adversely impacted on by the power line if the power line were to be routed through them.

A number of biodiversity planning and EcoStatus layers were used to identify areas of environmental sensitivity. In addition riparian zones of a certain width (in particular those containing woodland of a certain width) were identified. Based on these criteria priority rivers and riparian zones in the study area were identified.

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3.3 Identification of Surface Water and Riparian Zone Impacts and Mitigation Measures All potential impacts that could be caused by the proposed development that would affect surface water features have been identified and detailed. Mitigation measures to either ensure that the identified impact does not materialise, or to ameliorate / limit the impact to acceptable levels have been stipulated.

All potential impacts that could be caused by the proposed power line and that would affect surface water features in the study area have been identified. Impacts specifically relating to the placing of servitudes through riparian areas have been investigated.

Mitigation measures to either ensure that the identified impact does not materialise, or to ameliorate / limit the impact to acceptable levels have been stipulated.

4 Findings of Assessment

4.1 Macro-Drainage Context The freshwater ecosystems that occur within rivers and wetlands, as well as the associated riparian habitats, are very important in the context of biodiversity, as unique plant and animal communities occur within them. This is particularly important in the context of the semi-arid Great Karoo, where the availability of moisture in the vicinity of drainage lines has led to the development of vegetation communities distinct from the surrounding Karoo plains. Due to the linear nature of this proposed power line, the corridor alternatives traverse a number of tertiary and quaternary catchments of rivers that generally flow in a southerly direction into the Indian Ocean.

The study area is located in a semi-arid climatic zone, receiving much less rain than areas to the south and west. The Cape Fold Mountains (such as the Swartberg to the south of the study area) form a barrier, creating a rain shadow in which most of the study area falls. The corridor alternatives traverse the interior of the Western Cape Province, in an area just to the north of the Cape Fold mountain ranges that separate the Little Karoo and the Indian Ocean coastline from the interior plateau. The following list details mean annual rainfall figures for various locations along the route corridors:

◼ Koru son Substation: 180mm/yr.

◼ Foothills of the Roggeveld Mountains: 200mm/yr.

◼ Beaufort West: 240mm/yr.

◼ Gamma Substation: 230mm/yr. (Source: SA Rainfall Atlas Database )

There is also a relatively strong seasonality in the rainfall figures, although the area traverses both the summer and winter rainfall areas, as the south-western part of the route around the Koruson Substation has a slight rainfall peak in the mid-winter months, while the north-eastern parts of the line have a peak in summer and late summer. The scarcity of rainfall and nature of precipitation also entails that rainfall events are episodic in nature; i.e. single rainfall events will contribute a relatively significant portion of rainfall.

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In a macro drainage context the corridors run close to the continental divide – the overall watershed that separates the catchments that drain into the Indian Ocean and those that drain into the Atlantic Ocean. Most of the quaternary catchments that are traversed by the power line corridors form the upper-most parts of rivers that drain south-wards towards the Indian Ocean. In the sections below the relevant quaternary catchment is stated behind the river draining it in parentheses

The north-eastern-most parts of the route cross certain areas within the upper-most catchment of the Groot River, itself a tributary of the Gamtoos River that flows into the Indian Ocean near Jeffreys Bay. A number of rivers flow into the upper parts of the Groot Catchment from the area north-east of Beaufort West as traversed by Corridors 1&2 – the Brak (L21A) and Tierhoek, Buffels, and Sand Rivers which form part of the Kariega River (L22A). The catchment of the Kambro River (L11D) is traversed by Corridor 2, and the lower reaches – the Sout River (L11E) are traversed by Corridor 1 to the south. The catchment of the Platdoring River (L11F) to the west is traversed by both corridors. (Refer to Figure 5)

The next major river system traversed by the power line corridor alternatives is that of the Gamka River. The Gamka River rises in the Great Karoo and flows south through the Groot Swartberg Mountain Range, joining with the Olifants River west of Oudtshoorn to form the Gourits River (primary catchment J) that flows into the Indian Ocean West of Mossel Bay. Within the study area a number of tributaries of the Gamka River drain the southern slopes of the Nuweveld Mountains west of Beaufort West, including the Leeu (J22K) (crossed by both corridors) and its tributaries the Kliplaatfontein and Sand (J22H) (crossed mainly by Corridor 2), Hottentots (J22J) (crossed by both corridors), and the Wilgerbos (J22E), Koekemoers (J22D), both of which are crossed by both corridor itself (Figure 4).

The upper Gamka River comprises quaternary catchments J21A and B (Figure 5) as crossed by both Corridors 1&2. J21D also forms part of the upper reaches of the Gamka, but only a very small part of it is crossed by Corridor 1 (Figure 4).

The Dwyka River (J24A&B) to the west is another tributary of the Gamka River, draining the area around Merweville to the west of Beaufort West. Both J24A&B are crossed by both Corridors 1&2 (Figure 4).

The next major river system to the west is the Buffels River that drains through the town of Laingsburg flowing south to become (another) Groot River, and flowing into the Gourits River. Corridors 1&2 and traverse the quarternary catchments in its uppermost reaches (J11A&B). A tributary of the Buffels River is the Meintjiesplaas River (J11D) which is crossed by Corridors 1&1A and marginally by Corridor 1. (Figure 3)

A small area traversed by the western-most extent of the power line corridors crosses the continental divide and crosses catchments characterised by north-westward-flowing rivers that eventually drain into the Atlantic Ocean as part of the Olifants River primary catchment (E) (Figure 3). The upper-most reaches of the Tankwa River catchment are traversed by the Alternative 1&2 Corridors, which cross the Tankwa, Wilgebos and Kleinbos Rivers within catchment (E23A). The upper reaches of the Ongeluks River which drains catchment E23G are traversed by Corridors 1A&2 (Figure 3). The Groot River (which becomes the Doring lower down) and its tributaries the Muishond and Smitswinkel Rivers drain catchment E22B which is traversed by all three corridor alternatives.

Figures 3-5 indicate the drainage in the wider study area.

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Figure 3 – Drainage and Quarternary Catchments in the South-western Part of the Study Area

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Figure 4 - Drainage and Quarternary Catchments in the Central of the Study Area

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Figure 5 - Drainage and Quarternary Catchments in the North-eastern Part of the Study Area

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4.2 Surface Water Typology and Occurrence The classification of surface water features in the study area has been based upon the most updated classification system for aquatic ecosystems in South Africa – the Classification System for Wetlands and other Aquatic Ecosystems in South Africa (Ollis et al, 2013). The system uses a six-tiered approach for classifying inland aquatic systems, including wetlands. Levels 4 and 5 (hydrogeomorphic (HGM) unit and hydrological regime respectively) are the focal points of the classification system – i.e. these describe the functional unit (Ollis et al, 2013). Table 2 below indicates the tiered classification for the different types of surface water features in the study area.

Table 2 – Tiered classification for aquatic environments in the study area Valley Bottom Wetlands Rivers and Watercourses Level 1 – System Inland Level 2 – Regional Setting (DHSWS(A) 21 – Great Karoo Ecoregions) (a small area of the study area in the far north-east falls into 18 – Drought Corridor) Level 3 – Valley Floor / Plain Slope / Valley Floor / Plain Landscape Unit Level 4A – HGM Un-channelled valley bottom wetland N/A Unit Level 4B – River longitudinal Upper Foothills & Lower Foothills Rivers / N/A zonation/Landform/ Streams (predominant) Outflow drainage Level 5 – River N/A Ephemeral (Perennial) Flow Types Level 5A – Period of inundation / N/A Hydrological Intermittently Inundated Regime Level 5B – Period Seasonally / Intermittently Saturated N/A of Saturation Natural vs. Artificial – Natural Natural vs. Artificial – Natural - Artificial (dam) Salinity - Fresh (non-saline) Level 6 – Other descriptors Vegetation Cover – Vegetated – Herbaceous – grasses Vegetation Cover – (Reeds) dominant Vegetated – Woody and herbaceous

Level 3 of the classification system is based on terrain setting. Surface water features (aquatic environments) can be found all across a landscape. The landscape can be divided up into a number of units, each of which can contain aquatic features. Wetlands occurring on these different terrain units typically differ in terms of their formative processes and hydrological inputs, and thus differ in terms of their functionality.

In the context of the study area, surface water features largely occur in valley floors or on wide plains (typical of large parts of the Great Karroo) where depositional processes predominate. Drainage in these settings is typically expressed as rivers / watercourses with defined riparian zones. However a number of much smaller, first order watercourses do occur in other, sloping terrain settings in the study area.

The low overall levels of precipitation across the study area and strong episodic nature of rainfall has had a strong formative effect on the hydrology of the study area (the level 5 descriptor of the classification system). Most rivers / watercourses are ephemeral or episodic in nature, i.e. only experiencing surface flow (if any) as a response to rainfall events, with flow typically occurring for a short amount of time. The National

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Freshwater Ecosystem Priority Areas (NFEPA) database lists all of the rivers in the study area with the exception of the Leeu / Gamka system and lower Dwyka system as being ephemeral (Driver et al, 2011).

As such most surface water drainage features are watercourses / drainage lines, with a defined channel. In spite of the irregularity of flow, fluvial processes do occur that shape the channel of the drainage feature. The nature of drainage typically depends on the nature of the topography; areas of more incised topography with a highly rocky substrate were generally observed to have a high drainage density (i.e. dense drainage), with a lot of small drainage features. These tend to occur high up within catchments, as first order streams that combine to form larger, more distinct drainage features downstream. Areas of flat topography with a sandier substrate were observed to be poorly drained, with a low drainage density. In certain areas drainage emanating from hilly rocky upland areas was noted to ‘disappear’ or dissipate as it flowed into areas of flatter topography. The NFEPA database includes a classification in terms of the geomorphic zone as calculated per slope category of Rowntree and Wadeson (1999).

In terms of the Level 4B descriptor of the classification system, most of the rivers and watercourses in the study area are upper and lower foothill streams, thus being reasonably well developed. Upper Foothill streams / watercourses are characterised as moderately steep, cobble-bed or mixed bedrock-cobble bed channels, with plane bed, pool-riffle or pool-rapid reach types. Narrow floodplains of sand, gravel or cobble are often present (Ollis et al, 2013). Lower foothills streams / watercourses are characterised as lower gradient, mixed-bed alluvial channels with sand and gravel dominating the bed of the feature which may be locally bedrock-controlled. Reach types typically include pool-riffle or pool-rapid, sand bars common in pools. Pools are of significantly greater extent than rapids or riffles, and floodplains are often present (Ollis et al, 2013).

Certain of the larger rivers such as the Gamka, Buffels, Dwyka and Groot that drain the study area were observed to be distinct from some of the smaller drainage features in a number of contexts; certain displayed a distinct macro-channel with active fluvial erosional processes at work (e.g. the Buffels River), while others displayed a very poorly defined channel structure with a wide alluvial floodplain defined by a distinct riparian zone (see below).

4.2.1 Riparian Zones The riparian zone as is commonly found along most rivers and drainage systems in the study area is arguably the most important aspect of surface water features, as it contains vegetation of composition and structure that is not found in non-riverine habitats. It is also the feature of surface water features that is most likely to be impacted by the proposed power line. Hence this report has focussed on riparian corridors in the study area – their characteristics and how these are likely to be impacted. In terms of the level 6 descriptor in Table 2 above, most surface water features in the study area are characterised by a mix of herbaceous and woody vegetation as detailed below.

Riparian zones support distinctive vegetation that differs in structure and function from adjacent aquatic and terrestrial ecosystems. Riparian zones form the interface between aquatic and terrestrial ecosystems and, except in broad floodplains, are relatively narrow, linear features across the landscape (Holmes et al, 2005). Certain riparian zones in the study area are akin to such wide floodplains and are extensive in width; however the vast majority are narrower, linear features in the landscape. A number of processes shape riparian areas; especially disturbances associated with aquatic systems, such as flooding, debris flows and sedimentation processes (Tang & Montgomery, 1995). Riparian plants are adapted to fluctuations in the water-table, as river levels alternate between low base flows and floods (Holmes et al, 2005). As discussed above, most of the rivers in the study area are episodic, with relatively scarce rainfall events causing short-

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lived periods of flow. However shallow alluvial aquifers appear to be the main driver of riparian vegetation in the drainage systems within the study area, as explored below.

Riparian areas are very important in the context of a number of ecosystem services that are provided in the wider Karoo geographic region. In the context of the Karoo, Mean annual precipitation (MAP) is a key determinant of soil moisture availability which, in turn, together with soil fertility, has a controlling influence on the production of digestible biomass (Le Maitre et al, 2009).There are only a certain number of days in a year when soil moisture does not limit plant growth, thus the growing seasons are short (Le Maitre et al, 2009).The increased availability of sub-surface moisture in riparian areas of drainage systems in the Karoo accounts for the much denser and larger structure of plants as compared to surrounding upland areas. Riparian areas thus provide important areas for the sustaining of livestock grazing, although it should be noted that overuse of these areas and certain factors like the ploughing of alluvial deposits have degraded the resource; as an example compositional shifts on the low lying areas from palatable perennial shrubs to dominance by unpalatable species such as Galenia africana have degraded these areas in terms of grazing value (Le Maitre et al, 2009). The prevalence of alien vegetation within riparian vegetation can also exert a significant impact on groundwater availability within riparian zones; groundwater is likely to be affected by deep-rooted alien invasive trees such as gums (Eucalyptus spp.), Prosopis and poplar (Populus spp.) (Milton, 2010).

4.2.2 Wetland Occurrence The Groot River mentioned above is the only major river in the study area (apart from certain smaller headstream systems in the foothills of the Roggeveld Mountains to the south-east of Sutherland) where typical wetland habitat, in the form of marshes or reedbeds was noted to occur within the riparian corridor 1. The National Wetland Map version 5 (NWM5) that shows the distribution of inland wetland ecosystem types across South Africa has been used to indicate the presence of wetlands across the study area. Figures 6- 16 indicate the presence of wetland occurrence across the study area.

According to the database wetland occurrence is typically restricted to narrow areas along the channels of certain river reaches, in particular the Dwyka River and its tributaries, Koekemoers River and its tributaries and the Leeu River and its tributaries. Along certain of the other larger river systems (for example the Leeu River near the Volmoed Farm within Corridor 1), the presence of structured grey soils in certain locations close to the channels where exposed by erosion was noted; these soils could qualify as gleyed hydric soils. This accords with the delineation of wetland habitat by the national database along such river reaches.

The National database also indicates that the Brak River at the far north-eastern end of the alignment is associated with extensive wetland occurrence (Figure 16). Smaller areas of wetland occurrence, not associated with the channel, but occurring within the riparian zone as delineated, are indicated to occur along the Rietkuil and Klipplaatfontein Rivers (tributaries of the Leeu), along small parts of the Platdorings system, and along certain short reaches of the Meintjiesplaas and Roggeveld Rivers.

The seasonality of rainfall differs across the study area, with the south-western parts of the study area receiving a greater proportion of winter rainfall than the north-eastern parts which are not situated within the core winter rainfall zone on the subcontinent, thus receiving bimodal rainfall. This is relatively important in terms of river flow and groundwater recharge, as when winter rainfall occurs the evaporative demand is relatively low and results in a greater proportion of the water being able to recharge groundwater and flow into rivers relative to the same amount of rain falling in a summer rainfall area (Le Maitre, 2009). This factor

1 It should be noted that wetland habitat along the Groot River was encountered in the discarded Corridor 1, which no longer forms part of the project scope.

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may explain why the only classical palustrine wetlands were noted to be located in the south-western part of the study area, and thus closest to the winter rainfall region.

4.2.3 Riparian Zone Delineation As noted above, riparian zones were delineated based not only on hydromorphological factors, such as channel structure and areas of surface water-related hydrological activation (as prescribed in the VEGRAI template) but also based on the presence of vegetation of differing composition and structure to the surrounding Karoo veld, and thus the presence of alluvial groundwater supply. In many of the larger river systems, the presence of areas of woodland is unlikely to be present due to surface water flooding due to the dry nature of the climate. However such woodland is always associated with a watercourse (even though distant from the main channel in certain cases), and the close interrelationship between surface water and groundwater has been explored above. These areas thus cannot be divorced from the more classically defined riparian zone alongside channels, and as such have been included in the areas delineated as part of the riparian zone.

The inclusion of these areas has implications for the impacting of riparian areas by the proposed power line in terms of the extent of riparian habitat potentially affected. The proposed power line could impact a relatively large swathe of riparian habitat if it crossed one of the wider riparian corridors, as explored further below. This also has implications for the licensing of the project in terms of the National Water Act, as the potential clearance of this riparian vegetation would need to be licensed under Section 21 c)& i) of the Act.

The riparian zones in the study area are indicated in the maps (Figures 6-16) below.

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Figure 6 – Riparian Areas in the Study Area – Groot River Area

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Figure 7 - Riparian Areas in the Study Area – Muishond River Area

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Figure 8 - Riparian Areas in the Study Area – Koornplaas Area

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Figure 9 - Riparian Areas in the Study Area – Vanwyksberg Area

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Figure 10 - Riparian Areas in the Study Area – Merweville Area

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Figure 11 - Riparian Areas in the Study Area – Leeu Gamka Area

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Figure 12 - Riparian Areas in the Study Area – Leeurivier Area

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Figure 13 - Riparian Areas in the Study Area – Beaufort West Area

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Figure 14 - Riparian Areas in the Study Area – Rhernosterkop Area

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Figure 15 - Riparian Areas in the Study Area – Three Sisters Area

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Figure 16 - Riparian Areas in the Study Area – Gamma Substation Area

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4.3 Freshwater Hydrology Most rivers in the study area are ephemeral / episodic, with only a handful assessed in the field being noted to contain flow, or even the existence of surface water in the form of residual pools. Flow regimes of rivers within the wider Succulent Karoo are highly erratic with prominent temporal and spatial variability in flows even in the larger rivers (Le Maitre et al, 2009). The nature of the soils in the catchments of drainage lines and riparian areas, especially with respect to clay soils, entail that soil or mineral crusting (dispersed clay particles can form a ‘cap’ that significantly blocks infiltration into the soil – Esler et al 2010) tends to be prevalent in overgrazed, bare areas. This has the result that when rainfall events occur there is a high degree of surface water runoff into the drainage systems, due to the reduced infiltration capacity in the soil. As a result the riverine habitats are naturally unstable and are subject to unpredictable flooding events, with consequent high levels of disturbance and soil movement (Palmer and Hoffman, 1997)

Only certain of the larger rivers were noted to contain flow or have surface water in residual pools during the site visits conducted in 2012, 2013 and in 2020 in the newly added Corridor 1A. The only rivers that were noted to be actively flowing during the site assessments in 2012 and 2013 were the Sout River (located south-west of Three Sisters – refer to Figure 17), the Buffels River near Laingsburg, the Gamka River along the N12 highway and the Leeu River downstream of the Leeu-Gamka Dam (although this is feed by discharge from the dam and is highly canalised). The Sout River was noted to contain a low flow (presumably a baseflow) within the main channel of the river during the June 2013 survey.

The Upper Gamka River (as well as certain of its tributaries such as the Kwagga stream) was noted to be flowing in the vicinity of the Droerivier rail siding as crossed by the N12 national road (located just to the south of Corridor 1) to the south-west of Beaufort West in November 2012. The same river was visited in the field at a slightly downstream reach (approximately 17km downstream) in May 2013 on the Steynskraal farm (within the now discarded Corridor 1), and the river was noted to be dry. This suggests that the Gamka River in the study area only flows irregularly in response to rainfall. Information provided by residents of the Beaufort West area suggested that the preceding winter had been characterised by a large degree of winter precipitation (snowfall) on the Nuweveld mountains which form part of the upper part of the Gamka catchment, followed by good early summer rains. Thus by the winter of the next year, the baseflow had either stopped, or been hydrologically transmitted into the underlying alluvial aquifers.

During the scoping phase site visit the Buffels River upstream of Laingsburg was also noted to be flowing. A tributary of the Meintjiesplaas River in the foothills of the Roggeveld Mountains to the south of the Komsberg Pass (in Corridor 2) was noted to be flowing. The presence of Phragmites reedbeds along this river suggests a relatively permanent water supply along this tributary. This is a tributary of the Buffels River to the south and is the presence of flow in the tributary is thus consistent with the lower reaches being perennial.

The presence of perennial flow is a very important feature from both an ecological perspective in the context of the rivers’ situation in a semi-arid context, and from a human water use perspective as water from some of these river systems rivers is utilised for irrigated cultivation. The latter use has resulted in physical modification of certain of the riparian corridors (e.g. the Leeu, Buffels and Groot), with the damming and downstream canalisation of the Leeu / Gamka River having historically occurred, and the transformation of large areas of the riparian habitat of this and the Buffels River systems to irrigated cultivation.

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Figure 17 – Flow along the Sout River within Corridor 1 in June 2013

Certain other river displayed residual pools (e.g. the Koekemoers, Waaikraal (Figure 19), parts of the upper Leeu River west of Beaufort West, the Groot2, Brak and Buffels Rivers). Importantly, these residual pools were mostly noted where outcropping of bedrock occurred. Fluvial action over geomorphological time has scoured out pools within the bedrock which in places are of sufficient depth to hold water for significant periods of time following flow events within the river. The hydrological connection between these pools and the surrounding alluvial substrate in the riverbed was evident in places as surface water ‘disappeared’ to remerge at a point slightly further downstream. A good example of such a hydrological process was noted in a tributary watercourse of the Buffels River near the Spitskop Farm in Corridors 1 &1A; the channel substrate changed in short reach of the watercourse from gravel to bedrock, and flow of water emerged from the gravel, flowing over the bedrock in the channel (Figure 18). Downstream where the channel bed substrate changed back to gravel, the surface flow disappeared into the gravel.

2 Although it should be noted that the Groot River and one of its tributaries, the Patatas River were noted to be flowing in November 2012.

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Figure 18 - Example of emergence of surface flow over bedrock outcropping from gravelly substrate and subsequent ‘disappearance’ in a tributary watercourse of the Buffels River in the Spitskop area (Corridors 1&1A)’

Certain of the other larger drainage systems such as the Dwyka River, although not characterised by surface flow and not being classed as perennial displayed extensive Phragmites australis reedbeds. This reed is typically an obligate hydrophyte (i.e. a species which only grows in saturated conditions), and thus the presence of the reedbeds along certain drainage systems suggests that a shallow groundwater table may exist along the riverbed that provides a foothold for the reeds.

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Figure 19 - Pools along the Waaikraal River at Kranskraal (Corridor 1)

In spite of the presence or absence of surface water the nature of surface water flows in most of the river systems sampled in the area is indicated by the presence of flood wrack. In this context flood wrack is the (primarily vegetative) material washed down river courses during flood / spate flow events, and which is trapped behind branches and other obstacles, remaining in situ after the flood has passed. The evidence of wrack beyond the active channel indicates that these areas were inundated by flood waters and provides a good indication of the extent of floods. Although it does not provide an indication of the frequency of flooding, it does give an indication that a spate flow did occur along the water course, and the position of the wrack horizontally away from the channel, and vertically above the channel bed indicates the extent of the flooding and the volume of water that passed along the system. In certain of the river systems sampled wrack was found at significant heights above the channel bed; e.g. in the Koekemoers River south of the Leeu-Gamka Dam3, wrack was noted at a height of approximately 2.5m above the channel bed. A flood event of this volume would inundate an area relatively far beyond the channel, which accords with the presence of alluvial material deposited in these areas.

Wrack was in evidence along most of the river systems sampled, most typically in the vicinity of the primary channel, and within and on the margins of secondary channels away from the main channel – i.e. the lower zone of the riparian corridor as characterised by the VEGRAI template. The presence of wrack indicates that significant flow events have occurred along most of the rivers in the study area. Rainfall events of sufficient intensity are associated with significant runoff, and this results in flows along the river systems for short periods of time. Once overland flow from the catchment area drops off, flows typically respond by decreasing. Surface water is typically transpired into alluvial sediments, or is lost to evaporation, with pools

3 In the now discarded Corridor 1; however, a flood event of this magnitude would have affected the upstream reaches within the current corridors in a similar manner

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remaining in areas of bedrock occurrence or in areas where the water table remains near the surface, as described above. This hydrological regime of no surface baseflow punctuated by short-lined flow events in response to rainfall is typical of ephemeral watercourses, as found across the study area.

The periodic occurrence of flooding has implications for the development of a power line, in that significant floods may affect the integrity of towers if these are placed within the 1:100-year floodline. It is accordingly important that towers not be placed within the 1:100-year floodline of any river. Floodlines determination does not form part of this study but will likely be required as part of the Water Use Application (see Section 7). The determination of floodlines for larger rivers and associated riparian zone will need to form an important part of the planning of the power line development once a final alignment has been determined. No tower should be placed within the 1:100-year floodline of any river or watercourse. Due to the required minimum clearance of the line to the ground (for a 750kV power line), the ground clearance of the line is unlikely to be affected by the floodline of any of the rivers crossed.

Figure 20 - Flood wrack trapped behind a Vachellia karroo shrub

There is evidence that many rivers in the Karoo have been subject to salinisation – a process of increased composition of salts within the waters of the river or watercourse. In these systems the natural levels of salinity of groundwater inflows to rivers have been aggravated by the relatively high volume of saline return flows, from excessive irrigation, relative to the amount of freshwater remaining in the river and the flushing ability of floods (Le Maitre et al, 2007). The most pronounced occurrence of salinity in the study area was noted to be present in in two rivers – the Groot River in the south-western part of the study area and the Brak River in the extreme north-east (Figure 21). Both systems were characterised by extensive occurrence of salt precipitate adjacent to the main channel, and extensive areas of poorly vegetated bare substrate that was noted to be highly erodible. The silty alluvial terraces adjacent to the primary channel are also

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characterised by highly saline or sodic soils and are characterised by plants that are adapted to grow in such conditions.

Figure 21 - Extensive salt precipitate along the Brak River (Corridor 1)

4.4 Groundwater-surface water interactions and implication for riparian zone delineation There is a strong interrelationship between groundwater and surface water in the rivers of this semi-arid area, with groundwater occurring in shallow alluvial aquifers that are hydrologically connected to the channels of the rivers. In many of the rivers sampled, deposits of alluvial material were noted, often taking up a large portion of the cross sectional profile of the riparian corridors. This alluvial material was noted to consist of coarser gravel and cobbles within, or close to the flow channels within the riparian zones, as well as sometimes extensive areas of fine silty material beyond the channels. These materials are of alluvial origin, although they are currently also controlled by aelioan (wind-blown) processes. This alluvium is hydrologically recharged by rain, surface water runoff, spring flow, flood recharge from rivers or by groundwater from the surrounding geology (IWR, 2011). In arid and semi-arid regions transmission losses of surface flow into alluvium can be substantial (IWR, 2011), and alluvial aquifers can hold relatively large volumes of water compared with rock-based aquifers where the water is confined to fractures and faults (le Maitre et al, 2009). The net accumulation of sediment from catchments in the areas of alluvial deposition along drainage lines and rivers is likely to have altered (increased) the groundwater-holding capacity of these systems, while possibly affecting surface water flows (le Maitre et al, 2009). This process of transmission of surface flow to shallow aquifers is important not only in its obvious effect on surface flow reduction, but also as a source of groundwater recharge to underlying alluvial aquifers. Due to the prevalence of alluvial sediment along most of the rivers in the study area, transmission of surface water

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(overland flows) into these river systems into the underlying alluvial sediment is expected to be extensive, being a strong factor in the presence of vegetation communities along these rivers that are supported by shallow groundwater. There usually is also a marked change in the vegetation composition and structure in areas where surface and groundwater accumulate. The presence of shallow groundwater was evident within the Leeu River riparian corridor to the west of Beaufort West on the farm Leeurivier (Corridor 2) where a drain had been excavated into the alluvial substrate approximately 50m away from the channel. The drain (about 1m deep) contained flowing water, having intersected the water table.

Figure 22 below illustrates the landscape-level interaction between groundwater in the rock-based aquifers within the catchments of rivers in the Karoo and the shallow alluvial aquifers encountered along rivers.

Figure 22 - Hypothetical cross-section of landscape showing the fractured sandstone aquifer of the Table Mountain Group overlying the fractured shales and groundwater discharges controlled by faults and by geological contacts (le Maitre et al, 2009)

This interrelationship between surface water and shallow alluvial groundwater is important in the context of how riparian zones as present within the larger rivers can be defined and delineated. The close hydrological interconnection between the surface water and the shallow alluvial groundwater means that surface water and groundwater within these river systems cannot be separated. This entails that vegetation of different structure and composition to the surrounding shrublands on the footslopes occurs within the outer parts of the riparian corridors, but that would not necessarily be defined as being part of the riparian zone as defined based on the area that is hydrologically influenced by surface water flows (which in these drainage systems is relatively limited in lateral extent). The presence of extensive areas of alluvial flats on which stands of often tall and dense Vachellia karroo woodland occur at distances of sometimes one kilometre or more cannot be attributed to surface flooding alone. These vegetation communities are likely to derive the majority of their required moisture inputs from alluvial groundwater. However as this alluvial groundwater is so closely connected with the surface water (when it does occur in these systems), it is postulated in this report that these wider bottomland thickets and woodlands are an integral part of the riparian zone, that in the context

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of the protection afforded to riparian zones in the National Water Act, should be subject to the same protection as parts of the riparian corridor located closer to the channel of the river. As such these areas of Vachellia karroo-dominated woodlands have been delineated as part of the riparian zones of the larger rivers in the study area.

4.5 Fluvial Morphology All rivers sampled contained a main (active) channel, a feature of most fluvial systems. The depth, width, and relative location of the channel differed amongst all of the rivers assessed in the field. Some of the larger rivers contained relatively wide, incised channels characterised by steep active channel banks (e.g. the Sout, Bloed, Dwyka and Waaikraal Rivers), and other rivers displayed a narrower, less incised channel with the presence of a number of secondary, lateral channels (e.g. the Platdorings and Koekemoers Rivers); in the case of the Waaifonteinspruit south-east of Three Sisters within Corridor 1 the ‘main’ channel was one of a number of small channels distributed across the riparian zone. In certain riparian settings (e.g. certain reaches of the Platdorings River to the east of Beaufort West), no channel-related fluvial feature was noted, and the extent of the wide riparian area consisted of alluvially-deposited silt and other fine material with localised longitudinal depressions the only indication of surface water movement within the wider drainage system. These are locally often referred to as ‘washes’ and are also encountered in association with the Groot and Muishond Rivers in Corridors 1 and 1A.

Channel beds typically consisted of cobbles rounded by fluvial action, typically deposited within the channel floor and on the inner bed. In certain of the wider channels (and in most of the smaller drainage systems) the channel bed consisted of finely weathered colluvium – dark brown in colour, presumably derived from weathered bedrock in the catchment (e.g. Figure 23 & 25).

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Figure 23 - Wide sandy channel bed of the Waaikraal River in Corridor 2

Areas adjacent to the active channel typically consisted of fine silty alluvial material, deposited by higher spate flows in the river (e.g. Figure 24). Along many of the river reaches assessed in the field, secondary, lateral channels were present immediately adjacent to the primary channel, at a slightly higher level. These secondary lateral channels were noted to be typically shallow (<0.5m deep), narrow features (e.g. Figure 24). In spite of being within the zone of most active hydrological activation by flows within the river, these secondary lateral channels were noted to be generally stable and well vegetated.

Along most of the larger river systems, alluvial terraces were noted to exist adjacent to the primary channel. These alluvial terraces consisted of fine silty substrate deposited in situ by fluvial action during large scale flood events. These alluvial terraces often occurred as extensive wide features within the larger river systems such as the Leeu, Gamka and Groot Rivers, in some cases extending to the outer edge of the riparian zone (to a point where the alluvial substrate was replaced by more structured, rocky soils in areas of increased slope slope). Where these extensive alluvial flats were found, these displayed characteristics of river floodplains, being characterised by relatively unconsolidated sediment, shaped by wind and water action to display undulating ‘micro-terrain’ in the form of low mounds and depressions. These mounds varied in size from 20cm to 2m in height in certain places. These areas were largely vegetated, with vegetation cover largely consisting of the salt-tolerant succulent shrub Salsola aphylla (as described further below) occurring in varying densities from a dense coverage to a much sparser coverage.

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Figure 24 - Alluvial deposits adjacent to the primary channel along the upper reaches of the Buffels River in Corridor 1 with a secondary lateral flow channel in the right of the picture

When examined spatially across the study area, rivers containing wider riparian zones with extensive alluvial terraces were found to more commonly occur in the area to the south-west of, and around Beaufort West than in the area to the north-east of Beaufort West. This could possibly be due to the topographical setting in the north-eastern part of the study area which is relatively mountainous, with fewer broad flats or valley bottoms across which the drainage systems run. A similar situation exists in the area in the hillier ground in the south-western part of the study area (such as in the catchments of the Muishond, Meintjiesplaas and Rooival Rivers), where the alternative corridors run through more incised terrain where riparian zones are constrained by the presence of rising, rocky ground through which both rivers run. In these settings the riparian corridor consists of a narrow band of riparian vegetation adjacent to the wide, sandy channels.

In certain riparian settings assessed in the field (e.g. the Gamka River at Steynskraal, the Leeu River at Volmoed or the Knoffelskloof River in the Spitskop area (Figure 25) in Corridors 1&1A), it was noted that the topographical setting of the river had a strong bearing on the width and spatial distribution of the riparian corridor in relation to the main channel. In certain areas assessed, the presence of a ridge or resistant rocky strata, against which the river has eroded over a period of geomorphological time entailed that the riparian zone between the channel and the resistant strata was either very narrow or non-existent, with the channel being located adjacent to the ridge or strata. In these situations, a very extensive riparian zone consisting primarily of extensive alluvial flats existed on the opposite side of the river, with floods depositing this material into a wider area due to the limitation of space adjacent to the far side of the channel.

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Figure 25 – The Knoffelskloof River near the Spitskop Farm in Corridors 1&1A, displaying little or no riparian corridor due to the presence of rocky strata on the edge of the channel

The heterogeneity of morphological settings of rivers and drainage systems in the study area can be analysed in terms of the VEGRAI model of the riparian zone. In all cases the marginal zone was limited to the channel. In most cases the marginal zone is not characterised by frequent hydrological activation, due to the ephemeral nature of the drainage systems, as discussed in Section 4.3 above. Nonetheless most of these systems display morphological indicators and vegetative indicators typical of the marginal zone.

The lateral extent of the lower zone differs markedly between different drainage systems in the area. In the larger systems the lower zone of the riparian corridor extends beyond the confines of the primary channel, with the presence of a number of parallel-running secondary channels that are hydrologically activated when higher flows occur along the system. In this context the lower zone can be relatively extensive in lateral extent. A case can even be made that secondary channels / depressions on the outer edge of the more extensive riparian corridors of certain of the larger river systems form part of the marginal zone, as they are characterised by trees and shrubs and a vegetative understorey typical of the secondary channels located closer to the main channel. Where chanellisation of the drainage system is poorly defined within the riparian corridor with the presence of numerous smaller channels distributed across the lateral extent of the riparian corridor bands of alternating lower and upper zones occur across the riparian corridor. This is true especially of the riparian ‘washes’ in the north-east and far south-western part of the study area such as the Platdorings and Groot River respectively. In the smaller systems the lower zone is much more limited in spatial extent, typically only occurring in a narrow zone between the channel bed and the start of the macro channel bank.

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Figure 26 - Channel on the outer edge of the Leeu River riparian corridor near Volmoed (Corridor 1). Although located far away from the primary channel, this is arguably part of the lower zone

In a classical riparian setting the upper zone occurs from the edge of the lower zone to the end of the riparian corridor. In the case of most of the larger riparian zones in the study area, the often-extensive alluvial flats that stretch from the channel margins to the edge of the riparian corridor comprise the upper zone. It is thought that these silty alluvial terraces are formed by very large floods occurring along the river system, thus having a fluvial (rather than colluvial) origin. The upper zone typically comprises the largest proportional area of riparian corridors, and in the case of most rivers in the study area is comprised of Salsola spp.- dominated flats / terraces. It could be argued that large parts of what have been included in the riparian corridors of the study area – the Vachellia karroo woodlands on the outer peripheries of certain of the larger systems would not fall into the classical model of the VEGRAI riparian template, as these are characterised by hydrological activation through groundwater rather than surface water flooding. Nonetheless due to the close interrelationship between surface water and groundwater as discussed below these areas have been included in the riparian zones as delineated and form a crucial part of the riparian corridors of the larger rivers.

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4.5.1 Vegetation Composition and Lateral Zonation Vegetation associated with surface water features in the Great Karoo region of the Western Cape differs greatly in composition and structure from the surrounding Karoo Shrubveld vegetation. Riparian zones support distinctive vegetation that differs in structure and function from adjacent terrestrial ecosystems. This marked change in the vegetation composition and structure is an indication of the presence of the accumulation of both surface and groundwater (le Maitre et al, 2009). This difference is expressed in the presence of two distinct vegetation types that occur within the study area and which are largely associated with the larger river systems.

Most of the larger rivers in the central and eastern parts of the study area fall within the Southern Karoo Riviere vegetation type, as defined by the National Vegetation Map of South Africa (Musina and Rutherford, -2006), as updated in 2018 (Refer to Figures 11-15). This vegetation type is characterised by narrow riverine flats that support a complex of Vachellia karroo or Tamarix usneoides thickets surrounded by tall Salsola- dominated species especially on heavier soils in a broad alluvial context. Stipagrostis namaquaensis occasionally dominates in sandy drainage lines (Mucina and Rutherford, 2006). Of the rivers the drain across the alternative corridors, the Koekemoers, Waaikraal, Gamka, Steyns, Kuils, Platdorings, Sout, Kambro, Waaifontein and Sout Rivers all fall within this vegetation type.

The rivers in the far south-western most parts of the study area fall within the Tanqua Wash Riviere Vegetation type (refer to Figures 6&7). This vegetation type is comprised of intermittent rivers supporting a mosaic of succulent shrublands with Salsola and Lycium species alternating with Vachellia karroo gallery thickets (Mucina and Rutherford, 2006). The Groot River and certain of its tributaries including the Muishondlaagte fall within this vegetation type. It should be noted that this vegetation type includes areas of plains adjoining the riparian zones.

The hydrology of the rivers and smaller drainage systems influences the vegetation through flooding, droughts and water-table fluctuations. Rivers are typically dynamic environments and flood events can change the channel structure and remove vegetation - riparian vegetation is shaped by disturbances associated with aquatic systems, such as flooding, debris flows and sedimentation processes (Holmes et al, 2005). Conversely fluvial processes can result in sediment deposition that provides new habitat for plant colonisation within the riparian zone.

The distribution of riparian vegetation types is primarily determined by gradients of available moisture and oxygen (Holmes et al, 2005). This is very important in the study area context - due to the ephemeral / episodic nature of most of the fluvial systems in the study area, riparian vegetation that occurs along these systems depends to a significant extent on groundwater availability to sustain the riparian vegetation communities. The relationship between riparian vegetation and groundwater is frequently complex; plants may source water stored in riverbanks or in alluvial aquifers. Moisture found within the substrate of drainage systems may emanate from periodic flooding that recharges into the aquifer or may be groundwater that discharges into the streams (le Maitre et al, 1999). The former is likely to be the case in the study area as discussed above.

Plants which are riparian specialists (referred to as obligate phreatophytes) are species adapted to fluctuating water tables; as such their roots typically remain in, or in contact with, the saturated soil layers (le Maitre et al, 1999). Although such species are typically vulnerable to long-term drawdown of groundwater levels due to over-abstraction (le Maitre et al, 1999), riparian plants are naturally adapted to fluctuations in the water-table, as river levels alternate between low base flows and floods (Holmes et al, 2005). A study by Milton (1990) demonstrated that rivers and associated riparian zones and washes had the highest plant species richness and structural diversity in the Karoo (in spite of occupying a minor percentage of the area), as compared to the surrounding plains and ‘heuweltjies’ (hillock) communities.

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A number of lateral zones typically occur across the cross-sectional profile of a riparian zone. Plant species attributes are important in determining which riparian lateral zones they occupy – this influences the structure and composition of different riparian communities (Holmes et al, 2005). In typical riparian zones where there is an active fluvial channel most species closer to the channel are able to survive the physical stress of frequent inundation due to flooding, whereas those at higher elevations tend to be intolerant of flooding but require access to the water table (Holmes et al, 2005). This template is not typically expressed in the rivers of the Karoo, as frequent flooding is not a significant factor. The occurrence of sometimes extensive areas of Vachellia karroo away from the channel corresponds with this spatial template to a degree, as these trees are likely to depend on access to shallow groundwater, rather than on fluvial inputs.

Figure 27 – Elevated view of the Leeu River riparian zone in Corridor 1 showing Salsola-dominated alluvial flats with Vachellia karroo woodland closer to the channel

Although heterogeneity in terms of the vegetative composition of rivers and drainage lines within the wide extent of the study area was noted, due to differing geological, hydrological, geomorphological and micro climatic templates, a typical vegetative lateral zonation structure of most rivers was evident. As such a number of lateral zones were evident across the riparian zones sampled in the field. The vast majority of rivers and drainage lines in the area display a central channel which carries flow during flow events. All channel margins are characterised by trees and shrubs that are larger than the surrounding upland vegetation. This is true even for the smallest ‘headwater’ drainage lines where the riparian zone is limited to the edge of the active channel, along which larger shrubs than the surrounding vegetation occur. Within the larger river systems, large shrubs and trees typically occur along the channel margins – on the channel banks or on adjacent flood terraces, and sometimes even within the channel bed, or on levees within the main channel. Apart from the riparian woodlands that tend to occur on the alluvial flats away from the channel in certain of the larger river systems, the largest trees and shrubs within the riparian corridor are

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associated with active channels and their margins. Taxa from many different plant communities occur along these drainage systems, with the taller woody species, such as Vachellia karroo, being most prominent (Holmes et al, 2005).

The most commonly occurring and dominant tree / shrub species in this part of the riparian corridor is Vachellia karroo. There are a few other tree and shrub species that were noted to occur along channel banks and margins, including Searsia lancea, Lycium hirsutum, L. austrinum, Diospyros ramulosa, as well as Melianthus comosus that was noted to occur along many channels within riparian corridors. The beds of larger channels where alluvial material (gravel and larger cobbles) were typically not vegetated and only in a few cases was the reed Phragmites australis noted to extensively cover the channel bed. However where pools of water occurred (such as along the Waaikraal River), small stands of Phragmites and Typha capensis occurred along the margins of these pools. As these species are obligate hydrophytes, their presence suggests that these pools are permanent. In many locations, the sedge Cyperus marginatus was found within the channel and in secondary channels as discussed below.

Away from the main (active) channel banks, smaller secondary channels oriented parallel to the main channel were noted to occur in many settings, especially in the wider ‘floodplain’ settings where the riparian corridor was very wide, or where the primary channel was poorly defined. These secondary channels are typically flooded during flood or spate events when the primary channel overtops its banks. The larger trees and shrubs associated with the margins of the primary channel typically occurred along these secondary channels, but vegetatively these secondary channels were typically defined by the presence of a better vegetated substratum. The dominant species here was noted to be the spiny grass Stipagrostis namaquaensis. Two other grass species typically occurred within this part of the riparian zone – Cenchrus ciliaris and Cynodon dactylon. The former species typically occurred in shaded settings, and where protected from grazing by the spiny Stipagrostis namaquaensis. Cynodon dactylon also typically occurred in shaded environments and was noted to form a ‘lawn-like’ coverage. All of the above-mentioned grass species perform a vital role in binding the often-unconsolidated sediment within this part of the riparian zone, protecting it from erosion by wind and water, and also providing ‘surface roughness’ that assists in the trapping of sediment.

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Figure 28 - Stipagrostis namaquensis along a secondary channel

Away from the active channel, alluvial terraces or flats were noted to occur in most riparian settings. As described above the substrate in these alluvial flats within the riparian corridor was typically fine silt or sand characterised by high salinity, with the presence of undulations in a micro-topographical context. The deep sandy alluvium provides a suitable environment for many annual taxa (Palmer and Hoffman, 1997). The dominant plant in this setting was the succulent shrub Salsola aphylla, sometimes occurring in high densities across these areas. This plant is tolerant of brackish soils and it is likely that this dominance reflects the presence of saline soils on these alluvial terraces. Other shrubs in this part of riparian corridors included the shrubs Lycium hirsutum, L. austrinum, and L. oxycarpum as well as the small tree Diospyros ramulosa. Other plants such as the succulent shrub Bassia salsoloides and Cadaba aphylla also occur on these alluvial terraces. The species occurs at different heights in different parts of the riparian zone, with the tallest shrubs being 2m or higher, and growths of lower specimens (c50cm) in height occurring in other places. This differentiation in height possibly reflects increased moisture availability.

Along the larger river corridors, riparian woodlands occupy a significant portion of the riparian zones. The species present within these woodlands (i.e. Vachellia, Searsia, Lycium and other genera) are more typical of savannah but are able to persist by tapping the alluvial and groundwater stores. It is notable that these ‘woodland’ habitats can occur well away from the area of most active hydrological activation, and that Vachellia karroo specimens of significant height (≥5m) can occur in these areas that are distant from the channel, forming a dense impenetrable thicket in places. The presence of woodland of such height and thickness is indicative of the presence of subterranean moisture availability in these alluvial flats. In such woodlands a grassy substrate was often present with Cenchrus ciliaris being the most prominent species in the understorey. Shrubs and trees form an open woodland or in well-watered situations can form a gallery woodland with a dense canopy layer (Le Maitre et al, 2009). Such woodlands were present along some of the larger river systems that are characterised by wide riparian corridors including the Gamka, Leeu, and

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Sout Rivers. Such woodland occurs along the Platdorings near the De Hoop farm north-east of Beaufort West (in Corridor 2). This drainage line forms a ‘wash’ more than a typical fluvial system. Of note from a vegetative perspective, this riparian corridor was noted to be one of the most species-diverse riparian corridors assessed in the study area with a number of tree and shrub species not encountered elsewhere, such as Carissa haematocarpa, and Pentzia incana.

Figure 29 - Dense Vachellia karroo thickets and luxuriant understorey within the Platdorings River riparian corridor in Corridor 2

In most riparian settings the margins of the riparian corridors (transition to the upland non-riparian zones) are characterised by alluvial flats, characterised by Salsola spp. as the dominant plant. Riparian zones were noted to end where the vegetation changed to typical Karoo dwarf Shrubveld (bossie veld), along with a change in slope and substrate.

In most of the riparian corridors assessed in the field, alien invasive vegetation did not form a dominant presence. Only in certain riparian settings, primarily along some of the larger rivers and associated riparian corridors was alien invasive vegetation of more significant density observed. The primary alien invasive species observed along most of the drainage lines in the area was the Australian Saltbush (Atriplex nummularia). This species was noted to occur widely across the study area, especially on alluvial flats away from channels, and on channel banks. Prosopis spp. (different introduced species have hybridised) was found along some of the larger drainage systems, in particular along the Gamka River south-west of Beaufort West. Other invasive species including Tamarix ramosissima, Nerium oleander (oleander), Argemone ochroleuca (Mexican poppy) and Nicotiana glauca were encountered within channel beds or on channel banks. The prickly pear Opuntia ficus-indica was present in many riparian corridors (on alluvial flats) but was never noted to be extensive in occurrence.

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Figure 30 - Atriplex nummularia and Prosopis within the Gamka River riparian zone near Steynskraal

4.6 Water Quality Water quality can be examined as a baseline aspect of surface water features. However as the area is characterised by extremely limited to absence of perennial surface water quality data. Where data is available for the study area from the DHSWS 4, rivers are typically less polluted in their headwaters, becoming more saline further downstream. It is important to note however that in certain cases elevated salinity values is natural in certain river systems.

When floods and spate flows do occur in the rivers of the study area, siltation typically becomes the most important surface water quality issue. Large volumes of sediment tend to be mobilised from runoff from the surrounding catchments, being transported as flows of high turbidity (Basson and Rossouw, 2003). This characteristic is greatly exacerbated by poor landuse practices.

The sparse population across most of the study area means that sources of pollution into surface waters are generally limited and mainly comprise wastewater discharges.

4 https://www.dwa.gov.za/iwqs/wms/data/000key.asp

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5 Freshwater Prioritisation

A number of GIS-based biodiversity and EcoStatus layers (shapefiles) were used to identify priority rivers and riparian areas in the study area. The following spatial databases were used in the first draft of this report:

◼ The National Freshwater Ecosystem Protection Area (NFEPA) Rivers database – the occurrence of unmodified or largely natural rivers in terms of the NFEPA River Condition Class

◼ The National Freshwater Ecosystem Priority Area (NFEPA) Wetland FEPA database – the occurrence of Wetland FEPAs and FEPA Wetland Clusters

◼ The High Priority River Reaches database for the Central Karoo District Municipality (and for the part of the study area that falls within the Winelands DMA) - River conservation status from NSBA with additional fresh water focal areas

◼ The Central Karoo District Municipality (and Winelands DMA) Critical Biodiversity Area database (areas identified as CBAs)

◼ The Central Karoo District Municipality (and Winelands DMA) sensitive wetlands database (based on the Cape Nature sensitive wetlands layer)

The Central Karoo District Municipality CBA spatial database, as part of the 2009 Central Karoo District & Cape Winelands DMA Biodiversity Assessment used in the first draft of this report (listed in red above) has been superseded by the 2017 Western Cape Biodiversity Spatial Plan (WCBSP) (Pool-Stanvliet et al, 2017). The sensitivity analysis has been rerun using the updated CBA database for the parts of the corridor alternatives which fall in the Western Cape. River and Wetland CBAs that form part of the CBA1 category, and the aquatic CBAs that form part of the CBA2 category have been used for the sensitivity analysis. The Northern Cape CBA database has been used for parts of the study area that fall within the Northern Cape. The database does not distinguish between aquatic and terrestrial CBAs. However as detailed in the associated technical report (Holness and Oosthuyzen, 2016), aquatic features of sensitivity included NFEPA designations, hence NFEPA designation was used as an indicator of freshwater sensitivity in the parts of the corridor that traverse the Northern Cape

Freshwater features (including riparian areas) that were located within at least two of the above designations were labelled as priority areas. Such priority areas can be considered as sensitive areas that should ideally be avoided by the proposed power line.

In order to provide an additional measure of sensitivity, particularly in the context of the potential impact of power lines on riparian woodland, riparian areas displaying the following characteristics were prioritised (and thus identified as areas to be avoided):

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The maps below (Figures 31-33) illustrate priority / sensitive riparian zones in the study area. It is important to note how many riparian / riverine corridors have been identified as being critical biodiversity areas (CBAs) as well as ecological support areas in the study area. This demonstrates the importance of riparian corridors for ecological functioning of the wider Karoo ecosystem and in terms of the maintenance of biodiversity. Sensitive surface water features have been utilised in comparatively assessing the corridors below.

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Figure 31 - Sensitive Surface Water Sites in the South-western Part of the Study Area

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Figure 32 - Sensitive Surface Water Sites in the Central Part of the Study Area

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Figure 33 – Sensitive Surface Water Sites in the North-eastern Part of the Study Area

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6 Impacts and Mitigation associated with the proposed power line

Transmission power lines are not typically associated with impacts on surface water resources within non- woody environments, as the power lines do not have a physical footprint over the length of the power line other than the footprint of each tower position. As the lines are strung above the ground and as the towers are spread approximately 400m apart, most wetlands and rivers are able to be ‘spanned’ by the power lines and thus avoided from being physically affected. Power lines can however be associated with impacts on surface water resources if the towers are placed within a river or wetland, or in wooded settings if they cross the riparian zone of a surface water feature (most relevant in this context). The process of constructing the power line can also cause impacts on surface water resources, especially if certain mitigation measures and procedures are not followed. These potential impacts are explored in greater detail below.

6.1 Impacts associated with placing towers within a surface water feature Towers / electricity pylons are large structures and are require foundations in order for the structures to remain standing. The process of excavating the foundations would disturb the substrate and entail the removal of soil and vegetation from parts of the footprint, as well as the potential damage to vegetation due to the movement of construction machinery in the vicinity. If towers are constructed within a surface water feature, this activity could potentially adversely affect the soil and vegetation through the compaction of damp soils, the trampling, smothering or removal of vegetation within the surface water feature and the resultant exposure of soils that could result in their desiccation and subsequent erosion. The presence of concrete, as well as machinery which may leak fuel into the surface water feature could result in the introduction of pollutants into the feature. The movement of heavy construction machinery into the surface water feature, especially wetlands and areas of alluvial soils, could result in the alteration of the sub-surface hydrology by creating conduits for the movement of water in the freshwater feature.

The placing and construction of a tower in a surface water feature would also require a licence from the Department of Water Affairs and Forestry as this activity would fall under one of the specified water uses under Section 21 of the National Water Act: (i) altering the bed, banks, course or characteristics of a watercourse5. The majority of the surface water features in the study area are small ephemeral drainage lines that are narrower than 400m and thus able to be spanned without the water course / wetland being physically affected. As an example, Figure 25 shows existing power lines spanning the entire riparian corridor of the Knoffelskloof River. However as most surface water features contain riparian zones that contain woody vegetation, the proposed power line is likely to affect the riparian zone of these watercourses as discussed below.

5 It should be noted that Section 21i) water uses are licensed together with Section 21c) water uses, as Section 21 c)&i) water uses under the National Water Act and its associated regulations.

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6.2 Potential Impacts of the construction and operation of the Proposed Power Line on Surface Water Features in the Study Area Even if towers are not placed within a surface water feature and its associated riparian zone, as discussed below, the process of constructing the power line could potentially impact surface water resources. A number of activities, especially those relating to the access of construction vehicles along the alignment of the power line being constructed can result in damage to and impacts on surface water resources. Construction vehicles and machinery that move along the alignment of a power line during construction would typically cross rivers and drainage lines. Accesses across these surface water resources may need to be constructed should existing accesses for vehicles not exist (this is often the case as power lines can run in rural settings in which there is little human infrastructure). Accordingly the following impacts on surface water can result from construction activities along the power line servitude:

◼ The uncontrolled interaction of construction workers with watercourses that could lead to the pollution of the water in these drainage systems. Examples of this may be the washing of equipment in water within the watercourse (in rivers with pools), dumping of construction material into the drainage system etc.

◼ The lack of provision of adequate sanitary facilities and ablutions on the servitude may lead to the direct or indirect faecal pollution of surface water resources.

◼ Leakage of hazardous materials, including chemicals and hydrocarbons such as fuel, and oil, which could potentially enter nearby surface water resources through stormwater flows. This may arise from their incorrect use or incorrect storage. This is not only associated with a risk of pollution of surface water, but with a risk of the pollution of shallow groundwater within the riparian zone due to the presence of typically highly permeable alluvial substratum.

◼ The incorrect mixing (batching) of cement could lead to siltation and contamination of watercourses, as described above.

◼ Inadequate stormwater management and soil stabilisation measures in cleared areas could lead to erosion that could cause the loss of riparian vegetation and which would lead to siltation of nearby watercourses.

◼ The creation of new access roads for construction traffic across watercourses may lead to the erosion of banks and disturbance of riparian vegetation that may trigger the further development of gulley (donga) erosion.

◼ Construction of accesses across watercourses may impede the natural flow of water. This would alter the hydrology of the watercourse. Uncontrolled access of vehicles through surface water features, in particular wetlands (where these occur) can cause a significant adverse impact on the hydrology and soil structure of these areas through rutting (which can act as flow conduits) and through the compaction of soils.

6.3 Impacts of power line servitude clearing on Riparian Zones A strip of vegetation is typically cleared under a power line in order to maintain the minimum degree of clearance between the top of the vegetation and the lines. All woody and larger herbaceous vegetation is cleared to a certain minimum height from the ground. This vegetation is also often cleared in the servitude to reduce the risk of a fire that could occur within the power line servitude from creating large amounts of smoke which could create a flashover that could disrupt the flow / supply of electricity along the line. There is an important distinction that needs to be made between the clearing of woody and other vegetation above a certain clearance (thus retaining the vegetation below the clearance height) and the practice of clearing a

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strip of land under the lines of all vegetation (refer to Figures 34 and 35 below that indicate such a practice within the study area).

The latter practice of clearing of all vegetation constitutes a particularly important impact in the context of the riparian zones which occur along most of the rivers, and smaller drainage lines in the study area as it impacts negatively on the structural integrity of the riparian zone. The removal of (woody) and other vegetation from the servitude is one of the most important impacts on riparian zones that can occur, as it alters the vegetative composition of the servitude, and exposes the understorey that is dependent to a large degree on the shade created by the canopy to the sun. Clearing of woody vegetation also exposes the understorey that is dependent on the protection offered by the typically spiny / thorny woody vegetation to grazing pressure by livestock. Combined these two factors can result in much of the understorey being lost. Erosion may result from the clearing of vegetation and die off of roots that bind the soil, thus potentially resulting in the inundation of downstream reaches with sediment causing the impairing of filtering functions associated with the riparian zone. In addition the clearing of most riparian vegetation from servitudes leaves the soils exposed to erosion – both water-borne and wind-borne erosion. This is significant as much of the substrate within the riparian corridors in the area was noted to be silty in nature and thus powdery and highly unconsolidated, thus being particularly vulnerable to erosion by water and wind if the vegetation cover than binds the underlying soil is removed.

The former practice noted above (of clearing only woody vegetation above a certain clearance height) is also associated with similar impacts as it removes the shading effect of the canopy that is so critical in the semi-arid climatic context.

Importantly the clearing of vegetation (in particular the clearing of all vegetation) introduces another potential impact– that of the invasion of the riparian zone by alien invasive vegetation. This introduces the edge effect which can have an important effect on biota within the riparian zone, and create a very convenient ‘entry point’ into the riparian zone and wider riverine corridor for alien invasive vegetation – such human-related disturbances further exacerbate the natural susceptibility of riparian ecosystems to invasion by alien plants, as the transformed habitat is highly suitable for colonisation by alien invasive plants, and is less suitable for the less aggressive indigenous riparian species (Holmes et al, 2005). Riparian zones are particularly vulnerable to invasion by alien plants due to their dynamic hydrology and opportunities for recruitment following floods (Holmes et al, 2005). Servitude clearing is similar in that the cleared area is similar in nature to an area of the riparian corridor where flooding has washed away much of the vegetation. Many alien invaders of riparian habitats in South Africa are tall trees with higher water consumption than the indigenous vegetation (Holmes et al, 2005), and this could affect the vegetation-groundwater balance. Although the actual spatial area of the cleared servitude is likely to be relatively small in the context of the wider riparian corridor, this could create a convenient foothold for the invasion of wider areas of the riparian corridor and initiate an impact over a much wider area than simply the cleared servitude.

6.3.1 Potential Impacts specific to priority riparian areas in the study area Such clearing of a riparian area was noted along the Sout River to the south of Restvale in the Alternative 1 corridor (Figures 34 & 35). Existing 765kV lines cross the riparian area which is relatively wide. The Sout River is one of the few rivers in which surface water flow was noted in the study area (refer to Section 4.3 above), and displays a wide riparian zone consisting of Vachellia karroo thickets and Salsola aphylla alluvial flats. Most vegetation within the servitude of the 765kV line was noted to have been cleared. This included all woody vegetation, as well as all other herbaceous vegetation, with very little residual vegetative cover, except for small patches of grassy vegetation that had been retained. Consequently a significant portion of the servitude was noted to be un-vegetated. This is a significant factor as the (mostly alluvial) substrate has been left exposed to erosion by wind and water. Importantly vegetation on the banks of the active channel

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under the servitude was also cleared. The active channel bank, although relatively high above the active channel bed, is part of the riparian zone that is subject to the greatest degree of hydrological activation, and the clearing of vegetation from the banks has left the substrate on the steep banks highly vulnerable to erosion in times of spate flows / floods along the river, as well as vulnerable to erosion caused by the movement of livestock in and out of the channel. The exposed soils are an excellent ‘foothold’ for alien invasive plants, due in part to a lack of completion from existing vegetation, although no aliens were noted in the vicinity of the servitude.

Figure 34 - Existing power line servitude within the riparian corridor of the Sout River in Corridor 1 cleared of all herbaceous vegetation

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Figure 35 - Power line servitude within the riparian corridor of the Sout River in Corridor 1 cleared of most vegetation with extensive bare areas

As stated above, the larger river systems in the study area are characterised by extensively wide riparian zones – up to 2km in width. Many of these systems contain extensive stands of Vachellia karroo and other tree species that form open woodland or even closed thickets. Should a power line servitude cross these areas at their widest point, a large area of riparian habitat would be lost or severely modified. As an example, the clearing of a strip of 30m of vegetation across a 2km-wide riparian corridor would entail a loss / modification of 6ha of riparian habitat. Although 6ha may not be significant on its own, when the cumulative loss of / modification of riparian habitat across the numerous riparian zones traversed by the proposed power line is considered, the cumulative area of modification / loss could be significant. The loss or modification of riparian vegetation within a system must also be viewed in the context of existing impacts on riparian areas in the study area that include the abstraction of groundwater and consequent lowering of water tables, damming of rivers with resultant reductions in flow, the transformation of riparian habitat through cultivation in certain areas, and the degradation of riparian areas through overgrazing with the resultant dominance of non-palatable plant species.

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6.4 Mitigation Measures

6.4.1 General Mitigation Measures related to surface water features and riparian zones There are a number of general mitigation measures that are specified for all river riparian zone crossings.

◼ Firstly, as the vast majority of the rivers and watercourses along the line are sufficiently narrow to be spanned, no towers must be placed within the boundaries of any riparian zone of any watercourse that is sufficiently narrow to be singly spanned.

◼ The clearing of riparian vegetation has been identified to be a potentially significant cause of localised impact on watercourses and rivers, thus clearing of riparian vegetation should be limited as far as possible. Clearing / felling of woody vegetation should be limited to trees / shrubs above the maximum permitted clearance height, and the understory should not be cleared.

◼ All rivers and watercourses and their associated riparian zones should be treated as highly sensitive areas, and be strictly maintained as ‘no-go’ areas, except in the case of construction activities such as stringing of the lines and clearing of vegetation. No lay down areas should be placed within riparian corridors, and no new construction right of ways should be created through or across watercourses (other than where existing roads / accesses cross watercourses).

◼ Where surface water is encountered within rivers or watercourses, this should not be utilised for abstraction, or washing of equipment, etc., in order to minimise the risk of pollution of the water by construction activities. All abstraction of water from any surface water feature must be authorised as prescribed by the National Water Act and be subject to the provisions of any water use licence or general authorisation.

◼ No temporary roads or construction accesses must be constructed through any surface water feature.

6.4.2 Recommended Walk Down When the route of the power line is being finalised in the pre-construction phase, the proposed tower positions must be subject to a walk down by a surface water specialist in order to confirm that no towers are to be placed within a surface water feature, and in order to guide the alignment of the proposed power lines through riparian areas. A crucial aspect of this walk down will also be to assess whether planned access routes for construction vehicles would cross / traverse any surface water features, and to highlight any no- go areas in this context. The walkdown can also be used to undertake the assessments of each crossing on the affected reach of the river / watercourse and its riparian corridor as detailed above.

As a Water Use Licensing process will need to be followed for the proposed project, VEGRAI assessments will need to be undertaken for the riparian areas that are traversed and through which a servitude would be cleared. It is recommended that the walk-down be used to conduct the VEGRAI assessments.

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6.4.3 Alien Invasive Plant Management within servitudes during operation The encroachment of alien invasive plant species has been identified as significant potential impact acting on riparian corridors within the Karoo, as well as being associated with the clearing of servitudes through the riparian corridor. It is thus critical that operational procedures for the management of the servitude and removal and prevention of proliferation of alien invasive vegetation be strictly enforced. This must be undertaken at an interval of at least 6 months. Although the removal and management of riparian vegetation is most important within the riparian zone, it is also very important that parts of the servitude adjacent to the servitude (outside of riparian zones) also be subject to similar measures as without this the servitudes outside of the riparian zones would become ‘springboards’ for proliferation into the riparian area.

6.4.4 Recommended areas within corridors in which the proposed power line should not be routed All major riparian zones within the respective corridors have been delineated and mapped (refer to Figures 6-16). In a number of instances the riparian zone narrows within a certain part of the corridor, or the river only traverses a certain part of the corridor. Impacts on riparian zones and on freshwater features in general would be greatly reduced if riparian areas were avoided by the power line, thus as part of the mitigation measures recommended in this report, parts of the corridors recommended to be avoided have been identified and are indicated in the maps below (Figures 36-46). Routing of the power line must take these recommended areas to be avoided by the power line into account and as many of these areas as possible should be avoided.

As detailed in Section 5 above, such areas recommended to be avoided were identified as:

◼ In certain parts of the study area (i.e. in the far south-western parts of the corridor near the Kappa Substation, and in the areas to the north-east of Beaufort West), ‘washes’ were encountered. These washes have typically been included in the areas recommended to be avoided as the constitute a form of riparian zone that should not be unnecessarily impacted.

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Figure 36 – Parts of the Corridors to be avoided – Map 1

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Figure 37 - Parts of the Corridors to be avoided – Map 2

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Figure 38 - Parts of the Corridors to be avoided – Map 3

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Figure 39 - Parts of the Corridors to be avoided – Map 4

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Figure 40 - Parts of the Corridors to be avoided – Map 5

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Figure 41 - Parts of the Corridors to be avoided – Map 6

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Figure 42 - Parts of the Corridors to be avoided – Map 7

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Figure 43 - Parts of the Corridors to be avoided – Map 8

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Figure 44 - Parts of the Corridors to be avoided – Map 9

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Figure 45 Parts of the Corridors to be avoided – Map 10

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Figure 46 - Parts of the Corridors to be avoided – Map 11

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6.5 Impact Rating Matrix

Significance Phase Potential Aspect and/or Impact Mitigation Extent (E) Duration (D) Intensity (I) Probability (P) (E+D+I)*P

Moderate Aspect: Without 3 4 4 0.75 -8.25 Construction of the power line. Negative Impact: Low With 2 2 2 0.5 -3 -Direct transformative impact on Negative riparian zones of larger watercourses and rivers related to the clearing of a strip of all vegetation (under a worst-case scenario) -Damage to riparian corridors and watercourses through the Construction construction of roads / vehicle Key mitigation measures: access routes across ▪ Stringing of lines across watercourses to be undertaken in as labour intensive a manner as watercourses possible (i.e. minimal use of heavy equipment in riparian corridors) ▪ No creation of new roads / vehicle accesses through riparian corridors or across watercourses -Other construction-related ▪ Implementation of Stormwater Control Measures on the construction site activities including uncontrolled ▪ Construction staff must not enter any wetlands and surface water features outside of the movement of vehicles and other servitude footprint. construction machinery in ▪ Implementation of rehabilitation efforts. wetlands.

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Significance Phase Potential Aspect and/or Impact Mitigation Extent (E) Duration (D) Intensity (I) Probability (P) (E+D+I)*P

Moderate Aspect: Without 3 4 4 0.75 -8.25 Operation and maintenance (if Negative required) of the power line. Low With 2 4 2 0.2 -1.6 Maintenance of the servitude (i.e. Negative vegetation clearing) Impact: Direct transformative impact on riparian zones of larger watercourses and rivers related to the clearing and maintaining of a cleared strip of all vegetation Operation Key mitigation measures: (under a worst-case scenario) ▪ Avoidance of wide riparian corridors in routing of line under the lines. ▪ Clearing of only woody vegetation above the clearance height in a narrow strip under the lines, -Damage to riparian corridors and not clearing all vegetation within the entire servitude. (habitat degradation) in the event ▪ Ongoing rehabilitation of any new erosion. of vehicle / equipment access for ▪ Ongoing alien invasive vegetation management in the servitude line maintenance. -Invasion of the servitude by alien invasive vegetation

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7 Water Use Authorisation Implications

The placing and construction of infrastructure in any surface water feature and its associated riparian zone, including any electricity pylon or access road, as well the clearing of riparian vegetation would require a licence from the Department of Human Settlement, Water and Sanitation (DHSWS) as this activity would be likely to trigger one or more of the specified water uses under Section 21 of the National Water Act:

(c) impeding or diverting the flow of water in a watercourse; (i) altering the bed, banks, course or characteristics of a watercourse.

Section 21i) is the most applicable water use in the context of the proposed project, as servitude clearing associated with the construction and operation of a power line entails the removal / destruction of vegetation within the servitude. As explored in Section 6.1 above, 21i) would be initiated with the clearing of vegetation from the riparian zone, and as such the crossing of every watercourse no matter how large or small, in which riparian vegetation is removed / disturbed, would need to be licensed.

In the context of riparian areas in the study area as discussed above, many of the larger systems contain wide riparian corridors that stretch beyond the immediate surrounds of the banks of the main channel, with the presence of alluvial flats and in some places mature Vachellia karroo-dominated woodland away from the parts of the riparian corridor that are hydrologically activated by surface water. Due to the alluvial nature of these areas, these areas away from the part of the riparian corridor most associated with surface water hydrological activation have been included as an integral part of the riparian corridor. Mature woodland within these areas is dependent on shallow groundwater, but the very close interrelationship between surface water and this shallow groundwater entails that these areas of mature woodland cannot be divorced from the central part of the riparian area and have also been included. It is thus the position of this study that the entire length of the servitude through the riparian areas as delineated would need to be licensed as part of the authorisations required by this development.

As part of the studies for the Water Use Authorisation (WUA) process, a full assessment of the riparian corridors crossed will need to be undertaken. The requirements of the GN 509 of 2016 (General Authorisation in terms of Section 39 of the National Water Act, 1998 for water uses as defined in Section 21(c) or Section 21(i) of the Act must be complied with. Accordingly a risk assessment as detailed in GN 509 of 2016 must be undertaken in order to determine the degree of risk to surface water (aquatic) features, and in order to determine which WUA process must be undertaken for the proposed project, i.e. a full Water Use License (WUL) or a General Authorisation (GA) process. It is important to note that individual water crossings will not need to be licenced separately, but that they will form part of an integrated Water Use Application for the entire alignment.

In support of the technical requirements of the WUA process it is likely that PES (Present Ecological State) and EIS (Ecological Importance and Sensitivity) Assessments of high priority surface water features6 along the alignment approved for development will need to be undertaken.

Lastly Section 21 a) – “taking water from a water resource” may also be incurred if abstraction from a surface water feature (or groundwater) is undertaken as part of this project. It is very strongly recommended that no surface water be abstracted as part of the construction of the power line due to the scarcity of surface water in the study area.

6 On a linear project of very large spatial extent such as the current project it is recommended that a prioritisation exercise of surface water features that would need to be assessed in terms of their PES and EIS be undertaken. The undertaking of, and approach for such a prioritisation exercise would need to be subject to the agreement of the DHSWS at a WUA pre-application meeting.

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Approval from the relevant department (DHSWS) would need to be acquired before any related construction activities could start.

8 Comparative Assessment of Corridors

As part of the Surface Water Study a preferred corridor should be recommended from a surface water perspective. Two primary corridors (Corridors 1 &2) that stretch the entire length of the proposed power line route between the Kappa and Gamma Substations have been presented for comparative assessment. Corridor 1 has been discarded, but a new shorter corridor alternative has been added in the south-western part of the study area – Corridor 1A.

As the two primary corridor alternatives run in parallel – in a south-west to north-east orientation – and as rivers and drainage lines all roughly drain in a north-south orientation from the great escarpment (formed by the Roggeveld and Nuweveld Mountains and their extensions in the study area) towards the Indian Ocean, all of the larger river systems traverse these two corridors, meaning that the larger river systems run through each corridor.

As the newly added Corridor 1A only traverses a part of the entire length of the proposed power line, the comparative assessment has been undertaken in two parts:

◼ Within the part of the route in which all three corridors are located

◼ Within the remaining part of the route in which Corridor Alternatives 1 and 2 only are located.

A few factors can be considered when comparatively assessing the corridors: ▪ the comparative number of priority rivers and associated riparian areas ▪ the comparative number of larger riparian areas, especially those that contain significant areas of riparian woodland

Table 3 below lists these features per corridor in the part of the route in which all three corridors are located:

Table 3 – Comparative Assessment of Corridors in the South-western part of the Study Areas Corridor Sensitive/ Prioritised Surface Areas to be avoided (large Water Features riparian areas) Corridor Alternative 1 6 3 Corridor Alternative 1A 6 3 Corridor Alternative 2 4 3

As can be seen from the table above, the corridors differ very little in terms of the respective number of sensitive surface water features and number of areas recommended to be avoided by the power line within each corridor, due to the relative proximity of each corridor alternative over a relatively short distance in the context of the wider route. Accordingly a finer-scale examination of the location of the areas recommended to be avoided is more useful. Figure 36 indicates the location of two such designated avoidance areas located to the east of the confluence of the Groot and Muishond Rivers. These areas occur in the context of the terrain setting which is flat in the area of the confluence and in the lower-most reaches of the Muishond River. The Muishond River mostly drains through the hilly, incised terrain of the Koedoesberge Hills, but in its lower-most reaches drains into a much flatter area, thus allowing the riparian corridor to widen. The flat

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terrain is conducive to the occurrence of a number of washes in the same areas, creating a wide area of freshwater habitat. In this context when the alignment of the various corridors is considered, Corridors 2 and 1A would need to cross the very wide lower riparian reach of the Muishond River at an oblique angle, which would result in a number of towers being likely to be required to be placed within the riparian corridor. The alignment of Corridor would allow the power line to be routed between the areas recommended to be avoided, not having to cross the Muishond River at this point. To the east of this point, all of the corridors traverse the hillier area of the Klein Roggeveld Mountains. This entails that rivers and watercourses are not characterised by extensively wide riparian corridors and are able to be singly spanned. There is thus very little difference between the corridors in this area, except at the fear eastern end of Corridor 1A, where Corridor 1 and 1A run parallel to the Buffels River for a 14km stretch, thus presenting potential issues for routing the power lines in relation to the riparian corridor of the river. Conversely Corridor 2 does not cross the Buffels River, rather traversing its upper catchment where a series of smaller tributaries are crossed.

As a result of the above, Corridor 2 is preferred from a surface water perspective in the section where all three alternatives are located.

Table 4 below lists the sensitive features and areas recommended to be avoided by the power line per corridor in the remainder of the route (comprising of only Corridors 1 and 2):

Table 4 – Comparative Assessment of Corridors1&2 in the remainder of the Study Areas Corridor Sensitive/ Prioritised Surface Areas to be avoided (large Water Features riparian areas) Corridor Alternative 1 26 19 Corridor Alternative 2 27 16

As is evident in Table 4, there is very little difference in number of Sensitive Surface Water Sites within the respective corridors. There is a marginally higher of areas recommended to be avoided (mostly wide and wooded riparian zones) within Corridor 1, in spite of the two corridor alternatives largely running closely in parallel to one another. The reason for this is that there are slightly more confluences of rivers within Corridor 1 as opposed to Corridor 2 and the lower reaches of the two respective rivers that drain to a confluence (in a Y shape) provide a single wider expanse of riparian habitat that would be impossible to singly span and which would require the clearing of large areas of woody vegetation. The area to the north-east of Beaufort West is also significant in differentiating between the two corridors; in this area a number of rivers drain the Nuweveld Mountain Range, draining into the flatter terrain to the south-east. Two of these rivers, the Kuils and Platdoring are characterised by very wide riparian corridors and in the case of the Platdorings River in Corridor 2, by extensive Vachellia karroo woodland across the riparian corridor. The Kuils River runs parallel to the corridor direction within Corridor 2 for a long distance but can be avoided by the line if it runs in the northern part of the corridor. However to the north-east of this the power line in Corridor 2 would need to cross the Platdoring and another wide riparian corridor of a tributary that span the entire corridor width. In Corridor 1 to the south a number of tributaries of the Platdoring drain together just to the north of the corridor and thus the line within this corridor could cross the lower reaches of the Platdoring over a shorter span. Accordingly Corridor 1 is preferred within this area.

There is a marginally higher number of areas recommended to be avoided and crossings in Corridor 1, but this does not constitute a fatal flaw in the overall context of the two corridors. The preference for Corridor 1 in the Platdorings area as discussed above is noted, however as Corridor 2 is preferred from a surface water perspective in the south-western part of the study area, Corridor 2 is marginally preferred along the remainder of the line Under ideal circumstances, the preference from a surface water perspective

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would be for the proposed power line to be aligned within Corridor 2 from the south-western part of the study area, crossing into Corridor 1 just west of Beaufort West where the two corridors overlap, thereby avoiding the crossing of the Platdorings system in Corridor 2 and it is proposed that such an option be explored to reduce surface water -related impacts.

9 Conclusions and Recommendations

The proposed power line alternative corridors traverse a large area and thus traverse a number of catchments and a large number of surface water features. The predominant surface water feature in the study area is the ephemeral river / drainage line, with only a very small number of the larger rivers being perennial or even seasonally flowing. This is due mainly to the semi-arid climate of the study area. Wetlands are very rare, only occurring in limited locations in the far south-west of the study area and in certain locations within the foothills of the Roggeveld Mountains south-east of Sutherland. A typical feature of the vast majority of surface features in the study area is the presence of a riparian zone that is distinct from the surrounding Karoo Shrubveld vegetation in terms of its structure and species composition. These riparian zones are ecologically very important and play an important role in terms of the morphological state and state of health of the watercourse along which they occur.

The proposed power line could result in a number of potential impacts on the identified surface water features in the area, which have been detailed above. Many surface water features and their associated riparian zones are sufficiently narrow in width to be able to be singly spanned by the proposed power lines. However there are many larger watercourses where the crossing length is wider than the typical power line span and where there the terrain is flat, entailing that riparian vegetation in the power line servitude would need to be cleared. In any event the practice of clearing of woody and other herbaceous vegetation from within the power line servitude no matter how narrow the riparian corridor would entail that most riparian areas would be likely to be affected through clearing. This would constitute an important cumulative impact on the riparian zone, especially in the context of the risk of further invasion of riparian corridors by alien invasive vegetation, as the clearing of woody vegetation offers highly favourable conditions for alien invasive plant encroachment. The impacts related to clearing of vegetation within the servitude have been identified as the most significant potential impact from a surface water perspective, especially when viewed in a cumulative impact context.

A number of generic and site-specific mitigation measures have been specified for the proposed project. The most important of these are ensuring that only woody vegetation larger than the minimum clearance height is felled and that certain areas recommended to be avoided by the power line within the corridors are avoided in routing the proposed power line. In addition it would be important to ensure that servitude management in terms of the clearing and management of alien invasive plants within the servitude be adhered to. These mitigation measures and recommendations must be followed / adhered to, to ensure that the impact of the proposed power lines on the surface water features in the study area is kept to a minimum.

From a surface water perspective, Corridor 2 is preferred from a surface water perspective in the section where all three alternatives are located, but it is recommended that the power line be routed along Corridor 1 in the vicinity of the Groot and lower Muishond River, and that the alignment then be moved northwards into Corridor 2. Corridor 2 is marginally preferred along the remainder of the line Under ideal circumstances, the preference from a surface water perspective would be for the proposed power line to be aligned within Corridor 2 from the south-western part of the study area, crossing into Corridor 1 just west of Beaufort West where the two corridors overlap, thereby avoiding the crossing of the Platdorings system in Corridor 2 and it is proposed that such an option be explored to reduce surface water -related impacts.

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10 References

◼ Basson, M. and Rossouw, J. (2003a). Fish to Tsitsikamma Water Management Area. Overview of Water Resources Availability and Utilisation. National Water Resource Strategy. BKS Report No H141415. DWAF Report No P WMA 15/000/00/0203.

◼ Department of Water Affairs and Forestry, 2005, A Practical field procedure for identification and delineation of wetlands and riparian areas, Final Draft

◼ Ewel, K.C., Cressa C., Kneib R.T., Lake P.S., Levin L.A., Palmer M.A., Snelgrove P. And Wall D.H., 2001. Managing Critical Transition Zones. Ecosystems 4, 452–460.

◼ Esler, K.J., Milton. S.J., and Dean, W.R.J. (eds.), 2010, Karoo Veld – Ecology and Management, Briza, Arcadia

◼ Holmes, P.M., Richardson, D.M., Esler, K.J, Witkowski, E.T.F., and Fourie, S., 2005, A decision-making framework for restoring riparian zones degraded by invasive alien plants in South Africa, South African Journal of Science 101, November/December 2005

◼ Holness, S. and Oosthuysen, E. 2016, Critical Biodiversity Areas of the Northern Cape: Technical Report.

◼ Institute for Water Research - Rhodes University, 2011, Implementing Uncertainty Analysis in Water Resources Assessment and planning. Water Research Commission Project No: K5/2056 - Deliverable No. 1: Design of surface – groundwater interaction studies

◼ Kleynhans, C.J., Mackenzie, J., Louw, M.D., 2007. Module F: Riparian Vegetation Response Assessment Index in River EcoClassification: Manual for EcoStatus Determination (version 2). Joint Water Research Commission and Department of Water Affairs and Forestry report. WRC Report

◼ Le Maitre, D.C., Scott, D.F., and Colvin, C., 1999. A review of information on interactions between vegetation and groundwater, Water SA Vol. 25 No. 2, April 1999

◼ Le Maitre, D.C., Maherry, A., Colvin, C., Prinsloo, E., Hughes, S., Smith-Adao, L. and Saayman, I., 2007. An overview of the hydrology, geohydrology and water resources of the Klein Karoo. Report No. CSIR/NRE/ECO/IR/2007/0010/A, Natural Resources and the Environment, CSIR, Stellenbosch.

◼ Le Maitre, D.C., O’Farrell, P., Milton, S.J., Atkinson, D., De Lange, W., Egoh, B., Reyers, B., Colvin, C., Maherry, A., and Blignaut., J., 2009. Assessment and Evaluation of Ecosystem Services in the Succulent Karoo Biome. Report prepared for the Succulent Karoo Ecosystem Programme (SKEP) Coordination Unit, SANBI

◼ Milton, S.J., 2010. Feasibility and benefits of veld rehabilitation following control of invasive Prosopis in the Calvinia area, Report prepared for Working for Water: Namakwa-District Municipality, Renu-Karoo Veld Restoration cc, PO Box 47 Prince Albert 6930 South Africa

◼ Mucina, L., & Rutherford, M.C., 2006. The Vegetation of South Africa, Lesotho and Swaziland, Strelitzia 19, South

◼ Ollis, D.J., Snaddon, C.D., Job, N.M. and Mbona, N. 2013. Classification System for Wetlands and other Aquatic Ecosystems in South Africa. User Manual: Inland Systems. SANBI Biodiversity Series 22. South African National Biodiversity Institute, Pretoria

◼ Palmer, A.R., and Hoffman, M.T., 1997. Nama-karoo. In: Cowling, R.M, Richardson, D.M., and Pierce, S.M. (eds.), Vegetation of Southern Africa, pp. 167–188. Cambridge University Press, Cambridge.

◼ Pool-Stanvliet, R., Duffell-Canham, A., Pence, G. & Smart, R. 2017. The Western Cape Biodiversity Spatial Plan Handbook. Stellenbosch: CapeNature

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◼ Rowntree, K.M. and Wadeson, R.A. 1999. A Hierarchical Geomorphological Model for the Classification of Selected South African Rivers. WRC Report No. 497/1/99, Water Research Commission, Pretoria, South Africa.

◼ Skowno, A.L., Holness, S.D., and Desmet, P., 2009. Biodiversity Assessment of the Central Karoo District Municipality. DEAP Report EADP05/2008, 52 pages

◼ Tang, S.M. and Montgomery, D.R., 1995. Riparian buffers and potentially unstable ground. Environmental Management. 19, 741–749.

◼ Van Oudtshoorn, F., 2004, Guide to Grasses of Southern Africa , Briza

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Appendix 1 - Impact Rating Methodology

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Table 1: Criteria and numerical values for rating environmental impacts Score Rating Description Intensity (I) – defines the magnitude of the impact Natural, cultural and social functions and processes are altered to extent that they permanently cease. Impact affects the continued viability of the systems / components and the quality, use, integrity and functionality of the systems / components permanently ceases and are irreversibly impaired (system collapse). Rehabilitation and remediation often impossible. If possible, rehabilitation and remediation often unfeasible due to extremely high costs of rehabilitation and remediation. 16 High Impact may cause: ▪ Loss of human life. ▪ Deterioration in human health. ▪ High impacts to ecosystems and environment resulting in: - Critical / severe local scale (or larger) modification / degradation and / or collapse. - Critical / severe local scale (or larger) modification (reduction in level) of ecosystem services and / or loss of ecosystem services. Natural, cultural and social functions and processes are altered to extent that they are severely impaired and may temporarily cease. Impact affects the continued viability of the systems/components and the quality, use, integrity and functionality of the systems / components are severely impaired and may temporarily cease. High costs of rehabilitation and remediation, but possible. Moderately 8 High Impact may cause: ▪ Loss of livelihoods. ▪ Individual economic loss. ▪ Moderately high impacts to ecosystems and environment: - Large local scale (or larger) modification / degradation and / or collapse. - Large local scale (or larger) modification (reduction in level) of ecosystem services and/or loss of ecosystem services. Affected environment is altered, but natural, cultural and social functions and processes continue albeit in a modified way. Impact alters the quality, use and integrity of the systems / components but the systems / components still continue to function but in a moderately modified way (integrity and functionality impaired but major key processes / drivers somewhat intact / maintained). 4 Moderate Moderate impacts to ecosystems and environment: ▪ Moderate local scale (or larger) ecosystem modification / degradation and / or collapse. ▪ Moderate local scale (or larger) modification (reduction in level) of ecosystem services and/or loss of ecosystem services. Affected environment is altered, but natural, cultural and social functions and processes continue albeit in a slightly modified way. Impact alters the quality, use and integrity of the systems / components but the systems / components still continue to function, although in a slightly modified way. Integrity, function and major key processes / drivers are slightly altered Moderately but are still intact / maintained. 2 Low Moderately low impacts to ecosystems and environment: ▪ Small but measurable local scale (or larger) ecosystem modification / degradation. ▪ Small but measurable local scale (or larger) modification (reduction in level) of ecosystem services and / or loss of ecosystem services. Impact affects the environment in such a way that natural, cultural and social functions and processes are not affected. 1 Low

Negative change to onsite characteristics but with no impact on:

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Score Rating Description ▪ Human life. ▪ Human health. ▪ Local water resources, local ecosystem services and / or key ecosystem controlling variables. ▪ Threatened habitat conservation / representation. ▪ Threatened species survival. Extent (E) – relates to the extent of the impact 5 Global The scale / extent of the impact is global / worldwide. 4 National The scale / extent of the impact is applicable to the Republic of South Africa. Impact footprint includes the greater surrounding area within which the site is located (e.g. 3 Regional between 20 - 200km radius of the site). Impact footprint extends beyond the cadastral boundary of the site to include the areas 2 Local adjacent and immediately surrounding the site (e.g. between a 0 - 20km radius of the site). 1 Site Impact footprint remains within the boundary of the site. Duration (D) – relates to the duration of the impact 5 Permanent The impact will continue indefinitely and is irreversible. The impact and its effects will continue for a period in excess of 30 years. However, the 4 Long-term impact is reversible with relevant and applicable mitigation and management actions. Medium- The impact and its effects will last for 10 - 30 years. The impact is reversible with relevant 3 term and applicable mitigation and management actions. The impact and its effects will continue or last for the period of a relatively long construction Medium- 2 period and / or a limited recovery time after this construction period, thereafter it will be short entirely negated (3 – 10 years). The impact is fully reversible. The impact and its effects will only last for as long as the construction period and will either 1 Short-term disappear with mitigation or will be mitigated through natural process in a span shorter than the construction phase (0 – 3 years). The impact is fully reversible. Probability (P) – relates to the likelihood of the impact occurring More than 75% chance of occurrence. The impact is known to occur regularly under similar 1 Definite conditions and settings. Highly The impact has a 41 - 75% chance of occurring and thus is likely to occur. The impact is 0.75 Probable known to occur sporadically in similar conditions and settings. The impact has a 10 - 40% chance of occurring. This impact may / could occur and is known 0.5 Possible to occur in low frequencies under the similar conditions and settings. The possibility of the impact occurring is low with less than 10% chance of occurring. The 0.2 Unlikely impact has not been known to occur under similar conditions and settings. The possibility of the impact occurring is negligible and only under exceptional 0.1 Improbable circumstances.

Significance is determined through a synthesis of impact characteristics. Significance is also an indication of the importance of the impact in terms of both physical extent and time scale, and therefore indicates the level of mitigation required. The total number of points scored for each impact indicates the level of significance of the impact.

Impact significance is expressed as the impact intensity, extent and duration against the probability/likelihood of the impact taking place (Table 2).

Impact significance = (impact intensity + impact extent + impact duration) x impact probability

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Table 2: Impact significance categories Class Description

+ Any value Any positive / beneficial ‘impact’, i.e. where no harm will occur due to the activity being undertaken. Low A low impact has no permanent impact of significance. Mitigation measures are feasible and are 0 - 4.9 readily instituted as part of a standing design, construction or operating procedure. Moderately Low Mitigation is possible with additional design and construction inputs. 5 – 7.9 The design of the site may be affected. Mitigation and possible remediation are needed during the Moderate construction and / or operational phases. The effects of the impact may affect the broader _ 8 – 12.9 environment. Generally unacceptable unless offset / compensated for by positive gains in other aspects of the environment that are of critically high importance (i.e. national or international importance only). Strict Moderately High conditions and high levels of compliance and enforcement are required. The potential impact will affect 13 – 17.9 a decision regarding the proposed activity and requires that the need and desirability for the project be clearly substantiated to justify the associated ecological risks. High Permanent and important impacts likely to be a fatal flaw. Impacts should be avoided and limited

18 - 26 opportunity for offset / compensatory mitigation. Status Denotes the perceived effect of the impact on the affected area. Positive (+) Beneficial impact. Negative (-) Deleterious or adverse impact. Neutral (/) Impact is neither beneficial nor adverse. It is important to note that the status of an impact is assigned based on the status quo – i.e. should the project not proceed. Therefore, not all negative impacts are equally significant.

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Appendix 2 - CV of Author

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Royal HaskoningDHV is an independent, international engineering and project management consultancy with over 138 years of experience. Our professionals deliver services in the fields of aviation, buildings, energy, industry, infrastructure, maritime, mining, transport, urban and rural development and water.

Backed by expertise and experience of 6,000 colleagues across the world, we work for public and private clients in over 140 countries. We understand the local context and deliver appropriate local solutions.

We focus on delivering added value for our clients while at the same time addressing the challenges that societies are facing. These include the growing world population and the consequences for towns and cities; the demand for clean drinking water, water security and water safety; pressures on traffic and transport; resource availability and demand for energy and waste issues facing industry.

We aim to minimise our impact on the environment by leading by example in our projects, our own business operations and by the role we see in “giving back” to society. By showing leadership in sustainable development and innovation, together with our clients, we are working to become part of the solution to a more sustainable society now and into the future.

Our head office is in the Netherlands, other principal offices are in the United Kingdom, South Africa and Indonesia. We also have established offices in Thailand, India and the Americas; and we have a long- standing presence in Africa and the Middle East.

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