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EWT-Avifaunal Specialist Report

KUDU DORSTFONTEIN 132KVSPECIALIST AVIFAUNAL ASSESSMENT

BA REPORT

Luke StrugnellEndangered Wildlife Trust011 [email protected]

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mailto:[email protected]


Specialist Investigator

The Natural Scientific Professions Act of 2003 aims to “Provide for the establishment of the South African Council of Natural Scientific Professions (SACNASP) and for the registration of professional, candidate and certified natural scientists; and to provide for matters connected therewith.”

“Only a registered person may practice in a consulting capacity” – Natural Scientific Professions Act of 2003 (20(1)-pg 14)

Investigator: Luke Strugnell (Pri.Sci.Nat)Qualification: BSc (hons) Zoology- Rhodes UniversityAffiliation: South African Council for Natural Scientific ProfessionsRegistration number: 400181/09Fields of Expertise: Zoological ScienceRegistration: Professional Member

Declaration of Independence

All specialist investigators specified above declare that: We act as independent specialists for this project. We consider ourselves bound by the rules and ethics of the South African Council For Natural

Scientific Professions. We do not have any personal or financial interest in the project except for financial

compensation for specialist investigations completed in a professional capacity as specified by the Environmental Impact Assessment Regulations, 2006.

We will not be affected by the outcome of the environmental process, of which this report forms part.

We do not have any influence over the decisions made by the governing authorities. We do not object to or endorse the proposed developments, but aim to present facts and our

best scientific and professional opinion with regard to the impacts of the development. We undertake to disclose to the relevant authorities any information that has or may have

the potential to influence its decision or the objectivity of any report, plan, or document required in terms of the Environmental Impact Assessment Regulations, 2006.

Should we consider ourselves to be in conflict with any of the above declarations, we shall formally submit a Notice of Withdrawal to all relevant parties and formally register as an Interested and Affected Party.

Terms and Liabilities

This report is based on a short term investigation using the available information and data related to the site to be affected. No long term investigation or monitoring was conducted.

The Precautionary Principle has been applied throughout this investigation. The specialist investigator, and the Endangered Wildlife Trust, for whom he/she works, does

not accept any responsibility for the conclusions, suggestions, limitations and recommendations made in good faith, based on the information presented to them by the lead consultant should this information be incorrect.

Additional information may become known or available during a later stage of the process for which no allowance could have been made at the time of this report.

The specialist investigator withholds the right to amend this report, recommendations and conclusions at any stage should additional information become available.

Information, recommendations and conclusions in this report cannot be applied to any other area without proper investigation.

This report and all of the information contained herein remain the intellectual property of the Endangered Wildlife Trust.

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This report, in its entirety or any portion thereof, may not be altered in any manner or form or for any purpose without the specific and written consent of the specialist investigator as specified above.

Acceptance of this report, in any physical or digital form, serves to confirm acknowledgment of these terms and liabilities.

Signed on the 22 November 2010 by Luke Strugnell in his capacity as specialist investigator for the Endangered Wildlife Trust’s Wildlife and Energy Programme.

EXECUTIVE SUMMARY

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In order to be able to adequately provide for the growing electricity demand, Eskom proposes to construct a new 132 KV line from the Kudu Substation to the proposed Dorstfontein substation. The structures proposed to be used for the 132 kV Sub-transmission line are the 132 kV steel monopole structures. These poles weigh approximately 1 200 kg each and vary in height from approximately 17, 4 m to 21 m. The size of the footprint depends on the suspension and angle strain pole used as bend / strain structures. The average span between two towers is 200 m, but can vary between 250 m and 375 m depending on the ground profile and the terrain to be spanned.

The self-supporting structure (suspension pole) is typically used along the straight sections of the power line, while the guyed intermediate or guyed suspension and angle strain structures are used where there is a bend in the power line alignment.

In terms of the EIA Regulations, feasible alternatives are required to be considered within the Basic Assessment Process. All identified, feasible alternatives are required to be evaluated in terms of social, biophysical, economic and technical factors.

This report forms the avifaunal specialist report for the project and the findings of the study are as follows:

The proposed project can go ahead with minimal impact on avifauna should the recommendations in this report be followed. It is highly recommended that alternative alignment 2 be used from an avifaunal perspective as this will result in the lowest collision risk as well as minimizing the impact of habitat destruction and disturbance. In addition the steel monopole design must be used as this will mitigate for the impact of electrocutions.

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1. INTRODUCTION & BACKGROUND

In order to be able to adequately provide for the growing electricity demand, Eskom proposes to construct a new 132 KV line from the Kudu Substation to the proposed Dorstfontein substation. The structures proposed to be used for the 132 kV Sub-transmission line are the 132 kV steel monopole structures. These poles weigh approximately 1 200 kg each and vary in height from approximately 17, 4 m to 21 m. The size of the footprint depends on the suspension and angle strain pole used as bend / strain structures. The average span between two towers is 200 m, but can vary between 250 m and 375 m depending on the ground profile and the terrain to be spanned.

The self-supporting structure (suspension pole) is typically used along the straight sections of the power line, while the guyed intermediate or guyed suspension and angle strain structures are used where there is a bend in the power line alignment.

In terms of the EIA Regulations, feasible alternatives are required to be considered within the Basic Assessment Process. All identified, feasible alternatives are required to be evaluated in terms of social, biophysical, economic and technical factors.

The EWT was appointed as the avifaunal specialist to work on this project and this report forms our avifaunal specialist report on the impacts that are to be expected with a project of this nature. A site visit was conducted on the 20th October 2010 to assess the area.

The relevant quarter degree square within which this project falls is 2629AB and five red data bird species have been recorded in this area by the South African Bird Atlas Project (SABAP). Of the red data species two are vulnerable, and three are near threatened. An additional two bird species are protected internationally under the Bonn convention.

In general terms, the impacts that could be associated with a project of this nature include: collision of birds with the overhead cables; electrocution of birds whilst perched on the tower structures; destruction of habitat; disturbance of birds; impact of birds on the power line performance through the streamer and pollution mechanisms and nesting on tower structures.

1.1 Description of proposed activitiesThe following are the proposed project activities:

Construction of a 132KV power line from Kudu substation to the proposed Dorstland substation.

Construction of a new Dorstland substation.

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Figure 1 . Study area layout showing existing infrastructure and line options (Map-EWT).

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2 GENERAL DESCRIPTION OF AVIAN INTERACTIONS WITH ELECTRICAL INFRASTRUCTURE

Because of their size and prominence, electrical infrastructures constitute an important interface between wildlife and man. Negative interactions between wildlife and electricity structures take many forms, but two common problems in southern Africa are the electrocution of birds (and other animals) and birds colliding with power lines. Other problems include: electrical faults caused by bird excreta when roosting or breeding on electricity infrastructure; and disturbance and habitat destruction during the construction and maintenance activities associated with electrical infrastructure.

2.1 Electrocution

Electrocution of birds on overhead lines is an emotional issue as well as an important cause of unnatural mortality of raptors and storks. It has attracted plenty of attention in Europe, USA and South Africa (APLIC 1994; van Rooyen and Ledger 1999). Electrocution refers to the scenario where a bird is perched or attempts to perch on the electrical structure and causes an electrical short circuit by physically bridging the air gap between live components and/or live and earthed components (van Rooyen 2004).

2.2 Collision

Collision is the biggest single threat posed by transmission lines to birds in southern Africa (van Rooyen 2004). Collision refers to the scenario where a bird collides with the conductors or earth wires of overhead power lines. This occurs because the birds cannot see the cables whilst in flight. Most heavily impacted upon are bustards, storks, cranes and various species of water birds. These species are mostly heavy-bodied birds with limited maneuverability, which makes it difficult for them to take the necessary evasive action to avoid colliding with power lines. Unfortunately, many of the collision sensitive species are considered threatened (Red Data status) in southern Africa. The Red Data species vulnerable to power line collisions are generally long living, slow reproducing species under natural conditions. These species have not evolved to cope with high adult mortality, with the result that consistently high adult mortalities over an extensive period could have a serious effect on a population’s ability to sustain itself in the long or even medium term. It is therefore imperative to reduce any form of unnatural mortality in these species, regardless of how insignificant it might seem at the present moment in time.

2.3 Habitat destruction

During the construction phase and maintenance of power lines and substations, some habitat destruction and alteration inevitably takes place. This happens with the construction of access roads, the clearing of servitudes and the leveling of substation yards. Servitudes have to be cleared

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of excess vegetation at regular intervals in order to allow access to the line for maintenance, to prevent vegetation from intruding into the legally prescribed clearance gap between the ground and the conductors and to minimize the risk of fire under the line which can result in electrical flashovers. These activities have an impact on birds breeding, foraging and roosting in or in close proximity to the servitude, through the modification of habitat.

2.4 Disturbance

During the construction and maintenance of electrical infrastructure, a certain amount of disturbance results. For shy, sensitive species this can impact on their usual daily activities, particularly whilst breeding.

2.5 Impact of the birds on the proposed power line

There are a number of mechanisms through which birds are able to cause electrical faults on power lines. In the case of a bird streamer induced fault, the fault is caused by the bird releasing a “streamer” of faeces which can constitute an air gap intrusion between the conductor and the earthed structure. Bird pollution is a form of pre-deposit pollution. A flashover occurs when an insulator string gets coated with pollutant, which compromises the insulation properties of the string. Bird nests may also cause faults through nest material protruding and constituting an air gap intrusion. Crows in particular often incorporate wire and other conductive material into their nests. When nests cause flashovers, the nesting material may catch fire. This in turn can lead to equipment damage or a general veld fire. Apart from the cost of replacing damaged equipment, the resultant veld fire can lead to claims for damages from landowners.

3 METHODOLOGY

3.1 Information sources used

The following information sources were consulted in order to conduct this study:

Bird distribution data of the Southern African Bird Atlas Project (SABAP – Harrison et al, 1997) was obtained for the quarter degree square which covers the study area, from the Avian Demography Unit of the University of Cape Town, as a means to ascertain which species occur within the study area.

The conservation status of all bird species occurring in the aforementioned quarter degree squares was determined with the use of The Eskom Red Data Book of Birds of South Africa, Lesotho and Swaziland (Barnes, 2000).

A classification of the vegetation types in the study area was obtained from (Mucina and Rutherford, 2006)

A classification of the land uses was obtained from the CSIR Google Earth was used to examine the study area.

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The location of the project in relation to the Important Bird Areas (IBA’s) was considered (Barnes, 1998) but it was found that the site does not occur within any IBA and thus not discussed further.

The alternative corridor alignments were visited and alternatives assessed in the field.

3.2. Assumptions and limitations

This study made the assumption that the above sources of information are reliable. The following factors may potentially detract from the accuracy of the predicted results:

The SABAP data covers the period 1986-1997. Bird distribution patterns fluctuate continuously according to availability of food and nesting substrate. For a full discussion of potential inaccuracies in SABAP data, see Harrison et al, 1997.

4. DESCRIPTION OF RECEIVING ENVIRONMENT

4.1. Vegetation and land use

It is widely accepted in ornithological circles that vegetation structure is more important in determining bird species abundance than vegetation species composition (in Harrison et al, 1997). Thus the land use and vegetation types were considered to determine what species may occur and where they are likely to occur.

The vegetation types present are discussed below and more importantly the land use practices can be seen in figure 2 below.

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Figure 2- Land use of the study area and the proposed line routes. (CSIR)

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The vegetation and land use maps were used in determining the preference of the corridors and the substation sites and they are thus discussed under these relevant sections below.

The vegetation is uniform on site , despite a few wetland vegetation patches, and is comprised of Eastern Highveld Grassland which is described as follows: “Slightly to moderately undulating plains, including some low hills and pan depressions. The vegetation is short dense grassland dominated by the usual Highveld grass composition with small, scattered rocky outcrops with wiry, sour grasses and some woody species.” ( Mucina and Rutherford, 2006, page 400). Perhaps more important than the vegetation classification, is an examination of the micro habitats available to birds. These are generally evident at a much smaller spatial scale than the vegetation types, and are determined by a host of factors such as vegetation type, topography, land use and man-made infrastructure.

The micro habitats identified in this study area are described below and can be seen in APPENDIX 1.

Grassland Patches: These open areas represent a significant feeding area for many bird species in densely populated areas. Specifically, these open grassland patches typically attract the storks and secretarybird. The low reporting rate for these species (TABLE 1 - Harrison et al 1997) is evidence of the impact that the surrounding developments are having on the birds that would, under optimum conditions, inhabit these open areas.

Wetlands, dams and watercourses: These can be very attractive micro habitats for birds as well as providing habitat for water birds etc. In this area species such as greater and lesser flamingoes may occur in areas around water. Non red data species may also occur in these areas for example herons.

Agricultural land: Arable or cultivated land represents a significant feeding area for many bird species in any landscape for the following reasons: through opening up the soil surface, land preparation makes many insects, seeds, bulbs and other food sources suddenly accessible to birds and other predators; the crop or pasture plants cultivated are often eaten themselves by birds, or attract insects which are in turn eaten by birds; during the dry season arable lands often represent the only green or attractive food sources in an otherwise dry landscape. The main species that are expected in these areas will include the storks and the secretarybird. The proposed power line will pass over or close to several areas of arable land.

Birds will, by virtue of their mobility, utilise almost any areas in a landscape from time to time. The final two columns in the Table 1 below represents each species’ most preferred or normal habitats and the likelihood of occurrence of these species in this study area. These locations are where most of the birds of that species will spend most of their time – and hence where impacts on those species will be most significant.

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4.2. Relevant bird populations

The relevant bird populations that have been reported by the South African Bird Atlas Project can be found below in Table 1. In addition the preferred habitat as well as likelihood of occurrence can be seen in the last two columns of the table.

Report rates are essentially an expression of the number of times a species was recorded in a square, as a percentage of the number of times that square was counted. A report rate of 0 means that the species was recorded in the square, but at a very low frequency. It is important to note that these species could have been recorded anywhere in the square, and not necessarily in the exact study area.

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Total Cards 86Total Species 160Total Breeding Species 30

NameConservation status 2629AB Habitat Likelihood of occurrence

Southern Bald (Bald) Ibis VU 1

High grassveld (especially after burning), heavily grazed pastures, cultivated lands; breeds in mountainous or highly dissected country Possible

Lesser Kestrel VU 3Open grassveld, mainly on highveld, usually near towns or farms Possible

Greater Flamingo NT 8Large bodies of shallow water, both inland and coastal; saline and brackish waters preferred Possible

Lesser Flamingo NT 1Larger brackish or saline inland and coastal waters Possible

Secretarybird NT 6Semidesert, grassland, savanna, open woodland, farmland, mountain slopes Possible

White Stork Bonn 9Highveld grasslands, mountain meadows, cultivated lands, marshes, karoo Likely

Abdim's Stork Bonn 1

Mainly highveld grassland; also semi-arid Kalahari (especially after rain), cultivated lands, inland waters Possible

VU=Vulnerable; NT= Near Threatened; Bonn= Protected under the Bonn ConventionTABLE 1- Red Data species report rates for the relevant quarter degree square which covers the study area (Harrison et al , 1997)

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5 EVALUATION OF IMPACTS

All of the impacts have been rated (Appendix 2) according to a defined methodology (Appendix 3). Below follows a more general discussion of the impacts as well as the mitigation measures for the various impacts.

5.1. Electrocutions

Electrocutions of sensitive species are most common on the actual power line poles and the risk of electrocution is directly related to the power line pole design. As the background information document proposes the use of the steel monopole it is unlikely that collisions will be a large impact. The steel monopole is generally a safe design provided that the standard dimensions are maintained. It is critically important that all phases and phase-earth clearances are greater than 1.8 meters. It is also important that the standard bird perch be used on these poles to provide a safe perching space for any birds wishing to perch on the power line.

Electrocutions in the proposed new substation could have an impact on birds but it is unlikely that the more sensitive species will utilize substations to perch or roost because of the disturbance related to the site. Substations can also be mitigated reactively fairly easily and as such if problems are encountered this can be done.

5.2. Collisions

Collisions are expected to be the largest impact of the proposed line, however sensitive species recorded by SABAP are not in great abundance in the area. Never the less mitigation measures should focus on minimizing the potential for this impact. The main mitigation measure will be the correct choice of line alternative and this is discussed below in the relevant section. In addition to this sensitive spans may require marking with anti collision marking devices to further mitigate for this impact. A map has been produced showing the areas that would require marking with anti-collision marking devices for the two feasible alternative. These areas are mainly dams, pans, rivers and canals. It is necessary to mark the entire section that crosses these areas as well as a span on either end. The map can be seen below in figure 3.

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Figure 3- Areas of the two feasible route alternatives that would require marking with anti-collision marking devices.

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5.3. Habitat destruction

Habitat destruction is unlikely to be a very significant impact in this area considering the existing levels of disturbance and habitat destruction. The greatest impact will be the construction of the substation and while this will result in total habitat destruction, the footprint and thus severity will be relatively small. Habitat destruction relating to the power line should not cause a significant impact in this area, as it is unlikely that large scale vegetation will have to be cleared. This is due to the fact that the vegetation is short and thus will not impact the power line. If the preferred alternative is chosen the impact of habitat destruction will be further decreased due to the presence of the existing servitude that can be used for access during building and maintenance activities. Additional mitigation measures should focus on preventing as much habitat destruction as possible. Existing roads must be used as well as the existing servitudes when constructing the new line.

5.4. Disturbance

As with the impact of habitat destruction, disturbance is unlikely to be a major impact in this area due to the existing levels of disturbance. Mitigation measures should focus on having the minimum amount of impact on the area during construction of the line and substation. Once again the existing servitude of the preferred alternative will help to reduce this impact to an acceptable level.

5.5. Faulting caused by birds

Since the steel monopole design has been proposed for use in this project it is unlikely that bird induced faulting will be a significant issue of the new line. The steel monopole is generally a safe design from a line performance perspective and thus this impact is not expected to be very significant. This will be the main mitigation measure for this impact.

6 COMPARISON OF ALTERNATIVES

6.1. Transmission line alternatives:

Three alternative alignments exist for this project, these have been described below:

Option 1: Starts at the Kudu substation next to the Komati power station. Most northerly alternative. Runs for 37.2km. Runs next to a decommissioned 88KV power line for the majority of the route. Runs next to an existing 88KV power line for the last half of the alignment. Runs over commercial dryland agriculture as well as unimproved grassland, also passes

close to two patches of forestry.

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Passes close to a few dams and wetlands as well as crosses one river, this is a disadvantage to avifauna as it increases the collision risk.

Option 2: Starts at the Kudu substation next to the Komati power station. Most southerly alternative. Runs for 20.3km. Runs near an existing 275KV power line for the majority of the alignment. Runs over commercial dryland agriculture and unimproved grassland as well as close to one

small patch of forestry. Crosses one river and passes close to some small dams and wetlands, this is negative for

avifauna as it increases the collision risk.

Option 3: Follows a very similar route to option 1 but takes a deviation towards the south after

approximately 20km and follows the R544 for 7km. Runs for 31.8km. Covers very similar habitat to option 1. Runs adjacent to the river for 5km, this is negative for avifauna as it increases the collision

risk.

In order to rank these alternatives a table was compiled and the three alternatives given a rating on a scale of 1 to 5, with 1 being the least preferred and 5 being the most highly preferred option.

Alternative Preference Rating1 32 53 2

It can clearly be seen in the above table that the preferred option is alternative 2 for the following reasons:

It is the shortest route and therefore has less of a collision risk. It runs near an existing 275KV line, this is a major advantage to avifauna if the new line is

placed as close as is legally possible to the existing line for the longest possible distance. This will result in double the visual signature to birds therefore decreasing the collision risk. An additional advantage is that the impact of habitat destruction and disturbance will be lower because of the existing access roads and servitude.

7 CONCLUSION

In conclusion the proposed project can go ahead with minimal impact on avifauna should the recommendations in this report be followed. It is highly recommended that alternative alignment 2

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be used from an avifaunal perspective as this will result in the lowest collision risk as well as minimizing the impact of habitat destruction and disturbance. In addition the steel monopole design must be used as this will mitigate for the impact of electrocutions.

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REFERENCES

AVIAN POWER LINE INTERACTION COMMITTEE (APLIC). 1994. Mitigating Bird Collisions with Power Lines: The State of the Art in 1994. Edison Electric Institute. Washington D.C.

ANDERSON, M.D. 2001. The effectiveness of two different marking devices to reduce large terrestrial bird collisions with overhead electricity cables in the eastern Karoo, South Africa. Draft report to Eskom Resources and Strategy Division. Johannesburg. South Africa.

BARNES, K.N. (ED.) 1998. The Important Bird Areas of Southern Africa. Birdlife South Africa, Johannesburg.

BARNES, K.N. (ED.) 2000. The Eskom Red Data Book of Birds of South Africa, Lesotho and Swaziland. BirdLife South Africa: Johannesburg.

CSIR , landcover data, CSIR Pretoria.

HARRISON, J.A., ALLAN, D.G., UNDERHILL, L.G., HERREMANS, M., TREE, A.J., PARKER, V AND BROWN, C.J. (EDS). 1997. The atlas of southern African birds. Vol. 1&2. BirdLife South Africa: Johannesburg.

MUCINA, L; RUTHERFORD, C. 2006. The Vegetation of South Africa, Lesotho and Swaziland, South African National Biodiversity Institute, Pretoria.

VAN ROOYEN, C.S. AND LEDGER, J.A. 1999. “Birds and utility structures: Developments in southern Africa” in Ferrer, M. & G..F.M. Janns. (eds.) Birds and Power lines. Quercus: Madrid, Spain, pp 205-230

VAN ROOYEN, C.S. 1998. Raptor mortality on power lines in South Africa. (5 th World Conference on Birds of Prey and Owls: 4 - 8 August 1998. Midrand, South Africa.)

VAN ROOYEN, C.S. 1999. An overview of the Eskom - EWT Strategic Partnership in South Africa. (EPRI Workshop on Avian Interactions with Utility Structures 2-3 December 1999, Charleston, South Carolina.)

VAN ROOYEN, C.S. 2000. “An overview of Vulture Electrocutions in South Africa.” Vulture News, 43, pp 5-22. Vulture Study Group: Johannesburg, South Africa.

VAN ROOYEN, C.S. 2003. Mitigation program for Avian Collisions with Eskom Transmission Lines. Unpublished Progress Report, September 2003. Endangered Wildlife Trust, Johannesburg, South Africa.

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VAN ROOYEN, C.S. 2004. The Management of Wildlife Interactions with overhead lines. In The fundamentals and practice of Overhead Line Maintenance (132kV and above), pp217-245. Eskom Technology, Services International, Johannesburg.

VAN ROOYEN, C.S. AND TAYLOR, P.V. 1999. Bird Streamers as probable cause of electrocutions in South Africa. (EPRI Workshop on Avian Interactions with Utility Structures 2-3 December 1999. Charleston, South Carolina)

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Appendix 1- Pictures from the site visit

Agricultural fields in the study area

Typical dams in the study area

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Typical dam and grassland in the study area

Existing Eskom servitude in the study area

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Appendix 2- Impact tables for the project

Electrocution Without Mitigation With MitigationTemporal Long Term Long termSpatial Localised LocalisedSeverity Moderately Severe SlightSignificance Moderate Low

Collision Without Mitigation With MitigationTemporal Long Term Long TermSpatial Localised LocalisedSeverity Moderately Severe SlightSignificance Moderate Low

Habitat Destruction

Without Mitigation With Mitigation

Temporal Permanent PermanentSpatial Localised LocalisedSeverity Moderately Severe SlightSignificance Moderate Low

Disturbance Without Mitigation With MitigationTemporal Short Term Short TermSpatial Localised LocalisedSeverity Moderately severe SlightSignificance Moderate Low

Faulting Without Mitigation With MitigationTemporal Permanent PermanentSpatial Localised LocalisedSeverity Moderately Severe SlightSignificance Moderate Low

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Appendix 3- Criteria used to rate the impacts

THE SIGNIFICANCE RATING SCALES – FOR THE EIA

1. Introduction

Although specialists are given free reign on how they conducted their research and obtained information, they are requested to provide the reports in a specific layout and structure, so that a uniform specialist report volume can be produced.

To ensure a direct comparison between various specialist studies, six standard rating scales are defined and used to assess and quantity the identified impacts. The rating system used for assessing impacts (or when specific impacts cannot be identified, the broader term issue should apply) is based on three criteria, namely:

The relationship of the impact/issue to temporal scales (Box 1.1);

The relationship of the impact/issue to spatial scales (Box 1.2); and

The severity of the impact/issue (Box 1.3).

These three criteria are combined to describe the overall importance rating, namely the significance (Box 1.4).

2. Temporal Scale

The temporal scale defines the significance of the impact at various time scales, as an indication of the duration of the impact.

Box 1.1: Temporal scale used in assessing issues.

Short term - less than 5 years. Many construction phase impacts will be of a short duration.

Medium term - between 5 and 15 years.

Long term - between 15 and 30 years

Permanent - over 30 years and resulting in a permanent and lasting change that will always be there.

3. Spatial Scale

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The spatial scale defines physical extent of the impact.

Box 1.2: Spatial scale used in assessing issues.

Individual - this scales applies to person/s in the area.

Household - this scales applies to households in the area.

Localised - small scale impacts- from a few hectares in extent to e.g. the local district area.

Regional – Provincial.

National - South Africa.

International – this scale applies outside of South Africa’s borders.

4. Severity/Beneficial Rating Scale

The severity scale is used in order to scientifically evaluate how severe negative impacts would be, or how beneficial positive impacts would be on a particular affected system or a particular affected party. It is a methodology that attempts to remove any value judgements from the assessment, although it relies on the professional judgement of the specialist.

Box 1.3: Severity/beneficial scale use in the EIA.

Very severe Very beneficial An irreversible and permanent change to the affected system(s) or party (ies) which cannot be mitigated. For example, the permanent change to topography resulting from a quarry.

A permanent and very substantial benefit to the affected system(s) or party(ies), with no real alternative to achieving this benefit. For example, the creation of a large number of long term jobs.

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Severe Beneficial

Long term impacts on the affected system(s) or party(ies) that could be mitigated. However, this mitigation would be difficult, expensive or time consuming or some combination of these. For example, the clearing of forest vegetation.

A long term impact and substantial benefit to the affected system(s) or party(ies). Alternative ways of achieving this benefit would be difficult, expensive or time consuming, or some combination of these. For example, an increase in the local

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economy. Moderately severe Moderately beneficial Medium to long term impacts on the affected system(s) or party (ies), that could be mitigated. For example constructing a narrow road through vegetation with a low conservation value.

A medium to long term impact of real benefit to the affected system(s) or party(ies). Other ways of optimising the beneficial effects are equally difficult, expensive and time consuming (or some combination of these), as achieving them in this way. For example a slight improvement in the (local) roads.

Slight Slightly beneficial Medium or short term impacts on the affected system(s) or party(ies). Mitigation is very easy, cheap, less time consuming or not necessary. For example, a temporary fluctuation in the water table due to water abstraction.

A short to medium term impact and negligible benefit to the affected system(s) or party(ies). Other ways of optimising the beneficial effects are easier, cheaper and quicker, or some combination of these. For example, a slight increase in the amount of goods available for purchasing.

No effect Don’t know/Can’t know The system(s) or party(ies) is not affected by the proposed development.

In certain cases it may not be possible to determine the severity of an impact.

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