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ESKOM DELMAS 44KV POWER LINE &
SUBSTATION PROJECT
Avifaunal Impact Assessment
12th September 2014
Compiled by: Submitted to:
WildSkies Ecological Services (Pty) Ltd Royal HaskoningDHV(Pty)Ltd
Luke Strugnell Sibongile Gumbi
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EXECUTIVE SUMMARY
Eskom Distribution is proposing to build a 44KV power line in the Delmas area. The proposed line will ‘T- off’
from an existing line and travel to the Botleng cemetery area where a new substation will be built on one of
two site alternatives. The proposed line will cross a wetland and as such a specialist avifaunal assessment was
conducted by Wildskies Ecological Services.
A site visit was conducted on the 4th September 2014 to assess the area and any micro-habitats that would be
an attractant for birds.
In total 12 Red List species were recorded in the broader area previously by the Southern African Bird Atlas
Project 1 and 2 (Harrison et al, 1994; and www.sabap2.adu.org.za), comprising 3 Endangered, 4 Vulnerable, 5
Near Threatened species (Taylor, 2014). There is also 1 Bonn listed species recorded as present in the broader
area. However the site itself is highly impacted on by human activities, and is in our opinion unlikely to be
important habitat for most Red List species.
The proposed power line and substation can be built with minimal impact on avifauna should the
recommendations in this report be followed. Alternative 3a or 3b should be used and these routes pose less
collision risk to birds and would therefore require a smaller section to be marked with anti-collision marking
devices. The relevant section has been highlighted in Figure 8.
The impact of electrocution is seen as being of low significance should the steel monopole be used. Should
this not be the case Wildskies Ecological Services must be consulted to reconsider this impact.
Habitat destruction is the most significant impact of this project and this must be mitigated for by staying out
of the wetland area as much as possible. The preferred alternatives must be used as this will further decrease
the impact on the wetland.
Disturbance of avifauna was considered to be negligible considering the background disturbance of this site.
From an ESKOM business perspective the steel monopole must be used as it is a very safe structure in terms
of bird induced faulting. It is envisaged that birds will undoubtedly use the new structure to perch on and to
mitigate for any potential problems the steel monopole is advised.
Should the recommendations in this report be followed the project will have an acceptable impact on
avifauna in the area.
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TABLE OF CONTENTS
DECLARATION OF INDEPENDENCE 4,5
1. INTRODUCTION
1.1. BACKGROUND 6
1.2. LIMITATIONS 8
1.3. LEGISLATION AND POLICY RELEVANT TO THIS ASSESSMENT 8,9
2. METHODS
2.1. LOCALITY 9
2.2. BIRD DATA 10,11,12
2.3. LAND USE 13
2.4. MICROHABITATS 14,15,16
3. RESULTS
3.1. COLLISIONS 17,18
3.2. HABITAT DESTRUCTION 19
3.3. ELECTROCUTIONS 19
3.4. DISTURBANCE 20
3.5. QUALITY OF SUPPLY 20
3.6. ASSESSMENT OF ALTERNATIVES
3.6.1. POWER LINE 20,21
3.6.2. SUBSTATION 21
4. CONCLUSION AND IMPACT STATEMENT 22
5. REFERENCES 23,24
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DECLARATION OF INDEPENDENCE
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.
Affiliation: South African Council for Natural Scientific Professions
Registration number: 400181/09
Fields of Expertise: Zoological Science
Registration: Professional Member
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 of.
» 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.
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» 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, 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 12th September 2014 by Luke Strugnell in his capacity as specialist investigator
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1. INTRODUCTION
1.1. Background
Eskom Distribution is proposing to build a 44KV power line in the Delmas area. The proposed line will ‘T- off’
from an existing line and travel to the Botleng cemetery area where a new substation will be built on one of
two site alternatives. The proposed line will cross a wetland and as such a specialist avifaunal assessment was
commissioned. This project was first assessed during 2009. More recently Wildskies Ecological Services were
appointed to conduct an updated assessment of the project.
A site visit was conducted on the 4th September 2014 to assess the area and any micro-habitats that would
be an attractant for birds.
In total 12 Red List species were recorded in the broader area previously by the Southern African Bird Atlas
Project 1 and 2 (Harrison et al, 1994; and www.sabap2.adu.org.za), comprising 3 Endangered, 4 Vulnerable,
5 Near Threatened species (Taylor, 2014). There is also 1 Bonn listed species present in the broader study
area. However the site itself is highly impacted on by human activities, and is in our opinion unlikely to be
important habitat for most Red List species.
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 electrocution of birds (and other animals) and birds colliding with
power lines (Ledger & Annegarn 1981; Ledger 1983; Ledger 1984; Hobbs & Ledger 1986a; Hobbs & Ledger
1986b; Ledger, Hobbs & Smith, 1992; Verdoorn 1996; Kruger & Van Rooyen 1998; Van Rooyen 1998; Kruger
1999; Van Rooyen 1999; Van Rooyen 2000). Other problems are electrical faults caused by bird excreta when
roosting or breeding on electricity infrastructure, (Van Rooyen & Taylor 1999) and disturbance and habitat
destruction during construction and maintenance activities.
Electrocution of birds is caused when a bird bridges the gap between either a live phase and an earth
component (phase-earth electrocution) or two live phases (phase-phase electrocutions). This type of impact
is a function of line design and the dimensions of a birds extremities. On the other hand, power lines have
proven to be partially beneficial to many birds, including species such as Martial Eagles Polemaetus bellicosus,
Tawny Eagles Aquila rapax, African White-backed Vultures Gyps africanus, and even occasionally Verreaux’s
Eagles Aquila verreauxii by providing safe nesting and roosting sites in areas where suitable natural
alternatives are scarce (van Rooyen 2004). Cape Vultures have also taken to roosting on power lines in certain
areas in large numbers (van Rooyen 2004a), while Lappet-faced Vultures are known to use power lines as
roosts, especially in areas where large trees are scarce (pers.obs.). Although this provision of nesting and
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roosting substrate can be beneficial, it could also simply place these birds at greater risk of collision with the
power lines.
Collision of birds: Collisions are the biggest single threat posed by the larger overhead lines to birds in
southern Africa (van Rooyen 2004). Most heavily impacted upon are bustards, storks, cranes and various
species of water birds. These species are mostly heavy-bodied birds with limited manoeuvrability, which
makes it difficult for them to take the necessary evasive action to avoid colliding with power lines (van Rooyen
2004, Anderson 2001). Data collected in the Northern Cape Province between 1997 and 1999 provides further
evidence of the gravity of the problem. During an initial clearing of transects, a total of 194 large bird
carcasses were found under 40km of Transmission line (220kV and 400kV) near De Aar in the Northern Cape.
Subsequent monitoring of 140 km of power lines (transects of 10km each from 22kV up to 400kV) in the same
area over a period of 12 months produced another 196 carcasses (mostly cranes and bustards).
The Red Data species vulnerable to power line collisions are generally long living, slow reproducing species
under natural conditions. Some require very specific conditions for breeding, resulting in very few successful
breeding attempts, or breeding might be restricted to very small areas. These species have not evolved to
cope with high adult mortality, with the result that consistent high adult mortality over an extensive period
could have a serious effect on a population’s ability to sustain itself in the long or even medium term. Many
of the anthropogenic threats to these species are non-discriminatory as far as age is concerned (e.g. habitat
destruction, disturbance and power lines) and therefore contribute to adult mortality, and it is not known
what the cumulative effect of these impacts could be over the long term.
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 levelling of substation yards. Servitudes have to be cleared 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 of the servitude through modification of
habitat.
Disturbance: Similarly, the above mentioned construction and maintenance activities impact on birds through
disturbance, particularly during the birds’ breeding activities.
Quality of supply of power lines by causing faults (short circuits): Birds are able to cause electrical faults on
power lines through various mechanisms such as bird streamers, bird pollution and bird nesting. The more
faults that occur on a line, the lower the quality of electrical supply to the end customers, which is not
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desirable from Eskom’s perspective.
1.2. Limitations
» The SABAP 1 data covers the period 1986-1997. The SABAP 2 data is more recent, and is collected on a
smaller spatial scale and is hence preferred for a study of this nature, where it is available.
» Predictions in this study are based on experience of these and similar species in different parts of South
Africa, through the authors’ experience since 2009. Bird behaviour cannot be reduced to formulas that
will hold true under all circumstances.
1.3. Legislation and policy relevant to this assessment
The relevant legislation to this specialist field and development include the following:
» The Convention on Biological Diversity (CBD) is dedicated to promoting sustainable development. The
Convention recognizes that biological diversity is about more than plants, animals and micro-organisms
and their ecosystems – it is about people and our need for food security, medicines, fresh air and water,
shelter, and a clean and healthy environment in which to live. It is an international convention signed by
150 leaders at the Rio 1992 Earth Summit. South Africa is a signatory to this convention, and any
development should consider its’ principles.
» An important principle encompassed by the CBD is the precautionary principle which essentially states
that where serious threats to the environment exist, lack of full scientific certainty should not be used a
reason for delaying management of these risks. The burden of proof that the impact will not occur lies
with the proponent of the activity posing the threat.
» The Convention on the Conservation of Migratory Species of Wild Animals (also known as CMS or Bonn
Convention) aims to conserve terrestrial, aquatic and avian migratory species throughout their range. It
is an intergovernmental treaty, concluded under the aegis of the United Nations Environment
Programme, concerned with the conservation of wildlife and habitats on a global scale. Since the
Convention's entry into force, its membership has grown steadily to include 117 (as of 1 June 2012) Parties
from Africa, Central and South America, Asia, Europe and Oceania. South Africa is a signatory to the CMS
and several relevant bird species could occur on the proposed site.
» The African-Eurasian Water bird Agreement. The Agreement on the Conservation of African-Eurasian
Migratory Water birds (AEWA) is the largest of its kind developed so far under the CMS. The AEWA covers
255 species of birds ecologically dependent on wetlands for at least part of their annual cycle, including
many species of divers, grebes, pelicans, cormorants, herons, storks, rails, ibises, spoonbills, flamingos,
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ducks, swans, geese, cranes, waders, gulls, terns, tropic birds, auks, frigate birds and even the South
African penguin. The agreement covers 119 countries and the European Union (EU) from Europe, parts
of Asia and Canada, the Middle East and Africa. Several of the bird species covered by the AEWA are
relevant to the proposed project.
» National Environmental Management – Biodiversity Act - Threatened Or Protected Species list (TOPS).
2 METHODS
2.1. Locality
Figure 1 shows the position and layout of the proposed project. Four alternative routes are presented for
the power line, and two alternative sites for the substation.
Figure 1- Map of the power line route alternatives with existing infrastructure (Map-Wildskies).
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2.2. Bird Data
Southern African Bird Atlas Project Data
Table 1 lists the Red List bird species recorded by the SABAP1 and SABAP2 (Harrison et al, 1997,
www.sabap2.adu.org.za) (the full species list is shown in Appendix 4). It is important to note that these
species occur in the greater Delmas area and not necessarily specifically on this site.
In total 12 Red List species were recorded in the area, comprising 3 Endangered, 4 Vulnerable, 5 Near
Threatened species (Taylor, 2014). There is also 1 Bonn listed species present in the study area.
Using this data in combination with the assessment of the micro habitats available to birds in the area – an
effective assessment of potential impacts of the proposed developments has been made as described below.
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Common Name Taxonomic Name SABAP1 SABAP2
Global Red List
Status_2013
Regional Red
List
Status_2014
Likelihood of
occuring on site Prefered Micro-habitat
Importance of
site for species Likely impacts
Harrier, Black Circus maurus X VU EN unlikely
fynbos and Karoo
areas of the Western
and Eastern Cape low
habitat
destruction
Stork, Yellow-billed Mycteria ibis X X LC EN unlikely
variety of
wetlands with shallow
water 10-40 cm deep
for feeding and
sandbanks or trees for
roosting low collision
Marsh-Harrier, African Circus ranivorus X X LC EN unlikely
breeds in wetlands,
foraging primarily over
reeds and lake margins low
habitat
destruction
Korhaan, White-bellied Eupodotis senegalensis X X LC VU possible
found in grassland and
open woodland habita
ts low collision
Falcon, Lanner Falco biarmicus X LC VU unlikely
inhabits a wide variety
of habitats, from
lowland deserts to
forested mountains, low collision
Secretarybird Sagittarius serpentarius X VU VU unlikely
found in grasslands,
ranging from open
plains to lightly
wooded savanna, but
is also found in
agricultural areas and
sub-desert low collision
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EN= Endangered; V=Vulnerable; NT=Near-threatened; Bonn=Protected Internationally under the Bonn Convention on Migratory Species.
Table 1. Red Data bird species recorded in the greater Delmas areas (within which the proposed power line is located Harrison et al, 1997).
Grass-Owl, African Tyto capensis X LC VU unlikely
grassland and
savannah low
habitat
destruction
Kingfisher, Half-collared Alcedo semitorquata X LC NT possible inland wetlands low
habitat
destruction
Pratincole, Black-winged Glareola nordmanni X X NT NT possible
It breeds on grazed
short-grass , fallow and
ploughed fields as well
as on alkaline flats,
sandspits, shell ridges
and sparsely
vegetated saltpans low
habitat
destruction
Duck, Maccoa Oxyura maccoa X X NT NT unlikely
small temporary and
permanent inland
freshwater lakes low
habitat
destruction
Flamingo, Lesser Phoenicopterus minor X X NT NT unlikely
The species breeds on
large undisturbed
alkaline and saline
lakes, salt pans or
coastal lagoons low collision
Flamingo, Greater Phoenicopterus ruber X X LC NT unlikely
The species inhabits
shallow eutrophic
waterbodies such as
saline lagoons,
saltpans and large
saline or alkaline lakes low collision
Stork, White Ciconia ciconia X X Bonn possible
The species inhabits
open areas, generally
avoiding regions with
persistent cold, wet
weather or large tracts
of tall, dense
vegetation such as
reedbeds or forests low collision
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2.3. Land use
The route was plotted on Google Earth to show the surrounding land use in the area and hence the habitat
available to birds.
Figure 2- Map of the power line route alternatives showing the human land use in the area. (Map-Wildskies).
As can be seen on the above map the area has a large degree of urbanisation as it is located just on the outskirts
of Delmas. There is also a great deal of informal hosing extending to the edge of the wetland. The area is
primarily used for subsistence agriculture including grazing of livestock. Unimproved grassland, cultivated
temporary- commercial dryland and urban land uses make up the area directly under the proposed new power
line. A large wetland also exists under the proposed line.
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2.4. Micro-Habitats
In terms of micro-habitats available for birds on site, the wetland is the only attractive micro-habitat, and will
attract a great deal of non-Red List species, these include herons, ducks, geese and Ibises. The extent to which
Red List species will frequent this area is relatively unknown, but in our opinion the likelihood of either large
numbers or frequent visits to the site by Red List species is low.
The site was visited to assess the route. Pictures of the study area can be seen below in Figures 3-7
Figure 3- Wetland running next to proposed line.
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Figure 4- Wetland in the study area.
Figure 5- “Pools” of surface water within the wetland.
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Figure 6- Informal housing next to wetland and in the study area
Figure 7- Substation sites.
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3 RESULTS
The results of the study have been detailed under the various impacts and the preferred alternatives are
discussed below.
3.1. Collisions
Collisions have been rated as the second highest impact of this proposed power line. This is due to the
wetland attracting many different species of birds. It is envisaged that the largest impact will occur on non-
Red List species. In order to mitigate for the impact of collisions it is strongly advised that the preferred
alternative route (see below) be used. Anti-collision marking devices must be fitted in accordance with
Eskom guidelines to the spans requiring marking (Figure 8 below.) These devices must be fitted on the earth
wire at the time of construction. It is recommended that a durable device be used and that it will be Eskom’s
responsibility to ensure that these line marking devices remain in working order for the full lifespan of the
power line, as we cannot afford to have significant numbers of bird collisions on this new line.
Should marking devices be fitted the impact of collision is seen as acceptable and the power line can be
built with minimal impact on avifauna.
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Figure 8- Spans that require anti-collision mitigation in the form of line marking (Map-Wildskies)
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3.2. Habitat Destruction
Habitat destruction has been rated as the highest impact for avifauna and this is due to the presence of the
wetland. Even though the general area is disturbed and degraded this wetland would still be a significant
attractant and habitat for birds. During the construction of the power line the possibility exists for this
wetland to be disturbed and habitat loss could result.
It is thus critically important that the preferred alternative be followed and that environmental best practice
be followed when it comes to building in or around the wetland. Where possible no new roads must be built
through the wetland and it is essential that no vehicles are driven into the area classified as wetland.
The impact of habitat destruction from building the substation is seen as minimal. The areas for the
proposed substation is both disturbed and degraded and the building of a substation on these sites will have
no major impact on avifauna.
If these guidelines are followed the impact is acceptable and the proposed project can be built with minimal
impact on avifauna.
3.3. Electrocutions
In order to rate the impact of electrocutions an assumption was made with regard to structural design of
the Eskom power line poles. It is assumed that a steel monopole will be used with the dimensions as per the
diagram in APPENDIX 1. If this is not the case the impact of electrocutions could be very different and
Wildskies Ecological Services must be consulted to re-evaluate this impact.
The steel monopole is generally a safe design for birds and the fitment of the standard bird perch further
increases this safety. The clearance of the conductors and earth wire all exceed 1.8m and this the impact of
electrocution is seen as low.
Electrocutions may occur in the substation during normal operation but the Red Data bird species in this
area are very unlikely to be affected by this as they are not known to frequent substations. There are
multiple places on substation hardware where birds could be electrocuted, and it is not considered worth
mitigating these proactively. If a problem is encountered once the substation is operational, reactive site
specific mitigation can be applied. This approach is considered acceptable due to the low risk to Red Data
or otherwise important bird species.
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Thus the impact of electrocutions is considered acceptable with the steel monopole design.
3.4. Disturbance
The impact of disturbance on avifauna is seen as very low in this area due to the already high levels of
background disturbance that exist in this area. This impact is therefore not discussed further in this report.
3.5 Quality of electrical supply
This is a business impact (not a conservation one) and depends on the pole design. As such this has been
rated on the assumption that the steel monopole design will be used. This is a generally safe design in terms
of faulting and as such this impact is insignificant and unlikely to occur. It must be noted that it would be to
ESKOMS advantage to use the steel monopole for this reason.
3.6. Assessment of alternatives
3.6.1. Power Line
Four alternatives exist and can be seen in Figure 1 above.
Alternative 1:
» This is the most westerly alternative and starts at the existing Delmas 44KV line.
» This line runs north but would run in the wetland for most of the way and cross it twice, this is
negative for avifauna both from a collision perspective and a habitat destruction perspective.
Alternative 2:
» This alternative starts at the existing Delmas 44KV line.
» This alternative is found slightly further east than alternative 1.
» This alternative crosses the wetland 3 times. This is a disadvantage to avifauna from a collision
perspective and a habitat destruction perspective.
Alternative 3a:
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» This alternative starts at the existing Delmas 44KV line and runs north on the eastern side of the
wetland.
» This alternative is less sensitive for avifauna as it is placed further from the wetland and only crosses
it once.
» Where the line does cross the wetland it does so at more of a perpendicular angle, which is
advantageous for avifauna as less length of power line impacts on the wetland than would be the
case with an oblique crossing.
Alternative 3b:
» Follows the same route as 3a but with a slight deviation.
» The deviation involves the line running further east, this is advantageous to avifauna as it places the
line further away from the wetland.
In order to rank these four alternatives a subjective rating (taking all of the above factors and field work
into account) was given between 1 and 5, with 5 being the most highly preferred and 1 being the least
preferred.
Alternative Preference rating
1 2
2 1
3a 5
3b 5
Table 2- Preference rating for the 4 line alternatives (5 is most highly rated and 1 is least highly rated for
avifauna)
As can clearly be seen above the preferred alternatives are alternative 3a and 3b. The main reason for this
is the fact that these alternative stay out of the wetland and thus the impact of habitat destruction will be
much less. The fact that these routes only crosses the wetland once is also an advantage and one that makes
financial sense too (as it will requires less line marking to mitigate collision risk).
3.6.2 Substation
There is no preference between the two sites in terms of avifauna and as such either may be used.
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4 CONCLUSION AND IMPACT STATEMENT
The proposed power line and substation can be built with minimal impact on avifauna should the
recommendations in this report be followed. Alternative 3a or 3b should be used and these routes pose less
collision risk to birds and would therefore require a smaller section to be marked with anti-collision marking
devices. The relevant section has been highlighted in Figure 8.
The impact of electrocution is seen as being of low significance should the steel monopole be used. Should
this not be the case Wildskies Ecological Services must be consulted to reconsider this impact.
Habitat destruction is the most significant impact of this project and this must be mitigated for by staying out
of the wetland area as much as possible. The preferred alternatives must be used as this will further decrease
the impact on the wetland.
Disturbance of avifauna was considered to be negligible considering the background disturbance of this site.
From an ESKOM business perspective the steel monopole must be used as it is a very safe structure in terms
of bird induced faulting. It is envisaged that birds will undoubtedly use the new structure to perch on and to
mitigate for any potential problems the steel monopole is advised.
Should the recommendations in this report be followed the project will have an acceptable impact on
avifauna in the area.
23
5 REFERENCES
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Van Rooyen, C.S. 2004a. 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. 2004b. Investigations into vulture electrocutions on the Edwardsdam-Mareetsane 88kV feeder, Unpublished report, Endangered Wildlife Trust, Johannesburg.
Van Rooyen, C.S. & 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) Verdoorn, G.H. 1996. Mortality of Cape Griffons Gyps coprotheres and African White-backed Vultures Pseudogyps africanus on 88kV and 132kV power lines in Western Transvaal, South Africa, and mitigation measures to prevent future problems. (2nd International Conference on Raptors: 2-5 October 1996. Urbino, Italy.)
25
APPENDIX 1-STRUCTURE OF THE PROPOSED POLE DESIGN – THE STEEL MONOPOLE
26
APPENDIX 2- TABLE OF IMPACTS
Nature: Collision of birds with overhead cables
Without mitigation With mitigation
Extent 2 2
Duration 4 4
Magnitude 3 2
Probability 3 2
Significance 27 (low) 16 (low)
Status Negative -
Reversibility Irreversible -
Irreplaceable loss of resources Yes- birds killed -
Can impacts be mitigated Yes -
Mitigation: Fit an approved Eskom marking device to the area specified in this report (Figure 8)
Cumulative impacts: Marginal
Residual impacts: Lifespan of the power line
27
Nature: Electrocution of birds (Assumption: use of steel monopole with dimensions as in
APPENDIX 1 Without mitigation With mitigation
Extent 1 1
Duration 4 4
Magnitude 2 2
Probability 1 1
Significance 7 (low) 7 (low)
Status Negative -
Reversibility Irreversible -
Irreplaceable loss of resources Yes birds killed -
Can impacts be mitigated Not required -
Mitigation: Not required
Cumulative impacts: Negligible
Residual impacts: Lifespan of the power line
28
Nature: Habitat destruction Without mitigation With mitigation
Extent 1 1
Duration 4 4
Magnitude 3 2
Probability 4 3
Significance 32 (medium) 21 (low)
Status Negative -
Reversibility Irreversible -
Irreplaceable loss of resources Yes-natural habitat -
Can impacts be mitigated Yes
Mitigation: The preferred route for the power line should be used. All construction and maintenance
activities should be carried out according to generally accepted environmental best practices. In particular,
care should be taken in the vicinity of the water bodies found within the study area. Existing roads must be
used as far as possible for access during construction.
Cumulative impacts: Marginal
Residual impacts: There will be a residual impact as habitat that is removed will not recover fully.
29
Nature: Disturbance of birds Without mitigation With mitigation
Extent 1 1
Duration 1 1
Magnitude 2 1
Probability 2 1
Significance 8 (low) 3 (low)
Status Negative -
Reversibility Irreversible -
Irreplaceable loss of resources No -
Can impacts be mitigated Yes -
Mitigation: Care should be taken to cause the least amount of disturbance necessary in order to build
and maintain the power line and substation.
Cumulative impacts: Negligible
Residual impacts: Slight
30
Nature: Faulting caused by birds – business impact Without mitigation With mitigation
Extent 1 1
Duration 4 4
Magnitude 0 0
Probability 1 1
Significance 5 (low) 5 (low)
Status Negative for business -
Reversibility Yes -
Irreplaceable loss of resources No -
Can impacts be mitigated Not necessary -
Mitigation: Pole design is enough, mitigation not required
Cumulative impacts: Negligible
Residual impacts: none
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APPENDIX 3- CRITERIA FOR EVALUATION OF IMPACTS
The following criteria were used to evaluate the significance of the anticipated impacts:
Extent of the impact: The extent of the impact was assessed accordingly:
· (1) Limited to the site and its immediate surroundings · (2) Local/Municipal extending only as far as the local community or urban area · (3) Provincial/Regional · (4) National i.e. South Africa · (5) Across International borders
Duration of the impact: The lifespan of the impact was assessed to be:
· (1) Immediate (less than 1 year) · (2) Short term (1-5 years) · (3) Medium term (6-15 years) · (4) Long term (the impact will cease after the operational life span of the project) · (5) Permanent (no mitigation measures of natural process will reduce the impact after
construction)
Magnitude of the impact: The magnitude or severity of the impacts is indicated as either:
· (0) None (where the aspect will have no impact on the environment) · (1) Minor (where the impact affects the environment in such a way that natural, cultural and
social functions and processes are not affected), · (2) Low (where the impact affects the environment in such a way that natural, cultural and
social functions and processes are slightly affected), · (3) Moderate (where the affected environment is altered but natural, cultural and social functions
and processes continue albeit in a modified way), · (4) High (where natural, cultural or social functions or processes are altered to the extent that it
will temporarily cease), or · (5) Very high / don’t know (where natural, cultural or social functions or processes are altered to
the extent that it will permanently cease).
Probability of occurrence: The likelihood of the impact actually occurring was indicated as either:
· (0) None (impact will not occur) · (1) Improbable (the possibility of the impact materializing is very low as a result of design, historic
experience or implementation of adequate mitigation measures)
32
· (2) Low probability (there is a possibility that the impact will occur) · (3) Medium probability (the impact may occur) · (4) High probability (it is most likely that the impact will occur) · (5) Definite / do not know (the impact will occur regardless of the implementation of any prevention
or corrective actions or it the specialist does not know what the probability will be based on too little published information)
Status of the Impact: The impacts are assessed as either having a:
· Negative effect (i.e. at a cost to the environment) · Positive effect (i.e. at a benefit to the environment) · Neutral effect on the environment.
Accumulative Impact: The impact of the development is considered together with additional developments of the same or similar nature and magnitude. The combined impacts may be:
· Negligible (i.e. the net effect is the same as a single development) · Marginal (i.e. the impact of the two developments of a similar nature is less than twice the impact
of a single development. This implies it is better to place the two developments in the same environment rather than in separate environments.
· Compounding (i.e. the impact of the two developments is more than twice the impact of two single developments. This implies that it is better to split the two developments into separate environments.
Significance of the Impact: Based on a synthesis of the information contained in the points above, the potential impacts were assigned a significance weighting (S). The weighting is formulated by adding the sum of the numbers assigned to extent (E), duration (D) and magnitude (M) and multiplying this sum by the probability (P) of the impact hence S=(E+D+M)P.
· Low (less than 30 points): the impact does not have a direct influence on the decision to
develop the area
· Medium (30-60 points): the impact could influence the decision to develop in the area unless it
is effectively mitigated
· High (above 60 points): where the impact must have an influence on the decision to proceed to
develop in the area
33
APPENDIX 4- FULL BIRD LIST FOR THE STUDY SITE – SABAP1 & 2
Number Common Name Taxonomic Name SABAP1 SABAP2
1 Avocet, Pied Recurvirostra avosetta X X
2 Babbler, Arrow-marked Turdoides jardineii X
3 Barbet, Black-collared Lybius torquatus X X
4 Barbet, Crested Trachyphonus vaillantii X X
5 Bee-eater, European Merops apiaster X
6 Bee-eater, White-fronted Merops bullockoides X
7 Bishop, Southern Red Euplectes orix X X
8 Bishop, Yellow Euplectes capensis X X
9 Bishop, Yellow-crowned Euplectes afer X X
10 Bittern, Little Ixobrychus minutus X
11 Bokmakierie, Bokmakierie Telophorus zeylonus X X
12 Boubou, Southern Laniarius ferrugineus X
13 Bulbul, Dark-capped Pycnonotus tricolor X X
14 Bunting, Cinnamon-breasted Emberiza tahapisi X
15 Buzzard, Steppe Buteo vulpinus X X
16 Canary, Black-throated Crithagra atrogularis X X
17 Canary, Cape Serinus canicollis X
18 Canary, Yellow Crithagra flaviventris X X
19 Canary, Yellow-fronted Crithagra mozambicus X X
20 Chat, Anteating Myrmecocichla formicivora X X
21 Cisticola, Cloud Cisticola textrix X X
22 Cisticola, Desert Cisticola aridulus X X
23 Cisticola, Levaillant's Cisticola tinniens X X
24 Cisticola, Pale-crowned Cisticola cinnamomeus X
25 Cisticola, Wailing Cisticola lais X
26 Cisticola, Wing-snapping Cisticola ayresii X X
27 Cisticola, Zitting Cisticola juncidis X X
28 Cliff-Swallow, South African Hirundo spilodera X X
29 Coot, Red-knobbed Fulica cristata X X
30 Cormorant, Reed Phalacrocorax africanus X X
31 Cormorant, White-breasted Phalacrocorax carbo X X
32 Coucal, Burchell's Centropus burchellii X X
33 Coucal, Burchells Centropus burchelli X
34 Coucal, White-browed Centropus superciliosus X
35 Crake, African Crecopsis egregia X
36 Crake, Black Amaurornis flavirostris X X
37 Crow, Cape Corvus capensis X
38 Crow, Pied Corvus albus X X
34
39 Cuckoo, Diderick Chrysococcyx caprius X X
40 Cuckoo, Red-chested Cuculus solitarius X X
41 Darter, African Anhinga rufa X X
42 Dove, Laughing Streptopelia senegalensis X X
43 Dove, Namaqua Oena capensis X X
44 Dove, Red-eyed Streptopelia semitorquata X X
45 Dove, Rock Columba livia X X
46 Drongo, Fork-tailed Dicrurus adsimilis X
47 Duck, African Black Anas sparsa X
48 Duck, Comb Sarkidiornis melanotos X X
49 Duck, Fulvous Dendrocygna bicolor X X
50 Duck, Maccoa Oxyura maccoa X X
51 Duck, White-backed Thalassornis leuconotus X X
52 Duck, White-faced Dendrocygna viduata X X
53 Duck, Yellow-billed Anas undulata X X
54 Eagle, Long-crested Lophaetus occipitalis X
55 Eagle-Owl, Spotted Bubo africanus X
56 Egret, Cattle Bubulcus ibis X X
57 Egret, Great Egretta alba X X
58 Egret, Little Egretta garzetta X X
59 Egret, Yellow-billed Egretta intermedia X X
60 Falcon, Amur Falco amurensis X X
61 Falcon, Lanner Falco biarmicus X
62 Finch, Cuckoo Anomalospiza imberbis X
63 Finch, Red-headed Amadina erythrocephala X X
64 Fiscal, Common Lanius collaris X X
65 Fish-Eagle, African Haliaeetus vocifer X
66 Flamingo, Greater Phoenicopterus ruber X X
67 Flamingo, Lesser Phoenicopterus minor X X
68 Flufftail, Red-chested Sarothrura rufa X
69 Flycatcher, Fiscal Sigelus silens X X
70 Flycatcher, Spotted Muscicapa striata X X
71 Francolin, Orange River Scleroptila levaillantoides X
72 Goose, Egyptian Alopochen aegyptiacus X X
73 Goose, Spur-winged Plectropterus gambensis X X
74 Grass-Owl, African Tyto capensis X
75 Grassbird, Cape Sphenoeacus afer X
76 Grebe, Great Crested Podiceps cristatus X X
77 Grebe, Little Tachybaptus ruficollis X X
78 Greenshank, Common Tringa nebularia X X
79 Guineafowl, Helmeted Numida meleagris X X
80 Gull, Grey-headed Larus cirrocephalus X X
35
81 Hamerkop, Hamerkop Scopus umbretta X X
82 Harrier, Black Circus maurus X
83 Harrier, Montagu's Circus pygargus X
84 Harrier-Hawk, African Polyboroides typus X
85 Heron, Black Egretta ardesiaca X
86 Heron, Black-headed Ardea melanocephala X X
87 Heron, Goliath Ardea goliath X X
88 Heron, Grey Ardea cinerea X X
89 Heron, Purple Ardea purpurea X X
90 Heron, Squacco Ardeola ralloides X X
91 Hoopoe, African Upupa africana X X
92 House-Martin, Common Delichon urbicum X
93 Ibis, African Sacred Threskiornis aethiopicus X X
94 Ibis, Glossy Plegadis falcinellus X X
95 Ibis, Hadeda Bostrychia hagedash X X
96 Jacana, African Actophilornis africanus X
97 Kestrel, Greater Falco rupicoloides X X
98 Kestrel, Lesser Falco naumanni X
99 Kestrel, Rock Falco rupicolus X X
100 Kingfisher, Giant Megaceryle maximus X
101 Kingfisher, Half-collared Alcedo semitorquata X
102 Kingfisher, Malachite Alcedo cristata X X
103 Kingfisher, Pied Ceryle rudis X X
104 Kite, Black-shouldered Elanus caeruleus X X
105 Korhaan, Black Eupodotis afra X
106 Korhaan, Blue Eupodotis caerulescens X
107 Korhaan, Northern Black Afrotis afraoides X
108 Korhaan, White-bellied Eupodotis senegalensis X X
109 Lapwing, African Wattled Vanellus senegallus X X
110 Lapwing, Blacksmith Vanellus armatus X X
111 Lapwing, Crowned Vanellus coronatus X X
112 Lark, Agulhas Clapper Mirafra marjoriae X
113 Lark, Cape Clapper Mirafra apiata X
114 Lark, Clapper Mirafra apiata X
115 Lark, Eastern Clapper Mirafra fasciolata X
116 Lark, Melodious Mirafra cheniana X
117 Lark, Pink-billed Spizocorys conirostris X
118 Lark, Red-capped Calandrella cinerea X X
119 Lark, Rufous-naped Mirafra africana X X
120 Lark, Spike-heeled Chersomanes albofasciata X X
121 Longclaw, Cape Macronyx capensis X X
122 Marsh-Harrier, African Circus ranivorus X X
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123 Martin, Banded Riparia cincta X
124 Martin, Brown-throated Riparia paludicola X X
125 Martin, Rock Hirundo fuligula X X
126 Masked-Weaver, Southern Ploceus velatus X X
127 Moorhen, Common Gallinula chloropus X X
128 Mousebird, Red-faced Urocolius indicus X X
129 Mousebird, Speckled Colius striatus X X
130 Myna, Common Acridotheres tristis X X
131 Neddicky, Neddicky Cisticola fulvicapilla X X
132 Night-Heron, Black-crowned Nycticorax nycticorax X X
133 Olive-Pigeon, African Columba arquatrix X
134 Ostrich, Common Struthio camelus X
135 Owl, Barn Tyto alba X X
136 Owl, Marsh Asio capensis X X
137 Palm-Swift, African Cypsiurus parvus X X
138 Paradise-Flycatcher, African Terpsiphone viridis X X
139 Pigeon, Speckled Columba guinea X X
140 Pipit, African Anthus cinnamomeus X X
141 Pipit, Buffy Anthus vaalensis X
142 Pipit, Plain-backed Anthus leucophrys X X
143 Plover, Common Ringed Charadrius hiaticula X
144 Plover, Kittlitz's Charadrius pecuarius X X
145 Plover, Three-banded Charadrius tricollaris X X
146 Pochard, Southern Netta erythrophthalma X X
147 Pratincole, Black-winged Glareola nordmanni X X
148 Prinia, Black-chested Prinia flavicans X X
149 Prinia, Tawny-flanked Prinia subflava X X
150 Quail, Common Coturnix coturnix X X
151 Quailfinch, African Ortygospiza atricollis X X
152 Quelea, Red-billed Quelea quelea X X
153 Rail, African Rallus caerulescens X
154 Reed-Warbler, African Acrocephalus baeticatus X X
155 Reed-Warbler, Great Acrocephalus arundinaceus X
156 Robin-Chat, Cape Cossypha caffra X X
157 Roller, Lilac-breasted Coracias caudatus X
158 Ruff, Ruff Philomachus pugnax X X
159 Rush-Warbler, Little Bradypterus baboecala X X
160 Sandpiper, Common Actitis hypoleucos X
161 Sandpiper, Curlew Calidris ferruginea X X
162 Sandpiper, Marsh Tringa stagnatilis X X
163 Sandpiper, Wood Tringa glareola X X
164 Secretarybird, Secretarybird Sagittarius serpentarius X
37
165 Seedeater, Streaky-headed Crithagra gularis X
166 Shelduck, South African Tadorna cana X
167 Shoveler, Cape Anas smithii X X
168 Shrike, Crimson-breasted Laniarius atrococcineus X
169 Shrike, Lesser Grey Lanius minor X X
170 Snake-Eagle, Black-chested Circaetus pectoralis X
171 Snipe, African Gallinago nigripennis X X
172 Sparrow, Cape Passer melanurus X X
173 Sparrow, Greyheaded Passer diffusus X
174 Sparrow, House Passer domesticus X X
175 Sparrow, Northern Grey-headed Passer griseus X
176 Sparrow, Southern Grey-headed Passer diffusus X X
177 Sparrow-Weaver, White-browed Plocepasser mahali X
178 Sparrowhawk, Little Accipiter minullus X
179 Sparrowhawk, Ovambo Accipiter ovampensis X
180 Sparrowlark, Chestnut-backed Eremopterix leucotis X X
181 Spoonbill, African Platalea alba X X
182 Spurfowl, Swainson's Pternistis swainsonii X X
183 Starling, Cape Glossy Lamprotornis nitens X X
184 Starling, Pied Spreo bicolor X X
185 Starling, Violet-backed Cinnyricinclus leucogaster X
186 Starling, Wattled Creatophora cinerea X X
187 Stilt, Black-winged Himantopus himantopus X X
188 Stint, Little Calidris minuta X X
189 Stonechat, African Saxicola torquatus X X
190 Stork, White Ciconia ciconia X X
191 Stork, Yellow-billed Mycteria ibis X X
192 Sunbird, Amethyst Chalcomitra amethystina X X
193 Swallow, Barn Hirundo rustica X X
194 Swallow, Greater Striped Hirundo cucullata X X
195 Swallow, Lesser Striped Hirundo abyssinica X
196 Swallow, Red-breasted Hirundo semirufa X
197 Swallow, White-throated Hirundo albigularis X X
198 Swamp-Warbler, Lesser Acrocephalus gracilirostris X X
199 Swamphen, African Purple Porphyrio madagascariensis X X
200 Swift, African Black Apus barbatus X
201 Swift, Alpine Tachymarptis melba X
202 Swift, Horus Apus horus X X
203 Swift, Little Apus affinis X X
204 Swift, White-rumped Apus caffer X X
205 Teal, Cape Anas capensis X X
206 Teal, Hottentot Anas hottentota X X
38
207 Teal, Red-billed Anas erythrorhyncha X X
208 Tern, Whiskered Chlidonias hybrida X X
209 Tern, White-winged Chlidonias leucopterus X X
210 Thick-knee, Spotted Burhinus capensis X X
211 Thick-knee, Water Burhinus vermiculatus X
212 Thrush, Karoo Turdus smithi X X
213 Thrush, Kurrichane Turdus libonyanus X
214 Thrush, Olive Turdus olivaceus X
215 Thrush, Olive Turdus olivaceus X
216 Turtle-Dove, Cape Streptopelia capicola X X
217 Wagtail, Cape Motacilla capensis X X
218 Warbler, Garden Sylvia borin X X
219 Warbler, Marsh Acrocephalus palustris X
220 Warbler, Sedge Acrocephalus schoenobaenus X
221 Warbler, Willow Phylloscopus trochilus X X
222 Waxbill, Common Estrilda astrild X X
223 Waxbill, Orange-breasted Amandava subflava X X
224 Weaver, Cape Ploceus capensis X X
225 Weaver, Thick-billed Amblyospiza albifrons X
226 Weaver, Village Ploceus cucullatus X
227 Wheatear, Capped Oenanthe pileata X X
228 White-eye, Cape Zosterops virens X X
229 White-eye, Cape Zosterops pallidus X
230 White-eye, Orange River Zosterops pallidus X
231 Whydah, Pin-tailed Vidua macroura X X
232 Widowbird, Fan-tailed Euplectes axillaris X X
233 Widowbird, Long-tailed Euplectes progne X X
234 Widowbird, Red-collared Euplectes ardens X
235 Widowbird, White-winged Euplectes albonotatus X X
236 Wood-Dove, Emerald-spotted Turtur chalcospilos X
237 Wood-Hoopoe, Green Phoeniculus purpureus X X
238 Woodpecker, Cardinal Dendropicos fuscescens X
239 Wryneck, Red-throated Jynx ruficollis X X
