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1
PRELIMINARY ECOLOGICAL ASSESSMENT
DELMAS NORTH SUBSTATION PROJECT;
NORTH WESTERN REGION,
ESKOM DISTRIBUTION DIVISION
Compiled for: Royal HaskoningDHV
BY:
Mr C.L.COOK Pr.Nat.Sci 400084/08 (MSc. Zool. U.P)
Ecological Consultant: Specialist Herpetological Consultant
Cell No. 082 688 9585
Giant. [email protected]
SUBMITTED: APRIL 2014
2
1. Background Information
Eskom Transmission is responsible for providing a high quality supply of
electricity to meet the ever increasing needs of its end users. As a result, its
infrastructure of power lines and substations are continuingly being
established and expanded upon to support annual load growth.
Delmas Municipal Council applied in March 2006 for a bulk supply of
electricity due to enlargement by one of the industrial customers as well as
increasing developments in the distribution license area. Eskom is planning
to build a complete 44/11kV1 x 20MVA substation at one of the two
alternative sites selected in the Delmas area (henceforth called the Demas
North Substation Site). The project will also involve the construction of
approximately a 5km single circuit lines (loop-in-configuration) from the
existing DS-SAR Dryden 44kV lines towards the new Delmas North
Substation (see figure 1 below for locality of the proposed line).
Eskom Holdings Limited has, in line with the EIA Regulations, appointed
Royal HaskoningDHV (RHDHV) as the independent consultant to undertake
the EIA for the proposed Delmas North Substation and loop-in-line located in
Delmas in the Mpumalanga Province. Royal HaskoningDHV (RHDHV) has
appointed Mr C.L. Cook to investigate the potential biophysical related
impacts associated with the construction of the Delmas North Substation as
well as the proposed ±5km circuit line.
It must be stressed that due to time as well as financial constraints no
comprehensive vegetation or faunal surveys were conducted; but merely a
brief assessment of the current ecological status of the proposed substation
sites as well as loop-in-alignments. By surveying the actual site as well as
immediate habitats adjacent to the proposed site for specialised habitats, as
well as the remaining vegetation and specific habitats, one can make an
assumption of the possible presence or absence of threatened plant and
animal species. The survey was supplemented by literature investigations;
personal records, historic data and previous surveys conducted in the
Delmas-Nigel areas as well as in similar habitats from 1999-2014.
3
The purpose of this document is to highlight potential impacts on the
biodiversity of the project from a potential faunal and vegetation perspective.
Special emphasis was placed on the potential occurrence of Red Listed/Data
plant and animal species likely to occur in the areas of the proposed
alternative substation sites as well as the 5km loop-in-line.
1.1 Objectives of the initial ecological survey/ habitat
assessment
• To provide a description of the vegetation as well as threatened
mammals, birds, reptiles and amphibians occurring or likely to occur
on the proposed sub-station site as well as along the circuit line
alignments.
• To describe the available habitats on site including areas of important
conservation value or areas most likely to form important habitat for
remaining threatened species on or around the proposed sub-station
sites as well as along the circuit line alignments.
1.2 Scope of study
• A preliminary ecological survey with special emphasis on the current
status of threatened plant and animal species (Red Data Species),
within the proposed substation sites as well as along the circuit line
alignments.
• An assessment of the ecological habitats, evaluating conservation
importance and significance with special emphasis on the current
status of threatened animal species (Red Data Species), within the
proposed substation sites as well as along the circuit line alignments.
Identification of potential ecological impacts that could occur as a
result of the Delmas substation and circuit line and assess the
significance of these, where possible.
• Investigate feasible and practical management recommendations that
should be implemented to reduce or minimize the impacts, should the
project be approved
• Documentation of the findings of the study in a report.
4
Figure1. Locality map of proposed Delmas North Substation sites as well as
circuit alignments.
5
2. METHODOLOGY
2.1 Predictive methods
A 1:50 000 map of the study area was provided showing existing
infrastructure and the proposed alignments. This was used as far as
possible in order to identify potential “hot-spots” along the corridors, e.g.
Patches of undisturbed grassland vegetation, river crossings, palustrine
wetlands (valley bottoms, pans/depressions and hillslope seeps), dams
and agricultural areas. Satellite imagery of the area was obtained from
Google Earth was studied in order to get a three dimensional impression
of the topography and land use.
2.2 Literature Survey
A detailed literature search was undertaken to assess the current status of
threatened fauna that have been historically known to occur in the study
area for the 2628 BA quarter degree grid cell (or 1: 50 000 map unit),
within which the alignments are located. The literature search was
undertaken utilising The Vegetation of South Africa, Lesotho and
Swaziland (Mucina & Rutherford 2006) for the vegetation description as
well as National Red List of Threatened Plants of South Africa (Raimondo
et al, 2009) as well as internet using POSA (http://posa.sanbi.org
accessed on the 31st March 2014). The Mammals of the Southern African
Subregion (Skinner & Chimimba 2005) and The Red Data Book of the
Mammals of South Africa: A Conservation Assessment (Friedmann and
Daly (editors) 2004) as well as ADU’s MammalMap
(http://vmus.adu.org.za/vm_sp_list.php accessed on the 31st of March
2014) for mammals. Hockey, P.A.R., Dean, W.R.J., Ryan, P.G. (eds).
2005. Roberts- Birds of Southern Africa VIIth ed. And BARNES, K.N. (ed.)
(2000) The Escom Red Data Book of Birds of South Africa, Lesotho and
Swaziland for avifauna (birds) as well as internet SABAP2 pentad 2420-
3055 (http://sabap2.adu.org.za accessed on the 31st March 2014). The
Atlas and Red Data Book of the frogs of South Africa, Lesotho and
Swaziland (Minter et al. 2004) for amphibians as well as SAFAP FrogMap
(http://vmus.adu.org.za accessed on the 31st March 2014) The Field
Guide to the Snakes and other Reptiles of Southern Africa (Branch 2001)
and South African Red Data Book-Reptiles and Amphibians (Branch 1988)
as well as SARCA (http://sarca.adu.org.za accessed on the 31st March
2014) for reptiles..
6
2.3 Site Investigation Methodology
A preliminary assessment of the status, spatial requirements and habitat
preferences of all priority species around the proposed substation site as
well as along the proposed circuit line as well as potential threats to
adjacent sensitive habitats was conducted. For certain species, an
estimate of the expected or historical distribution for the area could be
extrapolated from published information and unpublished reports, while
habitat and spatial requirements were generally derived from the
literature. For other species, little of this information was readily available
and conservation targets remain speculative. Species assessments will be
updated when additional data becomes available and where appropriate,
proposed conservation targets will be revised.
Three general habitat sensitivity scans were carried out on the 14th of
March 2009; 14th of April 2009 and the 21st March 2014. . These site visits
did not entail intensive surveying or utilisation of any sampling methods
and can rather be viewed as being an opportunity to identify sensitive
habitats at the proposed Delmas substation as well as along the circuit
line alignment.
2.4 Uncertainties in predicting results
• Limitation to a base-line ecological survey for only 3 days (20
hours) during the late summer months (March-April).
• No comprehensive vegetation or faunal surveys were conducted
but merely a preliminary ecological assessment.
• The majority of threatened plant and animal species are
seasonal only emerging after sufficient early heavy summer
rainfalls between October and December.
• The majority of threatened faunal species are extremely
secretive and difficult to observe even during intensive field
surveys conducted over several years.
• The presence of threatened species on site is assessed mainly
on habitat availability and suitability as well as desk research
(literature, personal records and previous surveys conducted in
similar habitats between1999-2014).
7
2.5 Gaps in the baseline data
• Little long-term, verified data of faunal species distribution on
micro-habitat level along the proposed powerline alignment.
• Little long-term, verified data on impacts of existing lines (bird-
collisions etc.) in the study area on fauna.
3. DESCRIPTION OF THE AFFECTED
ENVIRONMENT
3.1 Vegetation and Faunal habitat Availability
Vegetation structure is generally accepted to be more critical in
determining faunal habitat than actual plant composition. Therefore, the
description of vegetation presented in this study concentrates on factors
relevant to faunal species abundance and distribution, and does not give
an exhaustive list of plant species which occur in the study area.
The study area falls within the 2628 BA quarter degree grid cells.
Vegetation composition in the area consists of a transitional zone between
Eastern Highveld Grassland (Gm 12) as well as Rand Highveld
Grassland (Gm 11) (Mucina & Rutherford 2006). The majority of the line
and the proposed substation sites are situated within the Eastern
Highveld (Gm 12) vegetation unit with a section of alternative 2 and 3
alignments bisecting highly degraded Rand Highveld Grassland (Gm
11) previously classified as Bankenveld (Acocks 1988) or Rocky
Highveld Grassland (45%), Sandy Highveld Grassland (LR 38) (Low
& Rebelo 1995).
8
Figure2. Vegetation units of proposed Delmas North Substation and
circuit line.
9
3.2 Eastern Highveld Grassland (Gm 12)
Vegetation & Landscape Features:
Characterised by short dense grass dominated by the usual highveld grass
composition (Aristidia, Digitaria, Eragrostis, Themeda, Tristachya etc) with
small rocky outcrops with wiry, sour grasses and some woody species
(Acacia caffra, Celtis africana, Diospyros lycioides subs lyciodes, Parina
capensis, Protea caffra, P. welwithchii and Searsia magaliesmontanum)
(Mucina & Rutherford 2006).
Distribution: Eastern Highveld Grassland (Gm 12) is distributed in
Mpumalanga and Gauteng Province on the plains between Belfast in the
east and the eastern side of Johannesburg in the west and extending
southwards to Bethal, Ermelo and west of Piet Retief (Mucina & Rutherford
2006).
.
Geology and Soils: Eastern Highveld Grassland or Sour grassland
generally occurs in high rainfall areas on leached soils. The predominant
rock types are shales and sandstones of the Vryheid and Volksrust
Formations (Ecca Group, Karoo Sequence), giving rise to deep, red to
yellow, sandy soils (Mucina & Rutherford 2006).
.
Climate: Strongly seasonal summer-rainfall region, warm temperatures
with very dry winters. Mean annual precipitation ranges between 650-900
mm (overall MAP 726 mm) and relatively uniform across most of this unit,
but increases significantly in the extreme southeast. The incidence of frost
is from 13-42 days but higher at higher elevations (Mucina & Rutherford
2006).
Conservation:
Eastern Highveld grasslands are considered to be Endangered and are
very suitable for crop production, with the natural vegetation heavily used
for grazing of sheep and cattle. Approximately 44% has been transformed
by cultivation, plantations, mines, urbanization and by the building of
dams. The conservation status of this vegetation type is very poor. Moist
Sandy Highveld Grassland is now largely ploughed, with natural
vegetation restricted to patchy remnants, which are often heavily grazed.
The Nooitgedacht Dam Nature Reserve is the only official conservation
area of this vegetation type, but the Ermelo Game Park represents a good
example of this vegetation type (Bredenkamp & van Rooyen, 1996).
10
Vegetation
Type
Eastern Highveld Grassland
(Gm 12)
Tree cover
0 %
Soil Light brown sandy soils as
well as sandy-loams
Shrub cover 0 %
Topography Undulating Plain Herb cover
(weedy
pioneers)
0-10 %
Land use Road & powerline
servitudes (Illegal dumping
activities)
Grass cover 0-90 %
Dominant
Grasses
Hyparrhenia hirta, Setaria sphacelata, Erogrostis curvula,
Setaria sphacelata, Melinis repens, Aristida congesta,
Heteropogon contortus, Cynodon dactylon and
Hyperthelia dissoluta
Dominant
Herb
Species
Hypoxis acuminata, Ledebouria ovatifolia
Alien
Invasive
Species
Argemone ochroleuca subsp. ochroleuca*, Solanum
sisymbrifolium*, Datura stramonium*, Robinia
pseudoacaia*, Ipomoea purpurea*, Lantana camara*,
Ricinus communis*, Solanum mauritianum*
11
Figure3. A collage of photographs displaying the transformed
Eastern Highveld grasslands observed within the proposed
substation sites and circuit alignments A: The proposed substation
alternative site 1 is situated within a completely transformed and
degraded vegetation unit and have been heavily impacted on by adjacent
informal settlements. Extensive illegal dumping activities occur adjacent
to the informal access road. B: The alternative 2 substation site is situated
within transformed Hyparrhernia hirta grasslands. C & D: The proposed
circuit alignments follow an existing access road as well as existing
powerline and sewerage alignments dominated by completely transformed
vegetation and habitats.
The grasslands have been impacted on by anthropomorphic activities
during previous agricultural activities as well as current human activities.
Large areas of the proposed development area consists of homogenous
transformed old agricultural/fallow lands dominated by the
anthropomorphic grass Hyparrhenia hirta as well as several weedy plant
species such as Zinnia peruviana, Mirabilis jalapa, Tagetes minuta, Bidens
pilosa, Cosmos bipinnatus, Conyza albida as well as the secondary
succession grass Eragrostis curvula, E. chloromelas and Cynodon
dactylon.
12
3.3 Rand Highveld Grassland (Gm 11)
Vegetation & Landscape Features:
Highly variable landscapes with extensive sloping plains and series of
ridges slightly elevated over undulating surrounding plains. The vegetation
is species-rich, wiry, sour grassland alternating with low, sour shrubland
on rocky outcrops and steeper slopes. Most common grasses on the plains
belong to the genera Themeda, Eragrostis, Heteropogon and Elionurus.
High diversity of herbs, many of which belong to the Asteraceae, is also a
typical feature (Mucina & Rutherford 2006).
Distribution: Gauteng, North-West, Free State and Mpumalnaga
Provinces. In areas between rocky ridges from Pretoria to Witbank,
extending onto ridges in the Stoffberg and Roosenekal regions as well as
Krugersdorp centered in the vicinity of Derby and Potchestroom,
extending southwards and north-eastwards from there (Mucina &
Rutherford 2006)..
Geology and Soils: Rand Highveld Grassland occurs on the Quartzite
ridges of the Witwatersrand Supergroup and the Pretoria Groups as well
as the Selons River Formation of the Rooiberg Group, supporting soils of
various quality (shallow Glenrosa and Mispah forms especially on rocky
ridges), typical Ba, Bc, Bd and lb land types.
Climate: Strongly seasonal summer-rainfall region, warm temperatures
with very dry winters. Mean annual precipitation (MAP 654 mm). The
incidence of frost is higher in the west (30-40 days) than in the east (10-
35 days). Temperatures vary between 0°C and 30°C, with an average of
15.8°C.
Conservation: Rand Highveld grasslands are considered to be
Endangered. The conservation target is 24%. Only 1 % is statutorily
conserved (Kweaggavoetpad, Van Riebeeck Park, Bronkhorstspruit,
Boskop Dam Nature Reserve) and in private conservation areas
(Doornkop, Zemvelo, Rhenosterpoort and Mpopomeni). Almost half has
been transformed mostly by cultivation, plantations, urbanisation or dam
building. Cultivation may also have had an impact on additional portion of
the surface area of the unit where old lands are currently classified as
grasslands in land-cover classifications and poor land management has led
to degradation of significant portions of the remainder of this unit (D.
Hoare, personal observations).
13
Vegetation
Type
Rand Highveld Grassland
(Gm 11)
Tree cover
0 %
Soil Light brown sandy soils as
well as sandy-loams
Shrub
cover
0 %
Topography Low lying quartzite ridge Herb
cover
0-10 %
Land use Vacant (cattle grazing) Grass
cover
0-80 %
Dominant
Grasses
Hyparrhenia hirta, Setaria sphacelata, Erogrostis curvula,
Melinis repens, Aristida congesta, Heteropogon contortus,
Cynodon dactylon and Hyperthelia dissoluta
Dominant
Herb
Species
Babiana hypogea var. hypogea, Hypoxis rigidula,
Ledebouria ovatifolia, Ledebouria revolute, Trifolium
africanum var. africanum, Seriphium plumosum,
Pseudognaphalium luteo-album*
Alien
Invasive
Species
Agave americana*, Argemone ochroleuca subsp.
ochroleuca*, Solanum sisymbrifolium*, Campuloclinium
macrocephalum*, Ricinus communis*, Solanum
mauritianum*, Cirsium vulgare∗, Pennisetum
clandestinum*
∗ alien invasive vegetation
14
Figure4. A collage of photographs displaying the transformed and
degraded Rand Highveld grasslands observed within the proposed
substation sites and circuit alignments A: The proposed circuit
alignment is situated within transformed and degraded grassland
vegetation units and have been heavily impacted on by adjacent informal
settlements. B: A patch of quartzite extrusions or ridge occurs on a low-
lying ridge adjacent to the channelled valley bottom. C: The entire area
has been heavily impacted on by extensive overgrazing by cattle and
goats hence the dominance of the dwarf shrublet Bankrupt Bush
Seriphium plumosum/Stoebe vulgaris, harvesting of traditional medicinal
plants and grasses as well as altered fire regimes (more frequent fires).
D: Several alien invasive plant species including Kikuyu Pennisetum
clandestinum*, Pom-Pom Weed Campuloclinium macrocephalum* and
Sisal Agave americana* were observed along the proposed alignments.
15
3.4 RED LISTED PLANT SPECIES CONCLUSION
From a faunal and vegetation perspective both the proposed substation
sites are situated within transformed habitats and vegetation units. The
alternative 1 is the slightly preferred option as the alternative 2 site is
situated adjacent to a degraded seepage wetland. Both are however
situated in transformed grassland habitats with low sensitivity and low
conservation potential.
Remnant patches of degraded Rand Highveld Grassland occur around the
rocky hills adjacent to a channelled valley bottom as well as areas to the
north of the proposed line. The vegetation has been heavily impacted on
by overgrazing of livestock, frequent fires, harvesting of traditional
medicinal plants and alien vegetation invasion. The majority of Eastern
Highveld Grassland along and surrounding the alignments has been
completely transformed due to the large informal settlements and high
levels of human disturbances, previous and current agricultural activities
in the area and are dominated by weedy ruderals and pioneer species
such as Redstar Zinnia Zinnia peruviana*, Common Thorn Apple Datura
stramonium*, Black Jacks (Bidens pilosa), Khaki Bush (Tagetes minuta)
and Cosmos (Cosmos bipinnatus). The secondary succession grasslands
are severely degraded due extensive overgrazing, frequent fires,
harvesting of medicinal plants as well as invasion by alien plant and tree
species. The majority of tree species found along the alignments are
exotics as well as alien invasive species such as Eucalyptus sp., Acacia
mearnsii, Robinia pseudoacacia. Patches of secondary grasslands (old
agricultural lands) are situated along the proposed alignments. Alternative
1 and 2 run parallel to the degraded channelled valley bottom which is
dominated by hydrophilic grasses and sedges as well as pioneer weedy
plant species.
16
Table1. Red listed plant species recorded from the 2628 BA Quarter
Degree Grid Cell (SANBI, POSA Website http://posa.sanbi.org
downloaded on the 9th of April 2014)
FAMILY SPECIES STATUS HABITAT PROBABILITY
OF OCCURRENCE
AMARYLLIDACEAE Crinum
bulbispermum
Declining
Near rivers,
streams,
seasonal
pans and in
damp
depressions.
Low
APOCYNACEAE Stenostelma
umbelluliferum
Near
Threatened
Deep black
turf in open
woodland
mainly in
the vicinity
of drainage
lines.
Pretoria into
North-West
Province.
None
ASPHODELACEAE Kniphofia
typhoides
Near
Threatened
Low lying
wetlands
and
seasonally
wet areas in
climax
Themeda
triandra
grasslands
on heavy
black clay
soils, tends
to disappear
from
degraded
grasslands.
Low
ASPHODELACEAE Trachyandra
erythrorrhiza
Black turf
marshes
Low
17
ASTERACEAE Cineraria
longipes
Vulnerable Grassland,
amongst
rocks and
along
seepage
lines,
exclusively
on basalt
koppies on
south-facing
slopes.
None
MESEMBRYANTHEMACEAE Lithops lesliei Near
Threatened
Primarily in
arid
grasslands,
usually in
rocky
places,
growing
under the
protection
of forbs and
grasses.
Low
ORCHIDACEAE Habenaria
bicolor
Near
Threatened
Well-
drained
grasslands
at around
1600 m in
South
Africa.
Low
Extremely limited suitable habitat remains for any threatened red data
plant species due to the high levels of habitat degradation on and
surrounding the site. The channelled valley bottom wetland is heavily
degraded due to uncontrolled cattle grazing and trampling, invasion of
kikuyu Pennisetum clandestinum* as well as extreme habitat degradation
due to raw sewerage entering system through bulk sewer line. No red
listed plant species were observed within the proposed alignments or
significant population are likely to occur around the site due to high levels
of anthropogenic disturbances from the adjacent informal settlements.
18
4. PRELIMINARY FAUNAL HABITAT ASSESSMENT
No comprehensive faunal surveys were conducted and species lists
provided in the Appendix are of species most likely to occur on the site
using habitat as an indicator of species presence.
The following micro-habitats were identified in the study area during the
field investigation:
4.1 Open Grassland
Figure5. A collage of photographs displaying the current impacts
on the site and surrounding grassland include: A: Transformation
and degradation of grasslands through previous and current agricultural
activities; B: Several informal roads and human pathways bisect the open
grasslands resulting in increased human disturbances; C: A large informal
settlement occurs adjacent to the channelled valley bottom wetland, D:
Remnant patch of low-lying quartzite rocky outcrops occur to the north
and east of circuit line alignments. The frequent burning of the site results
in alteration of vegetation as well as impacting on remaining animal
species especially reptiles and smaller mammal species.
19
The grasslands occurring along the alignment have been impacted on
by:
� Informal settlements occur around the site
� Previous and current agricultural activities (oldlands) have
transformed the majority of grassland habitat on site.
� Extensive overgrazing by cattle has resulted in the dominance of
the dwarf shrub (Stoebe vulgaris/ Seriphium plumosum).
� Sand harvesting and borrow pits.
� Eskom power-lines and servitudes bisect the grasslands.
� Numerous paths and an informal roads transverse the grasslands.
� Extensive littering occurs on the site especially adjacent to the
informal settlement.
� Extensive dumping of solid and organic waste throughout the site.
� Frequent burning of remaining grasslands
� Evidence of hunting (shot gun cartridges) and poaching (wire
snares) as well as hunting with dogs.
� Removal of majority of medicinal plant species (bulbous
geophytes); thatch harvesting, wood harvesting and collecting.
� Introduction of exotic and alien vegetation.
The remaining primary grasslands within the study area represent
important habitat for a variety of grassland dependant Red Data species
and should be considered as a sensitive habitat with high conservation
potential. The majority of the proposed circuit alignments follow informal
roads as well as transformed grasslands with minimal disturbances to
remaining open grasslands. Line Option 1 and 2 bisect larger portions of
the channelled valley bottom wetland. Line Option 3 bisects approximately
150m section of low lying quartzite rocky outcrops.
20
4.2 Wetlands including Channelled Valley bottom and artificially
created dams.
Figure6. The proposed circuit alignments run parallel to and bisect a
channelled valley bottom wetland. The proposed alignment 1 and 2 bisect
large portions of the channelled valley bottom wetland and adjacent
seasonally inundated seepage wetlands. Option 3 is situated outside the
channelled valley and follows exiting access road across the valley bottom
and degraded seepage wetland areas. The proposed pylons as well as
access or maintenance road must be placed outside the temporary wet
zone of the channelled valley bottom wetland and seepage wetlands.
21
Figure7. Recent observations (March 2014) of the channelled
valley bottom wetland. A: The channelled valley bottom has become
severely degraded due to continual pollution of raw or untreated sewerage
which enters into the system from a burst bulk sewer line situated within
the seasonal wet zones. B: Uncontrolled livestock drinking of the polluted
water as well as grazing and trampling within the seepage areas. C: Large
sections of the valley bottom have been invaded by kikuyu (Pennisetum
clandestinum*). D: Extensive illegal dumping activities within the valley
bottom wetland.
The valley bottom and associated riparian zone, of which grassland
vegetation is a major component, has a number of important functions
including:
• enhancing water quality in the river by the interception and
breakdown of pollutants;
• interception and deposition of nutrients and sediments;
• stabilisation of riverbanks and macro-channel floor;
• flood attenuation;
• provision of habitat and migration routes for fauna and flora;
• provision of fuels, building materials and medicines for communities
(if done on a sustainable basis); and
22
• recreational areas (fishing - rod and line not shade or gill nets; bird
watching; picnic areas etc.).
Wetlands are characterized by hydric/hydromorphic soils and slow flowing
water and tall emergent vegetation, and provide habitat for many faunal
species including African Grass Owl. The conservation status of many of
the faunal species that are dependant on wetlands reflects the critical
status of wetland nationally, with many having already been destroyed. In
this study area wetlands, including seasonal dams offer the most suitable
habitats for species such as African Grass Owls; Giant Bullfrogs, Rough-
haired Golden Mole, Marsh Sylph which may possibly occur in the area.
The high levels of human disturbances associated with the informal
settlement along the valley bottom; significantly reduces the likelihood of
any African Grass Owls or Giant Bullfrogs occurring along the alignment or
remaining in the palustrine wetland system.
All remaining wetlands (permanent and seasonal) and their associated
indigenous grassland and sedge dominated vegetation must be considered
as sensitive habitats and of high conservation value. Indigenous
marshland vegetation such as that found adjacent to the proposed
alignment comprises a habitat which is restricted in extent, highly
productive and which contains a high diversity of plants and animals,
many of which are restricted or heavily dependant on such habitats.
Several mammal species including Vlei Rats, Cape Clawless Otter and
Marsh Mongoose may possibly occur along the valley bottom and
artificially created dams. The high levels of human disturbances as well as
hunting with dogs and snares will heavily impact on remaining mammal
species along the valley bottom. Waterbirds, which were formerly
restricted to high rainfall areas with natural wetland habitat, make use of
man-made dams, and surrounding areas, for feeding, roosting and
breeding. Certain amphibian species will utilize the shallow margins of the
dam for breeding purposes including Guttural Toad, Common River Frog,
Common Caco, Bubbling Kassina. Common Platanna will be found in
permanent waterbodies along the alignment. Reptile species such as the
Brown water Snake, Water Monitor are associated with wetland habitats
including permanent dams. Low amphibian diversity is expected due to
the continual deterioration of water quality due to raw sewerage
constantly entering into the system.
23
More comprehensive surveys must be conducted if the alternatives 1 and
2 alignment are considered especially pertaining to the position of towers
bisecting the valley bottom wetlands as well as potential collision of
avifauna (birds). This will include recommendations on the installation of
anti-collision devices along the section of line adjacent to the valley
bottom as well as alignments bisecting the valley bottom.
4.3 Quartzite Ridge
Figure8. The proposed alignment 3 runs adjacent to a quartzite
rocky outcrop or extrusion. The rocky ridge has been severely
degraded due to the high levels of anthropogenic disturbances. The
proposed alignment should be restricted to the degraded and overgrazed
grasslands on the mid slopes in order to prevent further disturbances to
the lower lying more extensive quartzite outcrops. Rocky outcrops provide
critical habitat for numerous rupicolous (living on or amongst rock) faunal
species including smaller mammals and reptiles.
24
The small rocky hill offers favourable habitat for several rupicolous (living
on or amongst rocks) animal species. A wide variety of bird groups utilise
ridges, koppies and hills for feeding, roosting and breeding. These groups
include several Spotted and Water Thick-Knees, Blacksmith and Crowned
Lapwings as well as a Northern Black Korhaan. Ridges provide important
habitats for certain rupicolous mammals such as the eastern rock elephant
shrew. The quartzite rocky outcrops must be considered as a sensitive
habitat with medium-high conservation value in a local scale.
4.4 Exotic trees
Figure8. Large areas surrounding the proposed alignments are heavily
invaded by Saligna Gum (Eucalyptus grandis) as well as Black Wattle
(Acacia mearnsii).
Significant patches of Black Wattle and Eucalyptus trees were observed in
the study area, particularly near human settlements as well as agricultural
lands. Whilst in general exotic vegetation has little value for most faunal
species, in this study area, the lack of other trees means that these
stands may be used by some faunal species such as Common Duiker,
Porcupine as refuge habitat.
25
4.5 Agricultural lands
Figure9. Large monoculture agricultural lands occur adjacent to the
existing 44kV line which the circuit line connects with.
Arable or cultivated land represents a significant feeding area for certain
rodent species such as Highveld Gerbil and Multimammate Mouse through
the tilling opening up the soil surface, land preparation makes many
insects, seeds, bulbs and other food sources are suddenly accessible.
Maize lands are dominated by seed eating birds such as Laughing Dove,
Cape Turtle Dove as well as Helmeted Guineafowls. Rodents construct
burrows in the sandy soils and attract other predators such as the slender
mongoose.
26
5. RESULTS OF THE INITIAL FAUNAL SURVEY OR
HABITAT ASSESSMENT
5.1 MAMMALS
No small mammal trapping was conducted. Fieldwork was augmented
with previous surveys in similar habitats as well as published data. The
area was initially traversed on foot to ascertain the presence of available
refuges. Refuges such as burrows, refuge piles, overgrazed and rank
grasslands were surveyed.
Table2. Mammal species recorded during field survey. Identification
was determined by visual observations, trapping and animal tracks
(footprints and droppings).
COMMON NAME SCIENTIFIC NAME
Scrub Hare Lepus saxtalis
Common Molerat Cryptomys hottentotus
Highveld Gerbil Tatera brantsii
Yellow Mongoose Cynictis penicillata
Slender Mongoose Galerella sanguinea
*House mouse Mus musculus
*House Rat Rattus rattus
*Domestic Dog Canis familiaris
*Feral Cat Felis catus
* introduced species
Threatened species
No sensitive or endangered mammals were recorded within the study area
or are likely to occur along the proposed alignment 1 or substation sites.
The proposed alternatives 1 and 2 run parallel and bisect the channelled
valley bottom which could potentially impact on the remaining (albeit
limited) wetland associated mammals. The majority of larger mammal
species are likely to have been eradicated or have moved away from the
area, as a result of habitat alteration and degradation as well as illegal
hunting and poaching. The sandy soils of the previously ploughed fallow
lands offers habitat for burrowing rodents such as the Highveld Gerbil. All
trees on the site are exotic and mainly invasive (Eucalyptus and Black
27
Wattle) and limited termite mounds were observed (due to previous
agricultural activities). Hunting with dogs was noted during the site visits.
Smaller mammal species are extremely vulnerable to snares and poaching
activities as well as feral cats and dogs. According to the “South African
Red Data Book of Terrestrial Mammals” (Smithers 1986) and Skinner and
Chimimba (2005), the study area falls within the distribution ranges of 12
species which are placed into one of known threatened species
(Endangered, Vulnerable and Rare). Due to the high level of human
activity (squatter camps) within the study area as well as the previous
agricultural activities it is however unlikely that the study area comprises
significant habitat for any species of threatened mammals. Several people
live in informal housing on or surrounding the site. Illegal hunting with
dogs and feral cats will lead to the disappearance of the majority of
mammals in the area. Suitable habitat occurs along the valley bottom for
Vlei Rats and Marsh/Water Mongoose.
5.2 AVIFAUNAL (BIRD) SURVEY
During the site visitation (total of 10 hrs), 32 bird species were recorded.
Species recorded during field survey are common, widespread and typical
of a disturbed grassland environment as well as wetland system. One
hundred and twenty five (125) species have been recorded for the
2605_2840 pentad in which the substation and powerline are situated. No
threatened birds were recorded during the survey or are likely to occur at
the proposed substation sites.
28
Table2: Bird species recorded during brief field survey (10hrs);
introduced species are in bold.
Roberts’
Number
Common name
Scientific Name
71 Cattle Egret Bulbulcus ibis
94 Hadeda Ibis Bostrychia hagedash
127 Blackshouldered Kite Elanus caeruleus
199 Swainson’s Francolin Francolinus swainsonii
200 Common Quail
Coturnix coturnix
203 Helmeted Guineafowl
Numida meleagris
Northern Black Korhaan Afrotis afroides
255 Crowned Lapwing (Plover) Vanellus coronatus
258 Blacksmith Lapwing (Plover) Vanellus armatus
297 Spotted Dikkop Burhinus capensis
352 Redeyed Dove Stretopelia semitorquata
354 Cape Turtle Dove Streptopelia capicola
355 Laughing Dove Streptopelia senegalensis
391A Burchell’s Coucal Centropus burchellii
415 Whiterumped Swift Apus caffer
417 Little Swift Apus melba
424 Speckled Mousebird Colius striatus
451 Hoopoe Upupa epops
452 Redbilled Woodhoopoe Phoeniculus purpureus
464 Blackcollared Barbet Lybius torquatus
473 Crested Barbet Tracchyphonus vailantii
483 Cardinal Woodpecker Dendropicos fuscescens
494 Rufousnaped Lark Mirafra africana
507 Redcapped Lark Calandrella cinerea
518 European Swallow Hirundo rustica
526 Greater Striped Swallow Hirundo cucullata
527 Lesser Striped Swallow Hirundo abyssinica
548 Pied Crow Corvus albus
29
568 Dark-capped (Black-eyed)
Bulbul
Pycnonotus barbatus
577 Olive Thrush Turdus olivaceus
596 Stonechat Saxicola torquata
601 Cape Robin Cossypha caffra
645 Barthroated Apalis Apalis thoracica
664 Fantailed Cisticola Cisticola juncidis
672 Rattling Cisticola Cisticola chiniana
683 Tawnyflanked Prinia Prinia subflava
701 Chinspot Batis Batis molitor
716 Grassveld Pipit Anthus cinnamomeus
727 Cape or Orange-throated
Longclaw
Macronyx capensis
732 Fiscal Shrike Lanius collaris
758 *Indian Myna Acridothermes tristis
787 Whitebellied Sunbird Nectarinia talatala
796 Cape White-Eye Zosterops pallidus
801 *House Sparrow Passer domesticus
814 Masked Weaver Ploceus velatus
815 Lesser Masked Weaver Ploceus intermedius
824 Red Bishop Euplectes orix
860 Pintailed Whydah Vidua macroura
869 Yelloweyed Canary Serinus mozambicus
30
SENSITIVE OR ENDANGERED SPECIES
Table4. List of threatened and near-threatened bird species that occur in
the proposed 2605-2840 pentad and that could occur at or near proposed
site according to Barnes (2000).
Species Conservatio
n status (Barnes
2000)
Reporting
rate SABAP2
%
Habitat
requirements (Barnes
2000; Hockey et al 2005; Harrison et al
1997; personal
observations)
Probability of
Occurrence
Greater
Flamingo Phoenicopterus ruber
Near
threatened
11.1 Endorheic
pans, saltworks, sewerage
works and large
impoundments
Medium-Low
Black-winged
Pratincole Glareola nordmanni
Near
threatened
11.1 Attracted to
agricultural lands which are regularly
ploughed
Medium-High
African Grass-
Owl Tyto capensis
Vulnerable
- Normally
associated with pristine, well
managed grasslands usually in close
proximity of water, but also
in alien vegetation structurally
resembling tall or rank
grassland, and hydrophilic sedges.
Medium-Low
Limited rank hydrophilic grass and sedge vegetation occurs along the
valley bottom. Trampling by cattle as well as high levels of human
disturbances limits the section of the valley bottom for African Grass Owls
as well as Grater Flamingo. The valley bottom wetland habitat on the site
is heavily impacted on by surrounding informal settlement. Limited
suitable habitat occurs on the site and surrounding areas for any of the
31
above-mentioned threatened bird species. The majority of species would
have disappeared during the previous agricultural activities on and
surrounding the site and surrounding areas. The large informal settlement
adjacent to the valley bottom and transformation and degradation of
surrounding grassland areas severely restricts the remaining bird
populations due to habitat destruction as well as increased disturbances
(catapults, hunting etc). The low lying quartzite ridge could potentially
offer suitable foraging and exploratory habitat for the nomadic Black-
winged Pratincole.
5.3 AMPHIBIANS
No actual survey was undertaken due to incorrect time of the year for a
herpetological survey. The majority of species in Mpumalanga Province
are classified as explosive breeders completing their short duration
reproductive cycle in the early summer months between (November-
January). These frog species only emerge after the first heavy summer
rainfalls and are dormant during the cold winter months. Explosive
breeding frogs utilise ephemeral pans or inundated grasslands for their
short duration reproductive cycles.
As the survey was undertaken for 2 days (no nocturnal surveys) during
the late summer months (March-April) only a few species of amphibians
were active. Four frog species were recorded namely Striped Stream Frog
(Strongylopus fasciatus) Common Plattana (Xenopus laevis), Guttural
Toad (Amietophrynus (Bufo) gutturalis) and Common River Frog (Amietia
angolensis). Comprehensive herpetological surveys can only be
undertaken throughout the duration of the wet season (November-March).
It is only during this period that accurate frog lists can be compiled.
32
Figure10. A conglomerate of photographs displaying frog species
likely to occur on the site. A: Common Caco (Cacosternum boettgeri)
breeds in shallow seasonally inundated grassland such as adjacent to the
valley bottom wetland. B: The Guttural Toad (Amietophrynus gutturalis) is
an urban exploiter and breeds in various man made habitats as well as
degraded wetlands. C: Tremelo Sand Frog (Tompoterna cryptotis) will
breed in seasonal roadside pools. D: Bubbling Kassina (Kassina
senegalensis) breed in seasonally inundated habitats. The ongoing
pollution by untreated sewerage entering the valley bottom wetland from
the outfall sewer line is an immediate threat to remaining frog species.
33
Table5. Frog species recorded for locus = 2628AC according to SAFAP.
Family Genus Species Common
name
Red list
category
Atlas
region
endemic
Bufonidae Amietophrynus garmani Olive
Toad
Least
Concern
-
Bufonidae Amietophrynus gutturalis Guttural
Toad
Least
Concern
-
Bufonidae Amietophrynus rangeri Raucous
Toad
Least
Concern
-
Bufonidae Schismaderma carens Red Toad Least
Concern
-
Hyperoliidae Kassina senegalensis Bubbling
Kassina
Least
Concern
-
Pipidae Xenopus laevis Common
Platanna
Least
Concern
-
Pyxicephalidae Amietia angolensis Common
or Angola
River
Frog
Least
Concern
-
Pyxicephalidae Amietia fuscigula Cape
River
Frog
Least
Concern
-
Pyxicephalidae Cacosternum boettgeri Common
Caco
Least
Concern
-
Pyxicephalidae Tomopterna cryptotis Tremelo
Sand
Frog
Least
Concern
-
Pyxicephalidae Tomopterna natalensis Natal
Sand
Frog
Least
Concern
-
34
HABITAT AVAILABLE FOR SENSITIVE OR ENDANGERED SPECIES
Figure11. Giant Bullfrogs (Pyxicephalus adspersus) have been recorded
from sites to the south of Delmas in the Nigel area.
Giant Bullfrog (Pyxicephalus adspersus)
The Giant Bullfrog is currently assigned as a near-threatened species
(IUCN Red List category). Giant Bullfrogs have been recorded from the
adjacent grid squares (Nigel area) during previous surveys as well as
during the South African Frog Atlas Project (SAFAP). Specimens recorded
were of road fatalities, migrating adult males as well as confirmed
breeding localities in the Nigel area. Bullfrog density commonly varies
within certain habitats (open grassland habitat). High densities are often
associated with specific microhabitats or patches (hygrophytic or aquatic
ephemerophytic grass and sedge dominated temporary pans) that can be
identified and randomly sampled. Emphasis must be placed on remaining
natural open grassland habitats (important migratory and foraging areas)
as well as seasonal wetlands (drainage and marshland vegetation)
surrounding the alignment. The channelled valley bottom wetland offers
no suitable breeding habitat for Giant Bullfrogs. Due to extensive habitat
transformation as well as high levels of human disturbances it is highly
unlikely that any Giant Bullfrogs remain in the area.
35
5.4 REPTILES
Reptile lists require intensive surveys conducted for several years.
Reptiles are extremely secretive and difficult to observe during field
surveys. The majority reptile species are sensitive to severe habitat
alteration and fragmentation. Due to human presence in the area coupled
with increased habitat destruction and disturbances around the alternative
sites are all causal factors in the alteration of reptile species occurring on
the site and surrounding areas. The small rocky hill provides favourable
refuges for certain snake and lizard species (rupiculous species). A few
termite mounds Trinervitermes haberlandii were observed along and
around the proposed alignments. Termite mounds offer important refuges
for numerous frog, lizard and snake species. Large number of species of
mammal, birds, reptiles and amphibians feed on the emerging alates
(winged termites). These mass emergences coincide with the first heavy
summer rains and the emergence of the majority of herpetofauna.
Termite mounds also provide nesting site for certain snake, lizards
(varanids) and frogs.
The indiscriminate killing of all snake species as well as the illegal
collecting of certain species for private and the commercial pet industry
reduces reptile populations especially snake populations drastically. The
frequent burning of the site will have a high impact on remaining reptiles.
Fires during the winter months will severely impact on the hibernating
species, which are extremely sluggish. Fires during the early summer
months destroy the emerging reptiles as well as refuge areas increasing
predation risks.
36
Figure12. Reptile species recorded from the quartzite outcrops
adjacent to the alignment 3 included A: The endemic Distant’s Ground
Agama (Agama aculeate distanti. B: Transvaal Gecko (Pachydactylus
affinis) was observed in a moribund termite mound. C: Mole Snake
(Pseudaspsis cana) was observed in the rocky hills to the north of the
alignment. D: Approximately 20 termite mounds including moribund
mounds were observed adjacent to the rocky outcrops increasing in
number towards the valley bottom. These moribund termite mounds offer
suitable habitat for several reptile species including the red listed Striped
Harlequin Snake.
37
Table6. Reptile species recorded from the 2628AC locus according to the
South African Reptile Conservation Assessment (SARCA).
Family Genus Species Subspecies Common
name
Red list
category
(SARCA
2014)
Atlas
region
endemic
Agamidae Agama aculeata distanti Distant's
Ground
Agama
Least Concern Yes
Agamidae Agama atra Southern
Rock Agama
Least Concern
Atractaspididae Aparallactus capensis Black-headed
Centipede-
eater
Least Concern
Atractaspididae Atractaspis bibronii Bibron's
Stiletto Snake
Least Concern
Atractaspididae Homoroselaps dorsalis Striped
Harlequin
Snake
Near
Threatened
Yes
Atractaspididae Homoroselaps lacteus Spotted
Harlequin
Snake
Least Concern Yes
Colubridae Boaedon capensis Brown House
Snake
Least Concern
Colubridae Crotaphopeltis hotamboeia Red-lipped
Snake
Least Concern
Colubridae Dasypeltis scabra Rhombic Egg-
eater
Least Concern
Colubridae Duberria lutrix lutrix South African
Slug-eater
Least Concern Yes
Colubridae Lamprophis aurora Aurora House
Snake
Least Concern Yes
Colubridae Lycodonomorphus inornatus Olive House
Snake
Least Concern Yes
Colubridae Lycodonomorphus rufulus Brown Water
Snake
Least Concern
(SARCA 2014)
Colubridae Lycophidion capense capense Cape Wolf
Snake
Least Concern
Colubridae Prosymna sundevallii Sundevall's
Shovel-snout
Least Concern
Colubridae Psammophis crucifer Cross-marked
Grass Snake
Least Concern
(SARCA 2014)
Colubridae Psammophylax rhombeatus rhombeatus Spotted
Grass Snake
Least Concern
(SARCA 2014)
Cordylidae Cordylus vittifer Common
Girdled Lizard
Least Concern
Cordylidae Pseudocordylus melanotus melanotus Common
Crag Lizard
Least Concern Yes
38
Elapidae Elapsoidea sundevallii media Highveld
Garter Snake
Not listed
Elapidae Hemachatus haemachatus Rinkhals Least Concern
Gekkonidae Lygodactylus capensis capensis Common
Dwarf Gecko
Least Concern
Gekkonidae Pachydactylus affinis Transvaal
Gecko
Least Concern Yes
Gekkonidae Pachydactylus capensis Cape Gecko Least Concern
Gerrhosauridae Gerrhosaurus flavigularis Yellow-
throated
Plated Lizard
Least Concern
Lacertidae Nucras lalandii Delalande's
Sandveld
Lizard
Least Concern Yes
Leptotyphlopidae Leptotyphlops scutifrons conjunctus Eastern
Thread Snake
Not listed
Leptotyphlopidae Leptotyphlops scutifrons scutifrons Peters'
Thread Snake
Not listed
Pelomedusidae Pelomedusa subrufa Marsh
Terrapin
Least Concern
Scincidae Afroablepharus wahlbergii Wahlberg's
Snake-eyed
Skink
Least Concern
Scincidae Trachylepis capensis Cape Skink Least Concern
Scincidae Trachylepis punctatissima Speckled
Rock Skink
Least Concern
Scincidae Trachylepis varia Variable
Skink
Least Concern
Testudinidae Stigmochelys pardalis Leopard
Tortoise
Least Concern
Typhlopidae Afrotyphlops bibronii Bibron's Blind
Snake
Least Concern
Typhlopidae Rhinotyphlops lalandei Delalande's
Beaked Blind
Snake
Least Concern
Viperidae Bitis arietans arietans Puff Adder Least Concern
Viperidae Causus rhombeatus Rhombic
Night Adder
Least Concern
39
HABITAT AVAIALBLE FOR SENSITIVE OR ENDANGERED SPECIES
The Striped Harlequin Snake (Homoroselaps dorsalis), which is
categorised as Near-Threatened in the latest Red Data List has been
recorded from the 2628AC grid square (ReptiMAP/SARCA 2014).
According to the habitat description (moribund/old termite mounds and
scattered loose rock) provided for this species by Broadley (1990) and
Branch (1988); extremely limited suitable habitat exists on the small
rocky hill in the form of moribund termite mounds as well as loosely
embedded rocks for the Striped Harlequin Snake. As a precautionary
measure a suitable qualified herpetologist should closely examine the
proposed tower positions for any loosely embedded rocks or moribund
termite mounds. If the termite mounds have to be destroyed they should
be carefully excavated and any reptile species recovered relocated in
suitable habitat away from the powerline.
40
Figure13. The proposed powerline and substation bisect mainly modified
(old lands) as well as limited natural areas according to the Mpumalanga
Conservation Plan (2014).
41
6. RANKING OF ALTERNATIVES 6.1. PROPOSED DELMAS NORTH SUBSTATION
The two proposed Delmas North Substations are situated in transformed
or secondary grasslands. Alternative 1 is situated adjacent to the Botleng
Cemetery. The second alternative site is situated within the McCains
property approximately 800m to the west of alternative 1. Extensive
dumping from the surrounding settlements occurs on and around the sites
as well as the frequent burning of the vegetation. The vegetation is
dominated by pioneer weedy plant species. From a faunal and vegetation
point the alternative substation site 1 is the slightly preferred option
as the alternative 2 site is situated adjacent to a degraded seepage
wetland. Both sites are however situated in heavily degraded or
transformed grassland habitats with low sensitivity and low
conservation potential.
6.2 LOOP-IN-LINE ALTERNATIVE ALIGNMNETS
Alternative 3 is the preferred alternative from a faunal and vegetation
perspective as the majority of the alignment occurs within transformed
grasslands such as agricultural lands, degraded grasslands and road
reserves. The alternative 3b is slightly preferred over 3a as it follows
completely transformed informal access roads. Alternative 1 will most
likely result in a low impact on remaining faunal species and limited
habitat destruction of mainly transformed or secondary grassland
vegetation within a local Delmas scale. It also only bisects a short section
of the valley bottom wetland adjacent to an existing access road.
Alternative 1 and 2 run parallel with the channelled valley bottom
wetland as well as bisecting larger sections of the valley-bottom wetland.
The proposed alignment could potentially result in further impacts on the
sensitive wetland system such as driving of vehicles in seasonal and
temporary wet zones of the wetland; compaction of the hydromorphic
soils, destruction of the hygrophytic vegetation as well as increased
disturbances to the associated fauna. Alternative 1 and 2 will have a
medium to low impact on remaining faunal species. More comprehensive
wetland as well as avifaunal surveys should be undertaken along the
valley bottom wetland if alternatives 1 or 2 are selected as the preferred
options.
42
Figure14. Preliminary sensitivity map for the Delmas substation and
circuit line
43
7. GENERIC DESCRIPTION OF POTENTIAL IMPACTS
OF POWER LINES ON ASSOCIATED FAUNA
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 disturbance and habitat destruction during construction and
maintenance activities.
7.1 Habitat destruction and disturbance
During the construction phase and maintenance of powerlines, some
habitat destruction and alteration inevitably takes place. This happens
with the construction of access roads, and the clearing of servitudes.
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 fauna breeding, foraging and roosting in or in close proximity of the
servitude, both through modification of habitat and disturbance caused by
human activity. The proposed impact will be of medium-low; short-long
term impact on remaining (albeit) limited faunal species.
Mitigation and Recommendations
The following general recommendations are made to minimise the impacts
of proposed powerline construction on the immediate environment and
remaining fauna:
� Close site supervision must be maintained during construction.
� During the CONSTRUCTION phase workers must be limited to
areas under construction and access to the undeveloped areas,
especially the surrounding open areas must be strictly regulated
(“no-go” areas during construction activities).
� Provision of adequate toilet facilities must be implemented to
prevent the possible contamination of ground (borehole) water in
the area. Mobile toilets must be provided in order to minimise
unauthorised traffic of construction workers outside of the
designated areas.
44
� All temporary stockpile areas including litter and dumped material
and rubble must be removed on completion of construction. All
alien invasive plant should be removed from the site to prevent
further invasion.
� No servitudes should be constructed within any wetland habitat as
well as a 20m grassland buffer from the outer edge of the
temporary wet zone.
� Access to the powerline servitude must be restricted. Access to the
powerline servitude should ideally be fenced off and gated along the
main access roads. No quad-bikes, motorcycles or off road vehicles
and illegal hunting should be permitted along the valley bottom
wetland.
� Firearms or any other hunting weapons must be prohibited on site.
� Contract employees must be educated about the value of wild
animals and the importance of their conservation.
� Educational programmes for the contractor’s staff must be
implemented to ensure that project workers are alerted to the
possibility of snakes being found during vegetation clearance. The
construction team must be briefed about the management of
snakes in such instances. In particular, construction workers are to
go through ongoing refresher courses to ensure that threatened
snakes, such as Striped Harlequin Snakes, are not killed or
persecuted when found.
� Severe contractual fines must be imposed and immediate dismissal
on any contract employee who is found attempting to snare or
otherwise harm wild animals.
� No animals should be intentionally killed or destroyed and poaching
and hunting should not be permitted on the site.
� No specific recommendations are made for the protection of
burrowing red data mammals. Consideration could be given to
rescuing the animals where there burrows are found in advance of
construction. This is not recommended as a general prescription
since the chances of digging out live Aardwolf or Antbear are small.
Aardwolf are likely to vacate their burrows in the face of the
advancing construction. There is also a risk associated with
capturing animals dug out of burrows, and holding them in
captivity. If a section of many active burrows is found then
mitigation should be considered (minor deviation to the powerline
alignment or rescue operation for the animals).
45
7.2 VEGETATION/FLORA
Protected or endangered species may possibly occur along the line route.
Special care should be taken not to damage or remove any such species
unless absolutely necessary. Permits for removal must be obtained from
Provincial Nature Conservation should such species be affected. All plants
not interfering with the operation of the line shall be left undisturbed.
Collection of firewood and traditional medicinal plants is strictly prohibited.
No area should be cleared of trees, bushes and other vegetation for the
purpose of a camping site. The proposed alignments will have a low
impact if the following mitigatory measures are implemented.
Management objective
• Minimal disturbance to vegetation where such vegetation does not
interfere with construction and operation of the line. As the
alignments are situated within a grassland vegetation unit minimal
vegetation clearance is necessary.
• No unnecessary destruction to surrounding vegetation
• Prevention of litigation concerning removal of vegetation
Measurable targets
• Adequate protection of any endangered or threatened plant or tree
species. No endangered plant species were observed during brief field
assessment.
• No litigation due to removal of vegetation without the necessary
permits
Mitigation and recommendation
Remaining indigenous bulbous geophytes and Aloes should be retained or
replanted wherever possible. Where herbicides are used to clear
vegetation, specimen-specific chemicals should be applied to individual
plants only. General spraying should be prohibited.
All alien vegetation should be eradicated over a five-year period. Invasive
species (Acacia mearnsii, A. dealbata, Eucalyptus) should be given the
highest priority. No dumping of any materials in undeveloped open areas
and neighbouring properties. Activities in the surrounding open
undeveloped areas (especially valley bottom and rocky hill) must be
strictly regulated and managed.
46
The construction of the proposed powerline could result in limited
opening-up of the vegetal cover during the construction phase. The
opening up of existing vegetated areas, thereby creating corridors along
which animals can move, may result in increased predation levels on small
mammals, reptiles, amphibians, arachnids and scorpions along these
corridors. The limitation of the disturbance of vegetation cover as well as
rocky outcrops, logs, stumps, termite mounds within sensitive areas will
ameliorate this impact. Impact will be short-long term depending on the
amount of vegetation to be cleared. Excessive habitat destruction during
construction could reduce the amount of habitat available. This impact is
anticipated to be localised, of a long-term nature and of low significance,
provided that appropriate mitigation measures are implemented (e.g. the
limitation of vegetation clearance within sensitive areas).
Prior to construction and vegetation clearance a suitably qualified
Zoologist/Botanist or Environmental Control Officer (ECO) should closely
examine the proposed construction areas (tower supports) for the
presence of any animal burrows (including spiders and scorpions), rocky
outcrops, logs, stumps and other debris and relocate any affected animals
to appropriate habitat away from the servitude or tower.
7.3 REVEGETATION
Where necessary a suitable mixture of grass seed shall be used to re-seed
damaged areas. Badly damaged areas shall be fenced in to enhance
rehabilitation. Areas to be rehabilitated must be planted with a mixture of
endemic pioneer grass species endemic to the area, as soon as the new
growing season starts. To get the best results in a specific area, it is a
good idea to consult with a vegetation specialist or the local extension
officer of the Dept of Agriculture. Seed distributors can also give valuable
advice as to the mixtures and amount of seed necessary to seed a certain
area. Re-seeding, as well as fencing in of badly damaged areas, will
always be at the discretion of the Environmental Control Officer, unless
specifically requested by a Landowner.
Management objective
• Minimise damage to topsoil and environment at tower positions
• Successful rehabilitation of all damaged areas
• Prevention of erosion
47
Measurable targets
• No loss of topsoil due to construction activities
• All disturbed areas successfully rehabilitated within three months of
completion of the contract
• No visible erosion scars three months after completion of the contract
A mixture of seed can be used provided the mixture is carefully selected
to ensure the following:
a) Annual and perennial plants are chosen.
b) Pioneer species are included.
c) All the plants shall not be edible.
d) Species chosen will grow in the area without many problems.
e) Root systems must have a binding effect on the soil.
f) The final product should not cause an ecological imbalance in the area.
CONSTRUCTION PHASE
• Disturbed areas of natural vegetation as well as cut and fills must be
rehabilitated immediately to prevent soil erosion.
• Re-seeding shall be done on disturbed areas as directed by the
Environmental Control Officer.
7.4 Surrounding Farming Activities
Domestic Livestock
Construction activities must be planned carefully so as not to interfere
with the calving and lambing season for most animal species. The
Contractor’s workforce will have to be very careful not to disturb the
animals as this may lead to fatalities which will give rise to claims from
the Landowners. Interference with any wildlife without the applicable
permits shall not be allowed. The Contractor shall under no circumstances
interfere with livestock without the Landowner being present. This
includes the moving of livestock where they interfere with construction
activities. Should the Contractors workforce obtain any livestock for eating
purposes, they must be in possession of a written note from the
Landowner. Speed limits must be restricted especially on farm roads
(30km/hr) preventing unnecessary road fatalities of surrounding livestock.
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Management objective
• Minimise disruption of surrounding farming activities
• Minimise disturbance of fauna
• Minimise interruption of breeding patterns of fauna
Measurable targets
• No hunting and poaching or intentional killing of animals (including
snakes, scorpions, spiders)
• No stock losses where construction is underway
• No complaints from Landowners or Nature Conservation
• No litigation concerning stock losses and animal deaths
7.5 ACCESS ROADS
Planning of access routes must be done in conjunction between the
Contractor, Eskom and the Landowner. All access to private farmland
must be negotiated in advance with land-owners. All agreements reached
shall be documented in writing and no verbal agreements should be
made. The condition of existing access / private roads to be used shall be
documented with photographs.
The Contractor shall properly mark all access roads. Markers shall show
the direction of travel as well as tower numbers to which the road leads.
Roads not to be used shall be marked with a "NO ENTRY" sign.
Unnecessary traversing of agricultural and natural open land is
discouraged. Where required, speed limits shall be indicated on the roads
(30km). All speed limits shall be strictly adhered to at all time.
Vehicle access to the powerline servitude must as far as possible be
limited to existing roads. If a new access roads need to be constructed it
should follow cleared areas such as cattle pathways. The following
mitigation should also be undertaken:
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7.6 VEGETATION CLEARANCE
Management objective
• Minimise damage to surrounding vegetation
• Minimise damage to topsoil
• Successful rehabilitation of barren areas
Measurable targets
• No damage to vegetation outside the road servitude
• No loss of topsoil
• No visible erosion three months after completion of the contract
• All disturbed areas successfully rehabilitated three months after
completion of the contract
The object of vegetation clearing is to trim, cut or clear the minimum
number of trees and vegetation necessary for the safe mechanical
construction and electrical operation of the transmission line. Only an 8m
strip may be cleared flush with the ground to allow vehicular passage
during construction. No scalping shall be allowed on any part of the
servitude road unless absolutely necessary. The removal of all
economically valuable trees or vegetation shall be negotiated with the
Landowner before such vegetation is removed. No indigenous tree species
occur within the proposed substation sites or alignments. Only trees are
alien invasive species which must be removed.
Vegetation clearing on tower sites must be kept to a minimum. Big trees
with large root systems shall be cut manually and removed, as the use of
a bulldozer will cause major damage to the soil when the root systems are
removed. Stumps shall be treated with herbicide. Smaller vegetation can
be flattened with a machine, but the blade should be kept above ground
level to prevent scalping. Any vegetation cleared on a tower site shall be
removed or flattened and not be pushed to form an embankment around
the tower.
No vegetation clearing in the form of de-stumping, scalping or uprooting
shall be allowed on river- and stream banks (riparian zone). Vegetation
shall only be cut to allow for the passage of the pilot-cables and
headboard. Trees and vegetation not interfering with the statutory
clearance to the conductors can be left under the line. Dense vegetation
under the line which could cause a fire hazard, particularly in the middle
third of the span in the vicinity of the lowest point of the conductors, will
50
be considered as a separate case. With permission of the landowner, the
total servitude under the line and up to 5m outside the outer phases can
be cleared.
Disturbed areas of natural vegetation as well as cut and fills must be
rehabilitated immediately to prevent soil erosion.
The use of herbicides shall only be allowed after a proper investigation
into the necessity, the type to be used, the long-term effects and the
effectiveness of the agent. Eskom's approval for the use of herbicides is
mandatory. Application shall be under the direct supervision of a qualified
technician. All surplus herbicide shall be disposed of in accordance with
the supplier’s specifications.
Upon completion of the stringing operations and before handover, the
servitude must be inspected and all vegetation interfering with the safe
operation of the line shall be removed / cut down. All alien vegetation in
the total servitude and densifiers creating a fire hazard shall be cleared
and treated with herbicides.
It is recommended that a contractor for vegetation clearing should comply
with the following parameters:
• the contractor must have the necessary knowledge to be able to
identify protected species as well as species not interfering with
the operation of the line due to their height and growth rate.
• the contractor must also be able to identify declared weeds and
alien species that can be totally eradicated.
• the contractor must be in possession of a valid herbicide
applicators licence.
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7.7 Fire Prevention
The frequent burning of the vegetation will have a high impact on
remaining reptile species. Fires during the winter months will severely
impact on the hibernating species, which are extremely sluggish. Fires
during the early summer months destroy the emerging reptiles as well as
refuge areas increasing predation risks.
Management objective
• Minimise risk of veld fires
• Minimise damage to grazing
• Prevent runaway fires
Measurable targets
• No veld fires started by the Contractor’s work force
• No claims from Landowners for damages due to veld fires
• No litigation
Mitigation and recommendations
No open fires shall be allowed on site under any circumstance. The
Contractor shall have fire-fighting equipment available on all vehicles
working on site, especially during the winter months.
7.7 Threatened animals
At a local Delmas North scale the study site and surrounding areas
comprises little or no suitable habitat for any threatened animal species.
Mitigation and recommendations
As a precautionary mitigation measure; a suitably qualified herpetologist
should examine all tower positions and moribund termite mounds for any
Striped Harlequin Snakes; prior to the commencement of construction
activities. In the event that any of the above-mentioned species are
discovered during construction activities the relevant conservation
authorities should be informed and activities surrounding the site
suspended until further investigations have been conducted.
52
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