Contents
of April 2004
EDITORIAL
The
multidisciplinary nature of environmental issues
UPFRONT
News
IDENTIFYING INVADERS
Kahili Ginger Lily and Balloon
Vine
BOOK REVIEWS
South African
Wildflowers/Indigenous Shrubs
TREES OF THE ISSUE
Nigel Butler’s choice of trees
for golf courses
FEATURES
A shared solution for waste disposal
The air that we breathe
Closure and redevelopment of an
industrial site
Exhibiting the unique flora of the Cape
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EDITORIAL
The multidisciplinary
nature of environmental issues
At an event
to celebrate the formation of a partnership between industry, government and academia to
establish a Centre for Sustainability in Mining and Industry at the Wits School of Mining
Engineering, May Hermanus, chief inspector of mines for the Department of Minerals and
Energy, made the comment that the mining industry had fallen into disrepute and had to
obtain a social licence to operate. She spoke not only about the local and global value of
such a Centre for Sustainability but also of its necessary multi-disciplinary nature,
commenting that a particularly exciting aspect of the work towards sustainability was that
it involved many disciplines: the natural and social sciences, engineering, medicine,
economics and ethics, to mention but a few.
The proposed
Centre aims to provide education and training in the field of Safety, Health, Environment
and Community Studies (SHEC) and the provision of short courses will involve academics and
practitioners from across a variety of disciplines.
Urban Green
File looks at environmental issues, including social issues, across a number of
disciplines and this edition truly reflects the multi-disciplinary nature of the journal.
It covers a number of serious urban concerns, including air quality, which is a topic that
we have not tackled in much detail before and which relates to the health of urban
communities. Leigh Darroll has elicited thought-provoking comment on the draft Air Quality
Management Bill, the content of which is currently in the throes of being reworked, from
the National Association for Clean Air and groundWork, a non-profit environmental justice
service and development organisation (page 20).
Environmental
consultant Ritchie Morris delivered a paper at the recent International Association for
Impact Assessment (SA) conference on a brownfield site in Cape Town and he has edited this
into an article (page 24) which emphasises the need to view brownfield sites according to
their future potential, saying that closure of an industrial operation should not be seen
as the end of a site’s use but rather as an opportunity for new initiatives. The
observation made by Professor Paul Ehrlich, in his keynote address to the Conference on
the Conservation of South Africa’s Biodiversity held in Cape Town in 1988, warrants
repeating to bring the point made by Morris into clear focus: “Our first priority in
this uniquely biodiverse portion of the planet should be to ensure that all developments
are located on already disturbed sites – all pristine areas should be considered
sacrosanct”.
The
Overstrand Municipality won the award for the cleanest town in the Western Cape last year
and the report by Leigh Darroll on the integrated waste initiative in the southern Cape
(page 32) shows that the award was well deserved. It is interesting to note the reasons
given for the choice of a so called ‘greenfield’ site for the Karwyderskraal
regional landfill and to note the subsequent care taken to respect both the physical and
visual aspects of the surrounding environment. From the prestigious Arabella Country
Estate across the Bot River, the landfill site looks like farmland.
In reference
to biodiversity, Cape Town’s Unicity building has established a series of open air
courtyards on the new sixth floor of the podium block, which function not only to provide
recreation space and fresh air for the employees but as “mini botanical gardens”
in the words of botanist and garden designer Marijke Honig (page 28). The diverse plant
palette varies from courtyard to courtyard, featuring plants related to different biomes
in the Cape – displaying the unique biodiversity of this corner of the planet. Drip
irrigation has been used to ensure the application of the least possible amount of water
to meet the plant’s requirements. Water-wise landscaping and the use of locally
indigenous plants are key thrusts of our journal.
The themes
of clean air, site remediation, integrated waste management and water conservation are key
issues in the urban environment and core focus areas of the journal – they relate to
all the disciplines involved in urban planning and development. - Carol Knoll
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UPFRONT
Walter Sisulu National Botanical Garden
The
Witwatersrand National Botanical Garden in Witpoortjie, Gauteng, has been renamed the
Walter Sisulu National Botanical Garden as part of the 10 Years of Democracy celebration
this year. The garden, which was founded in 1982, is almost 300ha in size and, with over
30ha under intensive cultivation using exclusively South African plants, is said to be the
fastest growing of the eight botanical gardens belonging to the National Botanical
Institute. Sharon Turner has been the curator of the garden since 2000 and is responsible
for many of the new developments which have served to enrich the garden. She took over
from Peter Chaplin, the first curator of the garden, which was initially established
through revenue raised by the SA Botanical Society in the person of Claire Robbertse, who
raised considerable funding from the private sector. The Botanical Society continues to
lend its fund raising skills to the garden to supplement government funding.
The
cultivated area includes a cycad garden, a fern and forest trail, the new succulent garden
(see UGF Sep/Oct issue 2002) designed and implemented by specialist horticulturist Andrew
Hankey and his dedicated staff, a water-wise demonstration garden, designed by consultant
garden designer Lynton Johnson (see UGF Mar/Apr 1999 issue), the geological garden and the
recently established medicinal plant garden, the structure of which was also designed by
Johnson. The Sasol Dam and wetland area with its secluded bird hide is popular with
birders and, of course, the breeding pair of Black Eagles who nest alongside the
Witpoortjie Waterfall, the centre-piece of the garden, is legend.
The larger
portion of the garden, which runs along the Roodekrans Ridge is maintained as a nature
reserve. There are a number of walks and trails to be done in the cultivated and natural
parts of the garden and the geological trail scales the natural area adjacent to the cliff
face of the waterfall, explaining the exposed rock formations through a series of
information plaques.
The new
restaurant facility should be open by April this year, while a renova¬ted area for the
commercial nursery ‘Random Harvest at the Garden’ is scheduled to re-open a
couple of months later. Events at the garden include the renowned picnic concerts, craft
markets, art in the garden, environmental courses, special children’s events –
and workshops for teachers and learners which are held at the Nestlé Environmental
Education Centre in the garden.
The Minister
of Environmental Affairs and Tourism, Valli Moosa, officially renamed the garden in
mid-March at a colourful event hosted in a large marquee with a backdrop of the
magnificent Witpoortjie Falls. It was attended by numerous dignitaries, including the two
local mayors, and scholars. Moosa emphasised the importance of maintaining SA’s
natural heritage through the diversity of plants evident in the National Botanical Gardens
of the country, saying that it was through the wonderful representation of the
biodiversity of the highveld in the Wits garden that the life of Walter Sisulu and his
long commitment to the struggle for freedom could be celebrated: “A garden that
celebrates the humble beauty of our natural heritage, a heritage that you helped us to
reclaim.”
For more information about the Walter Sisulu NBG. Tel:(011) 958 1750. Email:
info@sisulugarden.co.za Website: www.nbi.ac.za
Wildflower Walk
at Chrissiesmeer
The historic
little town of Chrissiesmeer near Ermelo in Mpumalanga is renowned for the freshwater
lakes, pans, wetlands and the extensive grasslands that surround it. Every year in January
the community-organised Matotoland Ecotourism Association arranges guided Wildflower Walks
into the fields of farmers who open their properties for the occasion. Care is taken to
mark various wildflower species with identification stakes, providing information on the
plant’s demarcating characteristics and other features such as ecological
relationships and medicinal uses.
Individuals
in the community are determined to start keeping a photographic record of the herbaceous
flowering species found on the farms and common land in the vicinity. Community interest
in the flowers and interest from as far afield as Secunda and Gauteng was gratifying to
see, with a group of more than 60 wildflower spotters taking part in the thoroughly
enjoyable and edifying event this year.
Chrissiesmeer,
with its freshwater pans and wetlands, is already renowned for its Frogging Weekends held
every year in November. Matotoland means ‘land of the frogs’. Experts are on
hand to identify the calls of the frogs and point out the physical differences between
species. The attendance has been so good that two weekends have now been set aside for the
event.
Other
ecotourism related activities include Butterfly Weekends, again with experts on hand;
guided bird watching, particularly to see the 78 different species of waterfowl including
Lake Chrissie’s flamingoes, or self-guided tours with bird lists and route maps
provided; and Stargazing evenings in winter at which professional astronomers with
powerful telescopes preside.
Contact Ané Steinberg. Cell: 082 804 1771. Hester Bezuidenhout 073 194 6801
Power down, power
up competition
Young people
at opposite ends of the globe have joined forces to envisage a more positive future in the
aftermath of a fictitious natural disaster. The Welsh Development Agency’s
Environmental Goods and Services Programme devised the pioneering ‘Power Down, Power
Up’ competition and sixth-formers in Cape Town and Cardiff, UK, working with
industrialists and environmental advisors, were asked to imagine the most effective ways
of coping with a permanent international power cut, caused by earthquakes resulting from a
devastating shift in the earth’s geological structure. In addition to a loss of
electricity, the wide-reaching consequences of this would also include an indefinite
global ban on oil and gas extraction for safety reasons.
Their ideas
included immediate action to generate emergency power, safeguard water treatment and
sanitation and ensure effective waste management and pollution control, among other
priorities. Their entries also had to consider the long-term effects up to a century
later, suggesting how schools, industry and transport would function, using alternative
power sources and reducing energy consumption.
Film of both
winning submissions from the Welsh and South African teams will form part of a unique
CD-rom. It is planned that the CD will be distributed further afield to other schools
throughout Wales and South Africa as an innovative teaching aid for studying sustainable
development.
Contact: Jayne Dodgson. Tel: 01352 706227/217 E-mail: jaynedodgson@tiscali.co.uk Website
at www.wda.co.uk
First degree
course in green forensics
The
world’s first degree course in green forensics being presented at the University of
Wales, Bangor, is a proa-ctive move to ensure that the United Kingdom has the skills to
cope with the anticipated changes in environmental legislation. The new degree reflects
the recognition at a national level that the UK’s wealth and security will continue
to depend on the sea in this new millennium. Oil and gas extraction, maritime trade,
aquaculture and fisheries, strategic defence, renewable energy generation and waste
disposal are all important activities underpinned by ocean science.
Increasing
emphasis on these and other environmental issues is leading to growing opportunities for
graduates trained in ocean science to work either at local level, such as on marine and
coastal environmental impact assessment, or on a global scale, to increase marine food
reserves or to determine the role of the oceans in climate change.
The degree
will fill an urgent and growing need for multidisciplinary graduates with the ability to
play the biological, physical or chemical detective to explain the cause or source of
changes to any given ecosystem.
Current
European law means that the polluter pays an often paltry fine for pollution incidents.
All the signs are that European legislation is set to converge with current US practices
where the polluter pays the hefty clean-up costs of any incidents. Changes to European
legislation will require personnel with credible and established expertise in
‘traceability’ - to ascertain who or what caused the pollution and when. It is
also believed that the legal framework in Europe will probably move towards the
“polluter remediates” principle taken in the US. In this situation it is vital
to establish the source of the pollution to determine who is responsible for its
remediation, whether a previous owner of a piece of contaminated land or an adjacent piece
of land. The need to establish original cause of any form of pollution calls for a greater
number and level of environmental forensic experts to deal with such cases.
The forensic
side requires a broad multidisciplinary tool kit. The skills are the same whether the
situation involves the classic industrial pollution and clean-up of ‘brown’
industrial land, establishing the cause of a decline in fisheries stock or whether the
cause is over-fishing, the effects of agricultural ‘run off’ or the introduction
of an alien biological organism, extending to tracing the likely source of a river or
estuarine pollution incident.
The range of
expertise available in the School of Ocean Sciences at the University of Wales is
unrivalled in the UK and the school is one of the few institutions globally that has the
expertise and resources to offer this type of degree.
Website: www.sos.bangor.ac.uk
Property
development company creates wetland habitats on brownfield sites
Tilfen Land
is a fast-growing, property development company with site holdings in the Thamesmead area
of south-east London in the UK. The company is expert in the remediation of brownfield
sites. It aims to break boundaries in design and regeneration to create sustainable
developments that enhance the environment.
Commending
the company for its far-sighted approach in creating a wetland on a previously
contaminated urban site in Thamesmead, the UK’s Living Wetlands Award panel recently
praised Tilfen Land for “going well beyond what was required”. The Living
Wetlands Award scheme was launched in 2003 by the Royal Society for the Protection of
Birds and the Chartered Institute of Water and Environmental Management.
The Tripcock
Wetlands project provides a variety of important habitats for species including the
threatened water vole. Vole populations in the UK are disappearing rapidly because of land
development and the predatory American mink.
In September
2002, 100 voles were released into Tripcock Wetlands. The voles were tagged with
microchips and results indicate that the birds are thriving. The next release is planned
for spring 2004 and the birds will be monitored at regular intervals.
New
watercourses installed by Tilfen Land in Thamesmead are proving a valuable education
resource and Greenwich University students are using the development for site visits and
research projects. Acting as ecological corridors, the watercourses are also an invaluable
public amenity. The design, construction and management of these watercourses has helped
Tilfen’s engineering team gain an appreciation of how development and ecology can be
integrated.
The company
has radically altered the design and construction of Thamesmead’s original lake and
canal network to provide surface water drainage for the new Gallions Reach Urban Village.
The design uses a rock-filled ‘geoweb’ - a semi-rigid material that spreads
across the base of the canal - instead of the traditional concrete. Extensive planted
shallow areas were incorporated into the design and allowed to colonise naturally.
Tilfen Land
has recently joined the Association for Commuter Transport that helps organisations reduce
the impacts of increased commuter and visitor car use around key developments.
The company
has also signed the Mayor of London, Ken Livingstone’s, Green Procurement Code - a
groundbreaking initiative that strives to increase market demand for products made from
recycled materials. Tilfen’s sustainability manager, Mark Philpotts, describes the
Green Procurement Code as playing a crucial role in helping to reduce the waste generated
by London, adding that Tilfen Land is well placed to use recycled materials in its new
developments.
Website: www.tilfenland.co.uk
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IDENTIFYING INVADERS
Kahili Ginger Lily and Balloon Vine
UGF’s
regular column to help with the identification of invasive alien species and their
control.
Hedychium
gardnerianum
Commonly
called the Kahili Ginger Lily, this plant, originally imported into South Africa from the
Himalayas as a garden ornamental, is a declared Category 1 invader. According to the weeds
legislation (regulation 15), Category 1 plants may not occur on any land surface (except
in biological control reserves) and the land user is obliged to remove any Category 1
plants. The plant appears to be a serious problem in Hilton and Pietermaritzburg and other
areas of KZN, where it is spreading across disturbed areas and invading pavements in the
towns, extensively. It is a spectacularly attractive flowering plant and gardeners (and
Parks Dept officials) may well be loth to take it out for this reason. The above
photographs were taken in the KwaZulu-Natal National Botanical Garden in
Pietermaritzburg!! There is an extensive clean-out happening in the garden (which is
largely indigenous) and presumably this plant will be removed in the process.
The plant
grows about 2m in height and has broad leaves and yellow flowers with long red stamens in
large spikes, blooming from January to March. According to Lesley Henderson’s book:
Alien weeds and Invasive Plants, the plant invades forests, plantations, riverbanks and
moist shaded sites and has the invasive status of a transformer – which means that it
can dominate or replace vegetation layers in a natural or semi-natural ecosystem, thereby
altering the structure of the ecosystem and its integrity and functioning. The most
serious environmental weeds are in this group labelled transformers.
Cardiospermum
grandiflorum
Commonly called the Balloon Vine, this is another Category 1 weed which was
also brought into the country as a garden ornamental and originates in tropical America.
The photograph was also taken in the Pietermaritzburg Botanical Garden where the climber
had draped itself over a grouping of indigenous plants. There is a lot of work to be done
in removing invasive species from the garden, which is otherwise well worth the visit
mainly because of its fabulous large trees both indigenous and exotic. It is a little
ironical that on the Botanical Garden property is a private indigenous nursery run by
Andrew James which is distributing a very useful little booklet published by the National
Department of Agriculture called Alien Plants – a Threat to Natural Fauna and Flora
– KwaZulu-Natal Coastal Belt. In the booklet, the Balloon Vine is featured as a
common invader in the area with a note saying that it can grow to enormous lengths and is
capable of smothering a tree of up to 10m tall. In Henderson’s book, the distribution
map shows the Balloon Vine as problematic in the ’Maritzburg area.
The stems of
this woody climber are covered with bristly hairs while the flowers are small and fragrant
and the plant blooms sporadically throughout the year. Its most distinctive feature is its
membranous balloon-like seed capsules. It invades forest margins, watercourses and urban
open space in subtropical regions and its invasive status is the same as the Ginger Lily,
that of a transformer of natural ecosystems.
Contact the
Directorate Agricultural Resource Conservation (responsible for compiling: ‘Alien
Plants: KwaZulu-Natal Coastal Belt’) for copies of the booklet: PO Box 345
Pietermaritzburg 3200.
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BOOK REVIEWS
South African Wildflowers/Indigenous
Shrubs
Author: John Manning
Photographs: John Manning and Colin Paterson-Jones
Publisher: Briza Publications
In his
introduction John Manning, who is a research botanist at the NBI in Cape Town, describes
his objective with this photographic guide to be the provision of a single volume to cover
the country – one that illustrates nearly 900 of the most common and conspicuous
wildflowers in South Africa as a whole. SA has a rich flora of around 19 000 different
species of flowering plants and those depicted in this guide are most likely to attract
the attention of the average traveller to areas where wildflowers are most likely to be
seen: the entire Drakensberg escarpment, the eastern seaboard, the Western Cape and
Namaqualand. Within these areas he has identified three main wildflower regions that
coincide in broad terms with vegetation types: Grassland and Savannah, Fynbos, and
Namaqualand.
For a
beginner wildflower spotter, it would be impractical to buy all the flower guides covering
the country and this alternative of a single guide has been well thought-out and is simple
to use. Unlike other wildflower guides that are colour coded, it has a “quick
guide” in the form of a table structured so as to narrow down options by finding the
correct combination of floral features. This will provide the user with the relevant pages
on which the flower is likely to be found. The plant can then be matched to the
photographic illustrations and simple descriptions provided. Generally, the splendid
photographs are extremely clear and the colours are accurate. The photographs are larger
than in most other field guides.
One of the
most useful aspects, which is not nearly as detailed in other flower guides, is the
depiction of flowering time by means of a bar adjacent to the picture of the flower, which
has the main flowering months highlighted in a darker shading and the months in which
sporadic flowering can be expected given in a lighter shading.
The only
negative is that the distribution maps for each species are too small to be read with any
accuracy and will be difficult to use. They do, however, give a general idea of the
locality of the species.
Easy guide to
indigenous shrubs
Author and photographer:
Pitta Joffe
Publisher:
Briza Publications
This is a
new addition to the Briza Gardening series and Pitta Joffe has described a good selection
of indigenous shrubs that are, on the whole, easy to obtain and to look after. The
photographs are large and clear and illustrate the mature plant, with close-ups of flowers
and sometimes foliage and fruit where relevant. By definition shrubs are ‘bushy’
from ground level – they tend to start branching low down. They can be used for
screening purposes, to block unsightly views and to protect against strong winds. They can
be used as hedges or understorey planting in groupings of trees. Many attract wildlife.
The size of
the fully grown plant is given and the colour of the flower is depicted in a symbol in the
outside bottom corner of the page, along with the months in which it flowers. The
pictograms provide a great deal of easy-to-access information in the form of shape, growth
requirements and other characteristics, such as whether the shrub is deciduous or
evergreen and whether it is wind or drought resistant.
The book has
introductory sections on safe ways of dealing with pests, conserving healthy soil and soil
organisms and utilising mulch. The latter prevents soil erosion, keeps the soil surface
soft and water permeable, acts as a protective blanket reducing evaporation and helps to
aerate soil, encourage the activities of earthworms carrying organic material into the
soil and to some extent to suppress weed growth.
The book
suggests plants that will bring bird and insect life into the landscape and an
introductory section describes certain butterfly host plants and nectar plants that will
encourage specific sunbirds. The kind of wildlife that will be attracted to each species
is described in detail under that particular species.
Contact Briza Publications. Email: info@briza.co.za Website: www.briza.co.za
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TREES OF THE ISSUE
Choice of trees for golf courses
Affecting
playability, aesthetics, maintenance and creation of wildlife habitat
Nigel
Butler, senior course manager at Randpark Club in Randburg, Gauteng, has made the choice
of four indigenous trees, which he has had experience with on the two courses that he
manages.
He explains
not only why these particular trees are appropriate in the golf course situation, but
elaborates on the different roles that trees in general play on a golf course and problems
that are experienced by greenkeepers.
Nigel has
been at Randpark for eighteen years and he expresses the fact that he has always had the
desire to plant more indigenous on a course which has been dominated – particularly
when he first arrived there – by pines. “Where we have had an opportunity to
redo a landscape, we have largely made use of indigenous. We have also jealously guarded
our natural rock outcrops and bush clumps, dealing with the encroachment of alien
invaders, and the wild areas have flourished,” comments Nigel.
Trees are
planted on golf courses for a number of reasons relating to both play¬ability and
aesthetics. They protect the privacy of holes, separating holes from each other visually.
They protect golfers from the misdirected shot – safety issues are an important
factor on golf courses. One of the main reasons for keeping the Bluegums at Randpark is to
stop golfers from being hit by balls. Nigel comments that the latter are extremely untidy
trees, dropping leaves, seeds and branchlets and therefore a maintenance headache. In the
interim, more suitable trees are being planted in the foreground and background of these
gums which will replace them once they die naturally. Motor cars on roads or highways
adjoining golf courses are also afforded protection by belts of strategically placed trees
on the perimeters of courses.
Maintenance
has to be a consideration when a choice of tree is made. Nigel comments on the massive
problems caused by the poplars on the course which tend to go on dropping their large
leaves for months and their roots are aggressively invasive interfering with the playing
surface. He says it is not necessary to consider only evergreen trees, as a deciduous tree
which drops all its leaves at the same time is manageable.
Trees also
protect the integrity of the course design and defend the course from golfers who are
inclined to play it incorrectly. They relate to the development of a better strategy on
holes by making it unattractive for the golfer to take certain lines. They increase the
difficulty of the course in their role as hazards.
Ziziphus mucronata
Buffalo Thorn or Blinkblaar-wag-n-bietjie
The Buffalo Thorn is widespread through the northern and eastern portions
of South Africa, occurring mostly in woodland and wooded grassland. It provides sustenance
for fruit eating birds such as Guineafowl and Francolin when the fruit drops to the
ground, while fruit on the tree is relished by Louries, the Burchell’s Cougal and
Meyer’s Parrot. The clusters of yellowish-green flowers attract insects, which in
turn attract insect eating birds.
Nigel
favours the tree for a number of reasons: that it is single-stemmed and has a moderate
spreading canopy; that the tree remains evergreen at Randpark Club and has very
attractive, dark-green, shiny leaves, and that it is hardy. He finds the conspicuous
large, red-brown berries very attractive and the tree produces quantities of these.
He says its
disadvantages on the course are that it is slow growing and in the early stages thorns can
be a problem. Two of its Afrikaans common names relate to its thorns –
‘Haak-en-steek’ refers to the paired spines, one hooked and one straight, while
‘wag-n-bietjie’ means it will hold you back – cause you to
‘wait-a-little’. He advocates keeping the tree to out-of-play areas. It grows
naturally at Randpark in bush clusters, providing a highly ornamental addition to the
grouping with its fruit and shiny leaves. It creates a wonderful backdrop to a couple of
the holes at the club.
Buddleja saligna
False Olive
The tree is indigenous to large areas of the country, growing in most
habitat types except forests. It is common in dry woodland along drainage lines. The
masses of white to creamy-white flowers in large clusters are honey-scented and attract
many species of butterflies and bees.
Nigel finds
it a marvellous tree for screening purposes, as a backdrop plant and for separating tees
from greens, as it is naturally multi-stemmed with a dense, multi-branching crown and an
attractive weeping appearance. He adds that it is useful in areas of the course where the
golfer needs to concentrate on the shot and does not want to see any activity.
He likes its
conspicuous bunches of flowers, the fact that it is evergreen (or evergrey, as he says)
and that it is very hardy. He calls it a zero maintenance tree.
He finds the
deeply fissured old bark aesthetically pleasing and says its wood is very hard which makes
it golf ball resistant: it incurs no golf ball damage. He points out that certain trees
like the softer wooded Combretums can suffer extensive damage if they are hit when they
are young: “A nasty hit can shut down the growth of such a tree or take the leader
out completely and damage the shape of the tree.”
Kiggelaria Africana
Wild Peach
The tree grows naturally largely in the eastern parts of South Africa, but
extending down into the Western Cape and some way up the West Coast. It is a tree of
evergreen forests, rocky outcrops and wooded grassland along drainage lines. Its leaves
vary in texture depending on whether it is growing in shade or full sun. The bright
orange-red seeds are oil-rich and they attract many fruit-eating bird species. It is the
host plant to the Garden Acraea butterfly.
Nigel
favours the tree because it is single-stemmed with a moderate round canopy and its
attractive foliage has a distinctive golden tinge in sunlight. It is semi-deciduous but
drops only a few leaves each season and is certainly not a maintenance problem. It is an
extremely hardy tree.
It can be
used anywhere on the golf course and occurs in the natural bush clusters at Randpark. It
should, in Nigel’s opinion, be planted in tight strategic groupings which can be
brought into play along fairways or in other areas on the course – also, it is
necessary to plant a group, and not just a single individual, to make sure that both sexes
are present, as the sexes occur on different trees (in other words the tree is dioecious).
There is an example at Randpark of a large Wild Peach growing in conjunction with one or
two other trees functioning to separate a tee from the green of the previous hole.
In
Nigel’s opinion, the only drawback of this tree is its vulnerability to the Garden
Acraea caterpillar which can strip younger trees completely. The tree, however, puts out a
new flush as soon as the caterpillars have pupated. Roger Innes, who is doing his
learnership at Randpark as part of his BTech in Turf¬grass Management and who is
knowledgeable about indigenous trees, comments that he has only seen the caterpillar
decimate the foliage of young plants. He says the caterpillars love new growth. It is also
Nigel’s experience that the caterpillars have no visible effect on older trees.
Rhus lancea
The Karee
This tree (chosen as Tree of the Issue for larger landscape plantings in
UGF’s Jan/Feb issue, 2004) has a widespread distribution in the central areas of
South Africa, extending down to the coastal region of the Eastern Cape. It grows mostly in
Acacia woodland along drainage lines and in virtually any soil type. It attracts
fruit-eating birds. It has the wonderful Afrikaans alternative common name of
‘Hoenderspoorkaree’ (chicken footprint Karee) – one glance at the
tri¬foliate leaf will tell you why.
Nigel has a
great love for this tree. He says its advantages on the golf course are that it is
naturally single-stemmed with a dense round canopy and, like Chris Bowden who chose the
tree previously, he is taken with its coarse, dark-brown bark and the rugged look of its
trunk and branches. An important factor is
that its bark makes it resistant to golf ball damage. He likes the colour of its new
foliage and its slightly pendulous growth habit. The fact that it is “usually
evergreen” means that it is not a serious maintenance problem, although he does find
that it is inclined to shed leaves in very dry periods and this usually happens just after
winter. He remarks that it is very hardy and medium to fast growing and does well in clay
soils. One of its most important assets is that it tolerates brushcutters!
Nigel says
it does have a few disadvantages and these are that it is low branching, which makes it
difficult to get grass cutting equipment under its branches when it is brought into play,
as it is along the above fairway of the Randpark course. He says it manifests a certain
amount of dieback in dry weather and can look a little raggedy in early spring. Randpark
does a clean-out of these trees annually. Lastly, a little red wasp (he does not know the
species name) utilises it as a host plant and has the nasty habit of stinging both
maintenance personnel and players alike.
-----
A shared solution for waste disposal
The new
Karwyderskraal regional landfill site in the Botrivier valley, southern Cape, and
associated waste transfer stations in Hermanus and Kleinmond, set a number of precedents
that are instructive for municipalities dealing with the problems often related to solid
waste disposal.
In an
overview of the project, Rob MacFarlaine highlighted some of its distinguishing factors.
MacFarlaine was with Arcus Gibb when the firm acted as project managers and consulting
engineers on this integrated waste management initiative.
*
The Karwyderskraal
regional landfill, which began operating in 2002, was the first ‘greenfield’
landfill site to be permitted in the Western Cape under the new environmental laws and
landfill design requirements.
*
The new regional and
local facilities provide a shared solution, and shared costs, for the regional Overberg
District Municipality and local Overstrand Municipality.
*
The linking of
localised waste transfer stations to a regional waste disposal site encourages the local
municipalities and ratepayers to reduce waste quantities in order to reduce their costs of
disposal.
*
Restricted usage of
the regional landfill site, which limits access to authorized vehicles only and excludes
any recycling processes, eliminates the negatives of high traffic, illegal dumping,
scavenging and crime often associated with landfill sites.
*
Careful siting and
design of the waste transfer stations in Kleinmond and Hermanus, minimises their visual
impact on the environment.
*
An analysis of waste
management operations enabled the municipalities and the public to understand the real
costs of this service and an evaluation of public and private sector competencies and
costs identified the most cost-effective operational solution.
Background
In 1985 the Department of Water Affairs and Forestry (DWAF) instructed the then
Hangklip-Kleinmond and Greater Hermanus Municipalities to close their existing ‘dump
sites’ as they did not meet the minimum standards. The sites were overloaded,
polluting ground and surface water, and posed a health hazard to residents. Although DWAF
required that the old sites only be closed as soon as a replacement site or sites had been
developed, the difficulties of identifying suitable alternative sites were not
anticipated. This scenic coastal strip of the southern Cape is located in a sensitive
environment and presents a geology generally unsuitable for landfills.
When
municipal boundaries were altered and the new Overstrand Municipality came to include the
towns of Rooi Els, Pringle Bay, Betty’s Bay, Kleinmond, Hermanus and Gaansbaai, it
was recognised that all these fast-growing holiday towns along the coast suffered similar
waste management problems. It made sense for the Overberg District Municipality and the
newly formed Overstrand Municipality, to fund a collective, regional solution. The local
towns realised that by combining their resources they could benefit from economies of
scale and so implement a solution that would have been unaffordable to them individually
and would benefit the wider community.
Feasibility studies
Initial feasibility studies investigated a number of waste disposal options,
including incineration, composting and long distance (150 km) haulage by road or rail to
one of the existing disposal facilities near Cape Town.
The finally
agreed option of a suitably located regional landfill site with associated waste transfer
stations in the main towns, was supported by a number of factors, including the long
distances between the main towns in the Overstrand, and the extreme variability in the
quantities of waste generated – which results from a high influx of visitors over
weekends and holidays that can see the populations more than tripling and household and
commercial waste output doubling.
Even though
disposal by landfill is not ideal, and in initial discussions with the residents there was
a strong ‘not in my back yard’ factor at play, residents and community leaders
recognised that a linked local-to-regional solution was the most viable and they supported
a progressive waste management strategy.
The search
for an appropriate location for a regional landfill site was restricted to the Botrivier
Valley which is underlain by suitable geology. Of the ten sites investigated, which
included quarries and other disturbed areas, only one was found to be suitable. Overall,
the process of public consultation, site selection, Environmental Impact Assessment, land
rezoning, land purchase and permitting, took nearly four years to complete. Detailed
design, tendering and construction were completed within a further 18 months.
Landfill design
The Karwyderskraal regional landfill site – a ‘greenfield’ site
– is located on a 100 ha portion of former farmland which was de¬graded and was
assessed as having low agricultural potential. Only 40 ha of the site are to be used for
landfill; this is calculated to provide a 50-year lifespan.
By designing
the landfill to introduce two-hectare waste cells in phases, each to be followed by
extensive landscaping and screening, consulting engineers Arcus Gibb sought to minimise
its physical and visual impact on the surrounding environment.
Civil works
entailed the construction of surfaced access roads, a 6km water pipeline and stormwater
and leachate management systems. In addition, the first two-hectare waste cell was
constructed, with provision of a cover material stockpile sufficient for three years.
Preliminary landscaping and screening was completed and an automated irrigation system
installed to facilitate ongoing rehabilitation. The site is securely fenced and offices,
workshops and weighbridge buildings were designed to minimise their visual impact in this
rural setting.
The landfill
site is across the Bot River from the prestigious Arabella Country Estate and Hotel.
Although it is clearly visible from the estate, it looks like farmland and the only
noticeable building like a small farm building.
One of the
conditions of approval for the project, in terms of the EIA, was that it should be
accessible only to authorised contractors running vehicles with large loads. It is not
open to the public and no recycling is carried out at this site. This restriction is aimed
at limiting the impacts on the surrounding area and preventing the excessive road traffic,
illegal dumping and scavenging that are typically associated with landfills.
A further
benefit of restricted usage of the landfill, is that it provides an incentive to the local
municipalities – which remain responsible for all waste generated in the main towns
– to implement waste minimising practices in order to limit their waste transport and
disposal costs.
Design of transfer
stations
With Arcus Gibb as the consulting engineers, Cape Town based Adler Price
Architects designed the waste transfer stations that have been built in Hermanus (16 km
from the Karwyderskraal landfill) and Kleinmond (25 km), and a third which is planned for
Betty’s Bay.
The transfer
stations were required to provide convenient, hygienic and safe, localised waste
offloading facilities for use by the municipal waste collection services and the public.
A simple,
efficient waste transfer system was needed, one that would accommodate normal and peak
volumes of different waste types, that would be easy to manage and flexible enough to
incorporate different processes of waste separation and recycling.
The 30 m3
(eight tonne) open-bin roll-on roll-off system proved economically feasible for the waste
transfer operations. It also allows for different waste types to be accommodated and meets
the off-loading requirements of various users.
In the
design of the waste transfer stations, special attention was given to the aesthetics of
the buildings and their layout on site, with one of the main design criteria being to
minimise their visual impact in their respective surroundings. This proved quite a
challenge alongside the further briefed requirements: to provide enclosed space for the
offloading, sorting and dumping of waste to skips; to ensure that through all weather
conditions of high wind, heat and winter rainstorms, the waste would not become wet or
malodorous or be scattered by the wind; and to allow for the manoeuvring of various types
of vehicles, including dump trucks with a six metre height clearance (with load bed
raised). In addition, the transfer stations had to be easy to operate, requiring minimal
supervision and maintenance, and easy to keep hygienically clean. The main office and
offloading area was required to provide good visibility of all operations. Site security
and access control were essential.
The transfer
stations incorporate a raised access platform and offloading area, with the open waste
skips housed at a lower level, adjacent to a transfer yard. The floor level of the
drive-in offloading bays is flush with the top of the skips at the lower ground level.
Because of the operating space required by the waste handling vehicles, the buildings
stand 11,5 m high in places. Robust materials were essential to ensure durability in these
hardworking facilities. The hangar-like structures, erected on floors of reinforced
concrete, are steel framed and clad with profiled steel sheeting. In some areas,
flush-pointed brickwork and a cementitious coating introduce a different scale and
texture.
Modifications
to the design were made at the respective sites where, as Neville Adler says, care was
taken to articulate and break down the form of the building using colour, massing and the
texture of materials. In both towns, the sites for the transfer stations were chosen after
numerous options had been assessed.
The Hermanus
transfer station is located in an industrial area, adjacent to housing, on a site that is
in part old landfill. This complicated the foundation work required for the new buildings.
Extensive fill had to be imported to establish the raised access and building platform.
The
Kleinmond transfer station is adjacent to the main entrance to the town on a site that had
been used for evaporation ponds and is entirely exposed to the aggressive climate and to
general view against the mountain backdrop. Founding conditions were poor but the gradient
of the site was used to advantage in establishing the different floor levels of the
transfer station and to reduce its visual impact. Here too, the modulation of form and
judicious use of colour help to downscale the impact of such a large building.
In both
cases, the buildings are oriented to take account of the prevailing wind direction and
they are positioned on their sites to allow the standard waste transfer operations to be
linked to further waste sorting, recycling and recovery processes in future. Provision is
also made for compaction equipment to be accommodated if required.
Separate
uncovered areas are provided for bush waste offloading and chipping, and for
builders’ rubble. Bush chippings are reused in composting, landscaping and other
applications, and the rubble is reused either locally in civil construction works or at
the landfill for road cover or wearing courses or stabilisation and levelling of the
landfill itself.
Sorting and recycling
At present households in Hermanus are provided with clear plastic bags for dry
refuse that can be recycled – such as glass bottles, cans and plastics. These bags
are collected with the other refuse by the municipal services and taken to the waste
transfer stations where they are sorted for recycling. Walker Bay Recycling has set up
operations at the waste transfer station.
A similar
system is due to be implemented with households in the Kleinmond area this Easter,
although a permanent recycling operation is yet to be established at the Kleinmond waste
transfer station.
MacFarlaine
says there is still a long way to go in developing waste minimisation practices and viable
recycling businesses. But he adds that there is a growing awareness of their benefits, not
least in the savings secured for local authorities and ratepayers. These are achieved in
reduced landfill costs and lower demand for dump space, reduced transport and handling
costs and, in a broader sense, reduced road damage and environmental degradation.
All waste
that is not recycled is transferred to the Karwyderskraal landfill site.
Adler says
that with the new facilities in place and the increasing awareness that refuse removal
costs impact directly on municipal rates, it is hoped that recycling and composting of
waste at source, or by each household, will become the norm.
“We may
have some way to go before households have their own worm farms, as is happening in
Australia, but this project demonstrates the tangible savings achievable through sensible
management of waste by business, householders and local authorities.”
Since the
transfer stations began operating, together with the Karwyderskraal landfill, in 2002,
reports from the municipality, the public and visiting interested parties have been
favourable. The convenience and efficiency of the new facilities have encouraged their use
and illegal dumping has reportedly declined significantly.
Operations contracts
MacFarlaine emphasises that one of the important benefits of the project was
that it enabled the local authorities and the public to assess the real costs of waste
handling and disposal. Before going to tender for the operations contracts – which
included the operation of the two transfer stations, bush chipping, haulage of waste
containers to the landfill site and operation and maintenance of the landfill site –
both the Overberg District and the Overstrand Municipalities evaluated their internal
capacity and related costs for the provision of these services. They defined a series of
benchmarks against which private sector tenders could be assessed.
At present,
the Overstrand Municipality staffs and supervises the transfer station operations. The
bush chipping contract was awarded to a local contractor on a short-term basis and the
Overstrand Municipality contracted a private sector company, Millennium Utilities, to
handle the haulage of waste containers from the transfer stations to the landfill site.
The same company was also contracted by the Overberg District Municipality, which is the
owner and permit holder for the Karwyderskraal landfill site, to operate and maintain the
landfill.
“The cleanest
town” in the Western Cape
Last year the Overstrand Municipality won the award for the cleanest town in
the Western Cape. MacFarlaine says this achievement can be attributed to the work done by
a range of environmental interest groups and organisations that are active in the area
and, in part, to the new infrastructure provided by the Overstrand-Overberg waste
management systems.
-----
The air that we breathe
Comment
on the draft Air Quality Management Bill
The new Air
Quality Management Bill drafted by the Department of Environmental Affairs & Tourism
(DEAT) to replace the Air Pollution Prevention Act (APPA) of 1965, shifts the focus from
limited source-based emission control to management of ambient air quality. While welcomed
by some parties, because it promises a clear framework for dealing with air pollution and
will establish enforceable legislation, the bill has provoked opposition from the civil
society lobby and has raised some concerns regarding the practicalities of implementation.
Itumeleng
Mabalane, Director Air Quality Management at DEAT, says the Department is currently
reworking the content of the bill, taking account of the comments from all stakeholders.
Revisions to the bill are expected to be complete by June this year. Anticipating that the
revised bill would then be accepted by the stakeholders, Mabalane envisages that the new
Air Quality Management Act could be on the statute books by mid 2005.
Comment on
the draft bill was presented to the Parliamentary Portfolio Committee on the Environment
by, amongst others, organisations representing different industry sectors, such as the
Chemical and Allied Industries Association (CAIA), the Chamber of Mines, and the Refinery
Managers Environmental Forum; by the National Association for Clean Air (NACA);
groundWork, representing a wide range of civil society organisations; and the
Environmental Law Committee of the Law Society of SA.
In
NACA’s view the draft bill introduces a good approach in principle and effectively
addresses the fundamentals of air quality management. The Association’s comments
related mainly to the means and methods of implementation.
Gerrit
Kornelius, president of NACA, and Air Quality & GHG Strategy Advisor at Sasol’s
SHE Centre, says that a new act to manage air quality is definitely needed. He says the
old APPA has been largely discredited, partly because it was not legally enforceable, as
it presented guidelines rather than strict regulations on air quality controls, and also
because in many instances it has simply not been applied.
Kornelius
adds that there has been a lot of progress made in air quality management – in
systems, technologies and equipment – since 1965 and the bill takes account of this.
“The
old APPA was intended primarily to control industrial emissions,” says Kornelius.
“Although it made provision for ‘smoke-free zones’ – where the
domestic burning of coal was prohibited and which were declared in some areas – in
many areas this provision was not even applied, let alone enforced. Nor did the old act
address emissions from vehicles, which are included in the new bill.”
Kornelius
explains that Schedule 2 of the APPA listed industrial processes which required permitting
by DEAT. The Department used informal guidelines for controls on emissions from scheduled
processes and for ambient air quality. Permits issued to industry could include specific
conditions for the control of emissions. Generally, these were defined as the ‘best
practicable means’ for such control – a term which itself dates back to the
British Alkali Act of 1865.
The APPA
allowed for the best practicable means to vary per region, depending on the concentration
of industry and population, but in practice this provision was not applied and the
mechanisms for its enforcement were weak. So-called ‘hotspots’ have developed
– such as the Vaal Triangle, south Durban, Milnerton in Cape Town, and Middleburg and
Witbank in Mpumalanga – where air pollution problems peak because of an agglomeration
of industries, a related concentration of people attracted to work opportunities in the
area, very often in parallel, a high level of coal use for domestic fuel, and a greater
number of vehicles.
The new bill
takes a much more comprehensive approach, looking first at the setting of ambient limits,
then addressing emissions generated by industry, vehicles and domestic fuels – all of
which contribute to ambient air quality, and including limits on odours and noise. It also
proposes stricter controls – to be formalised in a regulatory framework of standards
for ambient air quality – and appropriately severe penalties for offences.
Licensing
Industries conducting activities which generate emissions that are likely to
have a detrimental effect on human health or the environment (which at present are those
industries listed in Schedule 2 of the APPA) will have to obtain a licence under the new
act. Those companies that currently hold Registration Certificates, issued under the old
act, will be required to apply for new licences. While existing certificates will be
deemed equivalent to provisional atmospheric emission licences for a period of two years,
the holding companies will be required to apply for a new licence within one year of the
new act being promulgated.
The licence
application necessitates an Environmental Impact Assessment and a public participation
process. Furthermore, licences will not be granted for an indefinite term but will be
subject to renewal at intervals that will be individually determined. On reapplication,
stricter standards may be imposed if, for example, the concentration of industry in an
area has increased, and the EIA and public participation processes will have to be
repeated. These requirements could become quite onerous for industry. However, according
to Kornelius, industry’s main concerns in this regard, lie with the additional costs
that could be imposed by specific conditions of a licence.
“A
licence may include conditional requirements such as specific emission controls and
constant monitoring of those emissions along the fence line, or on stacks. Monitoring is a
costly exercise and equipment, especially on-line emission monitoring equipment, is
difficult to maintain.”
Managing air quality
The aim of the new bill is to restore and protect the quality of air, taking
into account the principles of the National Environmental Management Act (NEMA). South
Africa’s obligations to its neighbours and at a broader international level, in terms
of air quality management, are also an important focus of the bill.
A national
framework of norms and standards dealing with ambient air quality and emissions from
point, non-point and mobile sources is envisaged.
A national
air quality management committee is proposed as an advisory body to assist the
environmental and tourism minister in implementing the new act. In addition, air quality
officers will be appointed at national, provincial and municipal levels to implement and
coordinate air quality management matters in their areas. Administrations at these levels
will have to prepare air quality management plans and report on implementation annually.
Areas where
ambient air quality standards are being exceeded can be declared priority areas and
provision is made for such areas to be managed according to area-specific air quality
management plans and regulations.
Local capacity
Licences will be issued by local authorities and this is another of the key
concerns raised by industry, considering the capacity problems that exist in many
municipalities.
The
Department has pointed out that, constitutionally, air pollution is designated as a
responsibility of local authorities. This makes sense in that air pollution problems and
the levels of control required vary widely in different localities. However, Kornelius
says that NACA has proposed what it calls an “airshed” – as in watershed
– management approach, which would encompass the wider “catchment area” and
could involve local as well as provincial and national authorities. He also makes the
point that, constitutionally too, where local authorities lack capacity, competence or
resources, they can delegate upwards to provincial government. He envisages that airshed
management is bound to happen in practice and suggests that a mechanism for cooperative
governance amongst the authorities concerned is required.
Ambient air quality
versus emission controls
While the general emphasis of the draft bill is on managing the quality of
ambient air, there are also provisions for specific controls on emissions.
Mabalane
points out that the bill’s focus on managing ambient air quality is driven by the
intention to protect the quality of “public air – the air that you and I
breathe” – which is in turn driven by the constitution and the individual’s
right to a safe and healthy environment. He adds that the Department recognises,
nonetheless, that it will seriously have to consider emissions standards, particularly in
the workplace.
groundWork
groundWork is a non-profit environmental justice service and developmental
organisation that seeks to improve the quality of life of vulnerable people in South
Africa, and increasingly in Southern Africa, by assisting civil society to have a greater
impact on environmental governance. The organisation places particular emphasis on
assisting vulnerable and previously disadvantaged people who are most affected by
environmental injustices.
Controlled emitters
The Air Quality Management Bill identifies “controlled emitters”,
which could be cars, for example, and makes provision for national emission standards to
be applied to different categories of controlled emitters. Fuel stations are another
possible example; they could be defined as a category of controlled emitters because of
their release of volatile organic compounds. As such, they could be required to meet
specific national emission standards.
Classified emitters
There is also provision in the draft bill for control of emissions from
specific sources or classes of emitters. This means that certain sectors of industry
– the steel industry, for example, or the refinery sector or the power generation
sector – nationally, or regionally, could be required to institute specific emission
controls.
In
Kornelius’s view, some degree of emissions control is inevitable. “We can only
achieve the standards of ambient air quality sought by using some measure of direct
control on the sources of emissions,” he says.
The civil
society network is arguing for stronger controls on emissions at source rather than in the
ambient air. groundWork’s submission on the draft bill to the Parliamentary Portfolio
Committee was supported by 40 civil society organisations. As an environmental justice
organisation, groundWork provides technical, campaigning and networking support to
communities affected by industrial pollution. It works with community groups living in
Sasolburg, Boipatong, Secunda, Richards Bay, south Durban, and Table View in Cape Town.
groundWork cites the bill’s focus on regulating ambient air as one of its main
concerns, saying that although this is an important activity, it is long term and will
require a huge financial commitment from government.
Ardiel
Soeker, coordinator of groundWork’s Air Quality Project, says that communities living
next to big polluters like Sasol, Caltex, Iscor, Foskor, Engen and Sapref, believe that
the bill should pay special attention to reducing pollution at source – by setting
emissions standards. The organisation also points out that “a pollution release and
transfer inventory”, which it sees as key to setting emissions standards and managing
pollution, is absent from the bill.
In
groundWork’s view, the bill provides very few guarantees to ensure the protection of
people’s health and the environment. “Instead,” Soeker says,
“officials are given wide discretionary powers and very little guidance on exercising
their discretion.” He warns that this could make certain provisions of the bill
constitutionally invalid.
Regarding
the argument for controlling emissions at source Kornelius comments that NACA is in favour
of the bill’s “outcomes based” ambient air emphasis because it will impose
standards and controls where necessary rather than universally. “If we were to work
with prescribed emissions standards,” he says, “we could find those standards
being imposed even where ambient air quality is perfectly good and the emissions standards
are neither applicable nor necessary. On the other hand, a ‘one-size-fits-all’
emission standard may not ensure that the reductions in some areas are sufficient to meet
ambient objectives.”
He
reiterates that, in practice, it is inevitable that the new bill will apply emissions
standards in certain areas and certain sectors anyway, but these would differ in different
regions. “In the Vaal Triangle, for example, we would need to implement measures to
reduce the use of coal as a domestic fuel. Research has shown that this alone accounts for
about 50% of the particulate matter in the air in this area. We would also need to address
the problem of dust from unpaved roads, as well as pollutants from mining and other
industries.”
As this
example illustrates, the effective management of air quality will require collaboration
across different departments. While DEAT is the lead agent driving the new bill, the bill
does make provision for this kind of interdepartmental collaboration. The Department of
Transport may need to look at new traffic controls in urban areas; the Department of
Minerals & Energy is already looking at means to reduce domestic coal smoke, and has
instituted new specifications for liquid fuels, which will be in force by 2006.
Ambient air quality
standards
A further concern voiced by groundWork is that the bill does not set any time
frames for establishing ambient air standards or for developing the envisaged national
framework for air quality management.
In parallel,
the question of the practical means to measure air quality arises, although some work has
already been done on this.
Kornelius
reports that some local authorities, such as the eThekwini Metro, have a number of ambient
air quality measurement stations in operation. The Johannesburg Metro is also installing
such stations, and at provincial level, so is Gauteng’s Department of Agriculture,
Conservation, Environment & Land Affairs. (In the Nov/Dec 2003 issue UGF reported on a
new air pollution monitor set up in Bellville South, Cape Town. Strongly supported by the
Bellville South Environmental Forum, the monitor was funded by local industries and is
managed and maintained by the local authority. Daily data is made available on the City of
Cape Town’s website.)
In industry,
some companies have been monitoring air quality within their operating localities over
many years. Eskom has been doing so for about 20 years, Sasol for the past 10 years and
other companies such as Sappi and Palaborwa Mining also have air quality monitoring
systems in place. However, there is no formal co-ordination amongst these different
initiatives. A uniform system of measurement and reporting will become essential with the
new act in force; a national database of ambient air quality measurements will be
required.
NACA has
contributed to the drafting of ambient air quality standards – a task assigned to a
select technical committee at the SABS. But this is no simple matter – to determine
the appropriate standard – or acceptable level – for a great range of air
pollutants.
“One
cannot work with just a number,” says Kornelius. “A level of 125µg/m3
of SO2, for example, may be permissible with respect to human health, but one
also has to determine whether this should be measured at, say, hourly, daily, or weekly
intervals, and over what period of time it should be implemented.”
The numbers
being used by the appointed technical standards committee are based on guidelines issued
by the World Health Organisation. The WHO guidelines, in turn, are derived from
epidemiological studies that have investigated the state of health in sample populations
in various regions of the world.
“However,
where the number may represent the ideal in terms of air quality,” Kornelius says,
“if the present situation does not meet this requirement, various factors have to be
taken into account if changes are to be made to improve the air quality. Impacts on
business economics, for example, and on job losses or gains, would need to be considered,
together with other social and environmental impacts.”
NACA
suggests that a “schedule for implementation” is required, to factor in these
various impacts and to determine a time period over which the situation should be
ameliorated. This is one of the main areas where the Department, in NACA’s view,
needs to do more work.
At present
the bill adopts the old APPA guidelines as a schedule for ambient air quality standards.
Although this is proposed only as an interim measure, interim measures create uncertainty
and there is much better information already available – in the WHO guidelines for
instance. “These, together with a schedule for implementation, which would guide the
process of change and determine time plans – over three, or six, or ten years –
to rectify problematic situations, would make the new act more effective,” says
Kornelius.
He does not
envisage that this additional work, if it is done now, would delay the passage of the bill
and he adds that it will be difficult to quantify costs of implementation until such
programmes are in place.
Clean air and GHGs
Asked about the air quality management bill and its relation to cleaner
industry processes that are being encouraged to reduce greenhouse gas emissions and limit
climate change, Kornelius explains that the focus is different.
“The
new bill is concerned with people’s health and the immediate environment. It deals
with pollutants such as nitrogen dioxide, sulphur dioxide, nitrogen oxide, lead, dust and
others, whereas the greenhouse gases include CO2, methane and substances like nitrous
suboxide, which are not immediately toxic but are harmful in the broader environment.
Nonetheless,” he says, “the new act does also provide for the monitoring of
GHGs.”
The National
Association for Clean Air
NACA is an independent, interdisciplinary, non-governmental organisation
concerned with promoting air quality management. It has about 400 members, including
individuals, companies, local authorities and statutory bodies. The Association is
governed by a national council and is active across the country with regional branches in
the Eastern Cape, Western Cape, KwaZulu-Natal, Soweto, Vaal Triangle and the Northern
region. It is a corporate member of the International Union of Air Pollution Prevention
and Environmental Protection Associations (IUAPPA) based in the UK. It functions as an
authority on air quality in SA, and plays an important role in sharing knowledge,
distributing information and organising events concerned with air quality.
-----
Closure and redevelopment of an
industrial site
Kynoch
Fertilizer production facility, Milnerton
Operation of
large industrial sites will implant a ‘footprint’, not only physically onto the
actual site, but also socially and economically onto the surrounding community. Closure of
operations and redevelopment of industrial sites requires attention to business,
environmental, social and regulatory issues. Co-operative governance and decision making
between all role players, including employees, clients, local community, regulatory
agencies, developers and new tenants, is essential when undertaking such a programme.
Industrial
plant closure is a multi-faceted process requiring several years of preplanning involving
a multi-disciplinary project team of both in-house and external specialists, assisted in
their decision making by a number of local government authorities and public interest
groups. Managing the closure process itself requires specific attention to detail to avoid
any negative environmental impacts. Here are some of the processes followed, environmental
management actions instituted and lessons learnt through following a co-operative
governance process for the closure of and future vision for the old Kynoch Milnerton site.
Operation and setting
The Kynoch Fertilizer factory operated on the corner of Koeberg and Plattekloof
Roads in Milnerton, north of Cape Town, from around 1966 to 2003 (Figure 1). As a
consequence of economic pressure, cessation of fertilizer production commenced, in a
phased manner, in 1999 and will terminate entirely in mid to late 2004, once liquid
fertilizer production is stopped.
The core
operations of the factory were to produce nitrogeneous fertilizer; specifically limestone
ammonia nitrate (LAN). In 1986 liquid fertilizer production commenced, followed by bulk
blending of solid NPK fertilizers (1998). Fertilizer production was supported by various
services including the provision of utilities (steam, air, water, etc), maintenance,
laboratories, warehousing, bagging and dispatch and railage, along with effluent, safety
and environmental management.
The site is
60ha in extent with approximately half this area being covered by operations. The
surrounding land use is heavy and light industrial, and sportsfields are in evidence. The
average elevation of the site is ~16m above mean sea level and the topography can be
described as flat, being dissected by the south-east to north-west flowing Duikersvlei
Stream (Figure 2). This stream exits the site on the Koeberg Road boundary and joins the
Montague Gardens stormwater canal. It then joins an earth canal paralleling the Rietvlei
and discharging into the Milnerton Lagoon near the Otto du Plessis bridge. This canal
overtops in winter into the Rietvlei.
The local
geology comprises between 2-8m of unconsolidated marine clayey-sands overlying weathered
Malmesbury Shale, grading to fresh shale. Groundwater is shallow at between 0m (along the
stream) to ~2m depth. The regional groundwater flow direction is north-westerly and flow
velocity is variable due to the formation of heterogeneity and anthropogenic influences.
Operational history and
planning for closure
Closure of an industrial operation should not be seen as ‘the end’ of
a site’s use but rather an opportunity for new initiatives.
The factory
was commissioned in 1966 by Fisons (Pty) Ltd, changing hands a number of times until the
AECI acquisition in 1988. It produced a world class quality product and enjoyed
significant market protection – partly from the government policies of the time and
partly because of its physical proximity to the Western Cape market. Although the price
control protection fell away in 1984, the factory continued to be profitable – a
position which was strengthened in 1986 with the introduction of liquid fertilizer
production. About 250 people were directly employed and between 100-200 were indirectly
employed via support industries and services.
In 1996
business declined due to a large over-supply of ammonia in South Africa, as a consequence
of Sasol’s oil from coal ammonia by-product, and reduced world demand. This resulted
in closure of the ammonia plant in 1998 in an attempt to solve the over-supply situation.
AECI subsequently decided it was time to withdraw from bulk chemical (fertilizer)
manufacture and the production of LAN ceased in 2000. AECI sold its Kynoch business to
Norsk Agri and operations were reduced to NPK blending and liquid fertilizer production.
Closure
planning entailed a trade-off between managing the cost of the closure whilst meeting
legal, moral and ethical requirements. AECI adopted an approach which it is believed was
both co-operative with all Interested & Affected Parties (I&APs) and, in the long
term, sustainable.
Co-operative
in that:
*
Employees were
counselled, trade unions were consulted, employees were given outplacement education and
generous severance packages, and some attempts were made to find them alternative
employment.
*
Various local
authority and government departments were consulted regarding closure and both short and
longer-term environmental management actions.
*
The public was made
aware of closure plans via a series of public meetings.
*
All the I&APs were
made aware of the prill tower demolition, which received nationwide media coverage and
generated funds for charity.
Sustainable
in that:
*
Although jobs were
lost, ultimately re-development of the site will provide an estimated 25 jobs/2500m2
erf, and approximately 4 000 jobs should eventually be created.
*
The site will be
subjected to an agreed (with I&APs) remediation programme where required.
*
The new development
will be managed via a Property Owners Association subject to strict conformance with
environmental guidelines according to Environmental Management Co-operative Agreement
(EMCA) principles.
*
Special mention must
be made of AECI’s approach to the removal and disposal of asbestos sheeting during
the demolition. This approach, in all likelihood, constitutes a first for South African
industry.
The above
closure plans have involved a hands-on, managed approach throughout. This should be
compared to that of simply locking the door, avoiding consultation and employing a
contractor to reduce everything to ground level.
Managing the
environmental footprint
The ‘environmental footprint’ can be defined as, ‘the mark or
impression left on a site by the activities that occur or have occurred on that site over
time’. It defines the condition of the land and tends to concentrate on the surface
and subsurface environment. Characterisation of the condition of the land commenced in 2
000 and a number of investigations have since been carried out at varying levels of
complexity, each being driven by the findings of the previous and the need to meet
regulatory objectives, so as to enable safe release of the land. The types of generic
activities undertaken have included the following:
*
historical review
– what happened, where and when, incidences, changes in plant and procedures, etc;
*
intrusive
investigations – soil, surface and groundwater;
* contamination
management actions – environmental awareness, source control, excavation, sorting,
safe disposal, hydraulic control, bioremediation, subsurface barriers, in situ flushing,
attenuation and monitoring;
*
communication and
feedback – to local interested parties and the authorities.
For the
review to be successful, two requirements need to be fulfilled: there needs to be full and
open co-operation between all the parties, and the review must be dynamic and on-going.
Co-operation
between remaining staff and those responsible for closure and demolition of an industrial
site is vital to ensure that the environmental footprint does not grow in size and impact.
For the Milnerton site a process of illustrative lectures, followed by site walkovers and
frequent site screening audits, was put in place to raise environmental awareness and
ensure that potential sources of further impact were managed.
Poor quality
groundwater emanating from the Factory Area and seeping (Figure 2) from the base of the
embankment along the Duikersvlei Stream was identified as being of particular concern
since the stream flows off-site in a south-westerly direction towards the Rietvlei and
Milnerton Lagoons.
A subsurface
barrier with associated interception drains and abstraction sumps was identified as being
the most practical and cost effective method to manage this seepage. The barrier extends
over a distance of 270m and to an average depth of 3m below ground. Monitoring since
installation has shown a marked improvement in the quality of the Duikersvlei Stream water
leaving the site. Prior to installation, the average annual total nitrogen concentration
at the off-site discharge sampling point was 768 mg/l, with a peak concentration of 1 991
mg/l. Since installation, the average annual concentration is <200 mg/l with the City
of Cape Town’s pollution control officers measuring an average Total N of 151 mg/l in
2002. Other initiatives are currently underway to reduce the concentrations further and to
enhance the natural attenuation capacity of the impacted shallow aquifer throughout the
Factory Area.
Co-operative governance vs co-operative management
Is it ‘co-operative governance’ we need, or is it ‘co-operative
management’ through agreement?
The Preface
to the EMCA Draft Guidelines states: “To meet the challenges of sustainable
development, business and industry will need to achieve significant improvements in
resource efficiency and pollution reduction, while at the same time meeting increasing
demands for job creation and poverty alleviation”. It continues: “The long-term
achievement of a sustainable economy in South Africa will require us to revisit the
current industrial development path, not only in terms of production processes, but also
in terms of existing policy structures and the nature of interaction between government,
industry and NGOs”.
The biggest
challenges facing South Africa are job creation and poverty alleviation, which go hand in
hand. Meeting these challenges is essential to maintain and improve our socio and
biophysical environment. We need to identify opportunities that can assist us to meet
these objectives and then ensure that the right structures are in place to facilitate the
process of realising these opportunities. The EMCA guidelines have potential to provide
structure for dialogue in this regard.
Where do
opportunities lie in the industrial sector? Many vacant and abandoned facilities exist in
the older industrial areas of our larger cities, especially in the traditionally light to
medium engineering sector. The implications of this situation can be summarised as
follows:
*
Inefficient use of
land and municipal services within inner city areas.
*
Possible environmental
impact in the form of latent contamination.
*
Loss of job
opportunities.
Closure of
industrial operations should not be seen as ‘the end’ of a site’s use but
rather as an opportunity for new initiatives. For any co-operative agreement to exist,
there needs to be an ‘initiator’, an interested ‘developer’ and
‘beneficiaries’ – growth fundamentals of a capitalist economy (Figure 3).
The regulators play a dual role for both the ‘closer’ and the
‘redeveloper’. Thus they need to weigh up the pros and cons of both sides
considering what level of capital and resources should be allocated to both the closing
and redevelopment phases to meet regulatory and environmental needs.
The
‘closer’ has a need to protect existing shareholder value and this implies
demolition and clean-up at a realistic cost to achieve a standard where latent liability
in terms of environmental impact is minimised. The redeveloper has the objective of
maximising profits through development of the site. At variance is the point at which each
is satisfied that the other has fulfilled his/her mandates so that land release and
hand-over can happen. Thus, in terms of environmental and future land use needs, there
needs to be a framework within which this point of acceptance can be measured. ‘Green
certificates’ issued by the local authority, similar to electrical and wood borer
certificates, could play a role in transforming brownfield to greenfield sites.
Given that
financial decisions are often the driver of closure and redevelopment, there is a need to
consider opportunities and incentives to ensure that closure of one operation has a
greater chance of realising new opportunities. It is suggested that government authorities
seriously consider encouraging and assisting this process. This could, for example, be
achieved by allowing tax breaks for new developments such as those enjoyed by the mining
industry, where establishment of a trust fund for ultimate remediation purposes receives
tax rebates.
Lessons learnt
Many lessons were learnt and it was also confirmed that correct decisions had
been made upfront. These include the following:
*
The need to appoint
responsible contractors to perform demolition and remediation work and to ensure that
their per formance is managed by instituting required checks and balances.
*
The overall closure
process requires some form of incentivisation of employees who otherwise are obviously
disenchanted with the situation.
*
The need to maintain a
comprehensive record of events – during operation and closure.
*
Certain costs during
operation associated with environmental impact may seem excessive but these should not be
sidestepped – as this may lead to a penny wise, pound foolish situation.
*
Workers handling
asbestos products need to receive comprehensive training and their performance must be
monitored continually.
*
The need to create a
consultative forum for the affected employees so that all their concerns can be addressed.
*
The need to increase
security – some of those disenchanted with the closure may feel that the company owes
them something ‘extra’.
*
All opportunities for
recycling should be investigated – a significant financial recovery can be made.
*
A phased environmental
characterisation approach should be followed and data interpreted following an
environmental risk based approach.
*
Openness and
transparency should be maintained and the authorities should be involved at all times,
concerning decision making with regard to remedial approaches and objectives.
*
The demolition process
should be controlled to ensure minimum cost concerning timing and the procedures employed.
*
Remediation of land
– legal requirements need to be met whilst controlling cost in a trade-off with the
timing of the release of the land to the market.
*
The development of the
resultant brownfield’s site needs to be controlled – ensuring that costs for
servicing the land are minimised whilst meeting urban planning requirements – both
legal and market needs.
Apart from
the above, the most important lesson for the chemical (and other) industries is to start
planning for ultimate closure at design stage and to continue this throughout the
operational phase.
The above
process calls for co-operative decision making with all I&APs. Although it could be
argued that responsible governance is non-negotiable, it is suggested that in the case of
industrial site closure and redevelopment, this should be done via ‘co-operative
supervision’, guided by the EMCA approach.
Article
based on the paper given at the IAIAsa Conference on Co-operative Governance in September
2003, authored by Ritchie Morris of Morris Environmental & Groundwater Alliances;
Martin Burr of Heartland Properties (Pty) Ltd; and Wilna Kloppers of the Western Cape
regional office of the Department of Water Affairs and Forestry.
-----
Unicity Courtyard
Gardens
Exhibiting the
unique flora of the Cape
Low
maintenance, water-wise landscaping
The choice
of a simple basic design and hard materials creates a sense of continuity throughout the
seven courtyard gardens of Cape Town’s Unicity building, while the diverse plant
palette varies from courtyard to courtyard featuring plants related to different biomes
– fynbos, succulent and thicket/bushveld, reflecting a distinctive local and regional
Cape character.
The gardens
were designed by Marijke Honig of Think Ecologic in association with architect Bruce Beyer
and the landscape contract was executed by Eco Creations, who won a South African
Landscaper’s Institute Gold Award for the project in 2003. Horticulturist Fiona
Powrie gave input into plant selection, soil mixes and planting techniques, and the design
of the drip irrigation system was done by Phillip Botha of Cape Water Plants. The team was
briefed by and engaged with project architect Pedro Roos during detail design stage. The
client evinced an open-minded approach to the experimental nature of aspects of the
landscape work.
Landscape design
concept
The addition of a sixth floor to the podium block of the Unicity building on
Cape Town’s foreshore, previously known as the Civic Centre, incorporated seven open
air courtyards allowing an influx of natural light and air into the building. The
landscape designers were careful to ensure that the elements of the courtyard gardens were
not in conflict with the architectural language.
The simple
design concept comprised gravel gardening with a diversity of indigenous plants. The
undulating gravel landscape was a response to the bold horizontal and vertical planes of
the courtyard architecture. Aside from the ornamental and greening objectives, long-lived
plants adapted to shallow soils and low water requirements were selected to meet both
environmental and low maintenance objectives.
The concept
was also informed by the practical functioning of the courtyards as places for people to
meet informally during smoke and lunch breaks. Gravel circulation areas were combined with
large planted areas. A layer of decorative gravel, also functioning as a water conserving
mulch, was continued through into the plantings to offset the shape and texture of the
plants – and to ensure that the gardens would always look tidy even when the
deciduous bulbs were dormant. The colour and texture of the gravel in the circulation
areas differed from that used in the planted areas: the red gravel is a by-product of the
diamond mining industry. Shade was provided through carefully selected tree species.
Slatted timber pallets were used to demarcate the doorways into the courtyards.
Due
consideration was given to seating in the original concept, which also included timber
trellises designed to add depth and texture to the courtyard walls by allowing creepers to
green the vertical planes, but eventual budget constraints ruled out these elements.
Subsequently, staff have acquired garden furniture for the courtyards adjacent to their
workspaces and the spaces are now being used as was originally intended.
Plant selection
The Unicity courtyards manifest particularly challenging conditions for the
growing of plants – extremes of sun and shady conditions, turbulent winds which
buffet plants, as well as minimal soil depth because of loading constraints. The maximum
planting medium depth allowed by the engineers was 200mm and the volume was increased by
adding polystyrene balls to achieve a depth of 290mm without the weight increase –
approximately 200mm of soil medium and 90mm of polystyrene were utilised. Indigenous
species which could tolerate a range of environmental conditions and shallow soils were
selected and this included many lesser known species unfamiliar to the commercial
landscaping industry. Many of these were only available from specialist growers and the
National Botanical Gardens, and plants were sourced from as far afield as Worcester,
Robertson and George.
The emphasis
was on foliage colour and texture but in each courtyard there are some plants in flower
throughout the year. There are over 200 species of indigenous plants in the courtyards,
grouped into natural assemblages. The individual ambience of each courtyard is created by
the varied plant selection which provides a showcase of the Cape’s unique flora.
Two of the
courtyards feature typical fynbos plants such as restios, eight species of the aromatic
Buchu, Pelargoniums, some erica species, Aristeas, Euryops and Western Cape bulbs
including: Lachenalia bulbifera, Freesia spp, Chasmanthe floribunda and a variety of
Watsonias. The fynbos courtyards also in-clude Western Cape aloes such as Aloe commixta,
the natural distribution of which is restricted to the Cape Peninsula, and A. succo¬trina
which is restricted to mountain slopes in its natural habitat. The soil mix in these
courtyards is slightly acid and drains well.
The
succulent courtyard displays largely bulbs and a variety of succulents interspersed with
‘thicket clumps’ of Aloe arborescens, Carissa bispinosa, Portulacaria afra
– the Spekboom, one of the most distinctive plants of the succulent thicket –
Lycium and Putterlickia spp. The aloes in this courtyard include A. striata, A. ferox, A.
microstigma and various hybrids. Other succulents are species of Haworthia, Crassula,
Poelnitzia, Gasteria and Faucaria, while the bulbs comprise Lachenalia aloides,
Ornithogalum dubium and species of Strumaria, Haemanthus and Melasphaerula. The soil mix
in this courtyard comprises a larger percentage of clay, as the plants need more minerals.
Four
courtyards display thicket and bushveld vegetation, representing the Eastern Cape and
further afield, and the tree species include: Combretum erythrophyllum, which has retained
a good shape, while Rhus chirendensis has proved a little messy, Cussonia spicata, Dombeya
rotundifolia and Diospyros whyteana. These courtyards include a few cycads and a number of
Aloe, Kalanchoe and Crassula species, such as C. lactea. Shrubs include species of
Carissa, Plumbago, Tecomaria, Barleria and Hypoestes, while the bulbs include Scadoxus
multiflorus subsp katharinae, Veltheimia bracteata and Merwilla (Scilla) natalensis.
Amongst the herbaceous plants are Phygelius capensis, Pelargonium reniforme and Hermannia
pinnata. The renowned Strelitzia regina ‘Mandela’s Gold’ was deemed an
appropriate addition.
The soil mix
in these courtyards is more neutral and slightly heavier than in the fynbos courtyards.
Cone shaped tree guards were designed by the architects using a base made of flatbar to
preclude any possible puncturing of the waterproofing layer.
The
positioning of the plants had to be done according to their shade or sun loving tendencies
and use was made of computer generated shadow diagrams produced by architect Pedro Roos.
Trees had to be positioned at the crossing of underlying structural beams.
Waterproofing and
drainage
A vitally important aspect of the implementation of the landscape works was the
waterproofing and drainage of the concrete floor in each courtyard. The screed was laid to
fall into two full bores in the corners of the courtyard. It was necessary to ensure that
the soil mix on the screed would drain adequately and that the water could move unimpeded
by fines towards the full bores. The waterproofing product Dorken Delta MS 20 was
utilised, which comprises egg-shaped hollows, each with a hole in it to allow for water
flow. This product was covered with a layer of geotextile and then with the soil mix.
Water
filters from the soil through the geotextile, which cleans the water, into the egg-shaped
hollows and out through the holes into passages between the egg-shaped cups which allow
the water to flow along the waterproofed screed to the full bores. A double layer of
agricultural Derbigum was laid to ensure a water-tight environment. The ‘egg
cups’ in the MS 20 are 20mm in height, meaning that the soil medium layer is raised
20mm above the screed. Around the perimeter of the courtyard is a 700mm corridor of
gravel, completely free of fines, and an edging of natural sandstone forming a bund wall,
built on top of the Dorken. This allows a completely free flow of water into the full
bores, particularly in the case of a rainstorm to stop excess water from pooling in front
of the glass doors to the courtyard and possibly flooding the building.
Drip irrigation
The landscape designers wanted to create a model water-wise garden and drip
irrigation was chosen because it is water efficient and operates under low pressure,
meaning no water loss in the windy courtyard conditions. Drip utilises 50-70% less water
than sprinkler irrigation – it allows the application of the least possible amount of
water to meet the plant’s requirements. Drip is also less prone to vandalism and more
aesthetically pleasing.
According to
Marijke Honig, the ideal would have been to have each courtyard on a separate station but
there was not enough water being used in each individual courtyard to create sufficient
pressure for the system to operate. On the advice of drip irrigation specialist, Phillip
Botha, the system was designed with two stations served by two ring mains which were
installed in the ceiling space. Water is fed
down into each courtyard from the ring mains. One station and ring main serves three
courtyards and the other, four courtyards. The control box for the drip irrigation is
located in the air-conditioning control room and it includes a pressure regulator and a
filter. Drip lines with 400mm spacing were installed in a grid in the planted areas, with
two flush valves per courtyard.
The drip
system cycle is adjusted seasonally because there are big climatic extremes in the
courtyards. In winter with its very short days and little direct sunlight, the system is
set on the minimum two cycles a week, whereas in summer when it is windy and there is a
lot of sun, the system operates every second day on a 25 minute cycle. In the heat of the
summer, the watering is done in the early morning. The
succulent courtyard needs infrequent watering and this is done manually.
Honig
comments that there were originally problems with water pressure but these were not
related to the drip system and once the fault in the mains was corrected, the drip system
functioned well. In one of the fynbos courtyards there was insufficient main line
pressure, so the drip system works off a standpipe and battery run timer. She makes the
comment that, after the initial irrigation failure, the fynbos plants showed signs of
severe stress but most survived, with the notable exception of the restios.
Maintenance
For the first 18 months after completion, Think Ecologic was responsible for
the maintenance of the Unicity courtyards and care was taken to ensure the correct working
of the drip irrigation system through checking for wet spots indicative of leaks and flush
valves which did not close off properly; and adjusting the controller programme to suit
plant requirements and weather patterns.
Weeds were
removed manually, taking care to remove the roots to prevent regrowth, and care was taken
to remove weeds in the fynbos courtyards at an early stage of growth (<60mm height), as
removal of large weeds disturbs sensitive roots, resulting in the mortality of fynbos
plants. Self-seeded plants, such as those of Geranium incanum, were allowed to grow where
appropriate.
Regular
feeding is a critical component of plant care in the courtyards because of the shallow
soil and large volume of plants. When feeding was delayed in winter, plants showed signs
of mineral deficiencies and became susceptible to disease. Trees were fertilised with slow
release tablets in September and December and were shaped as required. All plant material was kept free of dead wood,
broken branches and dead flower heads; groundcovers and herbaceous filler plants were
trimmed as required; small succulent plants, Haworthia and Gasteria, were kept clear of
gravel; caudiciform creepers, Dioscorea and Kedostris, were trained to grow up the cone
shaped tree guards and wires; shrubs were pruned after flowering; and the yellow leaves
were removed from the deciduous bulbs, Chasmanthe, Watsonia and Haemanthus, once they had
died back.
From
December to April, a liquid seaweed based feed was applied to the plants on a monthly
basis. At the start of winter, a granular fertiliser was applied – 3:1:5 SR for the
fynbos courtyards and 2:3:2 for the others. Plant material was inspected on a weekly basis
for disease or insect pest infestations. The nature of the infestation was identified and
treated accordingly. Rust was found to be a problem on the aloes, especially in winter.
Scabiosa and Pelargonium peltatum were prone to aphid infestation and had to be controlled
with a pesticide. |
